Friday, July 28, 2017

Unique Wheat Discovery in Bronze Age Lunch Box


Container found in the Swiss Alps leads researchers to new analysis method

In a wooden container found in the Bernese Alps in 2012, a researcher from the Max Planck Institute for the Science of Human History, together with an international research team, has discovered the remains of ancient wheat dating back to the Bronze Age. The find is significant for two reasons: Firstly, there have been very few clues to indicate how cereals were used and spread during this period. Secondly, the scientists discovered a new way for molecular identification of cereal grains in archaeological artefacts. This opens up new possibilities for research.

At the bottom of a Bronze Age wooden vessel, researchers discovered residues of cereal grains (central dark spot). Additionally, parts of a bent rim were found, indicating that the container must have been about 10 centimetres high. More fragments, perhaps parts of the top, still need to be examined.

© Archaeological Service of the Canton of Bern, Badri Redha

Melting glaciers are increasingly revealing finds from the past. They are not always as spectacular as “Ötzi”, the glacier mummy who lived during the late-Neolithic Age, and was discovered by hikers in the Ötztal Alps in 1991. However, even less sensational discoveries of perishable materials such as fabrics, leather, wood and other plant-based remains that survive for hundreds or even thousands of years in ice, open up new perspectives on the past for archaeologists.

A Bronze Age box

In 2012, the ice near the Lötschenpass, at 2,690 metres in the Bernese Alps, revealed an extraordinary wooden vessel. The round container measures approx. 20 cm in diameter. The base consists of Swiss pine, the bent rim is made of willow; both sections were sewn together with splint twigs of European larch. Radiocarbon dating showed that the vessel is around 4,000 years old and thus dates back to the early Bronze Age.

Traces found on the upper surface of the container were of particular interest to the research team, which included Jessica Hendy from the Max Planck Institute for the Science of Human History: a microscopic examination revealed a residue of barley, spelt and emmer, including pericarp and glumes. Cereal grains are frequently found at Bronze Age cave sites. However, vessels containing grains or their residues were have never been reported before. These are of particular interest to researchers, as they provide clues as to how the cereal was used at that time.
Traders, herders or hunters?

The scientists can only guess the story behind the box found at the Lötschenpass. They know that some alpine valleys in the area were settled during the Bronze Age. A large number of Early Bronze age graves in neighbouring Valais show that the valley was not only settled but people imported goods from north and south of the Alps. The vessel could be linked with either trading connections or seasonal movements from lowland areas to upland pastures as part of the pastoral economy. Hunting could also explain the requirement to access such rocky and glaciated areas of the high Alps.

Francesco Carrer from Newcastle University said: “This evidence sheds new light on life in prehistoric alpine communities, and on their relationship with the extreme high altitudes. People travelling across the alpine passes were carrying food for their journey, like current hikers do. This new research contributed to understanding which food they considered the most suitable for their trips across the Alps.”

Substances similar to modern-day whole grain products

The scientists actually expected to find milk residues in the vessel, for example a porridge type meal. They therefore performed a molecular analysis on the discovery. They did not find any evidence of milk but instead discovered alkylresorcinols, which are found in modern-day whole grain products.

André Colonese of the University of York, lead author of the study, states, “These phenolic lipids have never been reported before in an archaeological artefact, but are abundant in the bran of wheat and rye cereals. One of the greatest challenges of lipid analysis in archaeology has been finding biomarkers for plants. There are only a few and they do not preserve very well in ancient artefacts. You can imagine the relevance of this study. It really is very exciting.”

The new method opens up possibilities for discovering how Bronze Age people actually used cereals. As a next step, the scientists plan to look for these biomarkers in ancient ceramic artefacts.

“Detecting a molecular marker for cereals also has widespread implications for studying early farming. It enables us to piece together when and where this important food crop spread through Europe,” adds Jessica Hendy, from the Max Planck Institute for the Science of Human History.

The study conducted on the Bronze Age box involved collaboration between the University of York, the Max Planck Institute for the Science of Human History, the Archaeological Service of the Canton of Bern, the University of Basel, the University of Copenhagen, Newcastle University and the University of Oxford.







Contacts and sources:
Dr. Jessica Hendy
Max Planck Institute for the Science of Human History, Jena

Astrophysicists Map Out the Light Energy Contained within the Milky Way

For the first time, a team of scientists have calculated the distribution of all light energy contained within the Milky Way, which will provide new insight into the make-up of our galaxy and how stars in spiral galaxies such as ours form. The study is published in the journal Monthly Notices of the Royal Astronomical Society.

This research, conducted by astrophysicists at the University of Central Lancashire (UCLan), in collaboration with colleagues from the Max Planck Institute for Nuclear Physics in Heidelberg, Germany and from the Astronomical Institute of the Romanian Academy, also shows how the stellar photons, or stellar light, within the Milky Way control the production of the highest energy photons in the Universe, the gamma-rays. This was made possible using a novel method involving computer calculations that track the destiny of all photons in the galaxy, including the photons that are emitted by interstellar dust, as heat radiation.

An all-sky image of the Milky Way, as observed by the Planck Space Observatory in infrared. The data contained in this image were used in this research and were essential in calculating the distribution of the light energy of our Galaxy.
Credit: ESA / HFI / LFI consortia. 

Previous attempts to derive the distribution of all light in the Milky Way based on star counts have failed to account for the all-sky images of the Milky Way, including recent images provided by the European Space Agency's Planck Space Observatory, which map out heat radiation or infrared light.

Lead author Prof Cristina Popescu from the University of Central Lancashire, said: "We have not only determined the distribution of light energy in the Milky Way, but also made predictions for the stellar and interstellar dust content of the Milky Way.”

By tracking all stellar photons and making predictions for how the Milky Way should appear in ultraviolet, visual and heat radiation, scientists have been able to calculate a complete picture of how stellar light is distributed throughout our Galaxy. An understanding of these processes is a crucial step towards gaining a complete picture of our Galaxy and its history.

The modelling of the distribution of light in the Milky Way follows on from previous research that Prof Popescu and Dr Richard Tuffs from the Max Planck Institute for Nuclear Physics conducted on modelling the stellar light from other galaxies, where the observer has an outside view.

Commenting on the research, Dr Tuffs, one of the co-authors of the paper, said: “It has to be noted that looking at galaxies from outside is a much easier task than looking from inside, as in the case of our Galaxy.”

Scientists have also been able to show how the stellar light within our Galaxy affects the production of gamma-ray photons through interactions with cosmic rays. Cosmic rays are high-energy electrons and protons that control star and planet formation and the processes governing galactic evolution. They promote chemical reactions in interstellar space, leading to the formation of complex and ultimately life-critical molecules.

Dr Tuffs added: "Working backwards through the chain of interactions and propagations, one can work out the original source of the cosmic rays."

The research, funded by the Leverhulme Trust, was strongly interdisciplinary, bringing together optical and infrared astrophysics and astro-particle physics. Prof Popescu notes: “We had developed some of our computational programs before this research started, in the context of modelling spiral galaxies, and we need to thank the UK's Science and Technology Facility Council (STFC) for their support in the development of these codes. This research would also not have been possible without the support of the Leverhulme Trust, which is greatly acknowledged.”



Contacts and sources:
Sophie Roberts
thisismc2 (on behalf of UCLan)

Dr Morgan Hollis
Royal Astronomical Society

Analysis of Ancient Teeth Suggests Neolithic Cattle Grazed at Home and Away

An international team of researchers has shown in unprecedented detail that prehistoric farmers took their animals away from permanent settlements to graze in more fertile areas - probably because of high demand for land locally.

Analysis of strontium isotopes in teeth of Neolithic cattle suggests that early Europeans used specialized strategies to manage herding, according to a study by the universities of Basel, Southampton, Bristol and the The Curt-Engelhorn-Centre for Archaeometry. It's thought these strategies helped to maintain larger herds, and may have contributed to increased social inequality.

Findings are published in the open-access journal PLOS ONE.

Archaeologist Professor Alistair Pike, from the University of Southampton, who worked on the study, explained: "Over the course of the Neolithic period, cattle became increasingly important for milk, manure and animal power rather than just for meat. This led to larger herds, and greater demand for grazing resources. To accommodate these larger herds, it has always been speculated that farmers needed to find grazing grounds further away from permanent settlements - however, until our study, there has been little direct evidence for this."

Jaw from Neolithic cattle
Credit C Gerling University of Basel

To reconstruct the movement of cattle and explore how the herd may have been managed, the researchers analysed strontium isotopes in 39 molar teeth from 25 cattle from the Neolithic settlement of Arbon Bleiche 3, in what is now Switzerland. The settlement, which was occupied for just 15 years in the 34th century BC, had 27 houses, and cattle from 12 of these were sampled.

