This blog consists of daily news items of interest to followers of QUIDDITY as a qualitatitive method of describing the world. This approach was described by Clive Barker in "The Great and Secret Show" and analyzed in the 149 posts of the QUIDDITY blog of this writer (see link to companion blog).
A pair of researchers has shown that trying to classify groups of numbers called “torsion-free abelian groups” is as hard as it can possibly be.
It is an exceptional problem for
descriptive set theory. See the link to
this Quanta magazine article:
https://www.quantamagazine.org/mathematicians-solve-decades-old-classification-problem-20210805/
From: American Chemical Society
May 5, 2021 -- Coded messages in
invisible ink sound like something only found in espionage books, but in real
life, they can have important security purposes. Yet, they can be cracked if
their encryption is predictable. Now, researchers reporting in ACS
Applied Materials & Interfaces have printed complexly encoded data
with normal ink and a carbon nanoparticle-based invisible ink, requiring both
UV light and a computer that has been taught the code to reveal the correct
messages.
Even as electronic records advance,
paper is still a common way to preserve data. Invisible ink can hide classified
economic, commercial or military information from prying eyes, but many popular
inks contain toxic compounds or can be seen with predictable methods, such as
light, heat or chemicals. Carbon nanoparticles, which have low toxicity, can be
essentially invisible under ambient lighting but can create vibrant images when
exposed to ultraviolet (UV) light -- a modern take on invisible ink. In
addition, advances in artificial intelligence (AI) models -- made by networks
of processing algorithms that learn how to handle complex information -- can
ensure that messages are only decipherable on properly trained computers. So,
Weiwei Zhao, Kang Li, Jie Xu and colleagues wanted to train an AI model to
identify and decrypt symbols printed in a fluorescent carbon nanoparticle ink,
revealing hidden messages when exposed to UV light.
The researchers made carbon
nanoparticles from citric acid and cysteine, which they diluted with water to
create an invisible ink that appeared blue when exposed to UV light. The team
loaded the solution into an ink cartridge and printed a series of simple
symbols onto paper with an inkjet printer. Then, they taught an AI model,
composed of multiple algorithms, to recognize symbols illuminated by UV light
and decode them using a special codebook. Finally, they tested the AI model's
ability to decode messages printed using a combination of both regular red ink
and the UV fluorescent ink. With 100% accuracy, the AI model read the regular
ink symbols as "STOP," but when a UV light was shown on the writing,
the invisible ink illustrated the desired message "BEGIN." Because
these algorithms can notice minute modifications in symbols, this approach has
the potential to encrypt messages securely using hundreds of different
unpredictable symbols, the researchers say.
https://www.sciencedaily.com/releases/2021/05/210505111356.htm
New research published in Nature has revealed the solution to Jupiter’s ‘energy crisis’, which has puzzled astronomers for decades.
From: University of Leicester
August
4, 2021 -- Space scientists at the University of Leicester worked with
colleagues from the Japanese Space Agency (JAXA), Boston University, NASA’s
Goddard Space Flight Center and the National Institute of Information and
Communications Technology (NICT) to reveal the mechanism behind Jupiter’s
atmospheric heating.
Now, using data from the Keck Observatory
in Hawai’i, astronomers have created the most-detailed yet global map of the
gas giant’s upper atmosphere, confirming for the first time that Jupiter’s
powerful aurorae are responsible for delivering planet-wide heating.
Dr James O’Donoghue is a researcher at
JAXA and completed his PhD at Leicester, and is lead author for the research
paper.
He said: “We first began trying to
create a global heat map of Jupiter’s uppermost atmosphere at the University of
Leicester. The signal was not bright enough to reveal anything outside of
Jupiter’s polar regions at the time, but with the lessons learned from that
work we managed to secure time on one of the largest, most competitive
telescopes on Earth some years later.
“Using the Keck telescope we produced
temperature maps of extraordinary detail. We found that temperatures start very
high within the aurora, as expected from previous work, but now we could
observe that Jupiter’s aurora, despite taking up less than 10% of the area of
the planet, appear to be heating the whole thing.
