Connect with us

Bioengineer

NASA examines Hurricane Delta’s early morning structure

Credit: Credit: UWM/SSEC/CIMSS/William Straka III The NASA-NOAA Suomi NPP satellite provided two nighttime views of Hurricane Delta as it moved…

Published

on

The NASA-NOAA Suomi NPP satellite provided two nighttime views of Hurricane Delta as it moved toward the U.S. Gulf Coast. A moonlit image and an infrared image revealed the extent and organization of the intensifying hurricane.

Satellite Imagery Shows Delta’s Extent

On Oct. 8 at 4:05 a.m. EDT (0805 UTC), the Visible Infrared Imaging Radiometer Suite (VIIRS) instrument aboard NASA-NOAA’s Suomi NPP satellite captured an infrared and nighttime imagery of Hurricane Delta as it moved through the Gulf of Mexico.

One hour before Suomi NPP passed overhead, Delta had winds of 100 mph, making it a Category 2 storm on the Saffir-Simpson Hurricane Wind Scale. “The imagery showed enhanced convection near the center of circulation, though the actual circulation was covered by a central dense overcast (CDO) feature, but the curved bands beyond that, extending all the way to the U.S., can also be seen,” noted William Straka III, researcher at University of Wisconsin – Madison’s Space Science and Engineering Center, Cooperative Institute for Meteorological Satellite Studies, Wisconsin.

“The Waning Gibbous moon (65% illumination) was enough to see both the tropospheric waves as well as the CDO and long ranging feeder bands (of thunderstorms.”

On Oct. 8 at 3:35 a.m. EDT (0735 UTC) NASA’s Aqua satellite analyzed Delta using the Atmospheric Infrared Sounder or AIRS instrument. AIRS found coldest cloud top temperatures as cold as or colder 210 Kelvin minus 81 degrees Fahrenheit (minus 63.1 degrees Celsius). NASA research has shown that cloud top temperatures that cold indicate strong storms that have the capability to create heavy rain. The eye was obscured by high clouds and central dense overcast.

NASA provides all of this data to tropical cyclone meteorologists so they can incorporate it in their forecasts.

NHC forecaster Jack Beven noted, “Satellite imagery shows that Delta is better organized this morning, with the center well embedded in a cold central dense overcast and a hint of an eye developing in the overcast.”

Watches and Warnings on Oct. 8

NOAA’s National Hurricane Center (NHC) has issued various warnings and watches for Delta’s approach to the U.S. mainland.

A Storm Surge Warning is in effect for High Island, Texas to Ocean Springs, Mississippi including Calcasieu Lake, Vermilion Bay, Lake Pontchartrain, Lake Maurepas, and Lake Borgne.

A Hurricane Warning is in effect from High Island, Texas to Morgan City, Louisiana. A Tropical Storm Warning is in effect from west of High Island to San Luis Pass, Texas and from east of Morgan City Louisiana to the mouth of the Pearl River, including New Orleans. A Hurricane Warning is also in effect for Lake Pontchartrain and Lake Maurepas.

A Tropical Storm Watch is in effect from east of the mouth of the Pearl River to Bay St. Louis Mississippi.

Delta’s Status on Oct. 8

At 11 a.m. EDT (1500 UTC), the center of Hurricane Delta was located near latitude 24.0 degrees north and longitude 92.7 degrees west. That is about 400 miles (645 km) south of Cameron, Louisiana. Delta was moving toward the northwest near 14 mph (22 kph), and this motion with a reduction in forward speed is expected today. Reports from NOAA and Air Force Reserve Hurricane Hunter aircraft indicate that maximum sustained winds have increased to near 105 mph (165 kph) with higher gusts. The latest minimum central pressure reported by the Hurricane Hunter aircraft is 968 millibars.

Delta’s Forecast

NHC expects a turn toward the north by late tonight, followed by a north-northeastward motion by Friday afternoon or Friday night. Additional strengthening is forecast, and Delta is expected to become a major hurricane again by tonight. On the forecast track, the center of Delta will move over the central Gulf of Mexico today, over the northwestern Gulf of Mexico on Friday. Some weakening is possible as Delta approaches the northern Gulf coast on Friday, with rapid weakening expected after the center moves inland within the hurricane warning area Friday afternoon or Friday night.