Strontium isotopes are found in bones and teeth and its geochemical signature can be used to infer geographic location. Scientists can relate findings from their analyses to the isotopic composition of local soils and plants (which can vary over relatively short distances), thus, in this case, indicating different areas the cattle may have been led to for grazing.

The researchers found that molar teeth from the cattle in this study had three strontium patterns, which likely reflected three different herding strategies. The first pattern was consistent with the local strontium baseline, suggesting cattle were grazing locally; the second pattern was a mix of local and non-local strontium signatures, suggesting seasonal movement; and the third was mostly non-local strontium signatures, suggesting year-round herding away from the main settlement.

Alpine cattle in the Canton of Schwyz Switzerland

 Credit C Gerling University of Basel

Commenting on the archaeological site in Switzerland, Professor Pike said: "A
]rbon Bleiche 3 at Lake Constance gave us an unprecedented opportunity to study how cattle were managed. Most archaeological sites span many generations or centuries, but because this was only occupied for 15 years, we can be pretty sure the cattle were all living and grazing at about the same time.. This allowed us to reconstruct the movement of individual herds and get a far more detailed picture of how these livestock were being moved."

In addition, the researchers found that the three herding strategies were not uniformly represented in various areas of the settlement. This suggests differential access to the most favorable grazing grounds, which could have contributed to social inequalities between groups or households.

In summary, Professor Pike said: "We are very excited about these results. They show that cattle herding intensified to the extent that local grazing had reached capacity and cattle needed to be taken further afield. Not all households would have had access to the best grazing, so the increasing importance of cattle may have increased the socioeconomic differentiation in the community. This is something that is more widely visible later, during the European Bronze Age, with the tradition of burying the dead with status items - so it is particularly interesting to be able to see something similar in an earlier period."



Contacts and sources:
University of Southampton

Citation:
High-resolution isotopic evidence of specialised cattle herding in the European Neolithichttp://journals.plos.org/plosone/article?id=10.1371/journal.pone.0180164


Canadian Sapphires Fit for a Queen Unearthed by UBC Research



New research from UBC mineralogists could make it easier to find high-quality Canadian sapphires, the same sparkling blue gems that adorn Queen Elizabeth II’s Sapphire Jubilee Snowflake Brooch.

The so-called Beluga sapphires were discovered near Kimmirut, Baffin Island, Nunavut by brothers Nowdluk and Seemeega Aqpik in 2002. The location is Canada’s only known deposit of sapphires. The gems form the basis of the ceremonial brooch given to the Queen last week by Canada’s Governor General David Johnston.


Sapphire crystal, 3.6 cm, and gemstone from Kimmirut. 
Add caption
Photo courtesy of B.S. Wilson.


“These occurrences are the first reported sapphires hosted in this type of marble-related deposit,” says Philippe Belley, a graduate student at the University of British Columbia. “We’ve discovered that it takes a fairly specific sequence of pressure and temperature events to create these gems. It’s essentially a recipe.”

Belley, UBC mineralogist Lee Groat, and colleagues, outline the findings in the July issue of the Canadian Mineralogist, where they discovered the unique recipe of pressure and temperature events from Earth’s history that were required to form sapphires in this area.

The researchers compared this information to regional data to pinpoint the most promising areas for sapphire exploration. Those areas are expected to occur near a fault that separates the Lake Harbour Group and Narsajuaq terranes. A terrane is a fault-bounded area or region with a distinctive stratigraphy, structure, and geological history.

“This research has enabled us to identify the areas of greatest potential for Kimmirut-type sapphire deposits in southern Baffin Island, which will facilitate gemstone exploration in this part of the Arctic,” says Groat, a UBC expert on gem deposits. “But it’s also a deposit model that can be applied to exploration worldwide.”

Sapphires are usually cut and polished into gemstones for jewelry. The Beluga sapphires are typically a striking blue, but are sometimes yellow or colourless. The Queen’s Sapphire Jubilee Snowflake Brooch consists of 48 Beluga sapphires, along with 400 diamonds from northern Canada, all set in Canadian white gold. Sapphires range in price from US$200 to $2,000 per carat.



Contacts and sources:
University of British Columbia

Study available at: http://www.canmin.org/content/55/4/669.abstract





Attached files


"Origin of Scapolite-Hosted Sapphire (Corundum) Near Kimmirut, Baffin Island, Nunavut, Canada";
Philippe M. Belley, Tashia J. Dzikowski, Andrew Fagan, Jan Cempíre‡, Lee A. Groat and James K. Mortensen;
doi: 10.3749/canmin.1700018
Can Mineral July 1, 2017 vol. 55 no. 4 669-699

‘Omnipresent’ Effects of Human Impact on England’s Landscape Revealed

‘Omnipresent’ signs demonstrating the effects of human impact on England’s landscape have been revealed by researchers from the University of Leicester.

Concrete structures forming a new, human-made rock type; ash particles in the landscape; and plastic debris are just a few of the new materials irreversibly changing England’s landscape and providing evidence of the effects of the Anthropocene, the research suggests.

Plastic planet 

Credit:  University of Leicester

The research, which is published in the journal Proceedings of the Geologists’ Association, has been conducted by geologists Jan Zalasiewicz, Colin Waters, Mark Williams and Ian Wilkinson at the University of Leicester, working together with zoologist David Aldridge at Cambridge University, as part of a major review of the geological history of England organised by the Geologists’ Association.

Professor Jan Zalasiewicz, from the University of Leicester’s Department of Geology, said: “We are realising that the Anthropocene is a phenomenon on a massive scale – it is the transformation of our planet by human impact, in ways that have no precedent in the 4.54 billion years of Earth history. Our paper explores how these changes appear when seen locally, on a more modest scale, amid the familiar landscapes of England.”


Dreissena polymorpha from the River Thames tideway at Teddington 
Credit David Aldridge, University of Cambridge


Professor Mark Williams, from the University of Leicester’s Department of Geology, said: “These changes taken together are now virtually omnipresent as the mark of the English Anthropocene. They are only a small part of the Anthropocene changes that have taken place globally. But, to see them on one’s own doorstep brings home the sheer scale of these planetary changes – and the realization that geological change does not recognize national boundaries.”

The Anthropocene - the concept that humans have so transformed geological processes at the Earth’s surface that we are living in a new epoch - was formulated by Nobel Laureate Paul Crutzen in 2000.

The research suggests that some of the changes surround us in the most obvious and visible way, though we rarely think of them as geology.

Examples include the concrete structures of our cities, which have almost all been built since the Second World War, and are just one small part of steep rise in the global prominence of this new, human-made rock type.

Other changes need a microscope to see, such as fly ash particles that have sprinkled over the landscape – a fossil signal of the smoke that belched out during industrialization – or the skeletons of tiny algae in ponds and lakes across England, the types of which dramatically changed as the waters then acidified too.

Larger future fossils include the shells of highly successful biological invaders such as the zebra mussel and Asian clam, which now dominate large parts of the Thames and other river systems.

There are subterranean rock changes too, as coal mines, metro systems and boreholes have riddled the subsurface with holes and caverns.

The research also shows how the chemistry of soils and sediments has been marked by an influx of lead, copper and cadmium pollution – and by plastic debris, pesticide residues and radioactive plutonium.




 Contacts and sources:
 University of Leicester

Citation:  'The stratigraphical signature of the Anthropocene in England and its wider context', has been published in the journal Proceedings of the Geologists' Association and is available here: http://www.sciencedirect.com/science/article/pii/S0016787817300895
Jan Zalasiewicza, Colin Watersa, Mark Williamsa,David C. Aldridgeb, Ian P. Wilkinso

August 21 Total Solar Eclipse Is First to Cross the U.S. in Nearly a Century

Graphic showing the positions of Earth, moon, and sun during a total solar eclipse.

Thursday, July 27, 2017

Large-Mouthed Fish Was Top Predator after Mass Extinction



The food chains recovered more rapidly than previously assumed after Earth’s most devastating mass extinction event about 252 million years ago as demonstrated by the fossilized skull of a large predatory fish called Birgeria americana discovered by paleontologists from the University of Zurich in the desert of Nevada.

Illustration:  Possible look of the newly discovered predatory fish species Birgeria americana with the fossil oft he skull shown at bottom right
 Artwork: Nadine Bösch


The most catastrophic mass extinction on Earth took place about 252 million years ago – at the boundary between the Permian and Triassic geological periods. Up to 90 percent of the marine species of that time were annihilated. Worldwide biodiversity then recovered in several phases throughout a period of about five million years. Until now, paleontologists have assumed that the first predators at the top of the food chain did not appear until the Middle Triassic epoch about 247 to 235 million years ago.

