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Cataract: it is waiting for you personally (if you live, of course)

Reading time 10 min
Views 975

This is a model of an intraocular multifocal lens from Carl Zeiss. The real size of such a lens is 11 millimeters, the diameter of the optical zone is 6 mm.

The cataract is, simplifying, age opacification and consolidation of a crystalline lens. According to the classical definition, we are talking about the turbidity of any type. First, something gets in the field of view, a general “fog” appears, you want to wipe dirty glasses, then you do not see the letters in the book, then you want to turn on the light brighter or, on the contrary, you hide from the bright light, and then wake up one fine morning and understand that you can not find slippers. And you see nothing at all — only the shadows. This process sometimes stretches for many years, but slippers are still lost. Mention of clouding that develops in the eyeball, there are still thousands of years before our era.

The treatment procedure has historically been very peculiar — reclination of a cloudy lens. The doctor took the patient with a very dense lens — to that dense stage that the patient is already blind. During the excavations of the settlements of ancient Greece and Rome, the tools used by doctors to remove cataracts were found — sharp needles that pierced the eye and lens, destroying its supporting apparatus. The lens could come off and, by virtue of its gravity, could also fall down from hitting the back of the head with a heavy stick several times. Sometimes the patient died during the emergency eye care, sometimes he had a concussion, and sometimes the lens fell off the ligaments and flew deep into the eye. The patient began to see again — he had a huge lump and vision of about +10 +15 diopters.

Now two news. The bad — people began to live to cataracts more often, and it is inevitable. Good — we have something better than sharp needles and a heavy stick.
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Total votes 3: ↑3 and ↓0 +3
Comments 0

The QC House of Cards

Reading time 4 min
Views 697
There’s Gold in Them Thar Hills

Gold rushes can make people crazy. 1848 was enough of an indicator of that. When Sam Brannan announced to the world: ‘Gold! Gold! Gold from the American River!’, half the world’s population (or so it seemed to the tiny California population which lived there at the time) descended on the soon to be the newest state of the union.

San Francisco, before a small hamlet with a few hundred pioneers living there, became a centre of vice, murder and debauchery overnight.

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Two hundred years before tulip mania hit Europe, and like in California with its argonauts or 49ers, it impoverished more than it made rich. In the early 2000s, too, the Dot.Com bubble created a speculative tendency in people when irrationality took over all reason.
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Total votes 1: ↑0 and ↓1 -1
Comments 0

From four to thirty two. Early years of computers and networks in Russia

Reading time 38 min
Views 1.6K

Part I: From four to eight



I like to read the memoirs of people who observed the computers taking first steps in their countries. They always have something romantic about them. Usually, such memories are greatly influenced by the circumstances of that encounter with his first computer: it could be the workplace, or education establishment, it could be just an unexpected and random thing.

Like many of my friends, I was lucky to see the end of that special romantic period, when computer makers were not trying to please the regular users. They were creating the devices with distinctive and unique features they thought were right for some of reasons. This approach is clear to see in both software and hardware. Such features were making the device to sell in millions or be a commercial failure.

It all started differently for different people. Some of them were working with buzzing massive computers that could fill an entire room, the others had desktop-style home computers. There were people, who made their first computer themselves using specialist magazine publications. Different types of computers created the variety of specific traditions, interests and subcultures.
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Total votes 5: ↑4 and ↓1 +3
Comments 1

IT specialist's vision: what you personally need to know

Reading time 8 min
Views 904


— Which is better: glasses, lenses or laser vision correction?
It is best to see without any means of correction. If you are completely satisfied with the glasses — keep calm, no other correction is needed. Lenses — this method of correction requires adherence to clear rules of use, which is ultimately more costly and risky, but it is very popular because the main dangers do not appear immediately after the start of wearing, but years later.

— I decided to stay on the glasses, but I am afraid that the car's pillow will open in my face and they will become contact lenses. What to do?
In my surgical experience, modern airbags do not injure eyeglasses. Eyes and face are usually damaged by windshield fragments. If you are concerned about the safety of glasses, then think about the modern, with polycarbonate lenses, they are incredibly durable, the car drives on crash tests.