“This research started in Leicester and
carried on at Boston University and NASA before ending at JAXA in Japan.
Collaborators from each continent working together made this study successful,
combined with data from NASA’s Juno spacecraft in orbit around Jupiter and
JAXA’s Hisaki spacecraft, an observatory in space.”
Dr Tom Stallard and Dr Henrik Melin are
both part of the School of Physics and Astronomy at the University of
Leicester. Dr Stallard added: “There has been a very long-standing puzzle in
the thin atmosphere at the top of every Giant Planet within our solar system.
“With every Jupiter space mission, along
with ground-based observations, over the past 50 years, we have consistently
measured the equatorial temperatures as being much too hot.
“This ‘energy crisis’ has been a long
standing issue – do the models fail to properly model how heat flows from the
aurora, or is there some other unknown heat source near the equator?
“This paper describes how we have mapped
this region in unprecedented detail and have shown that, at Jupiter, the
equatorial heating is directly associated with auroral heating.”
Aurorae occur when charged particles are
caught in a planet’s magnetic field. These spiral along the field lines towards
the planet’s magnetic poles, striking atoms and molecules in the atmosphere to
release light and energy.
On Earth, this leads to the
characteristic light show that forms the Aurora Borealis and Australis. At
Jupiter, the material spewing from its volcanic moon, Io, leads to the most
powerful aurora in the Solar System and enormous heating in the polar regions
of the planet.
Although the Jovian aurorae have long
been a prime candidate for heating the planet’s atmosphere, observations have
previously been unable to confirm or deny this until now.
Previous maps of the upper atmospheric
temperature were formed using images consisting of only several pixels. This is
not enough resolution to see how the temperature might be changed across the
planet, providing few clues as to the origin of the extra heat.
Researchers created five maps of the
atmospheric temperature at different spatial resolutions, with the highest
resolution map showing an average temperature measurement for squares two
degrees longitude ‘high’ by two degrees latitude ‘wide’.
The team scoured more than 10,000
individual data points, only mapping points with an uncertainty of less than
five per cent.
Models of the atmospheres of gas giants
suggest that they work like a giant refrigerator, with heat energy drawn from
the equator towards the pole, and deposited in the lower atmosphere in these
pole regions.
These new findings suggest that
fast-changing aurorae may drive waves of energy against this poleward flow,
allowing heat to reach the equator.
Observations also showed a region of
localised heating in the sub-auroral region that could be interpreted as a
limited wave of heat propagating equatorward, which could be interpreted as
evidence of the process driving heat transfer.
Planetary research at the University of
Leicester spans the breadth of Jovian system, from the planet’s magnetosphere
and atmosphere, out to its diverse collection of satellites.
Leicester researchers are members of the
Juno mission made up of a global team astronomers observing the giant planet,
and are leading
Jupiter observations from the forthcoming James Webb Space Telescope.
Leicester also plays a leading role in science and instrumentation on the
European Space Agency (ESA)’s Jupiter Icy Moons Explorer (JUICE), due for
launch in 2022.
‘Global upper-atmospheric heating on
Jupiter by the polar aurorae’ is available in Nature.
Scientists at the University of Bristol have discovered evidence that giraffes are a highly socially complex species
From: University of Bristol
August 3, 2021 -- Traditionally,
giraffes were thought to have little or no social structure, and only
fleeting, weak relationships. However in the last ten years, research has shown
that giraffe social organisation is much more advanced than once thought.
In a paper published today in the
journal Mammal Review, Zoe Muller, of
Bristol’s School
of Biological Sciences, has demonstrated that giraffes spend up to 30% of
their lives in a post-reproductive state. This is comparable to other
species with highly complex social structures and cooperative care, such as
elephants and killer-whales which spend 23% and 35% of their lives in a
post-reproductive state respectively. In these species, it has been
demonstrated that the presence of post-menopausal females offers survival
benefits for related offspring. In mammals - and –ncluding humans - this is
known as the ‘Grandmother hypothesis’ which suggests that females live long
past menopause so that they can help raise successive generations of offspring,
thereby ensuring the preservation of their genes. Researchers propose that the
presence of post-reproductive adult female giraffes could also function in the
same way, and supports the author’s assertion that giraffes are likely to
engage in cooperative parenting, along matrilines, and contribute to the
shared parental care of related kin.