NASA Researches Earth from Space

For more than five decades, NASA has used the vantage point of space to understand and explore our home planet, improve lives and safeguard our future. NASA brings together technology, science, and unique global Earth observations to provide societal benefits and strengthen our nation. Advancing knowledge of our home planet contributes directly to America’s leadership in space and scientific exploration.

###

For updated forecasts, visit: http://www.nhc.noaa.gov

Source: https://bioengineer.org/nasa-examines-hurricane-deltas-early-morning-structure/

nasa-examines-hurricane-delta’s-early-morning-structure

Bioengineer

How do good metals go bad?

New measurements have solved a mystery in solid state physics: How is it that certain metals do not seem to

Published

on

New measurements have solved a mystery in solid state physics: How is it that certain metals do not seem to adhere to the valid rules?

We all have a clear picture in mind when we think of metals: We think of solid, unbreakable objects that conduct electricity and exhibit a typical metallic sheen. The behaviour of classical metals, for example their electrical conductivity, can be explained with well-known, well-tested physical theories.

But there are also more exotic metallic compounds that pose riddles: Some alloys are hard and brittle, special metal oxides can be transparent. There are even materials right at the border between metal and insulator: tiny changes in chemical composition turn the metal into an insulator – or vice versa. In such materials, metallic states with extremely poor electrical conductivity occur; these are referred to as “bad metals”. Until now, it seemed that these “bad metals” simply could not be explained with conventional theories. New measurements now show that these metals are not that “bad” after all. Upon closer inspection, their behaviour fits in perfectly with what we already knew about metals.

Small change, big difference

Prof. Andrej Pustogow and his research group at the Institute for Solid State Physics at TU Wien (Vienna) are conducting research on special metallic materials – small crystals that have been specially grown in the laboratory. “These crystals can take on the properties of a metal, but if you vary the composition just a little bit, we are suddenly dealing with an insulator that no longer conducts electricity and is transparent like glass at certain frequencies,” says Pustogow.

Right at this transition, one encounters an unusual phenomenon: the electrical resistance of the metal becomes extremely large – larger, in fact, than should be possible at all according to conventional theories. “Electrical resistance has to do with the electrons being scattered at each other or at the atoms of the material”, explains Andrej Pustogow. According to this view, the greatest possible electrical resistance should occur if the electron is scattered at every single atom on its way through the material – after all, there is nothing between an atom and its neighbour that could throw the electron off its path. But this rule does not seem to apply to so-called “bad metals”: They show a much higher resistance than this model would allow.

It all depends on the frequency

The key to solving this puzzle is that the material properties are frequency-dependent. “If you just measure the electrical resistance by applying a DC voltage, you only get a single number – the resistance at zero frequency,” says Andrej Pustogow. “We, on the other hand, made optical measurements using light waves with different frequencies.”

This showed that the “bad metals” are not so “bad” after all: At low frequencies they hardly conduct any current, but at higher frequencies they behave as one would expect from metals. The research team considers tiny amounts of impurities or defects in the material, that can no longer be adequately shielded by a metal at the boundary to an insulator, as a possible cause. These defects can cause some areas of the crystal to no longer conduct electricity because there the electrons remain localized in a certain place instead of moving through the material. If a DC voltage is applied to the material so that the electrons can move from one side of the crystal to the other, then virtually every electron will eventually hit such an insulating region and current can hardly flow.

At high AC frequency, on the other hand, every electron moves back and forth continuously – it does not cover a long distance in the crystal because it keeps changing direction. This means that in this case many electrons do not even come into contact with one of the insulating regions in the crystal.

Hope for important further steps

“Our results show that optical spectroscopy is a very important tool for answering fundamental questions in solid-state physics,” says Andrej Pustogow. “Many observations for which it was previously believed that exotic, novel models had to be developed could very well be explained by existing theories if they were adequately extended. Our measurement method shows where the additions are necessary.” Already in earlier studies, Prof. Pustogow and his international colleagues gained important insight into the boundary region between metal and insulator using spectroscopic methods, thus establishing a fundament for theory.

The metallic behaviour of materials subject to strong correlations between the electrons is also particularly relevant for so-called “unconventional superconductivity” – a phenomenon that was discovered half a century ago but is still not fully understood.

