Giampaolo Mancini

@mancho_z

Dad of 2, founder at Placejam, starter at The Coding Circus, tech evangelist, digital extremist – Code is in the eye of the beholder –

Turin, Italy

Joined November 2007

1.8K Following

675 Followers

3.6K Posts

mancho_z retweeted

Science girl

@sciencegirl

almost 3 years ago

what addiction may feel like 📹 Nuggets by Film Bilder Studio

mancho_z retweeted

Dreamtonics @dreamtonics_en

almost 3 years ago

We have partnered with Native Instruments to bring you Synthesizer V Studio bundles, perfect for elevating your music production experience. These are available from October 30 to November 9 via the Native Instruments store. Don't miss this chance to try our singing synth!

dreamtonics_en's tweet photo. We have partnered with Native Instruments to bring you Synthesizer V Studio bundles, perfect for elevating your music production experience. These are available from October 30 to November 9 via the Native Instruments store.

Don't miss this chance to try our singing synth! https://t.co/T1oJJ6Kh1J

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mancho_z retweeted

Daniel Vassallo

@dvassallo

almost 3 years ago

I learned a lot about the heart over the last 2 weeks, and discovered an amazing similarity between our heart and distributed computer systems. Let me show you how our heart deals with the CAP theorem. Here's my story: Starting in August, I increased my exercise volume to try to make up for some fitness I lost during the summer. For the 6 weeks that followed I averaged 60min of cardio per day, mostly cycling and running. My average before that was ~30min/day. About 70% was low intensity (Z2-Z3), and 30% high (Z4-Z5). In mid September, I felt something strange when I was in bed at night. My heart rate felt slower, and it felt kind of relaxing. At the time, I thought this was a good thing. I also noticed that the Heart Variability Rate on my Apple Watch shot up by 150% from Sep 10. I didn't make the link with the above though. I had opted into the latest watchOS beta and I suspected it was due to a bug or an algorithm change. I felt the same thing in bed for the rest of the week. Then it disappeared for a week. Then it came back the week after. But this time I was feeling it more frequently. I would be quiet at my desk, and I'd occasionally feel a 2 second delay between beats, followed by a big pounding beat. In the meantime, my fitness was improving. I was doing personal best times in 3 mile runs and 6 mile bike rides. I felt very good when exercising and I didn't notice anything wrong with my heart rhythm when it was elevated during exercise. But towards the start of October, these abnormal beats became too frequent to ignore. They were even starting to affect my sleep. On Oct 1, I did an ECG Afib test on my Apple Watch and it came "Inconclusive". I had never seen that outcome before. I repeated it a dozen times, and it kept arriving to the same result. The next day, I did a brief workout and after my heart rate was down to ~80bpm I repeated the Afib test. It came positive: The next day I went to my doctor and get hooked up on a 12-lead EKG. Within just one 10 second sample, we caught one of abnormal beats. It wasn't Afib, luckily. The diagnosis from the EKG monitor was "Premature Ventricular Contraction", which was confirmed by a radiologist a day later: My doctor told me this is usually a benign thing... unless it was "too frequent", which would be above 10,000 PVCs per day. I did some quick math in my head, and I was sure I was at that threshold or thereabouts. Doctor still tried to reassure me, but when I went home I did some research and found several recent studies which linked a PVC burden of just 70 events per day to significant increases in mortality, cardiovascular events, sudden cardiac arrests, heart attacks, dangerous arrhythmias, stokes, and may other bad things. One study that followed up with 7,500 participants with no known cardiovascular disease found that 75% of those who had shown shown one PVC event on an EKG (like me) were dead after 18 years, while only 20% from the control group with no PVC had died. The studies on athletes with PVC were even more concerning, with some strong links to sudden death. My doctor gave me a 14 day heart rate monitor, which was going to count all PVC events, and the circumstances in which they happen. As a precaution, I stopped all my exercise. Yet, the frequency of my PVCs keep increasing until Oct 11, where they were happening every 4 or 5 beats. Because of the very evident high frequency, I got to do a bunch of other tests to try to rule out any damage in the heart that might be causing them. First, was blood work. It looked for electrolyte imbalance, inflammation markers, thyroid issues, and a few other things. All came normal. Then I did an echocardiogram (ultrasound) of the heart and main arteries. It found everything normal. The left atrium had slightly higher volume than normal, but all the wall thicknesses were normal. There were no signs of inflammation (one of the covid risks that could last several months), the valves were working well, and my ejection fraction (the amount of blood the heart pumps each time it beats) was calculated to 60-65%, which is good. No plaque or narrowing of the arteries. No heart visible damage. Then I also did a CT coronary angiogram. My LDL cholesterol level has always been borderline or slightly elevated, and this test would look for any blockages in the vessels that supply oxygen to the heart. The test produces a 3D imagine of the heart and