— Is it true that all eye disease from the computer?
No, it's not true. The main cause of problems with optics — myopia, hyperopia or astigmatism — is genetics. Adverse environmental conditions, especially during long-term work at close range, are important in childhood, when the development of the organism is not yet complete. And such diseases as cataract, glaucoma, retinal detachment and other diseases occur with the same frequency in those who work at the computer for hours and in those who do not know where the computer has a power button.
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New lunar landers to be created with the help of additive manufacturing

Reading time 2 min
Views 1K
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The USA's National Aeronautics and Space Administration (NASA) has chosen three private companies to participate in the development of landing modules for the new Artemis lunar program. Among them are two enterprises that widely use 3D printing technologies in the production of rocket engines — Jeff Bezos' Blue Origin and Elon Musk's SpaceX. NASA seems to approach the matter carefully and generously, financing the development of lunar manned vehicles in three competing directions at once.
Total votes 4: ↑4 and ↓0 +4
Comments 1

«Augmentation» eyes: what do we build into it today, and what else will remain under it

Reading time 10 min
Views 1.1K

In surgery, the term «augmentation» is used for a specific type of intervention, for example, hardening (building) the skeleton of an organ. We will talk about the empowerment of biological vision at the expense of implants.

You can not just take out a piece of tissue from the eye, as during laser correction, but also insert something new there. For example, an implant that allows you to see at night. Or DVR. Or — what is being done now — just an internal contact lens made from a biocompatible polymer.

Therefore, when you read about new opportunities for contact lenses, remember — all this can be built into a person. Of the most promising technologies — transfer images from your eyes to a computer and vice versa. If you are lucky, in 10 years you will be able to search for a given word in a paper book, as you are now looking for on a web page.

But let's still go back to the real world and talk about phakic lisch, corrective vision for those who can not help the laser.
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Guide for entrepreneurs to launch an on-demand grocery delivery app amid the coronavirus pandemic

Reading time 4 min
Views 1.2K


After the onset of the coronavirus pandemic, Instacart, a popular online grocery platform, hired 300,000 workers to meet the demands of the people. In addition, they are planning to hire 250,000 more. Such is the demand for online grocery platforms nowadays. People are in self-isolation with restricted outdoor movements. The fear of contracting the disease is so high that people are looking for alternative ways even to access essential services. As a result, smartphone applications are gaining increased attention from people all over the world.
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FAQ about laser correction ReLEx SMILE: yes, in Russia there is, but no, in Russia there isn’t

Reading time 9 min
Views 1.9K


— Are small-invasive laser vision correction operations done in Russia using the Small Incision Lenticule Extraction method?

Yes, about 10 years already. Every year, more and more at conferences of ophthalmologists, questions arise not at the level of “What is this?”, But at specific practical nuances of technology. VisuMax lasers exist in several clinics in Russia, but it is much less used under ReLEx SMILE than under femtoLASIK. Historically, it happened in Russia that this technology is little used in the central part and is actively used beyond the Urals.

— What is the story with licenses for specific operations?

Zeiss sells cones with licenses. A cone — a replacement part adjacent to the eye — is purchased with a license to use a laser procedure, usually in batches of 10 or 100 operations. For example, 10 cones and 10 licenses are received. Licenses are driven through the laser menu, and it allows you to use the appropriate cones for the appropriate program types. Licenses for SMILE separately, for femtoLASIK separately, for FLEX, rings and additional corrections are also separate licenses. Most manufacturers of femtosecond and some excimer lasers have a similar situation. Licenses for excimer operations are not needed, perhaps, except on models of about 5 years old and older.

— And you can not get such a license for SMILE?

Easily. Firstly, this module in the laser is as an expensive option, so the device itself without the SMILE option is cheaper. Secondly, if this option is available, then licenses to carry out the operation ReLEx SMILE can be acquired only after conducting 5–10 test runs on pig eyes, then performing at least 10 femtoLASIK operations on patients, then 50 FLEX operations, and only after that Buy a SMILE license for a specific surgeon.
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Total votes 3: ↑3 and ↓0 +3
Comments 0

A couple more unobvious things that you might not be told before laser vision correction

Reading time 13 min
Views 1K

Today, without the «tin», as you asked

There is already a post about how the laser cuts by creating millions of cavitation bubbles in the cornea layer of the eye, and analyzing telemetry from the real operation in seconds with comments of the surgeon's actions.

Now FAQ about various related things


— If I look away while the laser is running, what will happen?

