In continuum mechanics, stress is a physical quantity that expresses the internal forces that neighbouring particles of a continuous material exert on each other, while strain is the measure of the deformation of the material.

For example, when a solid vertical bar is supporting an overhead weight, each particle in the bar pushes on the particles immediately below it. When a liquid is in a closed container under pressure, each particle gets pushed against by all the surrounding particles.
The container walls and the pressure-inducing surface (such as a piston) push against them in (Newtonian) reaction.
These macroscopic forces are actually the net result of a very large number of intermolecular forces and collisions between the particles in those molecules. Stress is frequently represented by a lowercase Greek letter sigma (σ).
Residual stresses inside a plastic protractor are revealed by the polarized light.
Strain inside a material may arise by various mechanisms, such as stress as applied by external forces to the bulk material (like gravity) or to its surface (like contact forces, external pressure, or friction).
Any strain (deformation) of a solid material generates an internal elastic stress, analogous to the reaction force of a spring, that tends to restore the material to its original non-deformed state.
In liquids and gases, only deformations that change the volume generate persistent elastic stress.
However, if the deformation changes gradually with time, even in fluids there will usually be some viscous stress, opposing that change. Elastic and viscous stresses are usually combined under the name mechanical stress.
Significant stress may exist even when deformation is negligible or non-existent (a common assumption when modeling the flow of water). Stress may exist in the absence of external forces; such built-in stress is important, for example, in prestressed concrete and tempered glass.
Stress may also be imposed on a material without the application of net forces, for example by changes in temperature or chemical composition, or by external electromagnetic fields (as in piezoelectric and magnetostrictive materials).
Virial stress 🧐 is a measure of mechanical stress on an atomic scale for homogeneous systems.

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https://t.co/0ywQ1y5NDj

Pott found an association between exposure to soot and a high incidence of scrotal skin cancer in chimney sweeps. This cancer is now known as Pott's or chimney sweep cancer.

Coal contains trace amounts of naturally-occurring radioactive elements. The process of burning coal at coal-fired power plants, called combustion, creates wastes that contain small amounts of naturally-occurring radioactive material (NORM).

Fly ash particles (a major component of coal ash) can become lodged in the deepest part of your lungs, where they trigger asthma, inflammation and immunological reactions.

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These past few days I've been experimenting with something new that I want to use by myself.

Interestingly, this thread below has been written by that.

Let me show you how it looks like. 👇🏻


When you see localhost up there, you should know that it's truly an experiment! 😀


It's a dead-simple thread writer that will post a series of tweets a.k.a tweetstorm. ⚡️

I've been personally wanting it myself since few months ago, but neglected it intentionally to make sure it's something that I genuinely need.

So why is that important for me? 🙂

I've been a believer of a story. I tell stories all the time, whether it's in the real world or online like this. Our society has moved by that.

If you're interested by stories that move us, read Sapiens!

One of the stories that I've told was from the launch of Poster.

It's been launched multiple times this year, and Twitter has been my go-to place to tell the world about that.

Here comes my frustration.. 😤
Recently, the @CNIL issued a decision regarding the GDPR compliance of an unknown French adtech company named "Vectaury". It may seem like small fry, but the decision has potential wide-ranging impacts for Google, the IAB framework, and today's adtech. It's thread time! 👇

It's all in French, but if you're up for it you can read:
• Their blog post (lacks the most interesting details):
https://t.co/PHkDcOT1hy
• Their high-level legal decision: https://t.co/hwpiEvjodt
• The full notification: https://t.co/QQB7rfynha

I've read it so you needn't!

Vectaury was collecting geolocation data in order to create profiles (eg. people who often go to this or that type of shop) so as to power ad targeting. They operate through embedded SDKs and ad bidding, making them invisible to users.

The @CNIL notes that profiling based off of geolocation presents particular risks since it reveals people's movements and habits. As risky, the processing requires consent — this will be the heart of their assessment.

Interesting point: they justify the decision in part because of how many people COULD be targeted in this way (rather than how many have — though they note that too). Because it's on a phone, and many have phones, it is considered large-scale processing no matter what.

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