Unexpected find of a large predatory fish

Swiss and U.S. American researchers led by the Paleontological Institute and Museum of the University of Zurich have discovered the fossil remains of one of the earliest large-sized predatory fishes of the Triassic period: an approximately 1.8-meter-long primitive bony fish with long jaws and sharp teeth. This fish belongs to a previously unknown species called Birgeria americana. This predator occupied the sea that once covered present-day Nevada and the surrounding states already one million years after the mass extinction.

Triassic "Jaws“

In the United States, almost no vertebrate fossils from the Early Triassic epoch (252 to 247 million years ago) have been scientifically described until now. “The surprising find from Elko County in northeastern Nevada is one of the most completely preserved vertebrate remains from this time period ever discovered in the United States,” emphasizes Carlo Romano, lead author of the study. The fossil in question is a 26-centimeter-long partial skull of a fierce predator, as evidenced by three parallel rows of sharp teeth up to 2 centimeters long along the jaw margins, as well as several smaller teeth inside the mouth.

The 26 cm long fossil preserving the right side of the skull of Birgeria americana.
Image: UZH

Birgeria hunted similarly to the extant great white shark: the prey fish were pursued and bitten, then swallowed whole. Species of Birgeria existed worldwide. The most recent discovery is the earliest example of a large-sized Birgeria species, about one and a half times longer than geologically older relatives.

Predators appeared earlier than assumed

According to earlier studies, marine food chains were shortened after the mass extinction event and recovered only slowly and stepwise. In addition, researchers assumed that the ancient equatorial regions were too hot for vertebrates to live during the Early Triassic. Finds such as the newly discovered Birgeria species and the fossils of other vertebrates now show that so-called apex predators (animals at the very top of the food chain) already lived early after the mass extinction. The existence of bony fish close to the equator ‒ where Nevada was located during the Early Triassic ‒ indicates that the temperature of the sea was a maximum of 36°C. The eggs of today’s bony fish can no longer develop normally at constant temperatures above 36°C.

“The vertebrates from Nevada show that previous interpretations of past biotic crises and associated global changes were too simplistic,” Carlo Romano says. Despite the severity of the extinctions of that time and intense climatic changes, the food webs were able to redevelop faster than previously assumed.


Contacts and sources:
Dr. Carlo Romano
University of Zurich

Citation: Carlo Romano, James F. Jenks, Romain Jattiot, Torsten M. Scheyer, Kevin G. Bylund, and Hugo Bucher. Marine Early Triassic Actinopterygii from Elko County (Nevada, USA): implications for the Smithian equatorial vertebrate eclipse. Journal of Paleontology. 19. July 2017. DOI: 10.1017/jpa.2017.36

Identifying Prehistoric Social Network Dynamics with Modern Algorithms

In the first ever archaeological study of its kind, two researchers have combined the chemical analyses of dozens of the world’s earliest copper artefacts and modularity approach in order to identify prehistoric networks of co-operation during the early development of European metalmaking. This study has led them one step further: the communities that co-operated the most largely belonged to the same archaeological culture, thus revealing a novel method for an independent evaluation of the archaeological record.

Archaeological systematics, particularly in prehistory, use the accumulation of similar material traits or dwelling forms in archaeological sites to designate distinctive ‘archaeological cultures’; however, what these expressions of similarity represent and at what resolution remain a major problem in the field of archaeology.

Modularity analysis reveals three densely connected modules/communities that produced and exchanged copper in the Balkans between c. 6200 BC and c. 3200 BC. They are also significantly correlated with the distribution of archaeological cultures at the time



Credit: Cambridge University


The study, published this week in the Journal of Complex Networks, takes an alternative approach by measuring the strength of links between archaeological sites instead and produces pioneering models of human interaction and cooperation that can be evaluated independently of established archaeological systematics. It focuses on a comprehensive archaeological database of copper artefacts from the Balkans, dated from c. 6200 BC to 3200 BC – the first 3,000 years of known copper mineral and metal use in Europe.

Chemical composition of these artefacts is the sole information used for modularity analysis, hence isolated from any archaeological and spatiotemporal information. The results are, however, archaeologically and spatiotemporally meaningful for the evolution of the world’s earliest copper supply network.

Dr Jelena Grujić, physicist from the Vrije University in Brussels, explains the novelty of this method for archaeological research: “Although there are a few approaches that archaeologists use to infer models of circulation of metals in the past, and hence indicate prehistoric economic and social ties, the modularity analysis offers for the first time an option to test the significance of our results, and hence a method that is mathematically reliable and replicable”.

Dr Miljana Radivojević, lead author and researcher at the McDonald Institute for Archaeological Research, University of Cambridge commented, “Being able to infer social groups with strong spatial and temporal significance in archaeological data using this network property is a real game changer. This study is major step towards evaluating technological, economic and social phenomena in the human past – anywhere”.

The original article is accessible here





Contacts and sources:
Laure Bonner
Cambridge University

Analysis of Ancient DNA Recreates the Genetic History of Portugal and Spain


The genomes of individuals who lived on the Iberian Peninsula in the Bronze Age had minor genetic input from Steppe invaders, suggesting that these migrations played a smaller role in the genetic makeup and culture of Iberian people, compared to other parts of Europe. Daniel Bradley and Rui Martiniano of Trinity College Dublin, in Ireland, and Ana Maria Silva of University of Coimbra, Portugal, report these findings July 27, 2017 in PLOS Genetics.

Between the Middle Neolithic (4200-3500 BC) and the Middle Bronze Age (1740-1430 BC), Central and Northern Europe received a massive influx of people from the Steppe regions of Eastern Europe and Asia. Archaeological digs in Iberia have uncovered changes in culture and funeral rituals during this time, but no one had looked at the genetic impact of these migrations in this part of Europe. Researchers sequenced the genomes of 14 individuals who lived in Portugal during the Neolithic and Bronze Ages and compared them to other ancient and modern genomes. 

 Archaeological remains of individual MC337 excavated from the site of Hipogeu de Monte Canelas I, Portugal, and analysed by the archaeologist Rui Parreira and the anthropologist Ana Maria Silva.
Credit: Rui Parreira

In contrast with other parts of Europe, they detected only subtle genetic changes between the Portuguese Neolithic and Bronze Age samples resulting from small-scale migration. However, these changes are more pronounced on the paternal lineage. "It was surprising to observe such a striking Y chromosome discontinuity between the Neolithic and the Bronze Age, such as would be consistent with a predominantly male-mediated genetic influx" says first author Rui Martiniano. Researchers also estimated height from the samples, based on relevant DNA sequences, and found that genetic input from Neolithic migrants decreased the height of Europeans, which subsequently increased steadily through later generations.

The study finds that migration into the Iberian Peninsula occurred on a much smaller scale compared to the Steppe invasions in Northern, Central and Northwestern Europe, which likely has implications for the spread of language, culture and technology. These findings may provide an explanation for why Iberia harbors a pre-Indo-European language, called Euskera, spoken in the Basque region along the border of Spain and France. It has been suggested that Indo-European spread with migrations through Europe from the Steppe heartland; a model that fits these results.

Daniel Bradley says "Unlike further north, a mix of earlier tongues and Indo-European languages persist until the dawn of Iberian history, a pattern that resonates with the real but limited influx of migrants around the Bronze Age."

 
Contacts and sources:
PLoS


Citation: Martiniano R, Cassidy LM, Ó'Maoldúin R, McLaughlin R, Silva NM, Manco L, et al. (2017) The population genomics of archaeological transition in west Iberia: Investigation of ancient substructure using imputation and haplotype-based methods. PLoS Genet 13(7): e1006852. https://doi.org/10.1371/journal.pgen.1006852  http://journals.plos.org/plosgenetics/article?id=10.1371/journal.pgen.1006852



Biblical Canaanites Are Survived by Lebanese People Today Says DNA Study

In the most recent whole-genome study of ancient remains from the Near East, Wellcome Trust Sanger Institute scientists and their collaborators sequenced the entire genomes of 4,000-year-old Canaanite individuals who inhabited the region during the Bronze Age, and compared these to other ancient and present-day populations. 

The results, published today (27 July) in the American Journal of Human Genetics suggest that present-day Lebanese are direct descendants of the ancient Canaanites.

The Near East is often described as the cradle of civilisation. The Bronze Age Canaanites, later known as the Phoenicians, introduced many aspects of society that we know today - they created the first alphabet, established colonies throughout the Mediterranean and were mentioned several times in the Bible.

