пятница, 8 февраля 2019 г.

Better Betas Stem-cell therapy offers great hope for diseases…

Better Betas

Stem-cell therapy offers great hope for diseases in which certain types of cells are dysfunctional or dying – such as diabetes, which affects insulin-producing beta cells of the pancreas. The idea is that the desired replacement cells can be grown from human stem cells (capable of developing into almost any cell type) and then engrafted into the patient. Over the years, scientists have been working to create effective stem-cell derived beta cells, but often these cells’ insulin production has been erratic. Now, through painstaking tweaking of the culturing conditions, researchers have come up with their best beta cell recipe yet. Indeed, the new improved cells (pictured) are superior at responding to glucose and appropriately secreting insulin (stained bright poppy red) than previous versions. And, when transferred into mice, these cells could effectively control the animals’ blood sugar for months. As such, the cells may be nearing readiness for clinical trial.

Written by Ruth Williams

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Gaia clocks new speeds for Milky Way-Andromeda collision

ESA – Gaia Mission patch.

8 February 2019

ESA’s Gaia satellite has looked beyond our Galaxy and explored two nearby galaxies to reveal the stellar motions within them and how they will one day interact and collide with the Milky Way – with surprising results.

Future galaxy trajectories

Our Milky Way belongs to a large gathering of galaxies known as the Local Group and, along with the Andromeda and Triangulum galaxies – also referred to as M31 and M33, respectively – makes up the majority of the group’s mass.

Astronomers have long suspected that Andromeda will one day collide with the Milky Way, completely reshaping our cosmic neighbourhood. However, the three-dimensional movements of the Local Group galaxies remained unclear, painting an uncertain picture of the Milky Way’s future.

“We needed to explore the galaxies’ motions in 3D to uncover how they have grown and evolved, and what creates and influences their features and behaviour,” says lead author Roeland van der Marel of the Space Telescope Science Institute in Baltimore, USA.

“We were able to do this using the second package of high-quality data released by Gaia.”

Gaia is currently building the most precise 3D map of the stars in the nearby Universe, and is releasing its data in stages. The data from the second release, made in April 2018, was used in this research.

Gaia second data release

Previous studies of the Local Group have combined observations from telescopes including the NASA/ESA Hubble Space Telescope and the ground-based Very Long Baseline Array to figure out how the orbits of Andromeda and Triangulum have changed over time. The two disc-shaped spiral galaxies are located between 2.5 and 3 million light-years from us, and are close enough to one another that they may be interacting.

Two possibilities emerged: either Triangulum is on an incredibly long six-billion-year orbit around Andromeda but has already fallen into it in the past, or it is currently on its very first infall. Each scenario reflects a different orbital path, and thus a different formation history and future for each galaxy.

While Hubble has obtained the sharpest view ever of both Andromeda and Triangulum, Gaia measures the individual position and motion of many of their stars with unprecedented accuracy.

“We combed through the Gaia data to identify thousands of individual stars in both galaxies, and studied how these stars moved within their galactic homes,” adds co-author Mark Fardal, also of Space Telescope Science Institute.

Hubble view of Triangulum

“While Gaia primarily aims to study the Milky Way, it’s powerful enough to spot especially massive and bright stars within nearby star-forming regions – even in galaxies beyond our own.”

The stellar motions measured by Gaia not only reveal how each of the galaxies moves through space, but also how each rotates around its own spin axis.

A century ago, when astronomers were first trying to understand the nature of galaxies, these spin measurements were much sought-after, but could not be successfully completed with the telescopes available at the time.

“It took an observatory as advanced as Gaia to finally do so,” says Roeland.


“For the first time, we’ve measured how M31 and M33 rotate on the sky. Astronomers used to see galaxies as clustered worlds that couldn’t possibly be separate ‘islands’, but we now know otherwise.

“It has taken 100 years and Gaia to finally measure the true, tiny, rotation rate of our nearest large galactic neighbour, M31. This will help us to understand more about the nature of galaxies.”

By combining existing observations with the new data release from Gaia, the researchers determined how Andromeda and Triangulum are each moving across the sky, and calculated the orbital path for each galaxy both backwards and forwards in time for billions of years.

Stellar motions in Andromeda

“The velocities we found show that M33 cannot be on a long orbit around M31,” says co-author Ekta Patel of the University of Arizona, USA. “Our models unanimously imply that M33 must be on its first infall into M31.”

While the Milky Way and Andromeda are still destined to collide and merge, both the timing and destructiveness of the interaction are also likely to be different than expected.

As Andromeda’s motion differs somewhat from previous estimates, the galaxy is likely to deliver more of a glancing blow to the Milky Way than a head-on collision. This will take place not in 3.9 billion years’ time, but in 4.5 billion – some 600 million years later than anticipated.

“This finding is crucial to our understanding of how galaxies evolve and interact,” says Timo Prusti, ESA Gaia Project Scientist.

Hubble view of Andromeda

“We see unusual features in both M31 and M33, such as warped streams and tails of gas and stars. If the galaxies haven’t come together before, these can’t have been created by the forces felt during a merger. Perhaps they formed via interactions with other galaxies, or by gas dynamics within the galaxies themselves.

“Gaia was designed primarily for mapping stars within the Milky Way — but this new study shows that the satellite is exceeding expectations, and can provide unique insights into the structure and dynamics of galaxies beyond the realm of our own. The longer Gaia watches the tiny movements of these galaxies across the sky, the more precise our measurements will become.”

Notes for editors:

“First Gaia Dynamics of the Andromeda System: DR2 Proper Motions, Orbits, and Rotation of M31 and M33” by R. P. van der Marel et al. is published in Astrophysical Journal.

ESA’s Gaia satellite was launched in 2013 to create the most precise three-dimensional map of one billion of the stars within the Milky Way. The mission has released two lots of data so far: Gaia Data Release 1 on 14 September 2016, and Gaia Data Release 2 on 25 April 2018 (the latter of which was used in this study). More releases will follow in coming years.

