While the U.S. Air Force pursues development of the Long-Range Strike Bomber project, striving to launch full-scale development next year, both Russia and China are also proceeding with bomber plans. In the case of Russia, the PAK-DA (perspektivnyi aviatsionnyi kompleks dal’ney aviatsii, or future long-range air system) is the first all-new bomber to start development since the Tupolev Tu-160, in 1977, while China’s prospective new system would be the nation’s first indigenous bomber.
Nanodiamond-Rich Layer across Three Continents Consistent with Major Cosmic Impact at 12,800 Cal BP
Authors:
Kinzie et al
Abstract:
A major cosmic-impact event has been proposed at the onset of the Younger Dryas (YD) cooling episode at ≈12,800 ± 150 years before present, forming the YD Boundary (YDB) layer, distributed over greater than 50 million km2 on four continents. In 24 dated stratigraphic sections in 10 countries of the Northern Hemisphere, the YDB layer contains a clearly defined abundance peak in nanodiamonds (NDs), a major cosmic-impact proxy. Observed ND polytypes include cubic diamonds, lonsdaleite-like crystals, and diamond-like carbon nanoparticles, called n-diamond and i-carbon. The ND abundances in bulk YDB sediments ranged up to ≈500 ppb (mean: 200 ppb) and that in carbon spherules up to ≈3700 ppb (mean: ≈750 ppb); 138 of 205 sediment samples (67%) contained no detectable NDs. Isotopic evidence indicates that YDB NDs were produced from terrestrial carbon, as with other impact diamonds, and were not derived from the impactor itself. The YDB layer is also marked by abundance peaks in other impact-related proxies, including cosmic-impact spherules, carbon spherules (some containing NDs), iridium, osmium, platinum, charcoal, aciniform carbon (soot), and high-temperature melt-glass. This contribution reviews the debate about the presence, abundance, and origin of the concentration peak in YDB NDs. We describe an updated protocol for the extraction and concentration of NDs from sediment, carbon spherules, and ice, and we describe the basis for identification and classification of YDB ND polytypes, using nine analytical approaches. The large body of evidence now obtained about YDB NDs is strongly consistent with an origin by cosmic impact at ≈12,800 cal BP and is inconsistent with formation of YDB NDs by natural terrestrial processes, including wildfires, anthropogenesis, and/or influx of cosmic dust.
The following story happened in 1985 but subsequently vanished into obscurity. Over the years, many details have been twisted, others created. Even the original storytellers got some things just plain wrong. After extensive research, writer Nickolai Belakovski is able to present, for the first time to an English-speaking audience, the complete story of Soyuz T-13’s mission to save Salyut 7, a fascinating piece of in-space repair history.
Genetic variation reveals large-scale population expansion and migration during the expansion of Bantu-speaking peoples
Authors:
Li et al
Abstract:
The majority of sub-Saharan Africans today speak a number of closely related languages collectively referred to as ‘Bantu’ languages. The current distribution of Bantu-speaking populations has been found to largely be a consequence of the movement of people rather than a diffusion of language alone. Linguistic and single marker genetic studies have generated various hypotheses regarding the timing and the routes of the Bantu expansion, but these hypotheses have not been thoroughly investigated. In this study, we re-analysed microsatellite markers typed for large number of African populations that—owing to their fast mutation rates—capture signatures of recent population history. We confirm the spread of west African people across most of sub-Saharan Africa and estimated the expansion of Bantu-speaking groups, using a Bayesian approach, to around 5600 years ago. We tested four different divergence models for Bantu-speaking populations with a distribution comprising three geographical regions in Africa. We found that the most likely model for the movement of the eastern branch of Bantu-speakers involves migration of Bantu-speaking groups to the east followed by migration to the south. This model, however, is only marginally more likely than other models, which might indicate direct movement from the west and/or significant gene flow with the western Branch of Bantu-speakers. Our study use multi-loci genetic data to explicitly investigate the timing and mode of the Bantu expansion and it demonstrates that west African groups rapidly expanded both in numbers and over a large geographical area, affirming the fact that the Bantu expansion was one of the most dramatic demographic events in human history.
Short note on an anurognathid pterosaur with a long tail from the Upper Jurassic of China
Authors:
Jiang et al
Abstract:
Pterosaurs consist of an extinct group of flying reptiles that show short- and long-tailed species. Among those are the anurognathids whose phylogenetic position has been considered quite controversial. So far, there are about 10 described specimens from the Anurognathidae, from which only a few show the preservation of caudal elements. Here, we report a new anurognathid specimen (IVPP V16728) from Mutoudeng, Qinglong, Hebei, China that shows the most complete tail of this non-pterodactyloid clade. The preserved part of the tail has at least 20 caudal vertebrae, some showing extended chevrons and zygapophyses, which is a very primitive character within pterosaurs.
Direct evidence of trophic interactions among apex predators in the Late Triassic of western North America
Authors:
Drumheller et al
Abstract:
Hypotheses of feeding behaviors and community structure are testable with rare direct evidence of trophic interactions in the fossil record (e.g., bite marks). We present evidence of four predation, scavenging, and/or interspecific fighting events involving two large paracrocodylomorphs (=‘rauisuchians’) from the Upper Triassic Chinle Formation (∼220–210 Ma). The larger femur preserves a rare history of interactions with multiple actors prior to and after death of this ∼8–9-m individual. A large embedded tooth crown and punctures, all of which display reaction tissue formed through healing, record evidence of a failed attack on this individual. The second paracrocodylomorph femur exhibits four unhealed bite marks, indicating the animal either did not survive the attack or was scavenged soon after death. The combination of character states observed (e.g., morphology of the embedded tooth, ‘D’-shaped punctures, evidence of bicarination of the marking teeth, spacing of potentially serial marks) indicates that large phytosaurs were actors in both cases. Our analysis of these specimens demonstrates phytosaurs targeted large paracrocodylomorphs in these Late Triassic ecosystems. Previous distinctions between ‘aquatic’ and ‘terrestrial’ Late Triassic trophic structures were overly simplistic and built upon mistaken paleoecological assumptions; we show they were intimately connected at the highest trophic levels. Our data also support that size cannot be the sole factor in determining trophic status. Furthermore, these marks provide an opportunity to start exploring the seemingly unbalanced terrestrial ecosystems from the Late Triassic of North America, in which large carnivores far outnumber herbivores in terms of both abundance and diversity.
Potential Ediacaran Sponge Gemmules from the Yangtze Gorges area in South China
Authors:
Du et al
Abstract:
Sponges are widely viewed as the most primitive metazoans. Sponge gemmule-like structures have been recovered from the lower part of the Doushantuo Formation in the Yangtze Gorges area (South China), that was deposited between 635 to 580 Ma. Gemmoscleres-like structures are embedded in the outer coat of the sponge structures. Electron probe microanalyses EPMA) of the gemmoscleres-indicate that they have siliceous composition. The naked subspheroidal sponge structures are composed of three layers, consistent with the preservation of a tri-layered theca embedded with the gemmosclere-like structures. The potential fossils of the Ediacaran sponge gemmules in the Doushantuo Formation may provide one of the earliest records of sponges.
