motd - 04/##/2024
-----------------
04/30/2024 Ive drives, vol. 3:
https://lmnt.me/blog/icons/ive-drives-vol-3.html
04/28/2024 A new instance of primary endosymbiosis:
https://www.independent.co.uk/news/science/algae-evolution-agriculture-plant-history-b2535143.html
"For the first time in at least a billion years, two
lifeforms have merged into a single organism.
The process, called primary endosymbiosis, has only
happened twice in the history of the Earth, with the first
time giving rise to all complex life as we know it through
mitochondria. The second time that it happened saw the
emergence of plants.
Now, an international team of scientists have observed the
evolutionary event happening between a species of algae
commonly found in the ocean and a bacterium.
...
The process involves the algae engulfing the bacterium and
providing it with nutrients, energy and protection in
return for functions that it could not previously perform
- in this instance, the ability to 'fix' nitrogen from
the air.
The algae then incorporates the bacterium as an internal
organ called an organelle, which becomes vital to the
host's ability to function."
04/24/2024 Daniel Webster Wallace:
https://www.texasmonthly.com/being-texan/the-former-slave-who-became-a-cowboy-a-rancher-and-a-texas-legend/
04/21/2024 Largest stellar black hole in the Milky Way:
https://phys.org/news/2024-04-astronomers-largest-black-hole-milky.html
"Astronomers [have] identified the largest stellar black
hole yet discovered in the Milky Way, with a mass 33 times
that of the Sun ... The black hole, named Gaia BH3, was
discovered 'by chance' from data collected by the European
Space Agency's Gaia mission ... [and] is located [] 2,000
light years away from Earth in the Aquila constellation."
04/21/2024 Arabica coffee plants are over 600,000 years old:
https://phys.org/news/2024-04-morning-coffee-hundreds-thousands-years.html
"[R]esearchers ... [have] found that the [arabica] species
emerged around 600,000 years ago through natural
crossbreeding of two other coffee species."
04/21/2024 The forgotten city of Giddan/Eddana (Anqa, Iraq):
https://phys.org/news/2024-04-forgotten-city-identification-dura-europos.html
"The Dura-Europos site in modern-day Syria is famous for
its exceptional state of preservation. ... [T]his
ancient city has yielded many great discoveries, and
serves as a window into the world of the ancient
Hellenistic, Parthian, and Roman periods. ... [T]here is
another city, only some miles down the Euphrates river,
that presents a long-neglected opportunity for study[:] ...
the city of Anqa [] a near mirror image of Dura-Europos,
of the same size, [and] comparable composition ...[.]
...
Anqa is located just across the Syrian border from
Dura-Europos, in the present-day Al-Qaim district of the
Anbar Governorate in Iraq. Its remains include an
identifying tell mound, at the northern end of the site, a
polygonal inner wall circuit, and a large outer defensive
wall, or enceinte. Situated at a point where the Euphrates
floodplain drastically narrows, the city would have
controlled movement between the populous section of the
valley upstream and the trade route downstream linking
Syria, Northern Mesopotamia, and Babylonia, giving it
great strategic and economic significance."
04/19/2024 Nancy Drew - Mystery of the Seven Keys releases on May 7:
https://youtu.be/5B_nRAyXtzQ
04/17/2024 Tungsten semi-carbine (W2C):
https://phys.org/news/2024-04-dimensional-nanomaterial-expansion.html
"Working at Interface Science Western ... [researchers]
formulated two-dimensional nanosheets of tungsten
semi-carbide (or W2C, a chemical compound containing equal
parts of tungsten and carbon atoms), which, when stretched
in one direction, expand perpendicular to the applied
force. This structural design is known as auxetics.
The trick is that the structure of the nanosheet itself
isn't flat. The atoms in the sheet are made of repeating
units consisting of two tungsten atoms for every carbon
atom, which are arranged metaphorically like the dimpled
surface of an egg carton. As tension is applied across the
elastic nanosheet in one direction, it expands out in the
other dimension as the dimples flatten.
Prior to this innovation, there was only one reported
material that could expand by 10% per unit length in this
counter-intuitive way. The Western-engineered tungsten
semi-carbide nanosheet can expand to 40%, a new world
record."
04/15/2024 National laundry day:
https://www.hedgerhumor.com/national-laundry-day/
"I could win the Nobel Peace Prize and not feel as
accomplished as I do when I put the laundry away the
same day that it gets washed."
04/06/2024 A history of source control systems:
https://experimentalworks.net/posts/2024-03-18-a-history-of-vcs-part1/
04/06/2024 Oh my ksh (extensions OpenBSD's ksh):
https://github.com/qbit/ohmyksh
04/05/2024 Cover art for Nancy Drew - Mystery of the Seven Keys:
https://www.herinteractive.com/2024/04/unveiling-the-new-cover-art-for-nancy-drew-mystery-of-the-seven-keys/
04/04/2024 New sunflower family tree:
https://phys.org/news/2024-04-sunflower-family-tree-reveals-multiple.html
"The sunflower family tree has revealed that flower
symmetry evolved multiple times independently, a process
called convergent evolution, among the members of this
large plant family, according to a new analysis.
...
The sunflower head, for example, is actually a composite
composed of multiple much smaller flowers. While the head
is generally radially symmetric - it can be divided into
two equal halves in multiple directions like a starfish or
a pie - the individual flowers can have different forms of
symmetry. According to the new study, bilateral symmetry
- where there is only one line that divides the flower
into two equal halves - has evolved and been lost multiple
times independently in sunflowers over evolutionary
history. The researchers found that this convergent
evolution is likely related to changes in the number of
copies and the expression patterns of the floral
regulatory gene, CYC2."
04/03/2024 Trying out OpenBSD ksh on MacOS
A recent thread on OpenBSD-misc about switching default
shells from ksh to bash, finally gave me the motivation
to try and switch to OpenBSD's ksh on MacOS (I am a long
time bash user):
https://marc.info/?t=171198874500008&r=1&w=2
The most recent OpenBSD ksh (7.4) is available in MacPorts
as 'oksh':
$ sudo port install oksh
On MacOS, OpenBSD's ksh is much smaller than other shells:
$ ls -l /bin/*sh /opt/local/bin/bash /opt/local/bin/oksh | \
sort -n -k5,5 | awk '{ printf("%-20s %8d\n", $NF, $5); }'
/bin/sh* 134000
/opt/local/bin/oksh* 244568
/bin/dash* 307248
/opt/local/bin/bash* 1050385
/bin/csh* 1153408
/bin/tcsh* 1153408
/bin/bash* 1326752
/bin/zsh* 1377520
/bin/ksh* 2598896
Other than perhaps tab-completion of variable names in
emacs mode, I don't see many differences.
04/03/2024 Hexagons are the bestagons (at least for self-assembly):
https://physics.aps.org/articles/v17/s36
"Florian Gartner and Erwin Frey from Ludwig Maximilian
University of Munich simulated self-assembly of
two-dimensional structures with three types of building
blocks: triangles, squares, and hexagons. ... [They] found
that certain shapes were better than others at assembling
into larger structures, as they tended to form
intermediate structures with more bonds around each block.
In particular, hexagonal blocks were the most efficient
building material, forming 1000-piece structures at a rate
that was 10,000 times faster than triangular blocks.
The results are not limited to geometrically simple
shapes. 'Our insights hold relevance beyond these
simplified models, extending to a wide range of biological
and nanotechnological self-assembly processes,' Frey says."
04/03/2024 Predicting primes?
https://phys.org/news/2024-04-breakthrough-prime-theory-primes.html
Older
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