Related links:

Astrophysical Journal: https://iopscience.iop.org/article/10.3847/1538-4357/ab001b

Gaia Data Release 1: http://www.esa.int/Our_Activities/Space_Science/Gaia/Gaia_s_billion-star_map_hints_at_treasures_to_come

Gaia Data Release 2: https://www.esa.int/Our_Activities/Space_Science/Gaia/Gaia_creates_richest_star_map_of_our_Galaxy_and_beyond

ESA’s Gaia: http://www.esa.int/Our_Activities/Space_Science/Gaia

Text, Credits: ESA/Markus Bauer/Timo Prusti/Steward Observatory/University of Arizona/Ekta Patel/Space Telescope Science Institute/Mark Fardal/Roeland P. van der Marel/Images Credits: Orbits: E. Patel, G. Besla (University of Arizona), R. van der Marel (STScI); Images: Orbits: E. Patel, G. Besla (University of Arizona), R. van der Marel (STScI); Images: ESA (Milky Way); ESA/Gaia/DPAC (M31, M33)/Gaia/DPAC, CC BY-SA 3.0 IGO/NASA, ESA, and M. Durbin, J. Dalcanton, and B. F. Williams (University of Washington); CC BY 4.0/ESA/Gaia (star motions); NASA/Galex (background image); R. van der Marel, M. Fardal, J. Sahlmann (STScI)/NASA, ESA, J. Dalcanton (University of Washington, USA), B. F. Williams (University of Washington, USA), L. C. Johnson (University of Washington, USA), the PHAT team, and R. Gendler./Animation Credit: ESA.

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Direct killing by humans pushing Earth’s biggest fauna toward extinction

At least 200 species of large animals are decreasing in number and more than 150 are under threat of extinction, according to new research that suggests humans’ meat consumption habits are primarily to blame.

Direct killing by humans pushing Earth’s biggest fauna toward extinction
Leatherback sea turtle [Credit: Oregon State University]

Findings published in Conservation Letters involved a study of nearly 300 species of “megafauna.” Of those species’ populations, 70 percent are in decline, and 59 percent of the species are threatened with disappearing from the globe, said the study’s corresponding author, William Ripple, distinguished professor of ecology in the Oregon State University College of Forestry.
“Direct harvest for human consumption of meat or body parts is the biggest danger to nearly all of the large species with threat data available,” Ripple said. “Thus, minimizing the direct killing of these vertebrate animals is an important conservation tactic that might save many of these iconic species as well as all of the contributions they make to their ecosystems.”

Ripple and colleagues in the College of Forestry were part of an international collaboration that built a list of megafauna based on body size and taxonomy — qualifying for the list were species unusually large in comparison to other species in the same class.

Direct killing by humans pushing Earth’s biggest fauna toward extinction
Whale shark [Credit: Oregon State University]

The mass thresholds the researchers decided on were 100 kilograms (220 pounds) for mammals, ray-finned fish and cartilaginous fish and 40 kilograms (88 pounds) for amphibians, birds and reptiles since species within these classes are generally smaller.
“Those new thresholds extended the number and diversity of species included as megafauna, allowing for a broader analysis of the status and ecological effects of the world’s largest vertebrate animals,” Ripple said. “Megafauna species are more threatened and have a higher percentage of decreasing populations than all the rest of the vertebrate species together.”

Over the past 500 years, as humans’ ability to kill wildlife at a safe distance has become highly refined, 2 percent of megafauna species have gone extinct. For all sizes of vertebrates, the figure is 0.8 percent.

Direct killing by humans pushing Earth’s biggest fauna toward extinction
African elephants [Credit: Oregon State University]

“Our results suggest we’re in the process of eating megafauna to extinction,” Ripple said. “Through the consumption of various body parts, users of Asian traditional medicine also exert heavy tolls on the largest species. In the future, 70 percent will experience further population declines and 60 percent of the species could become extinct or very rare.”
Nine megafauna species have either gone extinct overall, or gone extinct in all wild habitats, in the past 250 years, including two species of giant tortoise, one of which disappeared in 2012, and two species of deer.

“In addition to intentional harvesting, a lot of land animals get accidentally caught in snares and traps, and the same is true of gillnets, trawls and longlines in aquatic systems,” Ripple said. “And there’s also habitat degradation to contend with. When taken together, these threats can have major negative cumulative effects on vertebrate species.”

Direct killing by humans pushing Earth’s biggest fauna toward extinction
Chinese giant salamander [Credit: Oregon State University]

Among those threatened is the Chinese giant salamander, which can grow up to 6 feet long and is one of only three living species in an amphibian family that traces back 170 million years. Considered a delicacy in Asia, it’s under siege by hunting, development and pollution, and its extinction in the wild is now imminent.
“Preserving the remaining megafauna is going to be difficult and complicated,” Ripple said. “There will be economic arguments against it, as well as cultural and social obstacles. But if we don’t consider, critique and adjust our behaviors, our heightened abilities as hunters may lead us to consume much of the last of the Earth’s megafauna.”

Collaborators included Christopher Wolf, Thomas Newsome and Matthew Betts of the College of Forestry, as well as researchers at the University of California Los Angeles and in Australia, Canada, Mexico and France.

Author: Steve Lundeberg | Source: Oregon State University. [February 06, 2019]



Fireball over Colorado

60 reports from 4 states

The AMS has received 60 reports so far about of a bright fireball seen above Montrose, CO on Thursday January 7th, 2019 around 6:13pm MST (Jan 8, 2019 – 01:13 Universal Time). The event was mainly seen from Colorado but we also received reports from Utah, New Mexico and Wyoming.

If you witnessed this event and/or if you have a video or a photo of this event, please

Submit an Official Fireball Report

If you want to learn more about Fireballs: read our Fireball FAQ.

AMS Event #643-2019 – Witness location and estimated ground trajectory


The preliminary 3D trajectory computed based on all the reports submitted to the AMS shows that the fireball was traveling from East to West and ended its flight South-West of Montrose, CO.