Patriarch Kirill, the head of the Russian Orthodox Church, was presented with an unlikely gift for a religious leader this week as he toured a factory in Russia's far-east - a single-seater fighter jet SU-35.
Kirill was presented with the jet after giving workers at the civilian and military aircraft plant icons blessed by himself, the church said in a statement on its official website on Tuesday.
The patriarch, with whom President Vladimir Putin has fostered increasingly close ties in recent years, addressed the workers on the importance of protecting Russia.
"Russia cannot be a vassal. Because Russia is not only a country, it is a whole civilization, it is a thousand-year story, a cultural melting-pot, of enormous power," RIA news agency quoted him as saying.
"In order for us to be able to live a sovereign life, we must, if necessary, be able to defend our homeland."
IT IS crisis mode in the Kantei, the office of Shinzo Abe, Japan’s prime minister. A succession of awful data has pummelled his economic programme, which consists of three “arrows”: a radical monetary easing, a big fiscal stimulus and a series of structural reforms. On September 8th revised figures showed that GDP shrank by 1.8% in the second quarter, or by 7.1% on an annualised basis, even worse than the initial estimate of 1.7%.
Evaluating an icon of population persistence: the Devil's Hole pupfish
Authors:
Reed et al
Abstract:
The Devil's Hole pupfish Cyprinodon diabolis has iconic status among conservation biologists because it is one of the World's most vulnerable species. Furthermore, C. diabolis is the most widely cited example of a persistent, small, isolated vertebrate population; a chronic exception to the rule that small populations do not persist long in isolation. It is widely asserted that this species has persisted in small numbers (less than 400 adults) for 10 000–20 000 years, but this assertion has never been evaluated. Here, we analyse the time series of count data for this species, and we estimate time to coalescence from microsatellite data to evaluate this hypothesis. We conclude that mean time to extinction is approximately 360–2900 years (median 410–1800), with less than a 2.1% probability of persisting 10 000 years. Median times to coalescence varied from 217 to 2530 years, but all five approximations had wide credible intervals. Our analyses suggest that Devil's Hole pupfish colonized this pool well after the Pleistocene Lakes receded, probably within the last few hundred to few thousand years; this could have occurred through human intervention.
In a report released earlier this month but which only caught the bitcoin community’s eyes these past two days, the Boston Fed concludes that “the lasting legacy of Bitcoin most likely lies in the technological advances made possible by its protocol for computation and communication.”
Authors J. Christina Wang, a senior economist in the Boston Fed’s research department, and Harvard University economist Stephanie Lo note that this decentralized technology could disrupt a current bank-centric payment system that’s “fragmented” and “inefficient.”
They join St. Louis Fed Chief Economist David Andalfatto, who put out a report on cryptocurrency earlier this year, in specifically acknowledging bitcoin competitor Ripple as a contender for this role. Describing that startup’s network as “essentially a protocol that allows disparate systems to communicate in order to transfer funds and make payments,” the report says Ripple shows that “the development of new technologies for making payments does not need to be accompanied by a new financial claim” – in other words, a new digital currency to compete with traditional currencies. (Ripple has its own native currency, called XRP, but not every transaction requires it and end users typically don’t trade in it, with most transfers passing only momentarily through XRP. The financial service providers that serve as Ripple gateways can distribute and receive payments in sovereign fiat currencies.)
Bitcoin did not miss out on praise. The authors say “it’s conceivable for bitcoin to capture a nonnegligible market share” of e-commerce, noting that despite extreme volatility in its exchange rate, data show that people engaging in bitcoin transactions on average save money over traditional payment methods by avoiding the bigger transaction fees imposed by banks. They especially highlighted bitcoin’s promise in cross-border remittances and while they pointed out thatthis could be held back by underdeveloped personal computing technology and knowledge in developing countries, cellphone technology offers an attractive way around these limitations.
Notably, the report takes a critical look at the mining network, a vital component of the bitcoin infrastructure through which its coins are issued and its transaction ledger is updated. The report describes the competition mechanism that has produced a concentration of mining power as one of bitcoin’s “serious design flaws,” raising concern that reduced profitability for small miners will further concentrate power and could undermine the integrity of the system. The authors even raise the prospect of regulation to manage the mining network – “it suggests the need for enhanced oversight, either by the players themselves or by an independent third party, to guard against the likelihood of collusion or other noncompetitive behavior,” they wrote.
Ms. Wang and Ms. Lo also highlight the fact that more high-powered, independent computers could soon be needed to store the large amounts of data that bitcoin’s blockchain ledger of transactions will contain.
Based on these concerns, they contend that the bitcoin network, “as originally designed, and especially its associated digital currency, will probably not survive in the long run.”
We have 3-D printed keys, guns and shoes—now a research team at the University of Virginia has created a 3D printed UAV drone for the Department of Defense.
In the works for three years, the aircraft, no bigger than a remote-controlled plane, can carry a 1.5-pound payload. If it crashes or needs a design tweak for a new mission, another one can be printed out in a little more than a day, for just $2,500. It’s made with off-the-shelf parts and has an Android phone for a brain.
“We weren’t sure you could make anything lightweight and strong enough to fly,” says David Sheffler, who led the project. Sheffler is a former engineer for Pratt & Whitney and Rolls-Royce who now teaches at the university. After he created a 3-D printed jet engine in one of his classes, the MITRE Corporation, a DoD contractor, asked him to create a 3-D printed UAV that could be easily modified and built with readily available parts.
The first prototype, the orange and blue model seen in the video above, was based on a conventional radio-controlled (RC) aircraft made of balsa wood, which is much lighter and stronger than the ABS plastic used in the university’s 3-D printers. The same plane made of plastic would have weighed five times as much as the wood version. “You’re printing out of a material that’s really not well-suited to making an airplane,” Sheffler explains. On top of that, the way 3-D printing works—building things in layers—led to structural weaknesses in the aircraft.
To account for those downsides, Sheffler’s team reworked the design. They settled on a “flying wing” design, in which the whole aircraft is basically one big wing, and called it the Razor. The latest (third) prototype is made of nine printed parts that click together like LEGO. The center of the plane is all one piece, with a removable hatch that offers access the inner cargo bay. All of the electronics live in there, including a Google Nexus 5 smartphone running a custom-designed avionics app that controls the plane, and an RC-plane autopilot that manages the control surfaces with input from the phone. The Razor’s wing structure is one piece, with an aileron, winglets, and mount for the small jet engine that clip on
Defense giant Lockheed Martin, Notre Dame University, DARPA and the Air Force Research Lab have begun flight testing a streamlined and greatly miniaturized airborne laser turret that has the potential to totally transform air combat as we understand it today.