###

Contact

Ass. Prof. Dr. Andrej Pustogow

Institute for Solid State Physics

TU Wien

+43 1 58801 13128

[email protected]

http://www.ifp.tuwien.ac.at/forschung/pustogow-research/home

https://www.tuwien.at/en/tu-wien/news/news-articles/news/wie-werden-gute-metalle-schlecht

Right at this transition, one encounters an unusual phenomenon: the electrical resistance of the metal becomes extremely large – larger, in fact, than should be possible at all according to conventional theories. “Electrical resistance has to do with the electrons being scattered at each other or at the atoms of the material”, explains Andrej Pustogow. According to this view, the greatest possible electrical resistance should occur if the electron is scattered at every single atom on its way through the material – after all, there is nothing between an atom and its neighbour that could throw the electron off its path. But this rule does not seem to apply to so-called “bad metals”: They show a much higher resistance than this model would allow.

Source: https://bioengineer.org/how-do-good-metals-go-bad/

how-do-good-metals-go-bad?

Continue Reading

Bioengineer

Solving the puzzle of polymers binding to ice for Cryopreservation

Credit: Credit: University of Warwick Cryoprotectants are used to protect biological material during frozen storage They have to be removed

Published

on

  • Cryoprotectants are used to protect biological material during frozen storage
  • They have to be removed when defrosting, and how much to use and how exactly they inhibit ice recrystallisation is poorly understood
  • The polymer poly(vinyl)alcohol (PVA) is arguably the most potent ice recrystallisation inhibitor and researchers from the University of Warwick have unravelled how exactly it works.
  • This newly acquired knowledge base provides novel guidelines to design the next generation of cryoprotectants

When biological material (cells, blood, tissues) is frozen, cryoprotectants are used to prevent the damage associated with the formation of ice during the freezing process. New polymeric cryoprotectants are emerging, alongside the established cryoprotectants, but how exactly they manage to control ice formation and growth is still largely unknown. This is especially true for PVA, a deceptively simple synthetic polymer that interacts with ice by means of mechanisms that have now been revealed at the atomistic level thanks to researchers from the University of Warwick.

Cryoprotectants are crucial when freezing biological material to lessen the cellular damage involved with the formation of ice. Ice re-crystallization, that is the process by which larger ice crystals grow at the expense of smaller ones, is one of the major issues affecting the current cryopreservation protocols and it is still poorly understood. Researchers from the University of Warwick have investigated how a rather popular polymer with the potential to be used in cryopreservation binds to the growing ice crystals.

In the paper, ‘The atomistic details of the ice recrystallisation inhibition activity of PVA’, published in the journal Nature Communications, researchers from the University of Warwick have found that, contrary to the emerging consensus, shorter or longer polymeric chains of poly(vinyl)alcohol (PVA) all bind to ice.

Up to now, the community has been working under the assumption that short polymers do not bind strongly enough to the ice crystals, but in this work Dr. Sosso and co-workers have demonstrated that it is the subtle balance between these binding interactions and the effective volume occupied by the polymers at the interface with ice that determine their effectiveness in hindering ice re-crystallization.

This work brings together experimental measurements of ice recrystallization inhibition and computer simulations. The latter are invaluable tools to gain microscopic insight into processes such as the formation of ice, as they are able to see what is happening in very fast or very small processes which are hard to see via even the most advanced experimental techniques.

This work sheds new light onto the fundamental principles at the heart of ice re-crystallization, pinpointing design principles that can be directly harnessed to design the next generation of cryoprotectants. This achievement is a testament to the strength of what is affectionately known as ‘Team Ice’ at Warwick, an ever-growing collaborative network with the potential to make a huge impact on many aspects of ice formation, from atmospheric science to medicinal chemistry.

Fabienne Bachtiger, a PhD student working in the research group of Dr. Sosso (Department of Chemistry) who has spearheaded this work, explains:
“We have found that even rather short chains of PVA, containing just ten polymeric units, do bind to ice, and that small block co-polymers of PVA bind too. It is important for the experimental community to know this, as they have been working under different assumptions up to now. In fact, this means we can successfully use much smaller polymers than previously thought. This is crucial information to aid the development of new more active cryoprotectants.”

