This week we will consider a new theory about why Humans are limited to roughly 100 years of live. What is the longevity bottleneck that is stopping us from living longer? We also look at a couple of new innovations in concrete that may make our building last significantly longer. Finally we update happenings in space. The Milky Way is consuming its’ neighbors, Halley’s Comet is now on its’ way back and the US will return to the moon next month.
The Longevity Bottleneck
Why do we humans have a lifespan of roughly 100 years when some other animals show few significant signs of aging and can live longer? A team at the university of Birmingham have developed a possible explanation.
In the Mesozoic Era during the rein of the dinosaurs, mammals faced persistent pressure for food. Over 100 million years they had to reproduce quickly, i.e. before they became lunch for a T-Rex. This pressure over a long period led to the loss or inactivation of genes associated with long life. These genes are related to tissue regeneration and DNA repair.
During this period many mammals were forced to the bottom of the food chain evolving to survive through rapid reproduction. Humans are one of the longest lived mammals however there are many reptiles and other animals with much slower aging processes.
Earth now has many mammals that grow big and live long however they all appear to have the same aging constraint from the Mesozoic era. This may provide another avenue for research for longevity researchers.
Concrete
Self-healing Concrete
Researchers from Drexel University have developed a new way for improving the durability of concrete. Fibre reinforcement of concrete has been around since the early builders mixed horsehair with mud to improve structural integrity of their materials.
The team has taken this idea to the next level by turning reinforcing fibers into a living tissue system that can move concrete healing bacteria to the site of a crack to repair the damage.
In our skin our tissue naturally heals through a multilayer fibrous structure infused with blood (our self healing fluid). This new concept mimics our human capabilities. It uses a biological technique to enable self repair in concrete with the help of bio mineralizing bacteria. The team identified a strain of Lysinibacillus sphaericus bacteria that can act as a bio healing agent for the fibre in concrete.
This bacteria is usually found in the soil and has the ability to drive a process called microbial induced calcium carbonate precipitation to create a stone like material that can stabilize and then harden into a patch for exposed cracks in concrete. When induced into forming an endospore, the bacteria can lie dormant until called into action.
The biofibre is formed from a polymer core capable of stabilising and supporting concrete structures. The biofibre is then coated with a layer of endospore laden hydrogel and encased in a damage responsive polymer shell (like a skin). The whole biofibre is about half a millimeter thick.
The biofibre is placed in a grid when pouring the concrete. The biofibre acts as a reinforcing agent whilst it waits until a crack has penetrated the concrete enough to pierce the fibers outer polymer shell. As water forces its’ way into the biofibre it causes the hydrogel to expand and push its’ way out of the shell and toward the surface of the crack. Then the bacteria jumps into action to repair the crack. Reacting with the concrete the bacteria produce calcium carbonate which acts as a cementing material.
The healing time ultimately depends upon the size of the crack however early indications are that the bacteria could do its’ job in two days. Self healing concrete will reduce the cost of repair and prolong the lifespan of concrete structures.
Smart Concrete
A team from RMIT in Melbourne have added graphene oxide to cement to make a stronger 3D printable concrete that is easier to print. This paves the way to smart walls that can monitor themselves for cracks. The team discovered that Graphene Oxide gave concrete electrical conductivity and increased the strength by up to 10%.
Current detection methods for cracks include ultrasonic or acoustic sensors. These can detect large cracks however smaller newer cracks are a challenge. The equipment is also bulky making regular monitoring expensive and difficult.
By adding the graphene oxide to the concrete the electrical circuits may allow the detection of structural issues, changes in temperature and other environmental factors. The 3D printability may remove the need for formwork which is expensive and labor intensive. In addition more complex structures can be created with less waste.
Some Space Updates
Back to the Moon
On January 25, 2024 a private US company will try and land a craft on the moon. That is more than 50 years since the US’s last visit. Named Peregrine, the craft will be unmanned. Developed by Astrobotic a Pittsburg based company the craft will carry NASA instrument to study the Lunar environment in anticipation of NASA’s Artemis manned missions. Launching sometime after two test missions in 2025 the crew will explore the area near the Moon’s South Pole. It is intended that one of the crew will be the first woman on the Moon.
Halley’s Comet
Readers that are old enough will remember standing outside in early 1986 and seeing Halley’s Comet in the sky. With an orbit that takes 75 years, it is for most, a once in a lifetime experience.
On December 9 this year Halley’s comet reached its’ aphelion (the furthest point from the sun and essentially the mid point of its’ journey). The comet is currently near Jupiter. Only 37 and a bit years till we can once again see the comet in the skies. I am looking forward to seeing it again in 2061.
The Milky Way
Our very own galaxy is on track to devour about 50 dwarf galaxies that currently surround our galaxy. This has happened before and will happen again and again over the next few billion years. The dwarf galaxy known as Sagittarius entered the Milky Way about 5 or 6 billion years ago.
Most dwarf galaxies are star systems that arrived late to the Milky Way. The immense gravitational forces of our galaxy will gradually draw these dwarf galaxies into its control. Unfortunately I doubt that I will be around to see these mergers. However if someone solves the human longevity bottleneck, I may still be here.
Paying it Forward
If you have a start-up or know of a start-up that has a product ready for market please let me know. I would be happy to have a look and feature the startup in this newsletter. Also if any startups need introductions please get in touch and I will help where I can.
If you have any questions or comments please comment below.
I would also appreciate it if you could forward this newsletter to anyone that you think might be interested.
Till next week.