This new state-of-the-art beam control turret allows for 360 degree aiming coverage for directed energy weapons that will be flying on military aircraft in the not so distant future. In other words, this turret is able to rapidly aim at targets and focus a directed energy burst through the atmosphere at those targets to disable or destroy them, all while flying on a aircraft barreling through the sky at high-speed.
The head of the Air Force Research Laboratory on Sept. 16 said the first test of a hypersonic aircraft could come within five years, and the technology could be applied to cruise missiles by the 2020s.
Maj. Gen. Tom Masiello, commander of the Air Force Research Laboratory, said hypersonics is one of the most promising technologies the lab is working on. It is currently testing the Boeing X-51 WaveRider unmanned hypersonic vehicle.
Hypersonic planes, lasers and unmanned aircraft are all considered major aviation game changers, he said.
“Hypersonic is the technology of the future,” Masiello said during the Air Force Association’s Air and Space Conference at National Harbor, Maryland. “I can’t overemphasize the significance of the X-51.”
Following a successful and historic test of the X-51 last year, momentum has been growing, Masiello said. During the test, the vehicle reached speeds of Mach 5.1 and traveled 230 nautical miles in about six minutes.
When operational, a hypersonic aircraft will give the military the ability to strike time-sensitive targets and could be used in an anti-access/area-denial environment, Masiello said. Survivability in A2/AD situations is critical as the nation focuses on the Asia-Pacific region, which has a higher threat of such attacks, he said.
“[From] a survivability stand point, it’s about altitude, it’s about speed. It’s just plain physics in terms of a missile being able to intercept a cruise missile going at Mach 5 plus, up at 50,000 [or] 60,000 feet,” Masiello said. “In any A2/AD environment, regardless of the Asia Pacific or anywhere else … that ability to survive in a highly contested environment is a huge attribute.”
The test was the fourth of its kind, and followed two previous failures. Previously, the aircraft’s supersonic combustion ramjet engine — also known as a scramjet — failed to light during the second test. A fin fell off of the aircraft during the third test.
Masiello said past failures were opportunities to better understand the technology, and a necessary part of the test-and-evaluation process.
“Within an S&T environment, we have to protect the opportunity to fail or else you’re not going to make any real progress,” Masiello said. “In early R&D and S&T, there are going to be failures.”
The success of the fourth test proved that this type of futuristic technology is real, Masiello said.
Demonstrations of an aircraft should happen within the next five years, he said. The X-51 resembles a missile and is launched from a B-52. By the 2020s, the Air Force wants to weaponize the technology to use it as a cruise missile, he added.
Plant Ecological Strategies Shift Across the Cretaceous–Paleogene Boundary
Authors:
Blonder et al
Abstract:
The Chicxulub bolide impact caused the end-Cretaceous mass extinction of plants, but the associated selectivity and ecological effects are poorly known. Using a unique set of North Dakota leaf fossil assemblages spanning 2.2 Myr across the event, we show among angiosperms a reduction of ecological strategies and selection for fast-growth strategies consistent with a hypothesized recovery from an impact winter. Leaf mass per area (carbon investment) decreased in both mean and variance, while vein density (carbon assimilation rate) increased in mean, consistent with a shift towards “fast” growth strategies. Plant extinction from the bolide impact resulted in a shift in functional trait space that likely had broad consequences for ecosystem functioning.
Jeff Bezos, founder of the online retailing giant Amazon.com, has unveiled a new commercial engine design for legacy military rockets.
Bezos, who also heads up the private spaceflight company Blue Origin LLC, was on hand with Tony Bruno, the new chief executive officer of the Lockheed Martin Corp.-Boeing Co. joint venture, United Launch Alliance LLC, on Wednesday at the National Press Club to announce an agreement to jointly fund development of the BE-4 engine.
A single engine is designed to provide 550,000 pounds of thrust and replace the Russian-made RD-180 propulsion system currently on the Atlas V rocket, one of two boosters used by the Air Force’s Evolved Expendable Launch Vehicle program to lift military and spy satellites into space.
“This business is too hard if you’re not passionate about it,” Bezos said, referring to space launch. “Cost and reliability are the two driving factors.”
In a statement released after the event, he said, “The team at Blue Origin is methodically developing technologies to enable human access to space at dramatically lower cost and increased reliability, and the BE-4 is a big step forward. With the new ULA partnership, we’re accelerating commercial development of the next great US-made rocket engine.”
Bruno, who last month replaced Michael Gass in a sudden change in leadership at ULA, said the partnership between the defense contracting giant and the space tourism start-up represented “the best of both worlds.”
In the statement, he said, “Blue Origin has demonstrated its ability to develop high-performance rocket engines and we are excited to bring together the best minds in engineering, supply chain management and commercial business practices to create an all-new affordable, reliable, American rocket engine that will create endless possibilities for the future of space launch.”
The pact calls for developing the engine over four years, with full-scale testing in 2016 and first flight in 2019. The system will be available for use on either ULA or Blue Origin rockets.
New studies of ancient DNA are shifting scientists' ideas of how groups of people migrated across the globe and interacted with one another thousands of years ago. By comparing nine ancient genomes to those of modern humans, Howard Hughes Medical Institute (HHMI) scientists have shown that previously unrecognized groups contributed to the genetic mix now present in most modern-day Europeans.
"There are at least three major, highly differentiated populations that have contributed substantial amounts of ancestry to almost everybody that has European ancestry today," says David Reich, an HHMI investigator at Harvard Medical School. Those include hunter-gatherers from western Europe, the early farmers who brought agriculture to Europe from the Near East, and a newly identified group of ancient north Eurasians who arrived in Europe sometime after the introduction of agriculture. That means there were major movements of people into Europe later than previously thought. The team, led by Reich and Johannes Krause at the University of Tübingen in Germany, reported their findings in the September 18, 2014, issue of the journal Nature.
In the last five years, genetic evidence has demonstrated that migrants from the Near East brought agriculture with them to Europe when they arrived about 8,500 years ago. But the genomes of present-day Europeans show signs that they come from more than just the indigenous hunter-gatherers and these early farmers.
Two years ago, Reich's group uncovered genetic evidence that most present-day Europeans are a mixture of groups related to southern Europeans, Near Easterners, and a third group most closely related to Native Americans. "That was a crazy observation, but it's very strong statistically," Reich says. "We argued that this is because of the contribution of an ancient north Eurasian population some of whose members contributed to the peopling of the Americas more than 15,000 years ago, and others of which later migrated to Europe."
To clarify that early history, Reich's team, including more than 100 collaborators worldwide, collected genetic data from nine ancient skeletons and 203 present-day populations living all over the world. Collaborators isolated human DNA and sequenced the complete genomes from the bones of a 7,000-year old skeleton found in Germany and eight skeletons of hunter-gatherers who lived in Luxembourg and Sweden about 8,000 years ago. They compared those genomes to those of the 2,345 people in their contemporary populations.