You simply will not work. In fact, immediately after anesthesia, the eye is pressed against a special pneumocapture. To blink at you too will not leave because of fixing (it is not long and not for long). The only moment where it is possible to seriously disrupt the course of the operation is to pull the head down strongly, pulling it out of the headrest by a serious willed effort. In this case, the operation will instantly stop. More precisely, it will stop even before the loss of capture (details below).

— How should an operating room be prepared?

In general — as a normal operating room, that is, a room with a clean area (air filtration, overpressure to prevent contamination from the outside after cleaning). It is important for the procedure that microparticles of dust flying in the air do not fall between the laser lens and the eye.
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Total votes 3: ↑3 and ↓0 +3
Comments 0

Four Ways Quantum Computing Will Change Artificial Intelligence Forever

Reading time 4 min
Views 1.8K
If science were a dating app, quantum physics and machine learning probably wouldn’t be a match. They’re from completely different fields and often require completely different backgrounds and skills. But, throw in a little quantum computing and, suddenly, that science-matchmaking app becomes Tinder and the attraction between the two is palpable.

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(Credit: cmo.adobe.com/articles/2017/5/how-will-artificial-intelligence-impact-business-tlp-ptr.html#gs.5zlifl)

Even though the extent of change that quantum computing will unleash on AI is up for debate, many experts now more than suspect that quantum computing will definitely alter AI at some level. Analysts from bank holding company BBVA, for example, point toward the natural synergy between quantum computing and AI as reasons why quantum machine learning will eventually best classical machine learning.

“Quantum machine learning can be more efficient than classic machine learning, at least for certain models that are intrinsically hard to learn using conventional computers,” says Samuel Fernández Lorenzo, a quantum algorithm researcher who collaborates with BBVA’s New Digital Businesses area. “We still have to find out to what extent do these models appear in practical applications.”
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Rating 0
Comments 2

Laser telemetry for vision correction: a complete operation with comments (not for the faint of heart)

Reading time 5 min
Views 962
Now I will show what doctors usually never show to patients. More precisely, it shows everything in the form of a beautiful render, from which it does not follow at all that a piece of metal will stick up in your cornea for a couple of minutes. Fortunately, you will not feel this because of the anesthetic premedication, you will not know and do not remember, because the piece of iron will be out of focus.



So, watch the video, and I will show the frames with comments. This is a real operation on a patient in a German clinic, the recording was made on a device like the “black box” of the VisuMAX device. In this case, the patient has agreed to use the recording for training purposes, usually access to such records is strictly limited.
Total votes 6: ↑3 and ↓3 0
Comments 2

Laser that cuts inside the cornea: ReLEx procedure at the physical level

Reading time 6 min
Views 1.8K
The idea — to take and cut a lens in a transparent cornea — is not new. At first it was done manually, with a scalpel directly on the surface (difficult and very rough, with a sea of side effects). The first laser was used in 1979, then it was a pulsed infrared emitter with an effective pulse length of 4 nanoseconds.


Step 1: creating a plasma bubble, in fact — a microburst. Step 2: expansion of the shock and heat waves. Step 3: cavitation bubble (plasma expansion). Step 4: the formation of a parallel slice at the expense of several adjacent laser focus points.

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Total votes 14: ↑11 and ↓3 +8
Comments 8

Agile English teaching. What is it?

Reading time 4 min
Views 2.1K


Modern-day agile English teaching has come to take the place of rigid, cut-and-dried lessons that are fast becoming a thing of the past.

Let me clarify what I mean by agile teaching that is bound to substitute conventional teaching.

Some decades ago and up until recently it was perfectly valid to choose a certain textbook and go through it module by module together with your students (be it a group or individual learners). Given the abundance of high-quality materials readily accessible online and offline, it is completely unthinkable to proceed with this outdated approach.
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Total votes 1: ↑1 and ↓0 +1
Comments 0

Why I keep track of spendings in a personal app made with Git+JS

Reading time 4 min
Views 1.4K

Hi, folks, let me share my experience of creating an application to keep track of my spendings. Specifically, let me do it by answering the following questions:


  1. Why keep track of spendings in an application?
  2. Why did I create the application as a personal project?
  3. Why does the project use Git+JS?

1. Why keep track of spendings in an application?


I, like many people out there, wanted to become rich and successful. To become rich, one is often advised to run a personal budget, that's what I started to do several years ago. I'd like to point out that running my personal budget hasn't made me rich and successful, and I increased income simply by moving to Moscow.

