General

Pull-Push and why brain prefers ketones as energy

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Ketones are the natural fuel for the brain

You’ve probably heard that brain cells need glucose and that’s why you need to eat high carb foods. Well, it’s true, but not completely correct.

If you eat standard western diet high in carbohydrates, and eat on average 6 or more times a day, indeed your body will use glucose for energy most of the time, excluding periods of overnight fasting.
It means that your brain cells almost most of the time use glucose for energy.

But if you are on a low-carb, ketogenic diets and/or doing intermittent fasting, then there are periods in a day, and in case of keto it can be throughout the day, that you brain cells will switch to using ketones for energy plus using glucose too.

If your doing prolonged fasts longer than 24 hours, say 48 hours or more or strict ketogenic diet, then brain cells will switch to using ketones as the main energy source.

Push-Pull strategy1

In his lecture prof. Stephen Cunnane described an interesting finding that brain cells consumption of glucose is independent of the level of glucose in blood. He calls this glucose pull. It means that brain will use more glucose for energy only when brain cells are more active, say you are thinking hard on a particular task, like playing chess.

It means that even if you consume a lot of sugar, energy drinks, fruits etc., it won’t help your brain metabolism, unless your brain works harder.

On the other hand, if there are ketones in your blood, then brain will try to use them as a fuel preferentially as much as possible. It means that when the level of ketones increases in the blood, brain cells will use more of them. Prof. Stephen Cunnane call this push of ketones.

Takeaway

To summarize, brain cells do need glucose, but glucose neither most efficient nor preferred brain fuel.

Cunnane SC. 2018. Ketones, omega-3 fatty acids and the Yin-Yang balance in the brain: insights from infant development and Alzheimer’s disease, and implications for human brain evolution. OCL 25(4): D409.

The use of both glucose and ketones as the brain’s two main fuels is governed by five principles: First, two distinctly different strategies regulate the use of glucose and ketones by the brain, a concept we call ’Push-Pull’ (Cunnane et al., 2016a, b). Brain glucose uptake is controlled by brain cell activity. Glucose is transported into the brain via glucose transporters in response to brain cell activation (Pull), so it is largely independent of blood glucose concentration. In contrast, ketones are transported into the brain via monocarboxylic acid transporters directly in response to plasma ketone concentration (Push), not brain activity. Hence, when ketones rise in the blood, they are immediately transported into the brain, an effect not seen with glucose.

  1. Cunnane SC, Courchesne-Loyer A, Vandenberghe C, St-Pierre V, Fortier M, Hennebelle M, Croteau E, Bocti C, Fulop T and Castellano C-A (2016) Can Ketones Help Rescue Brain Fuel Supply in Later Life? Implications for Cognitive Health during Aging and the Treatment of Alzheimer’s Disease. Front. Mol. Neurosci. 9:53. doi: 10.3389/fnmol.2016.00053 ↩︎

The path to meditation

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I’ve long being intrigued by meditation, but I never tried it myself. I’ve heard it was useful to calm you down. It was said it provided some health benefits etc. What caused me at last to change my mind about it was the talk that Lex Fridman had with the historian Yuval Noah Harari in which Yuval mentioned that he meditated for two hours a day and had a one month long meditation retreat once a year.

One additional motivating factor for me was that I, as I think most of the people on Earth, can’t get no satisfaction as The Rolling Stones famously sang. And indeed it’s the case, if you think carefully about it. In this information age we are bombarded with lots of things that cause us to want to buy that thing or the other. Subscribe to that service, like Netflix or the other etc. It seems like a never ending story of addiction that gets worse from day to day. Then, what can be a way out of it you may ask? Well, one of them, apparently, is meditation.

It turns out that thinking about meditation as a tool to relax and get calm is not exactly what meditation is meant for. Though, it definitely can make you calm it’s a by product of meditation, but not the main purpose of doing it.

Since Yuval mentioned meditation in that talk I googled the best books on meditation and got a list of a number of books. Among them were two books in particular that resonated with me.