That required developing new computational methods for genetic analysis. "Figuring out how these populations are related is extremely hard," Reich says. "There's a lot that happened in Europe in the last 8,000 years, and this history acts like a veil, making it difficult to discern what happened at the beginning of this period. We had to find statistics that were able to tell us what happened deep in the past without getting confused by 8,000 years of intervening history, when massive and important events occurred."
"What we find is unambiguous evidence that people in Europe today have all three of these ancestries: early European farmers who brought agriculture to Europe, the indigenous hunter-gatherers who were in Europe prior to 8,000 years ago, and these ancient north Eurasians," Reich says. Further analyses showed that describing present-day Europeans as a mixture of the three populations is a good fit for most, although not all, populations.
When the study began, the ancient north Eurasian population was a "ghost population" – identified based on genetic patterns without any ancient DNA. But in 2013, another group analyzed DNA from two skeletons found in Siberia, one from 24,000 years ago and one from 17,000 years ago, and found that it shared genetic similarities with Europeans and North Americans. The ghost, Reich says, had been found.
Although DNA from ancient north Eurasians is present in nearly all modern Europeans, Reich's team did not find it in their ancient hunter-gatherers or the ancient farmers. That means the north Eurasian line of ancestry was introduced into Europe after agriculture had been established, a scenario most archaeologists had thought unlikely.
"We have this amazing observation that only two ancestries are represented among the first farmers, from about 7,000 to 5,000 years ago. And then suddenly everybody today has ancient north Eurasian ancestry," Reich says. "So there must have been a later movement of this ancestry into Europe."
Anthropologists have long thought that densely settled populations would be resistant to the arrival of new groups. "But this is hard evidence that exactly such a major migration occurred," Reich says. "It's very important because it's a major contributor to Europeans today." The time of the ancient north Eurasians' arrival remains to be determined, but Reich says their later-than-expected movement into Europe might help explain the complex mix of languages that exists there today.
The team's data also reveals that the first farmers to reach Europe from the Near East had ancestors from a previously unidentified lineage, which Reich's group named the Basal Eurasians. Basal Eurasians were the first people to separate from the larger group of non-Africans, before other non-African groups diversified. Reich says that attempts to identify the first group to split from the non-Africans had always been puzzling: genetic evidence indicates that this is likely to be Europeans or Near Easterners, even though some archaeological evidence has indicated that people were in New Guinea and Australia before they were Europe.
The new analysis shows that the Near Easterners who came into Europe 8,000 years ago brought with them a strand of ancestry that had separated before the ancestors of Australian aborigines separated from the indigenous people of Europe. "That population must have been hanging out somewhere in the Near East for a very long time," Reich says. Now he would like to know how that population fits into the archaeological history of the region. Ancient DNA from Basal Europeans, if found, might lead to new revelations about early human history.
Medullary bone-like tissue in the mandibular symphyses of a pterosaur suggests non-reproductive significance
Authors:
Prondvai et al
Abstract:
Medullary bone is a special bone tissue forming on the endosteal surface of the medullary cavity in the bones of female birds prior to and during egg-laying to serve as a calcium reservoir for building the hard eggshell. It has also been identified in non-avian dinosaurs, where its presence is considered as a reliable indicator of a sexually mature female. Here, we reveal that multiple mandibular symphyses of the azhdarchid pterosaur Bakonydraco galaczi possess a special bone tissue that shows all microanatomical, histological, and developmental characteristics of medullary bone, despite its unusual location. Its frequent occurrence in the sample renders a pathologic origin unlikely. Our findings as well as the extremely thin-shelled eggs of pterosaurs suggest that this medullary bone-like tissue probably had a non-reproductive role in these animals. Although the non-reproductive significance and the anatomical location of this medullary bone-like tissue in Bakonydraco suggest independent evolutionary appearance from dinosaurian medullary bone, a common origin and later diverging function and physiological regulation is an equally viable phylogenetic hypothesis.
On a new stereospondylomorph temnospondyl from the Middle/Late Permian of Southern Brazil
Authors:
Strapasson et al
Abstract:
A new temnospondyl is described from the Middle/Upper Permian sequence of the Paraná Basin (Rio do Rasto Formation) in southern Brazil. The material consists of disarticulated cranial and postcranial elements, preserved in association. The cranial elements include part of the orbital region of the skull roof, the basicranium, a number of endocranial elements, stapes and a right hemimandible. The postcranial elements include vertebrae, ribs, pectoral girdle elements, a right femur and a cluster of scales. The new species displays a rhinesuchid pattern, which is similar to the South African rhinesuchids from the Upper Permian Beaufort Group of the Karoo Basin, but differs from them by the presence of a robust and elongated epipterygoid with a blade-like anterior process in addition to elongated and deeper muscular pockets on the parasphenoid, which allow the assignment of this specimen to a new species. However, the phylogenetic analysis grouped the material described herein and Australerpeton cosgriffi (Barberena, 1998) inside Stereospondylomorpha, in a transitional position between the Laurasian assemblages and South African temnospondyls. This result supports a connection between the Brazilian and Eastern European Permian fauna and provides important data for future biostratigraphic studies.
Detrital zircon U–Pb ages and Hf isotopes of Neoproterozoic strata in the Aksu area, northwestern Tarim Craton: Implications for supercontinent reconstruction and crustal evolution
Authors:
He et al
Abstract:
The northern margin of the Tarim Craton plays a pivotal role in understanding the crustal evolution and supercontinent reconstruction of the Tarim Craton. Here we integrate LA-ICP-MS U–Pb ages and Hf isotopic data for detrital zircons from Neoproterozoic successions in the Aksu area, NW Tarim. A total of 679 concordant U–Pb ages define four age populations of 2600–2200 Ma, 2050–1800 Ma, 950–700 Ma and 680–600 Ma, which are consistent with the episodes of magmatism and metamorphism documented in the northern Tarim Craton, suggesting that the detritus were likely sourced from the northern Tarim Craton itself. The oldest age population corresponds to the Neoarchean to early Paleoproterozoic magmatic event related to an important stage in the development of the proto continental crust in the Tarim Craton. The 2050–1800 Ma age population represents a magmatic–metamorphic event during a middle Paleoproterozoic orogeny, possibly related to the assembly of Tarim to the Columbia supercontinent. The dominant Neoproterozoic detrital zircons display a major cluster between 950 Ma and 700 Ma (peak at ca. 850 Ma), much younger than the typical Grenvillian ages. This is similar to detrital zircon data sets from Yangzte and northern India, implying that these blocks shared a similar evolution pattern in the Rodinia supercontinent. The early Pan-African (680–600 Ma) ages are comparable with those reported from the Arabian-Nubian Shield, but quite different from those from other Gondwana blocks, implying a possible correlation of Tarim with the Eastern Africa Orogen. Abundant zircons yield Archean (3.9–2.5 Ga) Hf model ages (TDMC), suggesting the presence of extensive Archean basement as old as Paleoarchean in the Tarim Craton. Some Neoarchean and Neoproterozoic zircons have high positive É›Hf(t) values, indicating significant juvenile addition from the depleted mantle at those periods. However, most detrital zircons show negative É›Hf(t) values, suggesting that crustal reworking was the dominant process in the generation of the episodes of magmatism in the Tarim Craton. At last, based on the stratigraphic settings and the comparison of detrital zircon data, the Aksu Group and the Qiaoenbrak Formation are most likely units with equivalent depositional age.