Zoe said: “It is baffling to me that
such a large, iconic and charismatic African species has been understudied
for so long. This paper collates all the evidence to suggest that giraffes are
actually a highly complex social species, with intricate and high-functioning
social systems, potentially comparable to elephants, cetaceans and chimpanzees.
“I hope that this study draws a line in
the sand, from which point forwards, giraffes will be regarded as intelligent,
group-living mammals which have evolved highly successful and complex
societies, which have facilitated their survival in tough, predator-filled
ecosystems.”
For scientists to recognise giraffes as
a socially complex species, Zoe has suggested eight key areas for future
research, including the need to understand the role that older,
post-reproductive adults play in society and what fitness benefits they bring
for group survival.
Zoe added: “Recognising that giraffes
have a complex cooperative social system and live in matrilineal societies will
further our understanding of their behavioural ecology and conservation needs.
“Conservation measures will be more
successful if we have an accurate understanding of the species’ behavioural
ecology. If we view giraffes as a highly socially complex species, this also
raises their 'status' towards being a more complex and intelligent mammal that
is increasingly worthy of protection.”
Paper:
‘A review of the social behaviour of the
giraffe Giraffa camelopardalis: a misunderstood but socially complex species’
in Mammal Review by Zoe Muller and Professor Stephen Harris.
http://www.bristol.ac.uk/news/2021/august/giraffes-socially-complex.html
Boston University astronomers analyzed light data from a piece of supernova shrapnel—a star called LP 40−365—to gain clues about where it came from
From:
Boston University
August
2, 2021 -- About 2,000 light-years away from Earth, there is a star catapulting
toward the edge of the Milky Way. This particular star, known as LP 40−365, is
one of a unique breed of fast-moving stars—remnant pieces of massive white
dwarf stars—that have survived in chunks after a gigantic stellar
explosion.
“This star is moving so fast that it’s
almost certainly leaving the galaxy…[it’s] moving almost two million miles an
hour,” says JJ Hermes, Boston University College of Arts & Sciences
assistant professor of astronomy. But why is this flying object speeding out of
the Milky Way? Because it’s a piece of shrapnel from a past explosion—a cosmic
event known as a supernova—that’s still being propelled forward.
“To have gone through partial detonation
and still survive is very cool and unique, and it’s only in the last few years
that we’ve started to think this kind of star could exist,” says Odelia
Putterman, a former BU student who has worked in Hermes’ lab.
In a new paper published in The
Astrophysical Journal Letters, Hermes and Putterman uncover new
observations about this leftover “star shrapnel” that gives insight to other
stars with similar catastrophic pasts.
Putterman and Hermes analyzed data from
NASA’s Hubble Space Telescope and Transiting Exoplanet Survey Satellite (TESS),
which surveys the sky and collects light information on stars near and far. By
looking at various kinds of light data from both telescopes, the researchers
and their collaborators found that LP 40−365 is not only being hurled out of
the galaxy, but based on the brightness patterns in the data, is also rotating
on its way out.
“The star is basically being
slingshotted from the explosion, and we’re [observing] its rotation on its way
out,” says Putterman, who is second author on the paper.
“We dug a little deeper to figure out
why that star [was repeatedly] getting brighter and fainter, and the simplest
explanation is that we’re seeing something at [its] surface rotate in and out
of view every nine hours,” suggesting its rotation rate, Hermes says. All stars
rotate—even our sun slowly rotates on its axis every 27 days. But for a star
fragment that’s survived a supernova, nine hours is considered relatively
slow.