AMS Event #643-2019 – Estimated 3D trajectory

Videos and Images

We didn’t receive any video of the event yet but several people shared videos of the event on Facebook and Twitter:

We also received multiple images of what looks like a smoke trail. Fireballs can develop two types of trails behind them: trains and smoke trails. A train is a glowing trail of ionized and excited air molecules left behind after the passage of the meteor. Most trains last only a few seconds, but on rare occasions a train may last up to several minutes. The second type of trail is called a smoke trail, and is more often seen in daylight fireballs than at night. Generally occurring below 80 km of altitude, smoke trails are a non-luminous trail of particulate stripped away during the ablation process.

AMS Event #643-2019 – Smoke Trail photo shared by eye witness K. Ulmer


Based on our first analysis, it looks like the event was a fireball. A fireball is another term for a very bright meteor, generally brighter than magnitude -4, which is about the same magnitude of the planet Venus currently visible in the morning sky.

Several thousand meteors of fireball magnitude occur in the Earth’s atmosphere each day. The vast majority of these, however, occur over the oceans and uninhabited regions, and a good many are masked by daylight. Those that occur at night also stand little chance of being detected due to the relatively low numbers of persons out to notice them.

Additionally, the brighter the fireball, the more rare is the event. As a general thumb rule, there are only about 1/3 as many fireballs present for each successively brighter magnitude class, following an exponential decrease. Experienced observers can expect to see only about 1 fireball of magnitude -6 or better for every 200 hours of meteor observing, while a fireball of magnitude -4 can be expected about once every 20 hours or so.


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2019 February 8 Moon, Four Planets, and Emu Image Credit &…

2019 February 8

Moon, Four Planets, and Emu
Image Credit & Copyright: Alex Cherney (Terrastro, TWAN)

Explanation: A luminous Milky Way falls toward the horizon in this deep skyscape, starting at the top of the frame from the stars of the Southern Cross and the dark Coalsack Nebula. Captured in the dark predawn of February 2nd from Central Victoria, Australia, planet Earth, the 26 day old waning crescent Moon still shines brightly near the horizon. The second and third brightest celestial beacons are Venus and Jupiter along the lower part of the Milky Way’s central bulge. Almost in line with the brighter planets and Moon, Saturn is the pinprick of light just visible below and right of the lunar glow. Australia’s first astronomers saw the elongated, bulging shape of the familiar Milky Way as a great celestial Emu. The Moon and planets could almost be the Emu’s eggs on this starry night.

∞ Source: apod.nasa.gov/apod/ap190208.html

Species ‘hotspots’ created by immigrant influx or evolutionary speed...

Some corners of the world teem with an extraordinary variety of life. Charles Darwin noted that: “The same spot will support more life if occupied by very diverse forms.”

Species 'hotspots' created by immigrant influx or evolutionary speed depending on climate
These specimens, from Cambridge University’s Museum of Zoology, were collected and labelled on the second voyage
of the HMS Beagle (1831-1836) that carried Darwin to the Galapagos Islands. Researchers say these famously
diverse finches are an iconic example of rapid speciation in a tropical hotspot
[Credit: University of Cambridge/Chris Green]

The question of how these ‘hotspots’ of biodiversity – from California to the Galapagos – acquired such a wealth of species has long puzzled naturalists.

Now, scientists at the University of Cambridge have conducted a ‘big data’ study of almost all the world’s mammal and bird species to reveal the answer – and it’s very different depending on climate.

According to the study, tropical hotspots close to the equator have generated new species at a much faster rate than their surrounding areas during the last 25 million years of evolution.

However, biodiversity hotspots in more temperate northerly regions, such as the Mediterranean basin and Caucasus Mountains, are mainly populated with immigrant species that originated elsewhere.

Scientists say these migrants may well have been escaping the effects of long-term “geological processes” such as vast encroaching glaciers. Warmer climes, as well as peninsulas and mountain ranges, could have offered shelter.

The researchers argue that their new study, published in the journal Science Advances, shows how these “contrasting macroevolutionary routes” have shaped the uneven distribution of species across the planet.

“We’ve known for decades that just a subset of places on Earth, no more than 20%, contain about half of all vertebrate species. However, we lacked the tools and data to understand why these patterns exist,” said senior author Dr Andrew Tanentzap, from Cambridge’s Department of Plant Sciences.

“Large-scale initiatives to map species across the planet and in the Tree of Life, as well as advances in computing, are expanding our understanding of evolution in exciting ways. This study can now provide an answer to the old question of why diversity varies so much across the world.”

Cambridge scientists used new computational techniques to combine several giant datasets. These included the global distribution of 11,093 bird species and 5,302 mammals, and detailed evolutionary trees that track the origin of thousands of organisms through deep time.

In this way, the researchers were able to analyse the development of particularly species-rich areas within each of the Earth’s great “biogeographical regions” – from Australasia to the Nearctic.

They found that biodiversity hotspots in the tropics, such as South American forests and Indonesian islands, had higher rates of “speciation” – the formation of new and distinct species – over the last 25 million years.

For example, speciation rates for birds in hotspots of the Indo-Malay region were, on average, 36% higher than that region’s non-hotspot areas. Hotspots in the Neotropics had almost 28% greater bird speciation compared to non-hotspots.

“Species generation is faster in the tropics, but we can now see it is extra-quick in these hotspots of biodiversity,” said study lead author Dr Javier Igea, also from Cambridge’s Department of Plant Sciences.

“More rainfall and hotter temperatures bolster the ecosystems of tropical hotspots, producing more plants, more animals that feed on those plants, and so on,” he said.

“The greater available energy and range of habitats within these hotspots supported the acceleration of species diversification.”

The tropical hotspot of Madagascar, for example, holds 12 species of true lemur that diversified in the last ten million years. All of the 17 species of earthworm mice endemic to the Philippines were generated in the last six million years.

The famously diverse finches Darwin found in the Galapagos Islands, as featured in his revolutionary book On the Origin of Species, are an iconic example of rapid speciation in a tropical hotspot.