Skeleton from the excavation at Sidon. 
Bodyimageskeleton.png
Credit: Dr Claude Doumet-Serhal

However, historical records of the Canaanites are limited. They were mentioned in ancient Greek and Egyptian texts, and the Bible which reports widespread destruction of Canaanite settlements and annihilation of the communities. Experts have long debated who the Canaanites were genetically, what happened to them, who their ancestors were and if they had any descendants today.

In the first study of its kind, scientists have uncovered the genetics of the Canaanite people and a firm link with people living in Lebanon today. The team discovered that more than 90 per cent of present-day Lebanese ancestry is likely to be from the Canaanites, with an additional small proportion of ancestry coming from a different Eurasian population. Researchers estimate that new Eurasian people mixed with the Canaanite population about 2,200 to 3,800 years ago at a time wen there were many conquests of the region from outside.

The analysis of ancient DNA also revealed that the Canaanites themselves were a mixture of local people who settled in farming villages during the Neolithic period and eastern migrants who arrived in the area around 5,000 years ago.

In the study, researchers sequenced whole genomes of five Canaanite individuals who lived 4,000 years ago in a city known as Sidon in present-day Lebanon. Scientists also sequenced the genomes of 99 present-day Lebanese and analysed the genetic relationship between the ancient Canaanites and modern Lebanese.

Dr Marc Haber, first author from the Wellcome Trust Sanger Institute, said: "It was a pleasant surprise to be able to extract and analyse DNA from 4,000-year-old human remains found in a hot environment, which is not known for preserving DNA well. We overcame this challenge by taking samples from the petrous bone in the skull, which is a very tough bone with a high density of ancient DNA. This method of extraction combined with the lowering costs of whole genome sequencing made this study possible."

Dr Claude Doumet-Serhal, co-author and Director of the Sidon excavation site* in Lebanon, said: "For the first time we have genetic evidence for substantial continuity in the region, from the Bronze Age Canaanite population through to the present day. These results agree with the continuity seen by archaeologists. Collaborations between archaeologists and geneticists greatly enrich both fields of study and can answer questions about ancestry in ways that experts in neither field can answer alone."

Dr Chris Tyler-Smith, lead author from the Wellcome Trust Sanger Institute, said: "Genetic studies using ancient DNA can expand our understanding of history, and answer questions about the likely origins and descendants of enigmatic populations like the Canaanites, who left few written records themselves. Now we would like to investigate the earlier and later genetic history of the Near East, and how it relates to the surrounding regions."




Contacts and sources:
Emily Mobley
Wellcome Trust Sanger Institute
Sidon excavation site  http://www.sidonexcavation.com

Citation: Marc Haber et al. (2017) Continuity and admixture in the last five millennia of Levantine history from ancient Canaanite and present-day Lebanese genome sequences. American Journal of Human Genetics. DOI: 10.1016/j.ajhg.2017.06.013

Milky Way's Origins Are Not What They Seem

In a first-of-its-kind analysis, Northwestern University astrophysicists have discovered that, contrary to previously standard lore, up to half of the matter in our Milky Way galaxy may come from distant galaxies. As a result, each one of us may be made in part from extragalactic matter.

Using supercomputer simulations, the research team found a major and unexpected new mode for how galaxies, including our own Milky Way, acquired their matter: intergalactic transfer. The simulations show that supernova explosions eject copious amounts of gas from galaxies, which causes atoms to be transported from one galaxy to another via powerful galactic winds. Intergalactic transfer is a newly identified phenomenon, which simulations indicate will be critical for understanding how galaxies evolve.

A Milky Way-like galaxy (Messier 101): A close-up view of the Messier 101 galaxy, which is a spiral galaxy similar to the Milky Way galaxy. The Messier 101 has a pancake-like shape that we view face-on. This perspective shows off the spiral structure that gives it the nickname the "Pinwheel Galaxy."A Milky Way-like galaxy
Credit:  NASA 

“Given how much of the matter out of which we formed may have come from other galaxies, we could consider ourselves space travelers or extragalactic immigrants,” said Daniel Anglés-Alcázar, a postdoctoral fellow in Northwestern’s astrophysics center, CIERA (Center for Interdisciplinary Exploration and Research in Astrophysics), who led the study. “It is likely that much of the Milky Way’s matter was in other galaxies before it was kicked out by a powerful wind, traveled across intergalactic space and eventually found its new home in the Milky Way.”

Galaxies are far apart from each other, so even though galactic winds propagate at several hundred kilometers per second, this process occurred over several billion years.

Professor Claude-André Faucher-Giguère and his research group, along with collaborators from the FIRE (“Feedback In Realistic Environments”) project, which he co-leads, had developed sophisticated numerical simulations that produced realistic 3-D models of galaxies, following a galaxy’s formation from just after the Big Bang to the present day. Anglés-Alcázar then developed state-of-the-art algorithms to mine this wealth of data and quantify how galaxies acquire matter from the universe.

Pair of nearby galaxies with possible intergalactic transfer: This image shows M81 (bottom right) and M82 (upper left), a pair of nearby galaxies where “intergalactic transfer” may be happening. Gas ejected by supernova explosions in M82 can travel through space and eventually contribute to the growth of M81.

Credit: Fred Herrmann, 2014, http://cs.astronomy.com/asy/m/galaxies/489483.aspx



The study, which required the equivalent of several million hours of continuous computing, will be published July 26 (July 27 in the U.K.) by the Monthly Notices of the Royal Astronomical Society.

“This study transforms our understanding of how galaxies formed from the Big Bang,” said Faucher-Giguère, a co-author of the study and assistant professor of physics and astronomy in the Weinberg College of Arts and Sciences.

“What this new mode implies is that up to one-half of the atoms around us -- including in the solar system, on Earth and in each one of us -- comes not from our own galaxy but from other galaxies, up to one million light years away,” he said.

By tracking in detail the complex flows of matter in the simulations, the research team found that gas flows from smaller galaxies to larger galaxies, such as the Milky Way, where the gas forms stars. This transfer of mass through galactic winds can account for up to 50 percent of matter in the larger galaxies.

“In our simulations, we were able to trace the origins of stars in Milky Way-like galaxies and determine if the star formed from matter endemic to the galaxy itself or if it formed instead from gas previously contained in another galaxy,” said Anglés-Alcázar, the study’s corresponding author.

In a galaxy, stars are bound together: a large collection of stars orbiting a common center of mass. After the Big Bang 14 billion years ago, the universe was filled with a uniform gas -- no stars, no galaxies. But there were tiny perturbations in the gas, and these started to grow by force of gravity, eventually forming stars and galaxies. After galaxies formed, each had its own identity.
'
Animation of intergalactic transfer of gas


“Our origins are much less local than we previously thought,” said Faucher-Giguère, a CIERA member. “This study gives us a sense of how things around us are connected to distant objects in the sky.”

The findings open a new line of research in understanding galaxy formation, the researchers say, and the prediction of intergalactic transfer can now be tested. The Northwestern team plans to collaborate with observational astronomers who are working with the Hubble Space Telescope and ground-based observatories to test the simulation predictions.

The research was supported by NASA, the National Science Foundation (NSF) and Northwestern’s CIERA. The simulations were run and analyzed using NSF’s Extreme Science and Engineering Discovery Environment supercomputing facilities, as well as Northwestern’s Quest high-performance computer cluster.

The study is titled “The Cosmic Baryon Cycle and Galaxy Mass Assembly in the FIRE Simulations.” In addition to Anglés-Alcázar and Faucher-Giguère, other authors include Dušan Kereš (University of California, San Diego), Philip F. Hopkins(Caltech), Eliot Quataert (University of California, Berkeley) and Norman Murray (Canadian Institute for Theoretical Astrophysics).

More information on the research can be found at Northwestern’s galaxy formation group website and on the FIRE project website.

 

Contacts and sources
Daniel Anglés-Alcázar / Claude-André Faucher-Giguère
Northwestern University

Nanotech Cooling Curtain Offers Alternative to Air Conditioners

Climate change is leading to ever higher temperatures and aridity in many areas, making efficient room cooling increasingly important. An ETH doctoral student at the Functional Materials Laboratory has developed an alternative to electrically powered air conditioning: a cooling curtain made of a porous triple-layer membrane.

It all began with a vague idea: “We thought it would be interesting to combine opposing functions in one material,” says Mario Stucki, a doctoral student at ETH Zurich’s Functional Materials Laboratory. He combined two layers of hydrophobic (water-repellent) polyurethane with a middle layer of hydrophilic (water-attracting) polymer. The resulting membrane feels dry, although it is saturated with water, and since the outer layers are covered with holes of about one micrometer in diameter, water can escape from the middle layer into the environment.