The first one was 10% Happier book by former ABC News journalist Dan Harris in which he described his path to meditation and how it played out for him. I bought a used copy of that book and found it interesting and useful.

The second book in that search list was the How To Meditate book by Pema Chodron a Tibetan Buddhist nun who is a teacher at Gampo Abbey in Nova Scotia, Canada. That book was unlike the 10% Happier and it had much more profound impact on me in comparison to Dan Harris’ book. If you’ll read it and it will resonate with you, then I think you’ll understand what I mean by profound impact.

Since then, I read a number of other books that Pema Chodron wrote and each one of them is a treasure chest of wisdom and provides practical advice on how to mediate, what meditation is all about and what meditation can do for you and for all humanity if we practice it wholeheartedly.

A quality pen to stick with. OHTO GS01-S7 pen is made in Japan

If you are a person who still uses pens to take notes or write anything else on paper then you may find this post interesting. Also, do you think any pen will do or, maybe, selecting a pen is an important step to make? I think a pen that is comfortable, durable and nice is a very important thing to have.

Pens come in a number of types like ballpoint, rollerball and fountain. Also, they can be made from different materials such as plastic, aluminum and even wood. The ink that is used in pens can be water or oil based. In addition, the refill tip can have a different diameter which effects the thickness of the lines you can draw or write.

So far, I had a quite expensive Parker fountain pen and more affordable Parker ballpoint pens. I liked the most Parker ballpoint pens, since they are durable and require no maintenance in comparison to fountain pens. And I’ve used ballpoint pens for more than twenty years now.

Parker Jotter pen I had for a long time

I also like the Frixon clicker series of Pilot pens which are made in Japan and have a renowned Japanese quality. These pens allow you to erase what you’ve written and functionally they are just like pencils, except you don’t need to sharpen them.

Frixon clicker erasable pen

Recently, I’ve been looking for a new comfortable pen and a quick search brought to my attention an interesting and peculiar pen from Japan. It was OHTO GS01-S7 ballpoint pen with an aluminum body and having an oil-based black color ink. What is interesting about this pen is that its body comes in a number of colors, while the ink is always black. This pen feels nice to hold and it looks good. Functionally it resembles Parke Jotter pen, but it looks more engineered, in my opinion, and it feels more comfortable than Jotter. Maybe, it’s due to the fact the OHTO pen is longer than Jotter and has a hexagonal cross-section.

OHTO GS01-S7 with 0.7 mm refill

One unexpected feature of OHTO GS01-S7 is that you can swap its original refill with the Parker Jotter one and visa versa. I’ve found about this while watching a review of the OHTO pen by a Japanese youtuber.

Parker Jotter and OHTO GS01-S7 disassembled, side by side

I very much value quality pens, since they have this surprising capability in them. Especially, since OHTO pen only comes with black refills. So if you want to have a blue ink then you can use Parker’s original blue ink with OHTO pen! Isn’t it nice?

OHTO pen with Parker refill

Also, as I mentioned, you can put OHTO GS01-S7 0.5 or 0.7 mm refill in Parker Jotter if you fancy to. Which can be an interesting twist to do.

Parke Jotter pen with OHTO refill

All in all, OHTO GS01-S7 is a solid pen that have a nice looks and feel. It’s delivering smooth writing experience and is satisfying to click, just like a pop it toy. If you’re look for something new and creative, then this pen is for you.

Take the first step and continue doing one more step each day

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Why is that we don’t achieve the goals that we set to ourselves like losing weight, getting fit etc. Maybe, it’s because we never take the first step towards a goal in the first place. Then those of us who take that first step usually stop right after doing it. What is missing is the determination to continue to make small steps, day after day after day. As they say the road of 10,000 miles starts with the first step, but as I mentioned it’s more important to continue making step after step.