Despite political opposition and apparently contradictory ministerial statements, it appears increasingly likely that Australia will replace its Collins-class submarines with 4,200-tonne Soryu-class submarines built in Japan.
Amid intense media speculation about such an agreement, Prime Minister Tony Abbott said on 8 September that a decision on replacing the six Australian-built, 3,400-tonne Collins-class submarines under Project Sea 1000 would be based on capability, value for money, and regional rather than industrial policy.
"The most important thing is to get the best and most capable submarines at a reasonable price for the Australian taxpayer," he said.
The current life-of-type of the Collins fleet runs from 2024 to 2031, although there are no apparent issues to prevent some or all of the class having service life extended by up to 10 years.
Several sources have put the cost of 10 Japanese-constructed submarines at about AUD20 billion (USD18.3 billion), compared with an estimated AUD36 billion for an Australian-designed and built replacement.
On 9 September Defence Minister David Johnston said the bulk of what he described as "the Australian work" on future submarines would be carried out in South Australia - a remark which an authoritative source subsequently clarified as referring to maintenance, not construction.
Federal Opposition Leader Bill Shorten meanwhile accused Abbott of putting Australia's national security at risk by considering the acquisition of completed submarines from Japan, and pledged to cancel any such agreement should the Labor Party win the next election - due in August 2016.
Although a decision on Sea 1000 had been anticipated as part of a Defence White Paper due to be published in mid-2015, there is now speculation that selection of the Japanese option could be announced as early as the Group of 20 leaders' meeting in Brisbane in November.
In April Johnston described the Soryu class as the platform closest to Australia's requirements and repeated earlier remarks about Australia's interest in the type's drive train.
Alex Salmond has said the independence vote is a "once in a generation" opportunity as he pledged not to quickly bring back another referendum if Scots choose to remain in the UK.
Commentators have been predicting a "neverendum" if the No campaign wins on Thursday by a narrow margin, with nationalists calling for a new independence poll within a few years.
As a series of polls indicate the vote remains too close to call, Mr Salmond was asked if he could pledge not to bring back another referendum if the Yes campaign does not win on Thursday, he said: "That's my view. My view is this is a once in a generation, perhaps even a once in a lifetime, opportunity for Scotland."
Russia is set to become the latest country to restrict virtual currencies such as Bitcoin, after a top official announced that a law will be passed banning their exchange into real money by next spring due to their use by criminals and terrorists.
Deputy Finance Minister Aleksey Moiseev said: “People can play with their chips, and they can call them money, but they can’t use these surrogate currencies as tender.
“We will discuss this law in the current session of parliament, and possibly even pass it then, or at the very latest by spring next year.
"We are currently dealing with comments from the law enforcement agencies, about the specifics of legal measures, and we will take their remarks into account. But the overall concept of the law is set in stone.”
Although the draft of the proposed legislation has not been published, officials say they will open criminal proceedings against both those who mint digital currency, usually with the help of powerful computers, and those who use them for transactions. The finance ministry has also asked regulators to ban access to exchanges and online stores that accept bitcoin.
A biologically inspired smart suit that fits under clothing and could help soldiers walk farther, tire less easily, and carry heavy loads more safely has been given a boost that could be as much as $2.9 million.The Wyss Institute for Biologically Inspired Engineering at Harvard University announced today that it has been awarded a first-phase, follow-on contract from the Defense Advanced Research Projects Agency (DARPA) to further develop its Soft Exosuit — a wearable robot — alternative versions of which could eventually help those with limited mobility as well.Technologies developed by DARPA’s Warrior Web program aim to prevent and reduce musculoskeletal injuries for military personnel, but can have civilian applications, too. The suit could reduce long-term health care costs and enhance the quality of life for people on and off the battlefield.The award is the first of what could be a two-phase contract, and it enables Wyss Institute core faculty member Conor Walsh and his team to build upon their earlier work (also funded by DARPA) demonstrating the proof-of-concept of this radically new approach to wearable robot design and fabrication. Inspired by a deep understanding of the biomechanics of human walking, Soft Exosuit technology is spawning development of entirely new forms of functional textiles, flexible power systems, soft sensors, and control strategies that enable intuitive and seamless human-machine interaction.“While the idea of a wearable robot is not new, our design approach certainly is,” said Walsh, an assistant professor of mechanical and biomedical engineering at Harvard’s School of Engineering and Applied Sciences (SEAS) and founder of the Harvard Biodesign Lab.The lightweight Soft Exosuit overcomes the drawbacks of traditional, heavier exoskeleton systems, such as power-hungry battery packs and rigid components that can interfere with natural joint movement. It is made of soft, functional textiles woven into a piece of smart clothing that is pulled on like a pair of pants, and is intended to be worn under a soldier’s regular gear. The suit mimics the action of leg muscles and tendons when a person walks, and provides small but carefully timed assistance at the leg joints without restricting the wearer’s movement.In a current prototype, a series of webbing straps around the lower half of the body contain a low-power microprocessor and a network of supple strain sensors. These act as the “brain” and “nervous system” of the Soft Exosuit, respectively, continuously monitoring various data signals, including suit tension, wearer position (walking, running, crouched), and more.
Lockheed Martin in partnership with the Air Force Research Laboratory (AFRL) and the University of Notre Dame, has demonstrated the airworthiness of a new beam control turret being developed for the Defense Advanced Research Projects Agency (DARPA) and AFRL to give 360-degree coverage for high-energy laser weapons operating on military aircraft. A research aircraft equipped with the Aero-adaptive Aero-optic Beam Control (ABC) turret conducted eight flights in Michigan.link.
"These initial flight tests validate the performance of our ABC turret design, which is an enabler for integrating high energy lasers on military aircraft," said Doug Graham, vice president of advanced programs, Strategic and Missile Defense Systems, Lockheed Martin Space Systems.
The ABC turret system is designed to allow high-energy lasers to engage enemy aircraft and missiles above, below and behind the aircraft. Lockheed Martin's flow control and optical compensation technologies counteract the effects of turbulence caused by the protrusion of a turret from an aircraft's fuselage.