An alternative for heat-afflicted areas

Electricity savings at summer heat: Mario Stucki developed a new type of membrane that cools rooms.

Photograph: Peter Rüegg / ETH Zurich

When Stucki realized how well the water transport works across the various layers, he came up with the idea of the cooling curtain. “Water evaporation requires a lot of energy,” he says. “Heat is extracted from the air, it cools and at the same time humidifies the surrounding area.” Conventional humidifiers work in the same way – but they need a lot of power, whereas Stucki’s system is passive. “The sunlight that falls through a window on to the curtain provides enough energy for this type of air conditioning.”

Such curtains could be a real blessing in hot and arid regions. In 2015, people in the Arabian Peninsula endured a heatwave with temperatures of more than 50°C. Climate scientists forecast even higher temperatures and severe aridity for desert regions, which could lead to certain climate zones becoming uninhabitable. Cooling buildings and rooms is thus becoming increasingly essential, but it devours vast amounts of electricity. In the US, for example, about 15 percent of energy consumption can be attributed to air-conditioning equipment, and a huge amount of this energy comes from fossil fuels. The passive cooling curtain would be an environmentally and climate-friendly alternative.

Further development of an earlier innovation

Stucki attracted attention back in 2013 with his Master’s thesis at ETH Zurich, when he developed a new material for outdoor use in no time. In contrast to conventional functional textiles, it does not contain fluorine compounds, which are harmful to the environment and human health.

His current research makes use of that invention: he functionalized his textile using placeholders, for which he mixed tiny lime stone particles into the liquid polymer, which is later processed into the textile. The lime stone particles are then removed from the solid material with hydrochloric or acetic acid, so that tiny holes are formed at the sites of the nano particles. These are necessary for the material to function and to “breathe”. The outer walls of the cooling curtain are made of this porous material in order that the middle hydrophilic layer can deliver water to the surrounding area.

Stucki used a method developed in 2012 by ETH professor Wendelin Stark and his group to combine the different layers into one material. These layers are not glued together, as is customary in industrial processes; instead, they are placed on top of each other in a suitable solvent, whereby the outer layers dissolve slightly and connect to the middle layer. This is the only way that the researchers can ensure that the outer material of the membrane remains porous.

Amazingly thin: the membrane is hardly thicker than a sheet of paper.

Photograph: Peter Rüegg / ETH Zurich

A successful proof of concept

Stucki was able to prove the cooling curtain’s basic functionality by experiment. He put the triple-layer membrane in a water bath and measured the water loss into the surrounding area at 30°C and 50 percent humidity (between 1.2kg and 1.7kg water per day and square meter). The researchers calculated the results based on a cubic house with a 10m wall length. At an outside temperature of 40°C and an inside temperature of 30°C, the curtain surface of 80m2 was sufficient to dissipate more heat than supplied by the sunlight, meaning the house was passively cooled.

“We were able to show that our system fundamentally works,” says Stucki, “but to commercialize it, we still have a lot of questions to resolve.” For example, they need to determine how the material behaves microbiologically, since high temperatures and humidity form the ideal breeding ground for the growth of bacteria and fungi. Stucki says, however, that the synthetic material used for the outer layer could be replaced relatively easily with antiseptic materials; this is one of the advantages of functionalization using lime stone nano particles.

A further challenge is to ensure that the curtain is able to evaporate water over the entire surface, which will require improvements to the water transport in the membrane. It is also still unclear how long the membrane can function stably.

After completing his doctorate in the summer, Stuck will concentrate on commercializing fluorine-free outdoor textiles. He is currently looking for financing partners. However, he has not ruled out the possibility that the new membrane also has potential in the outdoor sector, as it is ideally suited to the regulation and removal of sweat – one of the most important properties of functional textiles.


Contacts and sources:
Samuel Schlaefli
ETH Zurich

Citation:  Stucki M, Stark W. Stabilization of 2D Water Films in Porous Triple-Layer Membranes with a Hydrophilic Core: Cooling Textiles and Passive Evaporative Room Climate Control. Advanced Engineering Materials, 2017. DOI: 10.1002/adem.201700134

Wednesday, July 26, 2017

Researchers Discover an Ugly Truth About Attractiveness

In today’s appearance-driven world, body image can be a powerful influence on our choices and behaviors, especially related to dieting. That image is sometimes shaped or distorted by many factors, including mass media images, parents, relationships, even our moods.

New research from Florida State University finds another factor — attractiveness of a romantic partner — can be a driving force behind the desire to diet and seek a slim body, though that motivation contrasts sharply between men and women.

Doctoral student Tania Reynolds and Assistant Professor of Psychology Andrea Meltzer found that women evaluated as less attractive were more motivated to diet and be thin if their husbands were attractive.

“The results reveal that having a physically attractive husband may have negative consequences for wives, especially if those wives are not particularly attractive,” Reynolds said.

Tania Reynolds is a doctoral candidate in FSU's Department of Psychology. "These findings are interesting, and we can use them in a productive way."

Credit: FSU

That extra motivation to diet, however, did not exist among women judged more attractive than their husbands. As for men, their motivation to diet was low regardless of their wives’ attractiveness or their own.

The study, published in the journal Body Image, offers productive insights about relationships in which a woman fears she’ll fall short of her partner’s expectations. Understanding the predictors that increase a woman’s risk of developing eating disorders and other health problems could lead to earlier assistance.

“The research suggests there might be social factors playing a role in women’s disordered eating,” Reynolds said. “It might be helpful to identify women at risk of developing more extreme weight-loss behaviors, which have been linked to other forms of psychological distress, such as depression, anxiety, substance abuse and dissatisfaction with life.”

Meltzer added: “In order to better understand women’s dieting motivations, the findings of this study highlight the value of adopting an approach that focuses on a couple’s relationship.”

The study advanced existing research from the Meltzer lab that found marriages tend to be more successful and satisfying when wives are more attractive than their husbands. It examined 113 newlywed couples — married less than four months, average age late 20s, living in the Dallas area — who agreed to be rated on their attractiveness.

Each participant completed a lengthy questionnaire focusing in part on their desire to diet or have a thin body. Some questions included, “I feel extremely guilty after eating,” “I like my stomach to be empty,” and “I’m terrified of gaining weight.”

A full-body photograph was taken of every participant and rated on a scale of 1 to 10. Two teams of undergraduate evaluators studied the photos: one at Southern Methodist University in Texas focused on spouses’ facial attractiveness, while another at FSU looked at body attractiveness. The evaluators varied in sex and ethnic makeup.

Reynolds said some research has shown women tend to overperceive just how thin their partners want them to be and, as a result, may inappropriately pursue dieting and a thin body.

“One way to help these women is for partners to be very reaffirming, reminding them, ‘You’re beautiful. I love you at any weight or body type,’” Reynolds said. “Or perhaps focusing on the ways they are a good romantic partner outside of attractiveness and emphasizing those strengths: ‘I really value you because you’re a kind, smart and supportive partner.’”

Reynolds thinks an interesting next step for research would be to explore whether women are more motivated to diet when they are surrounded by attractive female friends.

“If we understand how women’s relationships affect their decision to diet and the social predictors for developing unhealthy eating behaviors,” Reynolds said, “then we will be better able to help them.”


Contacts and sources:
Florida State University

Citation: Adopting a dyadic perspective to better understand the association between physical attractiveness and dieting motivations and behaviors Tania Reynolds. Andrea L. Meltzer Op
https://doi.org/10.1016/j.bodyim.2017.05.001

 

Closing Medical Marijuana Dispensaries Increases Crime, Says New Study

A new study published in the July issue of the Journal of Urban Economics finds that contrary to popular belief, medical marijuana dispensaries (MMDs) reduce crime in their immediate areas.

In the study, titled, “Going to pot? The impact of dispensary closures on crime,” researchers Tom Y. Chang from the USC Marshall School of Business, and Mireille Jacobson from The Paul Merage School of Business at UC Irvine, examined the short-term mass closing of hundreds of medical marijuana dispensaries in Los Angeles that took place in 2010.

“Contrary to popular wisdom, we found an immediate increase in crime around dispensaries ordered to close relative to those allowed to remain open,” said Jacobson.

Mireille Jacobson is an associate professor of Economics and Public Policy, and director of the Center for Health Care Management and Policy at the UCI Paul Merage School of Business.
Credit: UC Irvine

The two researchers found similar results when they examined restaurant closures.

“The connection between restaurants and MMDs is that they both contribute to the ‘walkability score’ of a given area. Areas with higher scores have more ‘eyes upon the street’ a factor that is proven to deter some types of crime,” said Jacobson.