So, start small. Make a goal, say you want to lose weight. First, understand that most diets alone don’t work. Second, if you have no physical constraints start doing intermittent fasting going from long eating window to a short one. Then as you get used to fasting start incorporating walking into your fasting routine. Walking in a fasted state helps to lose more weight and also makes you feel good.

Write down your goal on a paper or digitally. Each day document the small step your took that day, summarize your progress. You can consider sharing your goal and your progress as you make it on social media which may help you to stick to your commitment due to peer pressure.

You can consider joining a support group or starting one yourself. Having other people engaged in the same activity, seeing their progress and how they overcome difficulties along the way could motivate you and provide you with a desire to persevere and move forward towards your goal.

In short, try to do something each day that moves you towards your goal just a little bit. Remember, that doing nothing is not going to help you in any way. But incremental steps in the end sum up to a long way you’ve made. The way that is taking you to where you want to be. Yes, it’s not easy. Yes, it takes will power. Yes, it’s uncomfortable at times and frustrating, but there is no other way.

Below comes a quote from Contact movie that summarizes it good

This is the way it’s been done for billions of years. Small moves, Ellie. Small moves.

‘Contac’, 1997

Start small

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To be able to make a progress in anything there is a need to be able to set achievable goals. This is true also for weight loss. Setting grand goals that are hardly achievable can overwhelm you and even stop you from doing anything altogether.

That is why I suggest to set very small goals that you can reach with some effort. For example, instead of setting as a goal to be super muscular body builder, how about first starting to walk on a daily basis? Walking is free, easy to do and you do not need any special equipment for this.

Next, if you want to start with Intermittent Fasting don’t jump right into 48 hours fast, but start small with 12 hours eating window. Then decrease it gradually to 10, 8, 6, 4 hours.

If you want to include resistance training with rubber bands, dumbbells then start small by doing push ups in the morning or evening or both. Or maybe, start with one session a week at home, then two sessions a week etc. Gradual increase in a number of sessions is much easier than committing to a gym membership that costs you a lot of money.

So starting it small can take you quite far. As a teacher in a martial school used to tell us do it
Gradually, sequentially, continuously.

Do it yourself. Write your own book.

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Quite frequently, I find myself curious why there aren’t that many books that will be interesting for me to read. Books that will be captivating, informative and inspiring. If you have the same feeling from time to time, then I think I have an answer for you.

Have you ever considered writing such a book yourself? Do you think that it’s even possible? It seems to me that it’s not only possible, but actually doable. In this post I’ll describe a couple of ways it can be done.

First of all, I’ve never written a book. So you may be thinking do I even entitled to give an advice about writing a book. Well, it’s a good question. Even though I haven’t written a book yet, I have this blog from 2013 and since then written a number of posts. So I have some understanding about what amount of effort will be required to work on an actual book.

Before describing how you can write your first book I’d like to emphasize that the type of book I envision is not a fictional book. I think it’s much easier to write a technically oriented book, which will be used by readers as a kind of manual. I have three examples to give you. I was personally involved in two of the examples.

Since writing a technical book is the easiest way of writing your first book, in my opinion, that’s talk about such book types.

Back in 2011 after I graduated I started to work as a software testing engineer at HP Indigo Division company. Working with software developers I realized that I want to write code instead of testing it. To make that transition possible I started to work through programming courses at Pluralsight online learning website. Actually, I took more than two dozens of courses there. C++, C#, JavaScript, Android development there were quite a few good courses at Pluralsight. One of the authors at Pluralsight that stood out to me was John Sonmez. Thanks to his courses I was able to get some very important advices that are still useful to me until this day.

Well, why I write that much about Pluralsight and John? It’s because John Sonmez not only had the most courses at Pluralsight at the time he also had a very popular blog called Simple Programmer. There he wrote a number of blog posts a week about software programming related topics. Lo and behold John’s first book Soft Skills: The software developer’s life manual was a compilation of the blog posts he wrote for Simple Programmer. Do you see where I am heading here? That’s right. Having a blog where you write your thoughts in a form of a post can be a springboard to your own first book.