However, when it came to the more temperate regions of the Nearctic (North America) and Palearctic (Eurasia and North Africa), the researchers discovered a different story.

While the hotspots of these regions also had a wider range of resource and habitat than neighbouring areas, the data from the evolutionary – or phylogenetic – trees revealed that most of their animals “speciated” somewhere else.

“Biodiversity hotspots in temperate zones have been shaped mainly by migration that occurred during the last 25 million years,” said Igea.

“We suspect that this influx of immigrant species resulted from climate fluctuations across millions of years, particularly cooling. Biodiversity hotspots may have acted as a refuge where more species could survive in harsh climatic conditions,” he said.

Igea points to species such as the Iberian lynx, now a native of the Mediterranean Basin hotspot, but found in central Europe during the Pleistocene – prior to the last Ice Age.

Or the yellow-billed magpie, which became isolated in California after becoming separated from its ancestral species – most likely due to glaciations – over three million years ago.

“We found that hotspots across the world all have a greater complexity of habitats and more environmental energy, but the processes that drive the biodiversity are very different for tropical and temperate zones,” Igea said.

For Tanentzap, the importance of species migration in temperate regions suggests that maintaining connectivity between hotspots should be a priority for future conservation efforts.

“Many of these hotspot regions have species found nowhere else on Earth, yet face devastating levels of habitat loss. Protecting these areas is vital to conserving the natural world’s diversity,” he said.

Source: University of Cambridge [February 06, 2019]



Cerussite | #Geology #GeologyPage #Mineral Locality: Ojuela…

Cerussite | #Geology #GeologyPage #Mineral

Locality: Ojuela Mine, Mapimí, Mun. de Mapimí, Durango, Mexico

Crystal size:Up to 9 mm wide

Overall size: 52mm x 26 mm x 25 mm

Photo Copyright © Minservice

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Research explains how snakes lost their limbs

Snakes and lizards are reptiles that belong to the order Squamata. They share several traits but differ in one obvious respect: snakes do not have limbs. The two suborders diverged more than 100 million years ago.

Research explains how snakes lost their limbs
The study is part of an effort to understand how changes in the genome lead to changes in phenotypes
[Credit: Jax Strong/WikiCommons]

Identification of the genetic factors involved in this loss of limbs is a focus of the article “Phenotype loss is associated with widespread divergence of the gene regulatory landscape in evolution” published by Juliana Gusson Roscito and collaborators in Nature Communications.

Another equally interesting focus of the article is eye degeneration in certain subterranean mammals.

“We investigated these two cases in order to understand a much more general process, which is how genome changes during evolution lead to phenotype changes,” Roscito told.

Currently working as a researcher at the Max Planck Institute for Molecular Cell Biology and Genetics in Dresden, Germany, Roscito has been a postdoctoral fellow in Brazil and a research intern abroad with São Paulo Research Foundation — FAPESP’s support. Her postdoctoral scholarship was linked to the Thematic Project Comparative phylogeography, phylogeny, paleoclimate modeling and taxonomy of neotropical reptiles and amphibians, for which Miguel Trefaut Urbano Rodrigues is the principal investigator under the aegis of the FAPESP Research Program on Biodiversity Characterization, Conservation, Restoration and Sustainable Use (BIOTA-FAPESP).

Rodrigues is a Full Professor at the University of São Paulo’s Bioscience Institute (IB-USP) in Brazil and supervised Roscito’s postdoctoral research. He is also a coauthor of the recently published article.

“The research consisted of an investigation of the genomes of several species of vertebrates, including the identification of genomic regions that changed only in snakes or subterranean mammals, while remaining unchanged in other species that have not lost their limbs or have normal eyes,” Roscito said.

“In mammals with degenerated visual systems, we know several genes have been lost, such as those associated with the eye’s crystalline lens and with the retina’s photoreceptor cells. These genes underwent mutations during the evolutionary process. Eventually, they completely lost their functionality, meaning the capacity to encode proteins. But that’s not what happened to snakes, which haven’t lost the genes associated with limb formation. To be more precise, the study that sequenced the genome of a snake did detect the loss of one gene, but only one. Therefore, the approach we chose in our research consisted of investigating not the genes but the elements that regulate gene expression.”

Gene expression depends on regulatory elements for the information the gene contains to be transcribed into RNA (ribonucleic acid) and later translated into protein. This process is regulated by cis-regulatory elements (CREs), which are sequences of nucleotides in DNA (deoxyribonucleic acid) located near the genes they regulate. CREs control the spatiotemporal and quantitative patterns of gene expression.

“A regulatory element can activate or inhibit the expression of a gene in a certain part of the organism, such as the limbs, for example, while a different regulatory element can activate or inhibit the expression of the same gene in a different part, such as the head. If the gene is lost, it ceases to be expressed in both places and can often have a negative effect on the organism’s formation.

However, if only one of the regulatory elements is lost, expression may disappear in one part while being conserved in the other,” Roscito explained.

Tegu lizard

From a computational standpoint, CREs are not as easy to identify as genes. Genes have a characteristic syntax, with base pairs that show where the genes begin and end. This is not the case for CREs, so they have to be identified indirectly. This identification is normally based on the conservation of DNA sequences among many different species.

“To detect the divergence of specific sequences in snakes, it’s necessary to compare the genomes of snakes with the genomes of various reptiles and other vertebrates that have fully developed limbs. Genome sequences for reptiles with well-developed limbs are scarce, so we sequenced and assembled the genome of the fully limbed tegu lizard, Salvator merianae. This is the first species of the teiid lineage ever sequenced,” the authors said.

“Using the tegu genome as a reference, we created an alignment of the genomes of several species, including two snakes (boa and python), three other limbed reptiles (green anole lizard, dragon lizard and gecko), three birds, an alligator, three turtles, 14 mammals, a frog, and a coelacanth. This alignment of 29 genomes was used as the basis for all further analyses.”