All turret components met U.S. Air Force and Federal Aviation Administration airworthiness requirements.
Subsequent flight tests over the next year will demonstrate the turret in increasingly complex operations.
Interpreting carbonate and organic carbon isotope covariance in the sedimentary record
Authors:
Oehlert et al
Abstract:
Many negative δ13C excursions in marine carbonates from the geological record are interpreted to record significant biogeochemical events in early Earth history. The assumption that no post-depositional processes can simultaneously alter carbonate and organic δ13C values towards more negative values is the cornerstone of this approach. However, the effects of post-depositional alteration on the relationship between carbonate and organic δ13C values have not been directly evaluated. Here we present paired carbonate and organic δ13C records that exhibit a coupled negative excursion resulting from multiple periods of meteoric alteration of the carbonate δ13C record, and consequent contributions of isotopically negative terrestrial organic matter to the sedimentary record. The possibility that carbonate and organic δ13C records can be simultaneously shifted towards lower δ13C values during periods of subaerial exposure may necessitate the reappraisal of some of the δ13C anomalies associated with noteworthy biogeochemical events throughout Earth history.
With the completion of the sequencing and analysis of the gibbon genome, scientists now know more about why this small ape has a rapid rate of chromosomal rearrangements, providing information that broadens understanding of chromosomal biology.
Chromosomes, essentially the packaging that encases the genetic information stored in the DNA sequence, are fundamental to cellular function and the transmission of genetic information from one generation to the next. Chromosome structure and function is also intimately related to human genetic diseases, especially cancer.
The sequence and analysis of the gibbon genome (all the chromosomes) was published today in the journal Nature and led by scientists at Oregon Health & Science University, the Baylor College of Medicine Human Genome Sequencing Center and the Washington University School of Medicine's Genome Institute.
"Everything we learn about the genome sequence of this particular primate and others analyzed in the recent past helps us to understand human biology in a more detailed and complete way," said Dr. Jeffrey Rogers, associate professor in the Human Genome Sequencing Center at Baylor and a lead author on the report. "The gibbon sequence represents a branch of the primate evolutionary tree that spans the gap between the Old World Monkeys and great apes and has not yet been studied in this way. The new genome sequence provides important insight into their unique and rapid chromosomal rearrangements."
In modern scientific researches of biological direction the geographic information systems (GIS) are increasingly used. For example, GIS technology is successfully applied in the study of patterns of spatial and temporal distribution of biological objects with taking into account the unique features of the environment. Typically, a GIS is used for the analysis of current events and / or the future forecast, but they are also useful for the study of the fossils, living conditions in the distant past, changes in biodiversity and for determining historical patterns of biosphere evolution.
Convenience of GIS for integrated paleontological studies is due to the combination of database management systems functionality, editors of raster and vector graphics and a variety of analytical tools.
Over the last decades of paleontological researches a huge number of fossils belonging to a variety of species of animals, plants and microorganisms has been found. For a comprehensive qualitative analysis of this information it is not enough to draw on the paper map a certain amount of points. Maximum efficiency of the analysis can be achieved by creating a database and its integration with GIS. But if not so long ago each individual researcher or a research institute tried to do their own, as a rule, small databases containing information gathered only by them, but now there is a fundamentally new approach to automate many operations and combine the efforts of many scientists and research teams from all over the world. The projects that implement in practice, such approaches already exist. Paleobiology Database (Paleontological database) can be considered as one of them, 350 specialists from 133 institutions in 24 countries took part in this work. Currently this database contains information on more than a million found fossils, and it is open and available for use under the license of Creative Commons.
Redescription of the Skull of Coloradisaurus brevis (Dinosauria, Sauropodomorpha) from the Late Triassic Los Colorados Formation of the Ischigualasto-Villa Union Basin, northwestern Argentina
Authors:
Apaldetti et al
Abstract:
The cranial anatomy of the basal sauropodomorph Coloradisaurus brevis from the upper levels of the Norian Los Colorados Formation is here redescribed and comparisons made based on the holotype skull and mandible. Coloradisaurus brevis is diagnosed by most of the features proposed in the original description and an additional set of autapomorphies, such as presence of circular upper temporal fenestrae, laminae on the ventrolateral margins of a ventral fossa of the basisphenoid and on the ventral region of the parasphenoid, and tab-like medial process at the posteromedial end of the mandible. Coloradisaurus is placed within Massospondylidae, as in recent analyses. This position is supported primarily by postcranial characters, but some cranial features identified in this study provide additional evidence supporting this position (e.g., jugal contribution to the antorbital fenestra, frontal proportionately longer than nasals). However, the cranial anatomy of Coloradisaurus also bears several characters that are shared with plateosaurids (e.g., low mandibular articulation, broad maxillary wall on the anterior margin of antorbital fossa, broad prefrontals, projection of infratemporal fenestra behind the orbit, stepped braincase, robust septum between basipterygoid processes). Thus, Coloradisaurus is interpreted as a massospondylid that has convergently acquired characters that are otherwise only known in plateosaurids, highlighting the conflicting pattern of character distribution among basal sauropodomorphs.
Iceland is not a magmatic analog for the Hadean: Evidence from the zircon record
Authors:
Carley et al
Abstract:
Tangible evidence of Earth's earliest (Hadean; greater than 4.0 Ga) crust, and the processes and materials that contributed to its formation, exists almost entirely in a record of detrital zircon from Jack Hills, Western Australia, and a few other locations. Iceland, with its thick, juvenile, basaltic crust and relatively abundant silicic rocks, is considered a potential modern analog for the Hadean magmatic environment where greater than 4 Ga zircon formed. We present the first extensive dataset for Icelandic zircon, with trace element and oxygen isotope compositions from samples that span the island's history and full range of tectonic settings. This statistically robust zircon-based comparison between Iceland and the early Earth reveals distinctions in chemistry that suggest fundamental differences in magmatic environments. Whereas the δ 18O signature of Hadean zircons generally exceed that of zircons equilibrated with mantle-derived magma (85%≥5.3‰85%≥5.3‰; median 6‰), almost all Icelandic zircons are characterized by a “light” oxygen signature (98%≤5.3‰98%≤5.3‰; median 3‰). Deviations from “juvenile” oxygen values indicate that many Hadean zircons and almost all Icelandic zircons grew from magmas with substantial contributions from materials that had interacted with surface waters. In the Hadean case, the interaction occurred at low temperatures, while in Iceland, it was a high-temperature interaction. Icelandic and Hadean zircons are also distinct in their Ti concentrations (Icelandic median concentration 12 ppm, Hadean median 5 ppm). Titanium in zircon correlates positively with temperature of crystallization, and this difference in median Ti concentration suggests a temperature difference of at least 50 °C. Other differences in trace elements compositions are consistent with the interpretation that Icelandic and Hadean zircons grew in magmas with very different origins and histories (e.g., the heavy rare earth element Yb is almost an order of magnitude higher in Icelandic zircon). A comparison with elemental data for Phanerozoic zircon from different environments demonstrates that the Hadean population is unusually depleted in Ti, but otherwise similar to zircons from continental arc settings. Zircons from Iceland, and from modern evolving rift environments where oceanic lithosphere and upwelling asthenosphere are replacing continental lithosphere, are compositionally intermediate between mid-ocean ridge and continental arc zircon populations. The elemental distinctions are consistent with fractionation of zircon-bearing magmas under hotter and drier conditions in Icelandic, mid-ocean ridge, and evolving rift environments and cooler and wetter conditions in arc and, especially, Hadean environments.