Now that I write this, I recall that actually, my first encounter with this approach to writing a book happened in 2012 when I searched for books about C++ programming and by a mere chance I came across Alex Allain’s website about C++, Cprogramming.com. This website contains a number of tutorials about C and C++ programming. But in addition to this Alex wrote a book that was based on the tutorials from the website and the book is Jumping Into C++.

There is an interesting story about that book that I can’t help but tell you. When I started to read that e-book and do all the exercises in it I noticed that there were a number of spelling mistakes and also bugs in the code. So I decided to contact Alex and notify him about the issues. Also I suggested him that I can provide him with all the errata that I find along the way. Well, thanks to this I was able to establish a working relationship with Alex and was mentioned as one of the contributors to the overall quality of the book. This is how thanks to Alex’s helpful book I started on a road of becoming a DIY technical editor.

Returning to the main topic of the post, first Alex Allain wrote a number of helpful tutorials about C and C++, later he used them to write his first book on C++ programming. John Sonmez used his blog posts from Simple Programmer to write his first book on soft skills in software development.

And now, we come to the third example, in which I was involved quite a lot. This example, you guessed, follows the same type of an approach where first you write blog posts on a technical subject before starting to write a book on that same subject.

This time we are talking about Machine Learning Mastery website. In 2016 I started to get interested in Deep Learning, which is a subset of Machine Learning. Back in 2016 a new hype cycle about Machine learning revolution started. This time, as I’ve mentioned, it was a Deep Learning flavor. While looking for a resources on the subject I came across a blog post at Machine Learning Mastery website. The main author and the owner back then was Jason Brownlee who is an expert in Machine Learning.

The first e-book I bought from Jason was Deep Learning With Python which I found very helpful and straightforward. I bought a number of other books from the same website. As with the Alex’s book on C++, Jason’s book had a number of spelling and programming mistakes that got me thinking. So as previously, I contacted Jason and provided him with a list of issues I found. Jason was happy with my suggestions and as a consequence I became one of the technical reviewers/ editors for Machine Learning Mastery books. Since then I’ve reviewed more than 10 books on the subject for MLM.

Again, John’s, Alex’s and Jason’s approach to writing first and consecutive books was to write blog posts first and then compile them into a whole blown book. Since it was a technical subject that they wrote about, the book in essence was a collection of tutorials, which was much easier to write than a fictional book. Fiction or non-fiction for that matter is much more difficult to write in comparison to a manual about programming in my opinion.

One more, thing. To be able to write a blog post not mentioning a book, there has to be a topic that is close to your heart. A topic that excites you and makes you want to share your excitement with other readers. Otherwise, I hardly doubt there will be any good in attempting to write anything at all. I can tell it by looking at the most read posts at this blog. The most viewed posts were the ones that I cared a lot, the ones in which I shared useful and helpful information, the ones that described things I was personally involved in.

Now, the main question is shall you write a book?

Also, should I write a book myself?

Take care.

The Root Cause: In Search Of A Core Explanation

 

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© Andrey Cheremskoy, 2022-07-30

What did cause this?

Not once when faced with a problem we tend to come to a superficial conclusions that may be far away from the underling causes of the issue. This can be seen in almost any human endeavor, particularly in scientific research, in engineering, such as software programming or electronics, in medicine etc. Hence, comes the need for finding a root cause of the problem which allows to come up with a core explanation of the phenomenon at play.

There are a number of ways to uncover a root cause of the problem, for example there is a Root Cause Analysis (RCA) techniques that provide heuristics of how to search for a possible root cause or causes of the issue at hand. Ishikawa diagrams also known as fishbone diagrams is one such example of using root cause analysis that is used to uncover potential causes of certain events and it is used in industry for quality control.

