BC TECH

Saved by @ThomassRichards

NotTheMacAnon
@NotTheMacAnon1 4 years, 5 months ago 712 views

Save to PDF Share See On Twitter

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.

More from NotTheMacAnon

NotTheMacAnon
@NotTheMacAnon1

2020 marks the start of the quantum dot revolution.

Completely ignoring the fact that "photocatalytic generation of reactive oxygen species (ROS) from quantum dots (QDs) has been widely reported."

Results: It was found that whereas singlet oxygen (1O2) was not produced by photoexcited QDs, superoxide anion(O2− )and hydroxyl radicals(OH) were generated by QDs, especially in the presence of a physiological concentration of electron donating agent including NADH.

Using cell metabolic activity assays and various probes of ROS generation, the formation of ROS in cellular environments was demonstrated.

Conclusion: Illumination of QD-treated cells and bacteria with light did affect viability. The above results, together with those of assays in the presence of various scavengers of specific ROS, indicate that the formation of ROS by QDs mainly proceeded via electron transfer.

NotTheMacAnon
@NotTheMacAnon1

So where are we at with this virus people?

Advertisement

NotTheMacAnon
@NotTheMacAnon1

Localized Surface Plasmon Resonance - an overview | ScienceDirect Topics

https://t.co/mzS7vVSREJ

https://t.co/353PdAX2fa

https://t.co/3yBImjOdd4

In some cases, almost 100% of the light energy can be converted to the second harmonic frequency. These cases typically involve intense pulsed laser beams passing through large crystals, and careful alignment to obtain phase matching.

NotTheMacAnon
@NotTheMacAnon1

If you shine light of high enough energy on to a metal, electrons will be emitted from the metal.

NotTheMacAnon
@NotTheMacAnon1

During a normal pregnancy, oxidative stress enhances antioxidant mechanisms that are capable of reacting by way of enzyme activity and non-enzyme free radical deactivators. However, pregnancy is also a state in which this adaptation and balance may be easily disrupted.

There is strong evidence that a chronicin flammatory reaction combined with the presence of a local oxidizing environment may play a vital role in the etiology and development of complications during pregnancy.

In late pregnancy, damage to DNA (especially when it is caused by oxidative stress) is associated with pre-eclampsia(PE), intrauterine growth restriction (IUGR), and the death of mothers in developing countries; it largely determines pregnancy – related susceptibility to diseases

The referential values of ROS and NOS and their minimal and safe concentrations or physiologically beneficial concentrations are yet to be determined.

The measurement of oxidative stress in vivo is perceived as controversial,

as the sen-sitivity and specificity of various oxidative stress markers is unknown.. .

More from Tech

Novid Houellebecq (Tha...
@GarouGothic

Ok, here is a thread for you.
What happens when you have:
Netflix
Apple
Amazon
WarnerMedia +
Disney+
SonyCrackle (Reboot)
Verizon All Access (after they buy CBS/Viacom)
UniversalSkyMedia
By 2021
Answer? Internet Slows To A Craw and Dies.
Why?
Bandwidth.

Netflix's gets 35% of all internet traffic.
Now we all know Apple Coming to Netflix Corner.
We know that WarnerMedia Planning One
We Know about Disney+
Now how will the net handle 8 Streaming Platforms all at once?
Answer - IT CANT.

But Novid, the speed, the 4K the all everything?
NOOOOO BUDDY.
Even if you could do it and even if AWS ran six million clouds, The Net Will still slow to a crawl. 35%, goes to nearly 90% if any of the 8 or all of the 8 eat at netflix's numbers.

Oh, they wouldn't be running at once.
FOOL. You forget how bad things were when game of thrones season premieres came around. HBO SERVERS FALL DOWN GO BOOM!

Now see if a season like 2021 come around and they air shows on a same day. It gets crazy. AT&T and others gonna realize they cant build out forever. Something will give and it might be your entertainment consumption big time.

Shaun Russell
@_ShaunRussell

"I really want to break into Product Management"

make products.

"If only someone would tell me how I can get a startup to notice me."

Make Products.

"I guess it's impossible and I'll never break into the industry."