the blood flow gets enhanced with a contrast dye that looks bright on the CT scan. This also went well. No narrowing was found, and my calcium score was zero. My risk of heart attack within the next 5yrs was zero according to the radiologist. And finally I got another EKG which shed some light on what was actually happening. This time the EKG finding was "Incomplete Right Bundle Branch Block", which in the original EKG was either missed, or the signal was disrupted by the PVC event. This is when there's a reduction of electrical conductivity in the wall that separates the left and right ventricles. It can lead to all sorts of bad things, but mine is considered a benign variant (based on other signs on the EKG), and something that 35-50% of endurance athletes have developed. There are no known harmful outcomes for the variant I have (good news), and it usually disappears when people stop exercising for a couple of months. So here's what's likely happening: The contractions of our heart are not controlled by the central nervous system, like most of our other muscles. Instead, the heart is able to generate its own spontaneous electrical activity to activate its muscles in a fully autonomous and decentralized manner. The master pacemaker for the electrical activity to start and generate the heartbeat contractions is called the SA node, which sits at the top of the heart. When it generates activity, the top 2 chambers of the heart (atria) contract to push blood to the lower ventricles where the main pumping function happens. But the lower ventricles should only contract after a small delay, or else the blood wouldn't have enough time to make it from the atria to the ventricles. So the SA node only activates the atrial muscles (not the lower ventricles), and the electrical activity gets absorbed by a secondary pacemaker structure called the AV node. The AV node delays the conduction for about a tenth of a second (enough time for blood to move from the top to bottom chambers), and then it forwards the electrical activity through the middle wall and down to the ventricles. The ventricles then contract which push blood to the body and lungs, and the cycle repeats itself. (I'm simplifying A LOT of course.) What's interesting is that the AV node can also act like a backup pacemaker if the SA node doesn't do its job. If the SA node doesn't initiate a heart beat for some reason, the AV node will initiate its own electrical activity, contract the atria, and send the electrical activity down to the ventricles for them to contract. What's even more fascinating is that this system is completely decentralized. There is no "brain" watching for missed SA node activity to failover to pacemaking function to the AV node. Instead, there's a hierarchy of several fallbacks (not just SA and AV nodes), and they all watch each other. If they never see activity from the higher up node, they start their own heart beat. The way it works is quite simple. The master SA node is configured to beat at, say, 1000ms intervals. The AV node is configured to beat at 1200ms intervals. When the AV node receives electricity from the SA node, it resets its timer. So basically, if the AV node fails to hear anything from the SA node in 1200ms, it would start its own heart beat. But the redundancy doesn't stop with the SA node and AV node. There are actually 3 other parts of the heart that have the automaticity to trigger a heart beat on their own if none of the other nodes do their job. Just like the AV node runs at a slower frequency than the SA node, all the other fallback structures run at increasingly slower rates. Then when they receive electricity from up the hierarchy, they all reset their timer at the same time without triggering a beat. Here's an illustration of all the conductivity structures and their location. All of these except 2 and 7 have the capability to trigger a heart beat, but in normal conditions 1 is the true pacemaker: So here's what seems to have happened to me: Because of my increased exercise load, my heart did some cardiac remodeling to adapt to the increased demand. The left atrium increased in volume (confirmed by the ultrasound), which compressed the cells of structure 5 (the bundle branches). This compression led to slightly slower conduction velocity, which means that structure 6 was receiving the electrical activity a bit later than normal. And when this delay happened to be a bit too late, it thinks that the heart beat didn't happen and spontaneously triggers its own beat. This is the PVC deflection shown in my original EKG. When this structure triggers its premature beat, there would be almost no blood in the heart (because a regular beat would have just happened a few milliseconds earlier). But since this generates new electrical activity, all the other pacemaking structures reset their timers, and that's how I end up with a skipped heart beat. Then the beat that comes after the skipped beat finds the heart with significantly more blood than usual, which causes the pounding sensation that was making it hard for me to sleep at night. Basically, in terms of the CAP theorm, my heart experienced a partitioning problem. One part of the heart wasn't aware of the real state of the system. But the heart is designed for max availability over consistency, so when in doubt, it triggers a beat. For a full cardiac arrest to happen, all 5 pacemakers or conduction pathways need to fail. The heart is an AP system (highly available and partition loss tolerant, over perfect consistency). Pretty remarkable.