Early-life exposure to climate change impairs tropical shark survival
Authors:
Rosa et al
Abstract:
Sharks are one of the most threatened groups of marine animals worldwide, mostly owing to overfishing and habitat degradation/loss. Although these cartilaginous fish have evolved to fill many ecological niches across a wide range of habitats, they have limited capability to rapidly adapt to human-induced changes in their environments. Contrary to global warming, ocean acidification was not considered as a direct climate-related threat to sharks. Here we show, for the first time, that an early ontogenetic acclimation process of a tropical shark (Chiloscyllium punctatum) to the projected scenarios of ocean acidification (ΔpH = 0.5) and warming (+4°C; 30°C) for 2100 elicited significant impairments on juvenile shark condition and survival. The mortality of shark embryos at the present-day thermal scenarios was 0% both at normocapnic and hypercapnic conditions. Yet routine metabolic rates (RMRs) were significantly affected by temperature, pH and embryonic stage. Immediately after hatching, the Fulton condition of juvenile bamboo sharks was significantly different in individuals that experienced future warming and hypercapnia; 30 days after hatching, survival rapidly declined in individuals experiencing both ocean warming and acidification (up to 44%). The RMR of juvenile sharks was also significantly affected by temperature and pH. The impact of low pH on ventilation rates was significant only under the higher thermal scenario. This study highlights the need of experimental-based risk assessments of sharks to climate change. In other words, it is critical to directly assess risk and vulnerability of sharks to ocean acidification and warming, and such effort can ultimately help managers and policy-makers to take proactive measures targeting most endangered species.
The May 2014 Moscow Conference on International Security (MCIS), sponsored by the Russian Ministry of Defense, was focused on the role of popular protest, and specifically color revolutions, in international security. The speakers, which included top Russian military and diplomatic officials such as Defense Minister Sergei Shoigu and Foreign Minister Sergei Lavrov, argued that color revolutions are a new form of warfare invented by Western governments seeking to remove independently-minded national governments in favor of ones controlled by the West. They argued that this was part of a global strategy to force foreign values on a range of nations around the world that refuse to accept U.S. hegemony and that Russia was a particular target of this strategy.
While the West considers color revolutions to be peaceful expressions of popular will opposing repressive authoritarian regimes, Russian officials argue that military force is an integral part of all aspects of color revolutions. Western governments start by using non-military tactics to change opposing governments through color revolutions that utilize the protest potential of the population to engineer peaceful regime change. But military force is concealed behind this effort. If the protest potential turns out to be insufficient, military force is then used openly to ensure regime change. This includes the use of external pressure on the regime in question to prevent the use of force to restore order, followed by the provision of military and economic assistance to rebel forces. If these measures are not sufficient, Western states organize a military operation to defeat government forces and allow the rebels to take power. Russian officials at the MCIS conference described color revolutions as a new technique of aggression pioneered by the United States and geared toward destroying a state from within by dividing its population. The advantage of this technique, compared to military intervention, is that it requires a relatively low expenditure of resources to achieve its goals.
Shoigu argued that this scheme has been used in a wide range of cases, including Serbia, Libya, and Syria—all cases where political interference by the West transitioned into military action. In 2014, the same scheme was followed in Ukraine, where anti-regime protests over several months transformed into a civil war, and in Venezuela, where the so-called democratic opposition is supposedly organized by the United States. While Western readers may find the lumping together of uprisings as disparate as those in Serbia in 2000, Syria in 2011, and Venezuela in 2014 hard to swallow, from the Russian point of view, they all share the common thread of occurring in countries that had governments that were opposed to the United States. Although uprisings in countries whose governments were close to the United States, such as Kyrgyzstan in 2010 and Egypt and Bahrain in 2011, are harder to explain, such inconsistencies do not appear to trouble the Russian government.
Furthermore, while Russian discussion of the destabilizing role of color revolutions usually portrays U.S. actions as taking place around the world, there is a clear perception that Russia is one of the main targets. This drives fear that unrest in the post-Soviet region may be a wedge for the United States to force regime change in Russia itself.
EXPLORE the palm-fringed bays of Port Blair, the capital of the Indian-owned Andaman and Nicobar islands, and intriguing sights appear. On one islet are the ghostly remains of a Victorian-era British settlement, its barracks, ballroom and Presbyterian church strangled by monstrous banyan trees. On another shore sits the headquarters of India’s only three-service—army, air and navy—military command. At a nearby wharf warships form a line, white ensigns flapping. A dry dock lies moored out in the harbour as a frigate steams out into the Bay of Bengal.
India had long neglected its island outpost close to mainland South-East Asia. Populated for thousands of years by indigenous tribes, the Andamans were used as a penal colony by the British until the Japanese invasion in 1942. After independence, India treated the Andamans as a remote backwater, too costly to supply or defend. The country’s military planners mostly faced west, to Pakistan.
Attitudes are changing. India increasingly looks east, whether hoping for trade or fretting about China’s military heft. In the Himalayas China has built roads, railways and other infrastructure along a 3,380-kilometre (2,100-mile) disputed border. India’s prime minister, Narendra Modi, says his country must build up there too. He will discuss the border with Xi Jinping, China’s president, who will visit India for three days from September 17th. Whatever progress he might make, India is at a strategic disadvantage in the Himalayas, since China looks down on it from the high Tibetan plateau. To compensate, Indian strategists seek advantages elsewhere.
That means bolstering strength at sea. A rising share of India’s growing military budget is being passed to the Indian navy. Three years ago it got just $4.2 billion; this year it has $6.2 billion, or nearly a fifth of total military spending. The navy is reportedly moving vessels and men from its western to its eastern command, which is said to include five guided-missile destroyers, three stealth frigates and a nuclear submarine. An aircraft-carrier is to come later. In the Andaman command a fleet of 15 vessels will expand to 32 in eight years. The army presence will also double, to 6,000.
Those in charge in Port Blair are natural disciples of those late-19th-century strategists who argued that geography and sea power are destiny.