Dr. Gabriele Sosso, from the Department of Chemistry at the University of Warwick, who is leading a substantial computational effort to investigate the formation of ice in biological matter, points out that:
“With this contribution we have added a crucial piece to the puzzle of how exactly polymeric cryoprotectants interact with growing ice crystals. This is part of a larger body of computational and theoretical work that my group is pursuing with the intent to understand how cryoprotectants work at the molecular level, so as to identify designing principles that can be directly probed by our experimental colleagues. Warwick is the perfect place to further our understanding of ice, and this work showcases the impact of the very exciting collaboration between my research group and the Gibson Group.”

Professor Matthew Gibson, from the Department of Chemistry and Warwick Medical School at the University of Warwick adds: “Ice re-crystallization is a real challenge in cryobiology, leading to damage to cells but also in frozen foods or infrastructure. Understanding how even this ‘simple’ polymer works to control ice re-crystallization is a major step forward to discover new cryoprotectants, and ultimately to use them in the real world.”

###

15 MARCH 2021

  • This newly acquired knowledge base provides novel guidelines to design the next generation of cryoprotectants
  • Source: https://bioengineer.org/solving-the-puzzle-of-polymers-binding-to-ice-for-cryopreservation/

    solving-the-puzzle-of-polymers-binding-to-ice-for-cryopreservation

    Continue Reading

    Bioengineer

    Debris of stellar explosion found at unusual location

    eROSITA space telescope finds largest supernova remnant ever discovered with X-raysCredit: eROSITA/MPE (X-ray), CHIPASS / SPASS / N. Hurley-Walker, ICRAR-Curtin

    Published

    on

    eROSITA space telescope finds largest supernova remnant ever discovered with X-rays

    Credit: eROSITA/MPE (X-ray), CHIPASS / SPASS / N. Hurley-Walker, ICRAR-Curtin (Radio)

    In the first all-sky survey by the eROSITA X-ray telescope onboard SRG, astronomers at the Max Planck Institute for Extraterrestrial Physics have identified a previously unknown supernova remnant, dubbed “Hoinga”. The finding was confirmed in archival radio data and marks the first discovery of a joint Australian-eROSITA partnership established to explore our Galaxy using multiple wavelengths, from low-frequency radio waves to energetic X-rays. The Hoinga supernova remnant is very large and located far from the galactic plane – a surprising first finding – implying that the next years might bring many more discoveries.

    Massive stars end their lives in gigantic supernova explosions when the fusion processes in their interiors no longer produce enough energy to counter their gravitational collapse. But even with hundreds of billions of stars in a galaxy, these events are pretty rare. In our Milky Way, astronomers estimate that a supernova should happen on average every 30 to 50 years. While the supernova itself is only observable on a timescale of months, their remnants can be detected for about 100 000 years. These remnants are composed of the material ejected by the exploding star at high velocities and forming shocks when hitting the surrounding interstellar medium.

    About 300 such supernova remnants are known today – much less than the estimated 1200 that should be observable throughout our home Galaxy. So, either astrophysicists have misunderstood the supernova rate or a large majority has been overlooked so far. An international team of astronomers are now using the all-sky scans of the eROSITA X-ray telescope to look for previously unknown supernova remnants. With temperatures of millions of the degrees, the debris of such supernovae emits high-energy radiation, i.e. they should show up in the high-quality X-ray survey data.

    “We were very surprised that the first supernova remnant popped up straight away,” says Werner Becker at the Max Planck Institute for Extraterrestrial Physics. Named after the first author’s hometown’s Roman name, “Hoinga” is the largest supernova remnant ever discovered in X-rays. With a diameter of about 4.4 degrees, it covers an area about 90 times bigger than the size of the full Moon. “Moreover, it lies very far off the galactic plane, which is very unusual,” he adds. Most previous searches for supernova remnants have concentrated on the disk of our galaxy, where star formation activity is highest and stellar remnants therefore should be more numerous, but it seems that many supernova remnants have been overlooked by this search strategy.