dvassallo's tweet photo. I learned a lot about the heart over the last 2 weeks, and discovered an amazing similarity between our heart and distributed computer systems. Let me show you how our heart deals with the CAP theorem.

Here's my story:

Starting in August, I increased my exercise volume to try to make up for some fitness I lost during the summer. For the 6 weeks that followed I averaged 60min of cardio per day, mostly cycling and running. My average before that was ~30min/day. About 70% was low intensity (Z2-Z3), and 30% high (Z4-Z5).

In mid September, I felt something strange when I was in bed at night. My heart rate felt slower, and it felt kind of relaxing. At the time, I thought this was a good thing.

I also noticed that the Heart Variability Rate on my Apple Watch shot up by 150% from Sep 10. I didn't make the link with the above though. I had opted into the latest watchOS beta and I suspected it was due to a bug or an algorithm change.

I felt the same thing in bed for the rest of the week. Then it disappeared for a week. Then it came back the week after. But this time I was feeling it more frequently. I would be quiet at my desk, and I'd occasionally feel a 2 second delay between beats, followed by a big pounding beat.

In the meantime, my fitness was improving. I was doing personal best times in 3 mile runs and 6 mile bike rides. I felt very good when exercising and I didn't notice anything wrong with my heart rhythm when it was elevated during exercise.

But towards the start of October, these abnormal beats became too frequent to ignore. They were even starting to affect my sleep. On Oct 1, I did an ECG Afib test on my Apple Watch and it came "Inconclusive". I had never seen that outcome before. I repeated it a dozen times, and it kept arriving to the same result. The next day, I did a brief workout and after my heart rate was down to ~80bpm I repeated the Afib test. It came positive:

The next day I went to my doctor and get hooked up on a 12-lead EKG. Within just one 10 second sample, we caught one of abnormal beats. It wasn't Afib, luckily. The diagnosis from the EKG monitor was "Premature Ventricular Contraction", which was confirmed by a radiologist a day later:

My doctor told me this is usually a benign thing... unless it was "too frequent", which would be above 10,000 PVCs per day. I did some quick math in my head, and I was sure I was at that threshold or thereabouts. Doctor still tried to reassure me, but when I went home I did some research and found several recent studies which linked a PVC burden of just 70 events per day to significant increases in mortality, cardiovascular events, sudden cardiac arrests, heart attacks, dangerous arrhythmias, stokes, and may other bad things. One study that followed up with 7,500 participants with no known cardiovascular disease found that 75% of those who had shown shown one PVC event on an EKG (like me) were dead after 18 years, while only 20% from the control group with no PVC had died. The studies on athletes with PVC were even more concerning, with some strong links to sudden death.

My doctor gave me a 14 day heart rate monitor, which was going to count all PVC events, and the circumstances in which they happen.

As a precaution, I stopped all my exercise. Yet, the frequency of my PVCs keep increasing until Oct 11, where they were happening every 4 or 5 beats. Because of the very evident high frequency, I got to do a bunch of other tests to try to rule out any damage in the heart that might be causing them.

First, was blood work. It looked for electrolyte imbalance, inflammation markers, thyroid issues, and a few other things. All came normal.

Then I did an echocardiogram (ultrasound) of the heart and main arteries. It found everything normal. The left atrium had slightly higher volume than normal, but all the wall thicknesses were normal. There were no signs of inflammation (one of the covid risks that could last several months), the valves were working well, and my ejection fraction (the amount of blood the heart pumps each time it beats) was calculated to 60-65%, which is good. No plaque or narrowing of the arteries. No heart visible damage.