Supernovas occur when a white dwarf gets
too massive to support itself, eventually triggering a cosmic detonation of
energy. Finding the rotation rate of a star like LP 40−365 after a supernova
can lend clues into the original two-star system it came from. It’s common in
the universe for stars to come in close pairs, including white dwarfs, which
are highly dense stars that form toward the end of a star’s life. If one white
dwarf gives too much mass to the other, the star being dumped on can
self-destruct, resulting in a supernova. Supernovas are commonplace in the
galaxy and can happen in many different ways, according to the researchers, but
they are usually very hard to see. This makes it hard to know which star did the
imploding and which star dumped too much mass onto its star partner.
Based on LP 40−365’s relatively slow
rotation rate, Hermes and Putterman feel more confident that it is shrapnel
from the star that self-destructed after being fed too much mass by its partner,
when they were once orbiting each other at high speed. Because the stars were
orbiting each other so quickly and closely, the explosion slingshotted both
stars, and now we only see LP 40–365.
“This [paper] adds one more layer of
knowledge into what role these stars played when the supernova occurred,” and
what can happen after the explosion, Putterman says. “By understanding what’s
happening with this particular star, we can start to understand what’s
happening with many other similar stars that came from a similar
situation.”
“These are very weird stars,” Hermes
says. Stars like LP 40–365 are not only some of the fastest stars known to
astronomers, but also the most metal-rich stars ever detected. Stars like our
sun are composed of helium and hydrogen, but a star that has survived a
supernova is primarily composed of metal material, because “what we’re seeing
are the by-products of violent nuclear reactions that happen when a star blows
itself up,” Hermes says, making star shrapnel like this especially fascinating
to study.
International research team shows that protein from microbes uses a fraction of the resources of conventional farming
From:
Georg-August-Universitat Gottingen
July
30, 2021 -- Microbes have played a key role in our food and drinks – from
cheese to beer – for millennia but their impact on our nutrition may soon
become even more important. The world is facing growing food challenges as the
human population continues to increase alongside its demand for resource
intensive animal products. If these needs are to be met solely by conventional
agriculture, the environmental cost will be huge. An international research
team led by a Göttingen University alumnus has now shown that using solar-panels
to produce microbial protein – which is rich not just in proteins but also in
other nutrients – is more sustainable, efficient and environmentally friendly
than growing conventional crops. This method uses solar energy, land,
nutrients, and carbon dioxide from the air. Their research was published in
PNAS.
Using computer simulations drawing
directly from laboratory results, the researchers modelled large-scale
microbial food production facilities, which use solar energy, air, water, and
nutrients to grow microbes. The protein-rich biomass is harvested and
processed, and the resulting powder can be used as feed for animals, or as food
for people. The study carried out an analysis of the energy requirements for
each step, from the very start to the end product, taking into account:
electricity generation (from solar panels), electrochemical production of
energy-rich substrate for the microbes, microbe cultivation, harvesting, and
processing the protein-rich biomass. Several types of microbes and growth
strategies were compared in order to identify the most efficient.
The study found that for each kilo of
protein produced, solar-powered microbes require only 10% of the land area
compared to even the most efficient plant crop – soybean. The study calculated
that even in northern climates with less sunshine, the yields of solar-powered
microbial foods could far outproduce staple crops, while minimizing water and
fertilizer use. Importantly, this production could also be located in regions
not suitable for agriculture, such as deserts.
In previous research, the protein from
these types of microbes has shown beneficial effects when fed to livestock and
is already produced at large scale in the EU. “We expect that microbial protein
will also be beneficial as a supplement to our diets, since it provides a
high-quality protein source composed of all essential amino acids, as well as
vitamins and minerals,” explains first author Dorian Leger, who
carried out the work in the MPI of Molecular Plant Physiology while studying at
the University of Göttingen, along with colleagues from Italy and Israel. “This
technology has the potential to support food production while preventing damage
to the environment. Current farming methods contribute to polluted ecosystems
and depleted water reserves worldwide.”
At the moment, 30-40% of the Earth’s
land is used for farming, yet one in ten people are undernourished. Leger says,
“Integrating the cultivation of nutrient-rich microbes with renewable energy
systems, such as solar panels, has the potential to produce more food with less
resources. This could free up vast amounts of agricultural land, and, in
addition, prevent the further destruction of natural ecosystems, thereby making
a valuable contribution to conservation and sustainability whilst promoting
food availability globally.”