MAKE PRODUCTS.

Courtesy of @edbrisson's wonderful thread on breaking into comics – https://t.co/TgNblNSCBj – here is why the same applies to Product Management, too.

"I really want to break into comics"

make comics.

"If only someone would tell me how I can get an editor to notice me."

Make Comics.

"I guess it's impossible and I'll never break into the industry."

MAKE COMICS.
— Ed Brisson (@edbrisson) December 4, 2018

There is no better way of learning the craft of product, or proving your potential to employers, than just doing it.

You do not need anybody's permission. We don't have diplomas, nor doctorates. We can barely agree on a single standard of what a Product Manager is supposed to do.

But – there is at least one blindingly obvious industry consensus – a Product Manager makes Products.

And they don't need to be kept at the exact right temperature, given endless resource, or carefully protected in order to do this.

They find their own way.

Advertisement

Patrick McKenzie
@patio11

A thread on HN about bad code in legacy projects both makes me think how little we've learned as a discipline over the years and, honestly, how little credit we give ourselves for some pretty major

Fun going down this list and thinking: "Hmm, plausible at a well-run modern software shop", "Hmm, possible, but requires implausible tradeoffs", "Literally disallowed by languages", and "If you were to attempt doing that our test suite wouldn't let you merge."

I think we as an industry celebrate (not quite the right word) failure too much and don't celebrate success nearly enough. There is no DailyWTF for competent execution, word of which generally stays pretty local to the source while incompetence passes into legend.

Alrighty let me try to thread the needle on being the change I want to see in the world while not giving away anything that will get me in trouble:

Ruby has wonderful developer ergonomics. Typed languages are easier for machines to guarantee the correctness of. We built a type checker for Ruby (and I believe it is slated for OSS release sometime).

c.f.

Pete Savin
@pete_savin

Wellcome to our virtual walk from Ambleside to Howtown on Lake Ullswater. I’ve based the route on #HadriansHighWay by @fellranger1 which he uses a variant to the main route. Books can be bought direct or through @VindolandaTrust

A view of #Ambleside from Wansfell our starting point in the heart of the #LakeDistrict @CumbriaMagazine

We can start at the roman fort at the edge of #Windermere. The Romans stated to push into the lakes in the early 90’s AD, this fort dates to the rebuild in Hadrian’s Reign possibly after warfare which brought about #HadriansWall #Ambleside

The #Ambleside posting wasn’t always a peaceful one as the gravestone in the @ArmittMuseum shows one man was killed “in the fort”

Time to leave and head out of town passing this scale model of the famous Bridge House in #Ambleside #virtualwalk

Devdutta
@Devdutta96

Please please please take your cyber security seriously even if you don’t consider yourself a high risk person. Here are a few easy things to start with. 1/n

Switch from WhatsApp to Signal and enable disappearing messages. Most of us cannot stop using WhatsApp entirely but at least turn off back ups to Google Drive or iCloud. 2/n

Do not have private conversations using the messaging service on any social media platform like Facebook, Instagram or Twitter. 3/n

Switch from Gmail to ProtonMail or any other secure email service provider. 4/n

Switch from Google Docs to CryptPad or RiseUp Pad.

You May Also Like

$The Astro Sapien\u2728$

The Astro Sapien✨
@TheAstroSapienn

Here is my Thread on 'Ketu (South Node) Through Nakshatras' The 27 Constellations 🙏❣.

Do check your “Past life Mastery” which KETU Represents🤞🏻.

1. Ketu in Ashwini Nakshatra:

Here native is Great at Financial Planning, Face reading, understanding other’s mind and intention, Driving Fast they don’t like but they are wayyy smooth over driving Fast. This is also great position which can make native Great Surgeon,

Neurologist, Psychologist.
These natives are Selfless and Sacrifice self for others. They gets Fame and Success but they just don’t care.

2. Ketu in Bharani Nakshatra:

They are good at Flirting, Attracting opposite sex, studing ancient subjects. They are also Great at Creativity and Artistic activities. The are lazy but they are really open minded who handles situations really well.

In Past life they have handles many things which is now helping them to make things easier in this life. They are great Leaders too.