Then I also did a CT coronary angiogram. My LDL cholesterol level has always been borderline or slightly elevated, and this test would look for any blockages in the vessels that supply oxygen to the heart. The test produces a 3D imagine of the heart and the blood flow gets enhanced with a contrast dye that looks bright on the CT scan. This also went well. No narrowing was found, and my calcium score was zero. My risk of heart attack within the next 5yrs was zero according to the radiologist.

And finally I got another EKG which shed some light on what was actually happening. This time the EKG finding was "Incomplete Right Bundle Branch Block", which in the original EKG was either missed, or the signal was disrupted by the PVC event. This is when there's a reduction of electrical conductivity in the wall that separates the left and right ventricles. It can lead to all sorts of bad things, but mine is considered a benign variant (based on other signs on the EKG), and something that 35-50% of endurance athletes have developed. There are no known harmful outcomes for the variant I have (good news), and it usually disappears when people stop exercising for a couple of months.

So here's what's likely happening:

The contractions of our heart are not controlled by the central nervous system, like most of our other muscles. Instead, the heart is able to generate its own spontaneous electrical activity to activate its muscles in a fully autonomous and decentralized manner. The master pacemaker for the electrical activity to start and generate the heartbeat contractions is called the SA node, which sits at the top of the heart. When it generates activity, the top 2 chambers of the heart (atria) contract to push blood to the lower ventricles where the main pumping function happens. But the lower ventricles should only contract after a small delay, or else the blood wouldn't have enough time to make it from the atria to the ventricles. So the SA node only activates the atrial muscles (not the lower ventricles), and the electrical activity gets absorbed by a secondary pacemaker structure called the AV node. The AV node delays the conduction for about a tenth of a second (enough time for blood to move from the top to bottom chambers), and then it forwards the electrical activity through the middle wall and down to the ventricles. The ventricles then contract which push blood to the body and lungs, and the cycle repeats itself. (I'm simplifying A LOT of course.)

What's interesting is that the AV node can also act like a backup pacemaker if the SA node doesn't do its job. If the SA node doesn't initiate a heart beat for some reason, the AV node will initiate its own electrical activity, contract the atria, and send the electrical activity down to the ventricles for them to contract. What's even more fascinating is that this system is completely decentralized. There is no "brain" watching for missed SA node activity to failover to pacemaking function to the AV node. Instead, there's a hierarchy of several fallbacks (not just SA and AV nodes), and they all watch each other. If they never see activity from the higher up node, they start their own heart beat.

The way it works is quite simple. The master SA node is configured to beat at, say, 1000ms intervals. The AV node is configured to beat at 1200ms intervals. When the AV node receives electricity from the SA node, it resets its timer. So basically, if the AV node fails to hear anything from the SA node in 1200ms, it would start its own heart beat.

But the redundancy doesn't stop with the SA node and AV node. There are actually 3 other parts of the heart that have the automaticity to trigger a heart beat on their own if none of the other nodes do their job. Just like the AV node runs at a slower frequency than the SA node, all the other fallback structures run at increasingly slower rates. Then when they receive electricity from up the hierarchy, they all reset their timer at the same time without triggering a beat.

Here's an illustration of all the conductivity structures and their location. All of these except 2 and 7 have the capability to trigger a heart beat, but in normal conditions 1 is the true pacemaker:

So here's what seems to have happened to me:

Because of my increased exercise load, my heart did some cardiac remodeling to adapt to the increased demand. The left atrium increased in volume (confirmed by the ultrasound), which compressed the cells of structure 5 (the bundle branches). This compression led to slightly slower conduction velocity, which means that structure 6 was receiving the electrical activity a bit later than normal. And when this delay happened to be a bit too late, it thinks that the heart beat didn't happen and spontaneously triggers its own beat. This is the PVC deflection shown in my original EKG. When this structure triggers its premature beat, there would be almost no blood in the heart (because a regular beat would have just happened a few milliseconds earlier). But since this generates new electrical activity, all the other pacemaking structures reset their timers, and that's how I end up with a skipped heart beat. Then the beat that comes after the skipped beat finds the heart with significantly more blood than usual, which causes the pounding sensation that was making it hard for me to sleep at night.