Some examples

As it was mentioned root cause analysis is very useful in engineering, such as hardware development and software programming. In these fields it’s rarely the case that a systems that was implemented works for the first time it is used. Probably, you’ve heard about the phrase Smoke Testing, which is used in IT world, but it comes from electrical engineering. And it is not a coincidence that it mentions smoke, since it’s almost always the case that a system will behave in an erratic manner when used for the first time.

For example, software programmers are known to use Debugging Tools in search for defects in software, which are informally known as bugs. And Quality Control engineers, or software testers find and report these bugs as a way of living. The same is true about hardware, where even a small part, such as resistor that goes awry can cause a whole module to fail in unexpected manner.

When root cause can be misleading?

It is then reasonable to ask whether the existing root cause is the only one possible to explain the issue? This is a good question. It happens that sometimes due to an existing status quo among experts we may tend to think that the root cause is known very well and there is no need to look for it any longer. This is a dangerous situation and it happened a lot throughout human history when experts insisted that there is no other root cause and hence there is no need to search for one.

For example, physicists in the end of 19th century believed that there is nothing new left to discover in physics and what’s left are small unresolved phenomena, but then came the mystery of the black body radiation which was a door into quantum mechanics physics of 20th century.

Another example is from medicine. It was long accepted that the root causes of obesity were the larger number of consumed calories over expanded ones and a lack of exercises, while we now know that a true root cause was a high level of insulin hormone, which was caused by frequent meals and high consumption of processed food, particularly sugar.

Conclusion

In summary, it is important not only to strive to find the root cause of an issue it is also important to check whether an existing explanation of the phenomenon is the one that explains all available evidence in the best possible way.

Useful tools for video and audio editing

If you have your own YouTube channel or just make video or audio recordings using your mobile phone, it is good to know that there are editing tools that can help you remove undesired artifacts from recordings. For example, in an audio recording you’d probably want to remove or at least reduce a background noise. In a low resolution video you’d possibly want to have a better picture quality by making resolution higher if possible. Also, when you find a YouTube video that you think could have a better audio or video quality and this video has a Creative Commons Attribution license then you could download it, edit and upload again to YouTube. This post is exactly about such editing tools, or at least tools that I use myself and find very helpful. Most of them are free open-source tools except for video editing software.

Audio editing

Suppose, you have voice recordings that have a background noise. It would be nice to reduce it as much as possible without affecting the overall quality of the recording. There is a free tool that can do this and much more. It is called Audacity. Audacity is free and open-source professional grade digital audio editor and recording application software, available for Windows, macOS, Linux, and other Unix-like operating systems. I personally, use it to record myself playing drums. For this purpose I use two microphones and a two channel Behringer sound interface. After the recording was done I use Audacity to compress the recording and export it as mp3 file. But one of the features that is relevant to this post is the Noise Reduction functionality.

Real Life Example – Removing humming noise from Hamming’s lecture

For example, I used the Noise Reduction functionality in Audacity to remove background humming noise from the Dr. Richard Hamming’s 1990 lecture at NPS SGL. 

To do this I

Video editing – Super-resolution

Sometime videos can have a very low resolution, especially when they were recorded with old recording hardware, like old fashioned video cameras etc. But there is a solution to this problem which is called technically a super-resolution or upscaling. It allows to improve the resolution of the video by smoothing the pixels based on surrounding pixels. There are a number of implementations for an upscaling algorithms. Some of them like video2x upscaling software uses Deep Learning based upscaling implementation, for instance, NCNN implementation of waifu2x converter. Check out the GitHub repository of the video2x to learn how to use it.

Real Life Example – Upscaling Alexander Stepanov’s talk

For example, I used the video2x upscaling software based on Deep Learning model to upscale Alexander Stepanov: STL and Its Design Principles lecture from 320×200 to 640×400 resolution.

To do this I

  • Downloaded the original video (Creative Commons Attribution license (reuse allowed)
  • Used Audacity to add right mono channel to the original audio track which had only left mono channel available.
  • Used video2x software ran on a PC with Nvidia GPU to upscale the video from 320×200 to 640×400 resolution. