Tag: science

The half-live of facts

i’d love to have expiration dates for facts. would make it much easier to assess whether a piece of data is still good. some fields change every few years, others take centuries. i find it hard to take any non-fiction book older than ~5 years seriously.

Facts change all the time. Smoking has gone from doctor-recommended to deadly. We used to think the Earth was the center of the universe and that Pluto was a planet. For decades, we were convinced that the Brontosaurus was a real dinosaur. In short, what we know about the world is constantly changing.

But it turns out there’s an order to the state of knowledge, an explanation for how we know what we know. Samuel Arbesman is an expert in the field of scientometrics—literally the science of science. Knowledge in most fields evolves systematically and predictably, and this evolution unfolds in a fascinating way that can have a powerful impact on our lives.

Doctors with a rough idea of when their knowledge is likely to expire can be better equipped to keep up with the latest research. Companies and governments that understand how long new discoveries take to develop can improve decisions about allocating resources. And by tracing how and when language changes, each of us can better bridge generational gaps in slang and dialect.

2 ka Silk Road

As early as 1.9 ka BP, the complex of trading networks on sea and land that are known today as the Silk Road ran from Europe, Africa, Arabia, Persia, India, China, Korea, Japan and back again. Traders did local legs of the massive voyage, stopping at market cities to sell their goods which would then be traded again a little further away and so on, until silk from China wound up adorning Roman emperors and Roman gold-flecked glassware jewels ended up the prized possession of a 1.5 ka BP Japanese nobleman.

Precision Medicine

A working model of your body, grounded in your own genome, refreshed continually with measurements from your body’s insides. This information will be collated with readings from millions of other monitored bodies. Software will produce detailed guidance about diet, supplements, exercise, medication, or treatment—guidance based not on the current practice of lumping symptoms together into broad categories of disorders, but on a precise reading of your own body’s peculiarities and its status in real time.

“And at that point you now have, for the first time in history, a scientific basis for medicine.”

turning medicine from craft into science.
2019-02-01:

However, nearly 20 years after the first predictions of dramatic success, we find no impact of the human genome project on the population’s life expectancy or any other public health measure, notwithstanding the vast resources that have been directed at genomics. Exaggerated expectations of how large an impact on disease would be found for genes have been paralleled by unrealistic timelines for success, yet the promotion of precision medicine continues unabated.

The authors of this new paper end by saying that “it is urgent that the biomedical research community reconsider its ongoing obsession with the human genome“, which is strong language. We’ve learned a lot from genomic studies, and we’re still learning more, and it’s not going away. But if by “obsession” they mean trying to apply genomic viewpoints to every problem regardless of suitability, or promising success in some of these programs once we can do just a bit more sequencing – because that’s all they’re lacking – then they have a point. The genome is great, the genome is huge, the genome is important. But it’s not the only great huge important thing out there.

Spinal Cord Regeneration

This is quite possibly world-changing technology.

Tesearchers found that the newly formed fibers bypassed the original spinal lesion and allowed signals from the brain to reach the electrochemically awakened spine. And the signal was sufficiently strong to initiate movement over ground — without the treadmill — meaning the rats began to walk voluntarily towards the reward, entirely supporting their own weight with their hind legs. A severed section of the spinal cord can make a comeback when its own innate intelligence and regenerative capacity is awakened. The study points to a profound change in our understanding of the central nervous system. It is yet unclear if similar rehabilitation techniques could work for humans, but the observed nerve growth hints at new methods for treating paralysis.

2015-09-13:

A 28-year-old who has been paralyzed for more than a decade as a result of a spinal cord injury has become the first person to be able to “feel” physical sensations through a prosthetic hand directly connected to his brain, and even identify which mechanical finger is being gently touched.

2016-04-18:

the first neural bypass for spinal cord injuries that reconnects the brain to muscles, allowing voluntary and functional control of a paralyzed limb by using a patient’s thoughts — no robotic prosthetic arm required.

2016-11-11:

An international team of scientists has used a wireless “brain-spinal interface” to bypass spinal cord injuries in a pair of rhesus macaques, restoring nearly normal intentional walking movement to a temporarily paralyzed leg.

The finding could help in developing a similar system to rehabilitate humans who have had spinal cord injuries.


2018-09-25:

Thomas and Jeff Marquis, who was paralyzed after a mountain biking accident, can now independently walk again after participating in a study at the University of Louisville that was published today in the New England Journal of Medicine. Thomas’ balance is still off and she needs a walker, but she can walk 100m across grass. She also gained muscle and lost the nerve pain in her foot that has persisted since her accident. Another unnamed person with a spinal cord injury can now independently step across the ground with help from a trainer.

2021-01-30:

After 4 months of training—including 2 with stimulation—every person more than doubled their pinching strength. Several doubled their grasping strength. 1 person regained enough dexterity to drive without an assistive device. Another could handle their catheter well enough to insert it on their own. Owen decided to try painting. At the beginning of the experiment, she recalls, “I was like, ‘I can kind of hold a brush and some paints, and why don’t I give this a go?’” So she ordered a paint-by-numbers kit of a portrait of a dog. “It was kind of hard, and I don’t think it turned out very well, but I’m still really impressed by it”.

2022-02-08:

3 people once paralyzed by complete spinal-cord injuries can walk, swim, work the pedals of a bicycle and even paddle canoes, thanks to an implant specifically designed to control movement by mimicking the signals the lower body usually receives from the brain and upper spinal cord. Once the implant was in place, each person could control the pattern of electrical stimulation, using buttons and a tablet to raise or lower each leg, for example. All 3 participants recovered some level of movement within 1 day of activating the implant, including being able to walk on a treadmill while their weight was supported. “The first few steps were incredible — a dream come true!”. The participants were also able to take part in activities such as pedalling a bicycle and performing squats, and to keep their bodies stable while paddling canoes, using the device to guide their muscles through preprogrammed movements.

Exomoons

the first science project i helped fund made its first discovery. so exciting!

As part of the Hunt for the Exomoons with Kepler (HEK) project, the team analyzed recently released Kepler data and identified systems with transiting planets that show transit variations indicative of hidden companions, such as unseen moons or planets. The team identified the Sun-like star known as KOI-872 (KOI stands for Kepler Objects of Interest) as exceptional in that it shows transits with remarkable time variations over 2 hours.