Basically, in terms of the CAP theorm, my heart experienced a partitioning problem. One part of the heart wasn't aware of the real state of the system. But the heart is designed for max availability over consistency, so when in doubt, it triggers a beat. For a full cardiac arrest to happen, all 5 pacemakers or conduction pathways need to fail. The heart is an AP system (highly available and partition loss tolerant, over perfect consistency). Pretty remarkable.

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Giampaolo Mancini @mancho_z

almost 3 years ago

@Rainmaker1973 Tieni duro! In bocca al lupo!

Who to follow

Riccardo Magliocchetti @[email protected]

@rmistaken

Pythonista, free software developer, consultant. @[email protected] on mastodon

Dave Fuschi

@novelune

From a mess to the masses

Puria 💣 Nafisi Azizi

@pna

Resident hacker in @dyneorg 🌋. Doing #techno-politics 🏛. Living in Milan 🤌🏼 lately got a crush on 🔠 Typography Founder of @ForkbombEU and CTO of @agora_dem

mancho_z retweeted

Paul Stoffregen @PaulStoffregen

almost 3 years ago

We're selling the very last Teensy 3.2 boards today, limit 4 per person. https://t.co/0hd9GaUU3J If you ever made a project with Teensy 3.2 and need a few spares, now's the last chance. Will be discontinued when stock runs out.

PaulStoffregen's tweet photo. We're selling the very last Teensy 3.2 boards today, limit 4 per person.

https://t.co/0hd9GaUU3J

If you ever made a project with Teensy 3.2 and need a few spares, now's the last chance. Will be discontinued when stock runs out. https://t.co/nO56y9s4PC

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mancho_z retweeted

Web Design Museum

@WebDesignMuseum

almost 3 years ago

Happy 23rd Birthday a book Don't Make Me Think! On October 13, 2000, Steve Krug, a UX designer and information architect, published Don’t Make Me Think. The book deals with web usability and the interdisciplinary field of HCI. https://t.co/xBlROBfIpk

WebDesignMuseum's tweet photo. Happy 23rd Birthday a book Don't Make Me Think!

On October 13, 2000, Steve Krug, a UX designer and information architect, published Don’t Make Me Think. The book deals with web usability and the interdisciplinary field of HCI.

https://t.co/xBlROBfIpk https://t.co/VVXCywwjff

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mancho_z retweeted

Loopop Music @loopopmusic

almost 3 years ago

I’m curious how copying a successful, in-production product and selling it at the exact same price is a “not for profit” or “empowering the ones who have not”, as opposed to, say, simply making a profit off someone else’s investment in product design (source: Sweetwater Oct 2)

loopopmusic's tweet photo. I’m curious how copying a successful, in-production product and selling it at the exact same price is a “not for profit” or “empowering the ones who have not”, as opposed to, say, simply making a profit off someone else’s investment in product design (source: Sweetwater Oct 2) https://t.co/0sAo44qbNA

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mancho_z retweeted

Jason Fried

@jasonfried

about 3 years ago

Best way to get better and go faster is to work from the real thing. Not mockups, not wireframes, not sketches, not descriptions... Build, use, repair, refine. Real reveals what fake obscures. Get real, move faster, build better.

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mancho_z retweeted

Regione Piemonte @regionepiemonte

about 3 years ago

Ti ricordiamo che giovedì 14/9, alle ore 12, sui telefoni cellulari di tutto il #Piemonte ci sarà il test di @italertgov e comparirà questo messaggio “AVVISI DI EMERGENZA. IT-Alert. Questo è un MESSAGGIO DI TEST del sistema di allarme italiano" ➡️ https://t.co/pHUxwaZPIP

regionepiemonte's tweet photo. Ti ricordiamo che giovedì 14/9, alle ore 12, sui telefoni cellulari di tutto il #Piemonte ci sarà il test di @italertgov e comparirà questo messaggio “AVVISI DI EMERGENZA. IT-Alert. Questo è un MESSAGGIO DI TEST del sistema di allarme italiano" ➡️ https://t.co/pHUxwaZPIP https://t.co/MxzTNkbz8q