The types of crime most impacted by MMD and restaurant closures were property crime and theft from vehicles. The researchers attributed this result to the fact that these types of crimes are most plausibly deterred by bystanders.

“Our results demonstrate that the dispensaries were not the crime magnets that they were often described as, but instead reduced crime in their immediate vicinity,” said Jacobson. 


Credit: Wikimedia Commons / Laurie Avocado

When Chang and Jacobson examined the impact of temporary restaurant closures in Los Angeles County, they found an increase in crime similar to what they found with MMDs. They also found that once a restaurant reopened, crime immediately disappeared.

Jacobson added, “We can conclude from our research that retail businesses are effective in lowering crime, even when the retail business is a medical marijuana dispensary.”



Contacts and sources:
The Paul Merage School of Business at UC Irvine

New Shark Species Glows in the Dark and Has a Huge Nose

Like finding a needle in a haystack, a team of scientists has discovered a new species of shark measuring less than a foot long and weighing under 2 pounds full-grown. This miniature, “glow-in-the-dark” shark is a member of the Lanternshark family (Squaliformes: Etmopteridae), which was serendipitously found 1,000 feet below the Pacific Ocean off the coast of the Northwestern Hawaiian Islands. It has taken more than 17 years to identify this new species (Etmopterus lailae ) since it was first discovered but was well worth the wait as this elusive creature is yet to be seen in the wild.


Etmopterus lailae has a strange head shape and an unusually large and bulgy snout where its nostrils and olfactory organs are located. These creatures are living in a deep sea environment with almost no light so they need to have a big sniffer to find food.
Credit: Florida Atlantic University

It often takes many years to identify a new species from the time it is discovered to the moment the news is shared with the scientific community. Results of the discovery of Etmopterus lailae were published in the journal Zootaxa. Stephen M. Kajiura, Ph.D., study co-author, a professor of biological sciences and director of the Elasmobranch Research Laboratory in the Charles E. Schmidt College of Science at Florida Atlantic University, is among the team of scientists who painstakingly worked on this project, which began while he was still in graduate school at the University of Hawaii.

“There are only about 450 known species of sharks worldwide and you don’t come across a new species all that often,” said Kajiura. “A large part of biodiversity is still unknown, so for us to stumble upon a tiny, new species of shark in a gigantic ocean is really thrilling. This species is very understudied because of its size and the fact that it lives in very deep water. They are not easily visible or accessible like so many other sharks.”

At first, Kajiura and his collaborators did not realize that they had discovered a new species until they submitted their research findings to a journal. The reviewer told them that the shark was not what they originally thought it was and that it might be a new species. Kajiura worked with David A. Ebert, Ph.D., study author, a taxonomist and program director of the Pacific Shark Research Center at Moss Landing Marine Laboratories in California, to identify this new species, now housed in the Bernice P. Bishop Museum in Hawaii.

Identifying the Etmopterus lailae required an extensive list of measurements, diligent categorization and thorough comparisons with other museum specimens.

“The unique features and characteristics of this new species really sets it apart from the other Lanternsharks,” said Kajiura. “For one thing, it has a strange head shape and an unusually large and bulgy snout where its nostrils and olfactory organs are located. These creatures are living in a deep sea environment with almost no light so they need to have a big sniffer to find food.”


Etmopterus lailae is a member of the Lanternshark family, which was serendipitously found 1,000 feet below the Pacific Ocean off the coast of the Northwestern Hawaiian Islands.

Credit: Florida Atlantic University


Some of the other distinctive characteristics of this new species are its flank markings that go forward and backward on their bellies, a naked patch without scales on the underside of its snout, as well as internal differences such as the number of vertebrae they have as well as fewer teeth than the other sharks. Like other Lanternsharks, the Etmopterus lailae is bioluminescent and the flanks on the bottom of its belly glow in the dark. These markings on its belly and tail also were specific to this new species.

There are a number of hypotheses for why Lanternsharks glow in the dark including mate recognition to ensure they are mating with the right species, serving as a form of camouflage to protect them from predators in the deep sea and using bioluminescence to act as a lure to attract little fish or shrimp.

"The research team's discovery of a new shark species is evidence of how much is still undiscovered in our world,” said Ata Sarajedini, Ph.D., dean of FAU’s Charles E. Schmidt College of Science. “This new species is the tip of the iceberg for what else might be out there and the great potential for all of the yet-to-be undescribed species that still need to be explored.”

The team of scientists also include Yannis P. Papastamatiou, Ph.D., Florida International University and Bradley M. Wetherbee, Ph.D., University of Rhode Island.

In 2000, Kajiura and Wetherbee discovered the Trigonognathus kabeyai or the Viper Dogfish in Hawaii, which also is part of the Lanternshark family. The Viper Dogfish’s distinctive feature is its snake-like mouth filled with crooked nail-like teeth that sets them apart from other Lanternsharks.





Contacts and sources:
Florida Atlantic University (FAU)

New Bio-Compatible Battery Makes Electricity Just Like the Body and All Living Things

Engineers at the University of Maryland have invented an entirely new kind of battery. It is bio-compatible because it produces the same kind of ion-based electrical energy used by humans and all living things.

In our bodies, flowing ions (sodium, potassium and other electrolytes) are the electrical signals that power the brain and control the rhythm of the heart, the movement of muscles, and much more.

In traditional batteries, the electrical energy, or current, flows in form of moving electrons. This current of electrons out of the battery is generated within the battery by moving positive ions from one end (electrode) of a battery to the other. The new UMD battery does the opposite. It moves electrons around in the device to deliver energy that is a flow of ions. This is the first time that an ionic current-generating battery has been invented.

“My intention is for ionic systems to interface with human systems,” said Liangbing Hu, the head of the group that developed that battery. Hu is a professor of materials science at the University of Maryland, College Park. He is also a member of the University of Maryland Energy Research Center and a principal investigator of the Nanostructures for Electrical Energy Storage Energy Frontier Research Center, sponsored by the Department of Energy, which funded the study.

“So I came up with the reverse design of a battery,” Hu said. “In a typical battery, electrons flow through wires to interface electronics, and ions flow through the battery separator. In our reverse design, a traditional battery is electronically shorted (that means electrons are flowing through the metal wires). Then ions have to flow through the outside ionic cables. In this case, the ions in the ionic cable – here, grass fibers -- can interface with living systems.”

The work of Hu and his colleagues was published in the July 24 issue of Nature Communications.

“Potential applications might include the development of the next generation of devices to micro-manipulate neuronal activities and interactions that can prevent and/or treat such medical problems as Alzheimer’s disease and depression,” said group member Jianhua Zhang, PhD, a staff scientist at the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), part of the National Institutes of Health in Bethesda, Md.

Credit:   University of Maryland

“The battery could be used to develop medical devices for the disabled, or for more efficient drug and gene delivery tools in both research and clinical settings, as a way to more precisely treat cancers and other medical diseases, said Zhang, who performed biological experiments to test that the new battery successfully transmitted current to livingcells.

“Looking far ahead on the scientific horizon, one hopes also that this invention may help to establish the possibility of direct machine and human communication,” he said.

Bio-compatible, bio-material batteries

Because living cells work on ionic current and existing batteries provide an electronic current, scientists have previously tried to figure out how to create biocompatibility between these two by patching an electronic current into an ionic current. The problem with this approach is that electronic current needs to reach a certain voltage to jump the gap between electronic systems and ionic systems. However, in living systems ionic currents flow at a very low voltage. Thus, with an electronic-to-ionic patch the induced current would be too high to run, say, a brain or a muscle. This problem could be eliminated by using ionic current batteries, which could be run at any voltage.

The new UMD battery also has another unusual feature – it uses grass to store its energy. To make the battery, the team soaked blades of Kentucky bluegrass in lithium salt solution. The channels that once moved nutrients up and down the grass blade were ideal conduits to hold the solution.

The demonstration battery the research team created looks like two glass tubes with a blade of grass inside, each connected by a thin metal wire at the top. The wire is where the electrons flow through to move from one end of the battery to the other as the stored energy slowly discharges. At the other end of each glass tube is a metal tip through which the ionic current flows.

The researchers proved that the ionic current is flowing by touching the ends of the battery to either end of a lithium-soaked cotton string, with a dot of blue-dyed copper ions in the middle. Caught up in the ionic current, the copper moved along the string toward the negatively charged pole, just as the researchers predicted.

Credit:   University of Maryland

“The microchannels in the grass can hold the salt solution, making them a stable ionic conductor,” said Chengwei Wang, first author of the paper and a graduate student in the Materials Science and Engineering department at the University of Maryland in College Park.