Researchers have recently identified a DNA region known as VNTR2-1 that appears to drive the activity of the telomerase gene, which has been shown to prevent aging in certain types of cells.
From: Washington State University
July
23, 2021 -- Knowing how the telomerase gene is regulated and activated and why
it is only active in certain cell types could someday be the key to
understanding how humans age and how to stop the spread of cancer.
A
research team headed by Jiyue Zhu, a professor in the College of Pharmacy and
Pharmaceutical Sciences, recently identified a DNA region known as VNTR2-1 that
appears to drive the activity of the telomerase gene, which has been shown to
prevent aging in certain types of cells. The study was published in the
journal Proceedings of the National Academy of Sciences (PNAS).
The telomerase gene controls the
activity of the telomerase enzyme, which helps produce telomeres, the caps at
the end of each strand of DNA that protect the chromosomes within our cells. In
normal cells, the length of telomeres gets a little bit shorter every time
cells duplicate their DNA before they divide. When telomeres get too short,
cells can no longer reproduce, causing them to age and die. However, in certain
cell types -- including reproductive cells and cancer cells -- the activity of
the telomerase gene ensures that telomeres are reset to the same length when
DNA is copied. This is essentially what restarts the aging clock in new
offspring but is also the reason why cancer cells can continue to multiply and
form tumors.
Knowing how the telomerase gene is
regulated and activated and why it is only active in certain types of cells
could someday be the key to understanding how humans age, as well as how to
stop the spread of cancer. That is why Zhu has focused the past 20 years of his
career as a scientist solely on the study of this gene.
Zhu said that his team's latest finding
that VNTR2-1 helps to drive the activity of the telomerase gene is especially
notable because of the type of DNA sequence it represents.
"Almost 50% of our genome consists
of repetitive DNA that does not code for protein," Zhu said. "These
DNA sequences tend to be considered as 'junk DNA' or dark matters in our
genome, and they are difficult to study. Our study describes that one of those
units actually has a function in that it enhances the activity of the
telomerase gene."
Their finding is based on a series of
experiments that found that deleting the DNA sequence from cancer cells -- both
in a human cell line and in mice -- caused telomeres to shorten, cells to age,
and tumors to stop growing. Subsequently, they conducted a study that looked at
the length of the sequence in DNA samples taken from Caucasian and African
American centenarians and control participants in the Georgia Centenarian
Study, a study that followed a group of people aged 100 or above between 1988
and 2008. The researchers found that the length of the sequence ranged from as
short as 53 repeats -- or copies -- of the DNA to as long as 160 repeats.
"It varies a lot, and our study
actually shows that the telomerase gene is more active in people with a longer
sequence," Zhu said.
Since very short sequences were found
only in African American participants, they looked more closely at that group
and found that there were relatively few centenarians with a short VNTR2-1
sequence as compared to control participants. However, Zhu said it was worth
noting that having a shorter sequence does not necessarily mean your lifespan
will be shorter, because it means the telomerase gene is less active and your
telomere length may be shorter, which could make you less likely to develop
cancer.
"Our findings are telling us that
this VNTR2-1 sequence contributes to the genetic diversity of how we age and
how we get cancer," Zhu said. "We know that oncogenes -- or cancer
genes -- and tumor suppressor genes don't account for all the reasons why we
get cancer. Our research shows that the picture is a lot more complicated than
a mutation of an oncogene and makes a strong case for expanding our research to
look more closely at this so-called junk DNA."
Zhu noted that since African Americans
have been in the United States for generations, many of them have Caucasian ancestors
from whom they may have inherited some of this sequence. So as a next step, he
and his team hope to be able to study the sequence in an African population.
In addition to Zhu, authors on the paper
include co-first authors Tao Xu and De Cheng and others at Washington State
University, as well as their collaborators at Northeast Forestry University in
China; Pennsylvania State University; and North Carolina State University.
Funding for this study came from the
National Institutes of Health's National Institute of General Medical Sciences,
the Melanoma Research Alliance, and the Health Sciences and Services Authority
of Spokane County.