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Could Quantum Computing Help Reverse Climate Change?

Reading time 4 min
Views 984
The unique powers of quantum computation may give humanity an important weapon — or several weapons — against climate change, according to one quantum computer pioneer.
One of the possible solutions for the excess carbon in the atmosphere and to reach global climate goals is to suck it out. It sounds pretty easy, but, in fact, the technology to do so cheaply and easily isn’t quite here yet, according to Jeremy O’Brien Chief Executive Officer, PsiQuantum, a quantum computing startup.

Currently, there is no way to simulate large complex molecules, like carbon dioxide. Current classical computers cannot simulate these types of molecules because the problem grows exponentially with the size or complexity of the simulated molecules, according to O’Brien, who wrote an article outlining the issue at the World Economic Forum’s annual meeting held recently.

“Crudely speaking, if simulating a molecule with 10 atoms takes a minute, a molecule with 11 takes two minutes, one with 12 atoms takes four minutes and so on,” he writes. “This exponential scaling quickly renders a traditional computer useless: simulating a molecule with just 70 atoms would take longer than the lifetime of the universe (13 billion years).”
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Total votes 5: ↑3 and ↓2 +1
Comments 3

Porting packages to buildroot using the Zabbix example

Reading time 16 min
Views 4.6K


The basics of porting


Originally, Buildroot offers a limited number of packages. It makes sense — there is everything you need, but any other packages can be added.


To add a package, create 2 description files, an optional checksum file, and add a link to the package in the general package list. There are hooks at different stages of the build. At the same time, Buildroot can recognize the needed type of packages:

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Total votes 2: ↑2 and ↓0 +2
Comments 0

Blood sugar and COVID-19

Reading time 7 min
Views 2.2K
Novel pandemic is very new for science, often it takes years before scientists prove connection of risk factors and replicate their findings in experimental setups, but it is not the case to wait. I have been observing different facts about COVID-19 and propose “Hypothesis for connection between blood sugar levels and infection”. The only reason I do this now with so many controversies is that I genuinely believe it can save lives. Lives of my friends, and their relatives.

In the article below I summarise my knowledge on infection and immunity, back it up by links to COVID observations of doctors and scientific papers.
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Total votes 3: ↑3 and ↓0 +3
Comments 2

Working with light: Starting your career at ITMO University

Reading time 4 min
Views 1.5K
One of our previous articles featured an overview of our photonics department students’ work lives. Today we’re going to expand on this topic by looking at four related MA programs: “Light Guide Photonics and Programmable Electronics”, “LED technologies and optoelectronics”, “Photonic materials” and “Laser technologies”. We sat down with some of the folks currently enrolled in these programs, as well as recent graduates, to talk about the role ITMO University played in kickstarting their careers.

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Total votes 5: ↑5 and ↓0 +5
Comments 0

Scientists Turn a Quantum Computer into a Time Machine — At least, for a Second…

Reading time 5 min
Views 1.8K
Scientists said they were able to return the state of a quantum computer a fraction of a second into the past, according to a university press release. The researchers, who are from the Moscow Institute of Physics and Technology, along with colleagues from the U.S. and Switzerland, also calculated the probability that an electron in empty interstellar space will spontaneously travel back into its recent past. The study came out recently in Scientific Reports.
“This is one in a series of papers on the possibility of violating the second law of thermodynamics. That law is closely related to the notion of the arrow of time that posits the one-way direction of time: from the past to the future,” commented the study’s lead author Gordey Lesovik, who heads the Laboratory of the Physics of Quantum Information Technology at MIPT.

While the researchers don’t expect you to take a trip back to the high school prom just yet, they added that the time reversal algorithm could prove useful for making quantum computers more precise.

“Our algorithm could be updated and used to test programs written for quantum computers and eliminate noise and errors,” Lebedev explained.

The researchers said that the work builds on some earlier work that recently garnered headlines.

“We began by describing a so-called local perpetual motion machine of the second kind. Then, in December, we published a paper that discusses the violation of the second law via a device called a Maxwell’s demon,” Lesovik said. “The most recent paper approaches the same problem from a third angle: We have artificially created a state that evolves in a direction opposite to that of the thermodynamic arrow of time.”
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Total votes 3: ↑3 and ↓0 +3
Comments 34