However, the team plans to diversify the types of ionic current electron batteries they can produce. “We are developing multiple ionic conductors with cellulose, hydrogels and polymers,” said Wang

This is not the first time UMD scientists have tested natural materials in new uses. Hu and his team previously have been studying cellulose and plant materials for electronic batteries, creating a battery and a supercapacitor out of wood and a battery from a leaf. They also have created transparent wood as a potentially more energy-efficient replacement for glass windows.

Creative Work

Ping Liu, an associate professor in nanoengineering at the University of California, San Diego, who was not involved with the study, said: “The work is very creative and its main value is in delivering ionic flow to bio systems without posing other dangers to them. Eventually, the impact of the work really resides in whether smaller and more biocompatible junction materials can be found that then interface with cells and organisms more directly and efficiently.”

The research was funded by Nanostructures for Electrical Energy Storage, a DOE Energy Frontier Research Center, and by Intramural Research Program of the NIDDK (DK043304).



Contacts and sources:

 University of Maryland 

Tuesday, July 25, 2017

Cosmologists Make New Maps of Dark Matter Dynamics

New maps of dark matter dynamics in the Universe have been produced by a team of international cosmologists.

Using advanced computer modelling techniques, the research team has translated the distribution of galaxies into detailed maps of matter streams and velocities for the first time.

The research was carried out by leading cosmologists from the UK, France and Germany.

Dr Florent Leclercq from the University of Portsmouth’s Institute of Cosmology and Gravitation said: “Dark matter is a substance of yet unknown nature that scientists believe makes up more than 80 per cent of the total mass of the Universe. As it does not emit or react to light, its distribution and evolution are not directly observable and have to be inferred.”

Slice through the celestial equator showing the radial component of the velocity field (in kilometres per second). Blue regions are falling towards us and red regions are flying away from us. Galaxies of the Sloan Digital Sky Survey main galaxy sample are overplotted. In the centre of the slice, the infalling dynamics of the Sloan Great Wall, one of the largest structure of the known Universe, can be observed


Credit: University of Portsmouth

The researchers used legacy survey data obtained during 2000 – 2008 from the Sloan Digital Sky Survey (SDSS), a major three-dimensional survey of the Universe. The survey has deep multi-colour images of one fifth of the sky and spectra for more than 900,000 galaxies.

The new dark matter maps cover the Northern Sky up to a distance of 600 megaparsecs, which is the equivalent of looking back about two billion years.

The researchers used a set of phase-space analysis tools and built on research from 2015, which reconstructed the initial conditions of the nearby Universe.

Detection probabilities for different structure types (from left to right: void, sheet, filament, and cluster), in the cosmic web as observed by the Sloan Digital Sky Survey. Structure types are classified using DIVA, an algorithm reflecting the dynamical trend, instead of the current density configuration. The red dot on the map shows our location.

Credit: University of Portsmouth

Dr Leclercq said: “Adopting a phase-space approach discloses a wealth of information, which was previously only analysed in simulations and thought to be inaccessible using observations.

“Accessing this information in galaxy surveys opens up new ways of assessing the validity of theoretical models in light of observations.”

The research is published in the Journal of Cosmology and Astroparticle Physics.


Contacts and sources:
Sophie Hall
University of Portsmouth

Bilingual Babies: Infants Need Just an Hour a Day to Learn Second Language



For years, scientists and parents alike have touted the benefits of introducing babies to two languages: Bilingual experience has been shown to improve cognitive abilities, especially problem-solving.

And for infants raised in households where two languages are spoken, that bilingual learning happens almost effortlessly. But how can babies in monolingual households develop such skills?

“As researchers studying early language development, we often hear from parents who are eager to provide their child with an opportunity to learn another language, but can’t afford a nanny from a foreign country and don’t speak a foreign language themselves,” said Naja Ferjan Ramirez, a research scientist at the University of Washington Institute of Learning & Brain Sciences (I-LABS).

UW student Jinnie Yi works with a toddler at one of the participating infant education centers in Madrid

UW student Jinnie Yi works with a toddler at one of the participating infant education centers in Madrid. A study by the UW Institute for Learning & Brain Sciences shows that infants and young children can develop bilingual skills through interactive learning.
Credit: I-LABS


A new study by I-LABS researchers, published July 17 in Mind, Brain, and Education, is among the first to investigate how babies can learn a second language outside of the home. The researchers sought to answer a fundamental question: Can babies be taught a second language if they don’t get foreign language exposure at home, and if so, what kind of foreign language exposure, and how much, is needed to spark that learning?



The researchers took their query all the way to Europe, developing a play-based, intensive, English-language method and curriculum and implementing it in four public infant-education centers in Madrid, Spain. Sixteen UW undergraduates and recent graduates served as tutors for the study, undergoing two weeks of training at I-LABS to learn the teaching method and curriculum before traveling to Spain. The country’s extensive public education system enabled the researchers to enroll 280 infants and children from families of varying income levels.

Based on years of I-LABS research on infant brain and language development, the method emphasizes social interaction, play, and high quality and quantity of language from the teachers. The approach uses “infant-directed speech” — often called “parentese” — the speech style parents use to talk to their babies, which has simpler grammar, higher and exaggerated pitch, and drawn-out vowels.

“Our research shows that parentese helps babies learn language,” Ferjan Ramirez said.

Babies aged 7 to 33.5 months were given one hour of English sessions a day for 18 weeks, while a control group received the Madrid schools’ standard bilingual program. Both groups of children were tested in Spanish and English at the start and end of the 18 weeks. The children also wore special vests outfitted with lightweight recorders that recorded their English learning. The recordings were analyzed to determine how many English words and phrases each child spoke.


An infant takes a look at a picture during a session with UW student Anna Kunz

Credit: I-LABS

The children who received the UW method showed rapid increases in English comprehension and production, and significantly outperformed the control group peers at all ages on all tests of English. By the end of the 18-week program, the children in the UW program produced an average of 74 English words or phrases per child, per hour; children in the control group produced 13 English words or phrases per child, per hour.

Ferjan Ramirez said the findings show that even babies from monolingual homes can develop bilingual abilities at this early age.

“With the right science-based approach that combines the features known to grow children’s language, it is possible to give very young children the opportunity to start learning a second language, with only one hour of play per day in an early education setting,” she said. “This has big implications for how we think about foreign-language learning.”

Follow-up testing 18 weeks later showed the children had retained what they learned. The English gains were similar between children attending the two schools serving predominantly low-income neighborhoods and the two serving mid-income areas, suggesting that wealth was not a significant factor in the infants’ ability to learn a foreign language. Children’s native language (Spanish) continued to grow as they were learning English, and was not negatively affected by introducing a second language.

“Science indicates that babies’ brains are the best learning machines ever created, and that infants’ learning is time-sensitive. Their brains will never be better at learning a second language than they are between 0 and 3 years of age,” said co-author Patricia Kuhl, co-director of I-LABS and a UW professor of speech and hearing sciences.

The results, Kuhl said, have the potential to transform how early language instruction is approached in the United States and worldwide:

“Parents in Madrid, in the United States and around the world are eager to provide their children with an opportunity to learn a foreign language early. The U.S. census shows that 27 percent of America’s children under the age of 6 are now learning a language other than English at home. While these children are fully capable of learning both their parents’ language and English, they often do not have adequate exposure to English prior to kindergarten entry and as a result, often lag behind their peers once they enter school,” she said.

“I-LABS’ new work shows we can create an early bilingual learning environment for dual-language learners in an educational setting, and in one hour per day, infants can ignite the learning of a second language earlier and much easier than we previously thought. This is doable for everybody,” Kuhl said.

 


Contacts and sources
Ferjan Ramirez / Deborah Bach
University of Washington

Dark Matter Is Cold and Not Fuzzy





Dark matter is the aptly named unseen material that makes up the bulk of matter in our universe. But what dark matter is made of is a matter of debate.

Scientists have never directly detected dark matter. But over decades, they have proposed a variety of theories about what type of material — from new particles to primordial black holes — could comprise dark matter and explain its many effects on normal matter. In a paper published July 20 in the journal Physical Review Letters, an international team of cosmologists uses data from the intergalactic medium — the vast, largely empty space between galaxies — to narrow down what dark matter could be.

The team’s findings cast doubt on a relatively new theory called “fuzzy dark matter,” and instead lend credence to a different model called “cold dark matter.” Their results could inform ongoing efforts to detect dark matter directly, especially if researchers have a clear idea of what sorts of properties they should be seeking.

“For decades, theoretical physicists have tried to understand the properties of the particles and forces that must make up dark matter,” said lead author Vid Iršič, a postdoctoral researcher in the Department of Astronomy at the University of Washington. “What we have done is place constraints on what dark matter could be — and ‘fuzzy dark matter,’ if it were to make up all of dark matter, is not consistent with our data.”