The researchers identified more than 5,000 DNA regions that are considered candidate regulatory elements in several species. They then searched the large database using ingenious technical procedures that are described in detail in the article and obtained a set of CREs the mutation of which may have led to the disappearance of limbs in the ancestors of snakes.

“There are several studies concerning a well-known regulatory element that regulates a gene that, when modified, causes various defects in limbs. Snakes have mutations in this CRE. In a study published in 2016, the mouse CRE was replaced with the snake version, resulting in practically limbless descendants. This was a functional demonstration of a mechanism that may have led to limb loss in snakes. However, this CRE is only one of the regulatory elements for one of several genes that control limb formation,” Roscito said.

“Our study extended the set of CREs. We showed that several other regulatory elements responsible for regulating many genes have mutated in snakes. The signature is far more comprehensive. An entire signaling cascade is affected.”

Source: Fundação de Amparo à Pesquisa do Estado de São Paulo [February 06, 2019]



Bubble Blowing Black Hole Jet’s Impact on Galactic Evolution

Figure 1. The contours in this image show the flux of the molecular (blue) and ionized (green) emission detected by Gemini/NIFS overlaid on the Hubble Space Telescope image. While the ionized emission is centrally concentrated, the molecular emission extends further to the north and south of the nucleus, suggesting it is part of the massive circumnuclear disk.

Figure 2. The paler green region represents low surface-brightness jet plasma filling the jet-driven bubble, which drives a shock into the surrounding gas and causes ionized emission (dark red). Jet plasma also percolates radially through channels in the clumpy circumnuclear disk (blue), driving shocks into neutral gas and causing molecular emission. The pale blue circles represent clouds of neutral gas. The line of sight is indicated by the dashed line; the disk is inclined such that the Western lobe is partially obscured by the disk, whereas the Eastern lobe is completely obscured by the disk.

Astronomers using adaptive optics on the 8-meter Gemini North telescope have resolved, for the first time in near-infrared light, a giant elliptical galaxy with a young radio jet down to unprecedented scales. The observations also show how the jets, emanating from a black hole at the center of this galaxy, are heating the interstellar medium, which may have a significant impact on the evolution of the host galaxy.

Using adaptive optics (AO) and near-infrared imaging on the 8-meter Gemini North telescope in Hawai‘i, a team of astronomers lead by PhD student Henry Zovaro (The Australian National University) report the discovery of shocked molecular and ionized gas resulting from a jet-driven feedback coming from the center of a compact radio galaxy. The discovery offers important information on how such activity can influence the evolution of its host galaxy.

The galaxy, which goes by the name MCG 5-4-18, is a nearby giant elliptical galaxy harboring a young compact radio source, known as 4C 31.04, powered by a supermassive black hole with powerful jets. The radio source has two edge-brightened lobes (separated by about 320 thousand light years) that may only be a few thousand years old. The researchers demonstrate that 4C 31.04 is currently in a early phase of jet evolution, called the “energy-driven bubble” stage, where the jets inflate a bubble that expands out of the plane of the disk and interacts strongly with the galaxy’s interstellar medium.

The relative closeness of 4C 31.04 (about 270 megaparsecs, or 900 million light years) enabled the team to probe the interactions between the radio jet and the surrounding interstellar medium using H- and K-band infrared observations obtained with Gemini’s Near-infrared Integral Field Spectrometer (NIFS). “This is the first time that observations in optical or near-infrared have resolved the host galaxy down to scales comparable to the size of the radio lobes,” Zovaro says.

The shocked gases discovered by the team are important because they serve as tracers of the energetic interactions between the jet and the surrounding material. The study uncovered two different phases of heated gas in the circumnuclear disk: 1) the innermost parts of the disk form a jet-blown bubble of ionized gas 1,300 light years in diameter; and 2) the outer region is comprised of very warm molecular gas, around 1,000 Kelvin, reaching distances greater than 3,000 light years (Figure 1).

Zovaro explains how the two phases are related (Figure 2): “The bubble pushes a forward shock into the interstellar medium, giving rise to the ionized gas. Jet plasma also percolates into the circumnuclear disk, shocking and radially accelerating gas clouds, warming the interstellar medium and giving rise to the molecular emission.” Zovaro suggests that the warm molecular gas is part of the extended structure of the massive circumnuclear disk. Because the molecular gas cools rapidly, he says, this phase is very short-lived, and only represents a very small fraction of the total warm mass.

“All of the images of the radio emission that are currently available only show the jets reaching distances of about 100 parsec from the nucleus, whereas our NIFS data show that, in fact, the jet’s plasma reaches all the way out to approximately one kiloparsec in the disk,” Zovaro says, noting that deeper radio observations would be required to detect the jets at such radii. “This is an important finding,” he adds, “because it shows that we can’t simply ignore the effects of radio jets upon the evolution of their host galaxy, even if the radio source appears to be very small.”

The Gemini observations are featured in the accepted paper in the Monthly Notices of the Royal Astronomical Society.

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ESA’s Mars rover has a name – Rosalind Franklin

ESA – ExoMars Mission logo.

7 February 2019

The ExoMars rover that will search for the building blocks of life on the Red Planet has a name: Rosalind Franklin. The prominent scientist behind the discovery of the structure of DNA will have her symbolic footprint on Mars in 2021. 

A panel of experts chose ‘Rosalind Franklin’ from over 36 000 entries submitted by citizens from all ESA Member States, following a competition launched by the UK Space Agency in July last year.

ExoMars rover

The ExoMars rover will be the first of its kind to combine the capability to roam around Mars and to study it at depth. The Red Planet has hosted water in the past, but has a dry surface exposed to harsh radiation today.

The rover bearing Rosalind Franklin’s name will drill down to two metres into the surface to sample the soil, analyse its composition and search for evidence of past – and perhaps even present – life buried underground.

The rover is part of the ExoMars programme, a joint endeavour between ESA and the Russian State Space Corporation, Roscosmos.

What’s in a name?