    After the astronomers found the object in the eROSITA all-sky data, they turned to other resources to confirm its nature. Hoinga is – although barely – visible also in data taken by the ROSAT X-ray telescope 30 years ago, but nobody noticed it before due to its faintness and its location at high galactic latitude. However, the real confirmation came from radio data, the spectral band where 90% of all known supernova remnants were found so far.

    “We went through archival radio data and it had been sitting there, just waiting to be discovered,” marvels Natasha Walker-Hurley, from the Curtin University node of the International Centre for Radio Astronomy Research in Australia. “The radio emission in 10-year-old surveys clearly confirmed that Hoinga is a supernova remnant, so there may be even more of these out there waiting for keen eyes.”

    The eROSITA X-ray telescope will perform a total of eight all-sky surveys and is about 25 times more sensitive than its predecessor ROSAT. Both observatories were designed, build and are operated by the Max Planck Institute for Extraterrestrial Physics. The astronomers expected to discover new supernova remnants in its X-ray data over the next few years, but they were surprised to identify one so early in the programme. Combined with the fact that the signal is already present in decades-old data, this implies that many supernova remnants might have been overlooked in the past due to low-surface brightness, being in unusual locations or because of other nearby emission from brighter sources. Together with upcoming radio surveys, the eROSITA X-ray survey shows great promise for finding many of the missing supernova remnants, helping to solve this long-standing astrophysical mystery.

    ###

    Original publication

    W. Becker, N. Hurley-Walker, Ch. Weinberger, L. Nicastro, M. G. F. Mayer, A. Merloni, J. Sanders
    Hoinga – A Supernova Remnant Discovered in the SRG/eROSITA All-Sky Survey eRASS1
    Astronomy & Astrophysics, accepted 12 February 2021

    https://www.mpg.de/16527751/0302-ext0-giant-cloud-found-at-unusual-location-151510-x

    Source: https://bioengineer.org/debris-of-stellar-explosion-found-at-unusual-location/

    debris-of-stellar-explosion-found-at-unusual-location

    Continue Reading

    Title

    Cointelegraph1 hour ago

    Massachusetts regulator seeks to revoke Robinhood’s broker-dealer license

    Massachusetts' securities regulator is seeking to revoke the broker-dealer license of cryptocurrency-friendly stock trading app Robinhood in the state.

    Entrepreneur6 hours ago

    Penny Stocks To Buy For Under $1 On Robinhood

    Are Penny Stocks Under $1 on Robinhood Worth It?

    Crunchbase20 hours ago

    C2i Genomics Secures $100M Note To Detect Tiny Traces of Cancer

    C2i’s cancer diagnostics service uses AI pattern recognition and whole-genome analysis to spot trace amounts of cancer much quicker.

    Blockchain news23 hours ago

    Ethereum’s Upside Appears Limitless as ETH Breaches $2,400 For the First Time Ever

    On-chain metrics provider Santiment has delved deeper into Ethereum’s uptrend and noted that its rally to $3k and beyond looks...

    CNBC1 day ago

    JPMorgan Chase beats profit estimates on strong trading, $5.2 billion release of loan-loss reserves

    JPMorgan posted first-quarter profit of $4.50 a share, much higher than the $3.10 per share expected by analysts surveyed by...

    CNBC2 days ago

    Coinbase drops below debut price

    Coinbase held its direct listing on the Nasdaq on Wednesday, luring public market investors who've been waiting to get into...

    Ventureburn2 days ago

    Joburg healthtech startup secures undisclosed seven-figure funding –

    Quro Medical has secured an undisclosed seven-figure USD amount of funding in a seed round led by Enza Capital and...

    ZDNET2 days ago

    Is there a market for an Apple TV/HomePod Frankenstein?

    Rumors are circulating that Apple is planning to take two devices that aren't selling all that well, and smash them...

    Reuters2 days ago

    Biden set to withdraw U.S. troops from Afghanistan by Sept. 11

    President Joe Biden plans to withdraw the remaining 2,500 U.S. troops from Afghanistan by Sept. 11, 2021, 20 years to...

    Business insider2 days ago

    Annual Report and Sustainability Report 2021: New Wave Group AB

    KUNGÄLV, Sweden, April 14, 2021 /PRNewswire/ -- New Wave Group AB today published the Annual Report and Sustainability Report for...

    Review

      Select language

      Trending