A depiction of hydrogen gas within the intergalactic medium, or IGM, with bright areas indicating high gas density.

Credit: Vid Iršič

Scientists had drawn up both the “fuzzy” and “cold” dark-matter theories to explain the effects that dark matter appears to have on galaxies and the intergalactic medium between them.

Cold dark matter is the older of these two theories, dating back to the 1980s, and is currently the standard model for dark matter. It posits that dark matter is made up of a relatively massive, slow-moving type of particle with “weakly interacting” properties. It helps explain the unique, large-scale structure of the universe, such as why galaxies tend to cluster in larger groups.

But the cold dark matter theory also has some drawbacks and inconsistencies. For example, it predicts that our own Milky Way Galaxy should have hundreds of satellite galaxies nearby. Instead, we have only a few dozen small, close neighbors.

The newer fuzzy dark matter theory addressed the deficiencies of the cold dark matter model. According to this theory, dark matter consists of an ultralight particle, rather than a heavy one, and also has a unique feature related to quantum mechanics. For many of the fundamental particles in our universe, their large-scale movements — traveling distances of meters, miles and beyond — can be explained using the principles of “classic” Newtonian physics. Explaining small-scale movements, such as at the subatomic level, requires the complex and often contradictory principles of quantum mechanics. But for the ultralight particle predicted in the fuzzy dark matter theory, movements at incredibly large scales — such as from one end of a galaxy to the other — also require quantum mechanics.

With these two theories of dark matter in mind, Iršič and his colleagues set out to model the hypothetical properties of dark matter based on relatively new observations of the intergalactic medium, or IGM. The IGM consists largely of dark matter — whatever that may be — along with hydrogen gas and a small amount of helium. The hydrogen within IGM absorbs light emitted from distant, bright objects, and astronomers have studied this absorption for decades using Earth-based instruments.

The team looked at how the IGM interacted with light emitted by quasars, which are distant, massive, starlike objects. One set of data came from a survey of 100 quasars by the European Southern Observatory in Chile. The team also included observations of 25 quasars by the Las Campanas Observatory in Chile and the W.M. Keck Observatory in Hawaii.


These images depict the absorption of light by hydrogen gas within the IGM, with bright areas indicating high gas density. The curves also show hydrogen absorption. On the left is a simulation based on the standard cold dark matter model. On the right is a simulation based on fuzzy dark matter. The left curve is more consistent with data analyzed by Iršič and colleagues

Credit: Vid Iršič

Using a supercomputer at the University of Cambridge, Iršič and co-authors simulated the IGM — and calculated what type of dark matter particle would be consistent with the quasar data. They discovered that a typical particle predicted by the fuzzy dark matter theory is simply too light to account for the hydrogen absorption patterns in the IGM. A heavier particle — similar to predictions of the traditional cold dark matter theory — is more consistent with their simulations.

“The mass of this particle has to be larger than what people had originally expected, based on the fuzzy dark matter solutions for issues surrounding our galaxy and others,” said Iršič.

An ultralight “fuzzy” particle could still exist. But it cannot explain why galactic clusters form, or other questions like the paucity of satellite galaxies around the Milky Way, said Iršič. A heavier “cold” particle remains consistent with the astronomical observations and simulations of the IGM, he added.

The team’s results do not address all of the longstanding drawbacks of the cold dark matter model. But Iršič believes that further mining of data from the IGM can help resolve the type — or types — of particles that make up dark matter. In addition, some scientists believe that there are no problems with the cold dark matter theory. Instead, scientists may simply not understand the complex forces at work in the IGM, Iršič added.

“Either way, the IGM remains a rich ground for understanding dark matter,” said Iršič.

Co-authors on the paper are Matteo Viel of the International School for Advanced Studies in Italy, the Astronomical Observatory of Trieste and the National Institute for Nuclear Physics in Italy; Martin Haehnelt of the University of Cambridge; James Bolton of the University of Nottingham; and George Becker of the University of California, Riverside. The work was funded by the National Science Foundation, the National Institute for Nuclear Physics in Italy, the European Research Council, the National Institute for Astrophysics in Italy, the Royal Society in the United Kingdom and the Kavli Foundation.



Contacts and sources:
James Urton
University of Washington


Citation: First Constraints on Fuzzy Dark Matter from Lyman-α Forest Data and Hydrodynamical Simulations. Vid Iršič, Matteo Viel, Martin G. Haehnelt, James S. Bolton, and George D. Becker
Phys. Rev. Lett. 119, 031302 – Published 20 July 2017

More and Bigger Long Period Comets Coming

Comets that take more than 200 years to make one revolution around the sun are notoriously difficult to study. Because they spend most of their time far from our area of the solar system, many "long-period comets" will never approach the sun in a person's lifetime. In fact, those that travel inward from the Oort Cloud--a group of icy bodies beginning roughly 300 billion kilometers away from the sun--can have periods of thousands or even millions of years.

NASA's Wide-field Infrared Survey Explorer (WISE) spacecraft has delivered new insights about these distant wanderers. A team of astronomers led by James Bauer, a research professor of astronomy at the University of Maryland, found that there are about seven times more long-period comets measuring at least 1 kilometer across than previously predicted.

A new study suggests that distant "long-period" comets -- which take more than 200 years to orbit the sun -- are more common than previously thought. This illustration shows how the researchers used data from NASA's Wide-field Infrared Survey Explorer (WISE) spacecraft to determine the nucleus sizes of several of these distant comets. They subtracted a model of how dust and gas behave in comets in order to obtain the core size.

Credit: NASA/JPL-Caltech



The researchers also found that long-period comets are, on average, nearly twice as large as "Jupiter family" comets, whose orbits are shaped by Jupiter's gravity and have periods of less than 20 years. The findings were published July 14, 2017, in The Astronomical Journal.

"The number of comets speaks to the amount of material left over from the solar system's formation," Bauer said. "We now know that there are more relatively large chunks of ancient material coming from the Oort Cloud than we thought."

The Oort Cloud is too distant to be seen by current telescopes, but is thought to be a spherical distribution of small icy bodies at the outermost edge of the solar system. The density of comets within it is low, so the odds of comets colliding within it are low. Long-period comets that WISE observed probably got kicked out of the Oort Cloud millions of years ago. The observations were carried out in 2010 during the spacecraft's primary mission, before it was renamed NEOWISE and reactivated to target near-Earth objects (NEOs) in 2013.

"Our study is a rare look at objects perturbed out of the Oort Cloud," said Amy Mainzer, a co-author of the study based at NASA's Jet Propulsion Laboratory in Pasadena, California and principal investigator of the NEOWISE mission. "They are the most pristine examples of what the solar system was like when it formed."

Astronomers already had broader estimates of how many long-period and Jupiter family comets are in our solar system, but had no good way of measuring the sizes of long-period comets. This is because the cloud of gas and dust that surrounds each comet--known as a coma--appears hazy in images and obscures the comet's nucleus.

By using WISE data that shows the infrared glow of the coma, the scientists were able to "subtract" the coma from each comet and estimate the size of the nucleus. The data came from WISE observations of 164 cometary bodies--including 95 Jupiter family comets and 56 long-period comets.

The results reinforce the idea that comets that pass by the sun more frequently tend to be smaller than those spending much more time away from the sun. That is because Jupiter family comets get more heat exposure, which causes volatile substances like water to sublimate and drag away other material from the comet's surface as well.

"Our results mean there's an evolutionary difference between Jupiter family and long-period comets," Bauer said.

The existence of so many more long-period comets than predicted suggests that more of them have likely impacted planets, delivering icy materials from the outer reaches of the solar system.

Researchers also found clustered orbits among the long-period comets they studied, suggesting there could have been larger bodies that broke apart to form these groups.

The results will be important for assessing the likelihood of comets impacting our solar system's planets, including Earth.

"Comets travel much faster than asteroids, and some of them are very big," Mainzer said. "Studies like this will help us define what kind of hazard long-period comets may pose."

NASA's Jet Propulsion Laboratory in Pasadena, California, managed and operated WISE for NASA's Science Mission Directorate in Washington, D.C. The NEOWISE project is funded by the Near-Earth Object Observation Program, now part of NASA's Planetary Defense Coordination Office. The spacecraft was put into hibernation mode in 2011 after twice scanning the entire sky, thereby completing its main objectives. In September 2013, WISE was reactivated, renamed NEOWISE and assigned a new mission to assist NASA's efforts to identify potentially hazardous near-Earth objects.



Contacts and sources:
Matthew Wright
University of Maryland