11K

mancho_z retweeted

JetBrains Rider

@JetBrainsRider

about 3 years ago

The latest news: 📰 Visual Studio for Mac is retiring in one year. 👴The average age of retirement is 65. 🔥We’re offering a 65% discount on JetBrains Rider, the only truly cross-platform .NET IDE. Get your subscription now 👉 https://t.co/1Wip9dRcwZ

JetBrainsRider's tweet photo. The latest news:
📰 Visual Studio for Mac is retiring in one year.
👴The average age of retirement is 65.
🔥We’re offering a 65% discount on JetBrains Rider, the only truly cross-platform .NET IDE.
Get your subscription now 👉 https://t.co/1Wip9dRcwZ https://t.co/IOUKpadiH4

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mancho_z retweeted

Arpa Piemonte @ArpaPiemonte

about 3 years ago

Temperature elevate su tutta la regione. Livello di rischio emergenza nei comuni della Città metropolitana di Torino e livello di pericolo sulle province piemontesi per oggi e i prossimi giorni #caldo #ondatedicalore

ArpaPiemonte's tweet photo. Temperature elevate su tutta la regione. Livello di rischio emergenza nei comuni della Città metropolitana di Torino e livello di pericolo sulle province piemontesi per oggi e i prossimi giorni #caldo #ondatedicalore https://t.co/9Ru97w9ovD

mancho_z retweeted

jacob paris ▲

@jacobmparis

about 3 years ago

ESTIMATION GUIDE - get a dev to estimate - increase the number and time unit by one 10 minutes -> 11 hours 3 hours -> 4 days 1 week -> 2 months

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mancho_z retweeted

Massimo

@Rainmaker1973

about 3 years ago

How old were you when you first noticed the "8" in the middle of the 8 of diamonds card?

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mancho_z retweeted

HAINBACH @Hainbach101

about 3 years ago

Bob Moog's Italian #Synthesizer, the Crumar Spirit is back! My friends of the Museo Del Synth Marchigiano together with Crumar reverse-engineered this rare instrument. I got to play with it in Italy and later in my studio in Berlin. Link to full video below

mancho_z retweeted

vsh🛡️⚔️ @vshymanskyy

about 3 years ago

If you (like me) are trying to use ESP32 on the @Arduino #UnoR4WiFi for your own sketches, you’ll soon learn that by re-programming the #ESP32 the board loses several powerful features. Fear not, this project lets you reclaim your power! 📎 https://t.co/IpIoHYBfkp

vshymanskyy's tweet photo. If you (like me) are trying to use ESP32 on the @Arduino #UnoR4WiFi for your own sketches, you’ll soon learn that by re-programming the #ESP32 the board loses several powerful features.

Fear not, this project lets you reclaim your power!

📎 https://t.co/IpIoHYBfkp https://t.co/vN1VacPWth

10K

mancho_z retweeted

Joshua Zimmerman @TheJewberwocky

almost 10 years ago

Presented without comment. @stahnma #devopsdays

Giampaolo Mancini @mancho_z

over 3 years ago

@xsgames_ Oh my goodness you guys have been doing good things lately with all of us doing it all in all

mancho_z retweeted

Tiny Bull Studios

@TinyBullStudios

over 3 years ago

It's #ScreenshotSaturday! Show us your #indiegame! 💬 REPLY |🔁RETWEET |❤️LIKE Showing you a new investigative feature. Can you find all the clues? Omen Exitio: 1927 coming in 2023. Wishlist now!⏬ https://t.co/qdT0zIdy6Z #gamedev #indiedev #gamebook #Lovecraft

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mancho_z retweeted

Ableton

@Ableton

over 3 years ago

Sequence MIDI intuitively on iOS, control and record your favorite AUv3 plugins, send sequences to your synths, Live and more with SAND by Matteo Caldari. See more Link-enabled apps: https://t.co/ZCNti85rJl

Ableton's tweet photo. Sequence MIDI intuitively on iOS, control and record your favorite AUv3 plugins, send sequences to your synths, Live and more with SAND by Matteo Caldari. See more Link-enabled apps: https://t.co/ZCNti85rJl https://t.co/SrA5uYRivc

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mancho_z retweeted

Nikolozi

@Nikolozi

over 3 years ago

Some limitations https://t.co/uMMP5x3oQU

565

Giampaolo Mancini

@mancho_z

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