Rosalind Elsie Franklin was a British chemist and X-ray crystallographer who contributed to unravelling the double helix structure of our DNA. She also made enduring contributions to the study of coal, carbon and graphite. ESA has a long tradition of naming its missions for great scientists, including Newton, Planck and Euclid.

Rosalind Franklin

“This name reminds us that it is in the human genes to explore. Science is in our DNA, and in everything we do at ESA. Rosalind the rover captures this spirit and carries us all to the forefront of space exploration,” says ESA Director General Jan Woerner.

The name was revealed this morning in the ‘Mars Yard’ at Airbus Defence and Space in Stevenage, in the United Kingdom, where the rover is being built. ESA astronaut Tim Peake met the competition entrants who chose the winning name, and toured the facility with UK Science Minister Chris Skidmore.

“This rover will scout the martian surface equipped with next-generation instruments – a fully-fledged automated laboratory on Mars,” says Tim.

ExoMars rover name announced

“With it, we are building on our European heritage in robotic exploration, and at the same time devising new technologies.”

The rover will relay data to Earth through the Trace Gas Orbiter, a spacecraft searching for tiny amounts of gases in the martian atmosphere that might be linked to biological or geological activity since 2016.

Rosalind has already a proposed landing site. Last November a group of experts chose Oxia Planum near the martian equator to explore an ancient environment that was once water-rich and that could have been colonised by primitive life.

On our way to Mars, and back

Looking beyond ExoMars, bringing samples back from Mars is the logical next step for robotic exploration. ESA is already defining a concept for a sample return mission working in cooperation with NASA.

“Returning martian samples is a huge challenge that will require multiple missions, each one successively more complex than the one before,” says David Parker, ESA’s Director of Human and Robotic Exploration.

ExoMars Rover: from concept to reality

“We want to bring the Red Planet closer to home. We want to delve into its mysteries and bring back knowledge and benefits to people on Earth. Returned planetary samples are truly the gift that keeps on giving – scientific treasure for generations to come,” he adds.

Long-term planning is crucial to realise the missions that investigate fundamental science questions like could life ever have evolved beyond Earth?

ESA has been exploring Mars for more than 15 years, starting with Mars Express and continuing with the two ExoMars missions, keeping a European presence at the Red Planet into the next decade.

Related links:

ExoMars: http://www.esa.int/Our_Activities/Human_and_Robotic_Exploration/Exploration/ExoMars

Robotic exploration of Mars: http://exploration.esa.int/

ESA Member States: https://www.esa.int/About_Us/Welcome_to_ESA/New_Member_States

Mars Express: http://www.esa.int/Our_Activities/Space_Science/Mars_Express

Sample return mission: http://www.esa.int/Our_Activities/Human_and_Robotic_Exploration/Exploration/ESA_and_NASA_to_investigate_bringing_martian_soil_to_Earth

Images, Video, Text, Credits: ESA/S. Corvaja/ATG medialab/MRC Laboratory of Molecular Biology.

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Study shows that Vikings enjoyed a warmer Greenland

A new study may resolve an old debate about how tough the Vikings actually were. Although TV and movies paint Vikings as robust souls, braving subzero temperatures in fur pelts and iron helmets, new evidence indicates they might have been basking in 50-degree summer weather when they settled in Greenland.

Study shows that Vikings enjoyed a warmer Greenland
This is a 21st-century reproduction of Thjodhild’s church on Erik the Red’s estate (known as Brattahlíð)
in present day Qassiarsuk, Greenland [Credit: G. Everett Lasher/Northwestern University]

After reconstructing southern Greenland’s climate record over the past 3,000 years, a Northwestern University team found that it was relatively warm when the Norse lived there between 985 and 1450 C.E., compared to the previous and following centuries.

“People have speculated that the Norse settled in Greenland during an unusually, fortuitously warm period, but there weren’t any detailed local temperature reconstructions that fully confirmed that. And some recent work suggested that the opposite was true,” said Northwestern’s Yarrow Axford, the study’s senior author. “So this has been a bit of a climate mystery.”

Now that climate mystery finally has been solved. The study published in the journal Geology. Axford is an associate professor of Earth and planetary sciences in Northwestern’s Weinberg College of Arts and Sciences. The study is a part of Northwestern Ph.D. candidate G. Everett Lasher’s dissertation research, based in Axford’s lab.

To reconstruct past climate, the researchers studied lake sediment cores collected near Norse settlements outside of Narsaq in southern Greenland. Because lake sediment forms by an incremental buildup of annual layers of mud, these cores contain archives of the past. By looking through the layers, researchers can pinpoint climate clues from eons ago.

Study shows that Vikings enjoyed a warmer Greenland
Collected and cleaned chironomid head capsules are prepped for isotope analysis
[Credit: G. Everett Lasher/Northwestern University]

For this study, Lasher analyzed the chemistry of a mix of lake fly species, called chironomids, trapped inside the layers of sediment. By looking at the oxygen isotopes within the flies’ preserved exoskeletons, the team pieced together a picture of the past. This method allowed the team to reconstruct climate change over hundreds of years or less, making it the first study to quantify past temperature changes in the so-called Norse Eastern Settlement.

“The oxygen isotopes we measure from the chironomids record past lake water isotopes in which the bugs grew, and that lake water comes from precipitation falling over the lake,” said Lasher, first author of the paper. “The oxygen isotopes in precipitation are partly controlled by temperature, so we examined the change in oxygen isotopes through time to infer how temperature might have changed.”

Because recent studies concluded that some glaciers were advancing around Greenland and nearby Arctic Canada during the time Vikings lived in southern Greenland, Axford and Lasher expected their data to indicate a much colder climate. Instead, they found that a brief warm period interrupted a consistent cooling climate trend driven by changes in Earth’s orbit.

Near the end of the warm period, the climate was exceptionally erratic and unstable with record high and low temperatures that preceded Viking abandonment of Greenland. Overall, the climate was about 1.5-degrees Celsius warmer than the surrounding cooling centuries. This warmer period was similar to southern Greenland’s temperatures today, which hover around 10-degrees Celsius (50-degrees Fahrenheit) in summer.