They are really good at Hard work and Smart work both. And yes just as Ashwini they don’t much care about Fame and Success!

WORLD OF SANATAN DHARM...
@world_sanatan

MINUTE DETAILS ABOUT THE ATTACK ON SHAISTA KHAN AT LAL MAHAL

Remarkable Commando op

A long 🧵 but worth your time

Aurangzeb sent his maternal uncle Shaista Khan with powerful army over 1,50,000 on the request of Badibegum Sahiba, Adilshahi sultanate

1/

Shaista Khan entered Deccan to kill Chhatrapati Shivaji Maharaj & to destroy his empire. Shahista Khan captured a lot of province and fort of Chakan near Pune.

2/

Till 3 years he gave lot of troubles to the subjects of Chhatrapati Shivaji Maharaj and he personally made Lal Mahal his destination to live at , which was the property of Chhatrapati Shivaji Maharaj . Lal Mahal, where Chhatrapati Shivaji Maharaj spent his childhood.

3/

1. In the April 1663 Chhatrapati Shivaji Maharaj personally made a surprise attack on Shahista Khan in the Lal Mahal Pune.

2. Chhatrapati Shivaji Maharaj attacked with 300 soldiers at the midnight while Lal Mahal had strong security of 1.5 lac soldiers for Shahista Khan.

4/

3. He entered in Pune, he made a drama of wedding ceremony to enter in Pune near Lal Mahal.

4. During the night they made big hole at the wall of Lal Mahal and entered into the palace.

5/

Advertisement

foone
@Foone

It is 2018 and this error message is a mistake from 1974.
This limitation, which is still found in the very latest Windows 10, dates back to BEFORE STAR WARS. This bug is as old as Watergate.

When this was developed, nothing had UPC codes yet because they'd just been invented.
Back when this mistake was made, There was only one Phone Company, because they hadn't been broken up yet. Ted Bundy was still on the loose. Babe Ruth's home run record was about to fall.

When this bug was developed, Wheel of Fortune hadn't yet aired. No one had seen Rocky Horror. Steven Spielberg was still a little-known directory of TV films and one box-office disappointment. SNL hadn't aired yet. The Edmund Fitzgerald was still hauling iron ore.

WHEN THIS STUPID MISFEATURE WAS INVENTED, THE GODFATHER PART II HAD JUST OPENED IN THEATERS.

So, why does this happen? So Unix (which was only 5 years old at this point) had the good idea of "everything is a file" which mean you could do things like write to sockets, pipes, the console, etc with the same commands and instructions.

Professor
@DillikiBiili

Some ofthe biggest breakouts occur after Volatility Contraction, the analogy is that more a spring is pressed, higher it jumps whenever it gets released.

There is a VCP Scanner on chartink (Not mine). This may also be used to find potential Breakouts.

$Vibhu Vashisth \U0001f1ee\U0001f1f3$

Vibhu Vashisth 🇮🇳...
@VIBHU_Tweet

Did you know?

Rani Bhabani was the Queen of Natore, Bengal or 'Natorer Rani' as she was famously called. She made great contributions in Tarapith & renovated Benaras.

In Varanasi, Durga Kund Mandir was constructed by Rani Bhabani in the 18th century.

Born in Chhatimgram village, Bogra District,Her father's name was Atmaram Choudhury.Bhabani was married off to Raja Ramkanta Moitra,the then zamindar of Rajshahi.After his death, Bhabani became the zamindar, and started being referred to as Rani.She was known as Ardhabangeshwari.

A woman as a zamindar was extremely rare in those days, but Rani Bhabani managed the vast Rajshahi zamindari most efficiently and effectively for over four decades.
Maharani Bhavani was very pious in her personal life. She passed her life in a strict disciplined way.

She conducted the administrative work skillfully. As a Maharani she was an impartial judge. Rani Bhavani had a very hard time during the fag end of her life. The Zamindari (estate) incurred serious loss due to the change of the revenue policy of the company.

In spite of being the owner of a large Zamindari (estate), she had to depend on the stipend of the government in the later part of her life. The amount of this stipend gradually decreased and became Rs. 1000/- only in the end.