Kang et al
Abstract:Here we describe a blood-cleansing device for sepsis therapy inspired by the spleen, which can continuously remove pathogens and toxins from blood without first identifying the infectious agent. Blood flowing from an infected individual is mixed with magnetic nanobeads coated with an engineered human opsonin—mannose-binding lectin (MBL)—that captures a broad range of pathogens and toxins without activating complement factors or coagulation. Magnets pull the opsonin-bound pathogens and toxins from the blood; the cleansed blood is then returned back to the individual. The biospleen efficiently removes multiple Gram-negative and Gram-positive bacteria, fungi and endotoxins from whole human blood flowing through a single biospleen unit at up to 1.25 liters per h in vitro. In rats infected with Staphylococcus aureus or Escherichia coli, the biospleen cleared >90% of bacteria from blood, reduced pathogen and immune cell infiltration in multiple organs and decreased inflammatory cytokine levels. In a model of endotoxemic shock, the biospleen increased survival rates after a 5-h treatment.
Bitcoin has continued its uncharacteristic streak of stability over the weekend, with its price never straying far from $478 (£294, €370).
Most other major cryptocurrencies have followed in the example set by bitcoin, as litecoin, peercoin, darkcoin and namecoin all shifted by less than 2% in value since Friday.
The only big player to see any significant movement was dogecoin, which saw its market capitalisation surge to £40m.
An Israeli company that spent a decade developing an autonomous, unmanned vertical takeoff and landing craft utilizing internal lift rotors says its first prototype is now going through flight tests and it’s at work on a second prototype.
Called the AirMule, the rotorcraft is envisioned for use as an unmanned transport – ferrying supplies into a combat zone or taking out wounded – operating in areas where helicopters and fixed-wing planes cannot.
Defense Tech first came across this work-in progress in 2009, when Urban Aeronautics Ltd. of Israel was preparing to demonstrate flight tests using a smaller, electrically-driven model to validate the basic technology. It now has a full-scale version being put through its paces.
Tactical Robotics Ltd., the UA subsidiary now handling development of the AirMule, says the vehicle will weigh 1,700 lbs, carry a payload of 1,400 pounds and fly at a maximum altitude of 12,000 feet. It will also make speeds of about 112 miles per hour.
The head of Air Force Special Operations Command says he is in the market for a directed energy beam weapon and plans to look at acquisitions possibilities as part of the 2017 defense budget.
Such a weapon could be used to knock out communications and power stations without the devastation and loss of life caused by bombs, rockets and missiles — something Air Force Lt. Gen. Bradley Heithold said was on the mind of many who lived through Operation Just Cause in Panama in 1989.
The operation to grab one-time U.S. ally and Panamanian strongman Manuel Noriega resulted in hundreds of civilian casualties.
“All we really had were kinetic rounds coming out of the airplane and really what you were trying to do was dismantle the Panamanian defense forces, wall them off and do the mission we had in hand,” said Heithold at a meeting with reporters Monday during the 2014 Air & Space Conference in Washington.
There are capabilities already being put to him, he said, but the timing and perhaps the technology still is not right.
“I’m a fan of looking at directed energy weapons, more of a fan of non-lethal directed energy weapons, so I’ve always kept [planning] space on my AC-130s for them,” he said. His 1998 paper suggested taking out the 20mm gun and replacing it with a directed energy weapon, but the technology at the time required a space the size of a small conference room.
The Air Force plans to award a contract to build its new bomber to a single vendor by next spring or summer as part of its ongoing effort to engineer a stealthy long range bomber that can evade advanced air defenses, service leaders said Sept. 15 at the Air Force Association Air and Space Conference at National Harbor, Maryland.
“We’re about ready to enter into the next phase of the bomber. We’ve spent the last couple of years refining the requirements and maturing the technology. Within the next year we will down-select to one contractor and then start the heavy lifting of building the first bomber and testing,” Lt. Gen. Ellen Pawlikowski, military deputy for Air Force acquisition, told Military.com in an interview.
The new Long-Range Strike Bomber program, or LRS-B, plans to have new planes in the fleet by the mid-2020s. The Air Force ultimately plans to acquire as many as 80 to 100 new bombers for a price of roughly $550 million per plane, she added.
The Air Force has made the Long Range Strike Bomber one of its top priorities and successfully protected it from the cuts other weapons programs have sustained.
Investigation of Late Pleistocene and Early Holocene palaeoenvironmental change at El Mirón cave (Cantabria, Spain): Insights from carbon and nitrogen isotope analyses of red deer
Authors:
Stevens et al
Abstract:
El Mirón Cave was occupied by humans for over 40,000 years. Evidence of Late Mousterian, Gravettian, Solutrean, Magdalenian, Azilian, Mesolithic, Neolithic, Chalcolithic, Bronze Age and Mediaeval occupations has been found in the cave. Understanding the local environmental conditions during the occupations is crucial for gaining an insight into the lifeways of El Mirón's inhabitants as they relied on the surrounding region and its natural resources for their subsistence. 170 bones of hunted red deer recovered from the cave were sampled for carbon and nitrogen stable isotope analyses with the aim of reconstructing the palaeoenvironment and palaeoclimate during the human occupation. The results show that the surrounding landscape underwent considerable environmental change during the Late Pleistocene and Early to Mid-Holocene. Shifts in δ13C values between the Last Glacial Maximum, Heinrich stadial 1, Heinrich event 1, the Late-glacial interstadial and the onset of the Holocene are likely to reflect changes in water availability and temperature. Deer δ15N generally increased over time indicating the regeneration of soil biological activity and nitrogen cycling, which was temporarily halted during the Younger Dryas. Comparison of the El Mirón results with those of 300 deer from other regions of Europe shows geographical variations in the timing and magnitude of the variation in δ13C and δ15N values. This variation tracks local climate (temperature and water availability) and environmental (vegetation and forest development) changes.
Keeping upright in a low-gravity environment is not easy, and NASA documents abound with examples of astronauts falling on the lunar surface. Now, a new study by an international team of researchers led by York University professors Laurence Harris and Michael Jenkin, published today in PLOS ONE, suggests that the reason for all these moon mishaps might be because its gravity isn't sufficient to provide astronauts with unambiguous information on which way is "up".
"The perception of the relative orientation of oneself and the world is important not only to balance, but also for many other aspects of perception including recognizing faces and objects and predicting how objects are going to behave when dropped or thrown," says Harris. "Misinterpreting which way is up can lead to perceptual errors and threaten balance if a person uses an incorrect reference point to stabilize themselves."
Using a short-arm centrifuge provided by the European Space Agency, the international team simulated gravitational fields of different strengths, and used a York-invented perceptual test to measure the effectiveness of gravity in determining the perception of up. The team found that the threshold level of gravity needed to just influence a person's orientation judgment was about 15 per cent of the level found on Earth – very close to that on the moon.
The team also found that Martian gravity, at 38 per cent of that on Earth, should be sufficient for astronauts to orient themselves and maintain balance on any future manned missions to Mars.