In another surprise, Axford and Lasher found that the North Atlantic Oscillation (NAO) — a natural fluctuation in atmospheric pressure that is often responsible for climate anomalies in the region — probably was not in a dominantly positive phase for multiple Medieval centuries as had been hypothesized. (When the NAO is in its positive phase, it brings cold air to much of Greenland.)

“We found that the NAO could not explain Medieval climatic changes at our site,” Lasher said. “That might call into question its use in explaining long-term climate change over the last 3,000 years elsewhere.”

Study shows that Vikings enjoyed a warmer Greenland
An up-close look at a chironomid’s head capsule(center) under a microscope. The Northwestern team isolates
these exoskeletons from sediment cores collected in southern Greenland for oxygen isotope analysis
[Credit: G. Everett Lasher/Northwestern University]

So what did cause the Vikings’ fortuitously warm climate? Lasher and Axford aren’t sure but speculate it might have been caused by warmer ocean currents in the region. The new data will be useful for climate modelers and climate researchers as they seek to understand and predict what might be in store for Greenland’s ice sheet as Earth warms rapidly in the future.

“Unlike warming over the past century, which is global, Medieval warmth was localized,” Axford said. “We wanted to investigate what was happening in southern Greenland at that time because it’s a climatically complex part of the world where counterintuitive things can happen.”

The Norse settlements in Greenland collapsed as local climate apparently became exceptionally erratic, and then ultimately consistently cold. But Axford and Lasher will leave it to the archaeologists to determine whether or not climate played a role in their departure.

“We went in with a hypothesis that we wouldn’t see warmth in this time period, in which case we might have had to explain how the Norse were hearty, robust folk who settled in Greenland during a cold snap,” Lasher said. “Instead, we found evidence for warmth. Later, as their settlements died out, apparently there was climatic instability. Maybe they weren’t as resilient to climate change as Greenland’s indigenous people, but climate is just one of many things that might have played a role.”

Source: Northwestern University [February 06, 2019]



Wadi Al-Hitan “Whales Valley” | #Geology #GeologyPage #Fossil…

Wadi Al-Hitan “Whales Valley” | #Geology #GeologyPage #Fossil #Egypt

Wadi Al-Hitan “Whales Valley” is a paleontological site in the Al Fayyum Governorate of Egypt, some 150 km southwest of Cairo. It was designated a UNESCO World Heritage Site

Photo Copyright © Earth Photo Gallery/Hassan Kasim

Read more & More Photos: http://www.geologypage.com/2012/10/wadi-al-hitan-whales-valley.html

Geology Page



Captioned Image Spotlight (7 February 2019): Wind FlowThe…

Captioned Image Spotlight (7 February 2019): Wind Flow

The atmospheric pressure on Earth at sea level is about 1 bar. On Mars, the pressure is 6 to 10 millibars, or 1/100th that of our planet. But even in this atmosphere, wind still flows around obstacles.

In this image the ripples in the sand tell us which way the wind was moving and how it was diverted around these rock formations.

NASA/JPL/University of Arizona

Earliest known seed-eating perching bird discovered in Fossil Lake, Wyoming

Most of the birds you’ve ever seen–sparrows, finches, robins, crows–have one crucial thing in common: they’re all what scientists refer to as perching birds, or “passerines.” The passerines make up about 6,500 of the 10,000 bird species alive today. But while they’re everywhere now, they were once rare, and scientists are still learning about their origins. In a new paper in Current Biology, researchers have announced the discovery of one of the earliest known passerine birds, from 52 million years ago.

Earliest known seed-eating perching bird discovered in Fossil Lake, Wyoming
The 52-million-year-old fossil of Eofringillirostrum boudreauxi, the earliest known perching bird
with a beak for eating seeds [Credit: (c) Lance Grande, Field Museum]

“This is one of the earliest known perching birds. It’s fascinating because passerines today make up most of all bird species, but they were extremely rare back then. This particular piece is just exquisite,” says Field Museum Neguanee Distinguished Service Curator Lance Grande, an author of the paper. “It is a complete skeleton with the feathers still attached, which is extremely rare in the fossil record of birds.”
The paper describes two new fossil bird species–one from Germany that lived 47 million years ago, and another that lived in what’s now Wyoming 52 million years ago, a period known as the Early Eocene. The Wyoming bird, Eofringillirostrum boudreauxi, is the earliest example of a bird with a finch-like beak, similar to today’s sparrows and finches. This legacy is reflected in its name; Eofringilllirostrum means “dawn finch beak.” (Meanwhile, boudreauxi is a nod to Terry and Gail Boudreaux, longtime supporters of science at the Field Museum.)”

The fossil birds’ finch-like, thick beaks hint at their diet. “These bills are particularly well-suited for consuming small, hard seeds,” says Daniel Ksepka, the paper’s lead author, curator at the Bruce Museum in Connecticut. Anyone with a birdfeeder knows that lots of birds are nuts for seeds, but seed-eating is a fairly recent biological phenomenon. “The earliest birds probably ate insects and fish, some may have been eating small lizards,” says Grande. “Until this discovery, we did not know much about the ecology of early passerines. E. boudreauxi gives us an important look at this.”

Earliest known seed-eating perching bird discovered in Fossil Lake, Wyoming
Researchers in the field at Fossil Lake, Wyoming, prying up a slab of rock containing fossils
[Credit: (c) Lance Grande, Field Museum]

“We were able to show that a comparable diversity of bill types already developed in the Eocene in very early ancestors of passerines,” says co-author Gerald Mayr of the Senckenberg Research Institute in Frankfurt. “The great distance between the two fossil sites implies that these birds were widespread during the Eocene, while the scarcity of known fossils suggests a rather low number of individuals,” adds Ksepka.
While passerine birds were rare 52 million years ago, E. boudreauxi had the good luck to live and die near Fossil Lake, a site famous for perfect fossilization conditions.

“Fossil Lake is a really graphic picture of an entire community locked in stone–it has everything from fishes and crocs to insects, pollen, reptiles, birds, and early mammals,” says Grande. “We have spent so much time excavating this locality, that we have a record of even the very rare things.”

Earliest known seed-eating perching bird discovered in Fossil Lake, Wyoming
Scientists in the field at Fossil Lake, Wyoming, sawing apart rock to free fossils
[Credit: (c) Lance Grande, Field Museum]

Grande notes that Fossil Lake provides a unique look at the ancient world–one of the most detailed pictures of life on Earth after the extinction of the dinosaurs (minus the birds) 65 million years ago. “Knowing what happened in the past gives us a better understanding of the present and may help us figure out where we are going for the future.”

With that in mind, Grande plans to continue his exploration of the locale. “I’ve been going to Fossil Lake every year for the last 35 years, and finding this bird is one of the reasons I keep going back. It’s so rich,” says Grande. “We keep finding things that no one’s ever seen before.”

Source: Field Museum [February 07, 2019]



A long-sighted laser beam

CERN – European Organization for Nuclear Research logo.

7 February, 2019

Image above: Image 1: Example of a transverse cross-section of a beam produced by the structured laser beam. The central axis, which is very dense, is surrounded by several halos of light. The darkness between the halos is absolute, creating a strong contrast. This contrast makes it possible to measure the position of the halos of light with great precision, and thus to validate the measurements using the principle of redundancy. (Image: CERN/IPP).

Sometimes, opportunities fall into our laps when we’re least expecting them. A team of CERN surveyors, in collaboration with the Institute of Plasma Physics in Prague (IPP), has developed a pioneering laser beam while working on a particularly challenging alignment system. “While developing the alignment system for the HIE-ISOLDE accelerator, we discovered that the system generating a structured laser beam had astonishing optical properties”, explain Jean-Christophe Gayde (CERN, EN-SMM-ESA) and Miroslav Šulc (IPP), the system’s inventors. “We didn’t initially plan to develop a generator for this kind of laser beam, but the results of our research were very encouraging.”

Continuing with the “unplanned” project, the two teams developed the “structured laser beam”, which is extremely innovative in that it produces beams that are almost non-diffractive. The central axis of the beams diverges very little, even over a distance of several hundred metres: 200 metres from the system, the central axis of the laser measures only a few millimetres in diameter, hardly more than when it left the generator (see image 2)! The systems available on the market produce such beams over a distance of only a few metres.

Image above: Image 2: Comparison of the central divergence of a non-structured laser beam (left) and a structured laser beam (right), at distances of 0 to 3 metres from the generator. (Image: CERN/IPP).

Its exceptional properties give the structured laser beam potential in many fields, including communication, medicine, physics and, above all, metrology. “At CERN, this laser would be a valuable tool for aligning magnets, thanks to its low central divergence”, says Jean-Christophe Gayde. “And it has one particularly remarkable characteristic: in certain conditions, the beam reconstructs itself after meeting an obstacle. In other words, its halo can reconstruct the central beam after it has passed the obstacle, in a similar way to a Bessel beam.”

The structured laser beam can be produced from source laser beams in a wide range of wavelengths and its geometry can be easily adapted (diameter of the central divergence, number of circles in the halo, etc.). The generator itself can be very compact (the size of a matchbox) and adjustable, while still being fairly inexpensive. “We filed a patent application in May 2018 and since then we’ve been in talks with several potential clients in Europe to establish collaborations”, says Amy Bilton, the knowledge transfer officer (KTO) responsible for the project within CERN’s Knowledge Transfer group. “Studies are ongoing and more tests are needed, but the structured laser beam could considerably improve some applications that use light beams, in particular laser beams.”


CERN, the European Organization for Nuclear Research, is one of the world’s largest and most respected centres for scientific research. Its business is fundamental physics, finding out what the Universe is made of and how it works. At CERN, the world’s largest and most complex scientific instruments are used to study the basic constituents of matter — the fundamental particles. By studying what happens when these particles collide, physicists learn about the laws of Nature.

The instruments used at CERN are particle accelerators and detectors. Accelerators boost beams of particles to high energies before they are made to collide with each other or with stationary targets. Detectors observe and record the results of these collisions.

Related links:

ISOLDE accelerator: https://indico.cern.ch/event/489498/contributions/2217512/attachments/1349763/2044995/HIE_Results_MAT_IWAA2016_Paper.pdf

Plasma Physics in Prague (IPP): http://www.ipp.cas.cz/

Bessel beam: https://en.wikipedia.org/wiki/Bessel_beam

The project within CERN’s Knowledge Transfer group: https://kt.cern/technologies/structured-laser-beam

Large Hadron Collider (LHC): https://home.cern/science/accelerators/large-hadron-collider

For more information about European Organization for Nuclear Research (CERN), Visit: https://home.cern/

Images (mentioned), Text, Credits: CERN/Anaïs Schaeffer.

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Cracking Eggs From malaria to Zika, mosquitoes are infamous…

Cracking Eggs

From malaria to Zika, mosquitoes are infamous vectors of serious diseases, so developing strategies to control their populations would help tackle multiple global health concerns. Recent research on the mosquito Aedes aegypti suggests that this could be achieved by compromising the structure of their eggs. Scientists identified a protein critical to the viability of mosquito eggs, named eggshell organising factor 1 (EOF1). Close-ups under an electron microscope reveal that, compared to healthy eggs (left-hand panels), eggs lacking EOF1 (right) have a different morphology, with larger bumps, or tubercles, on the eggs’ surface. These eggs are also paler, more porous and often collapse, failing to produce viable larvae. As it’s specific to Culex, Aedes and Anopheles mosquitoes, collectively responsible for transmitting several major diseases, disrupting EOF1 and the processes it controls could hopefully reduce mosquito populations without harming other insects, making it a particularly attractive target for future research.

Written by Emmanuelle Briolat

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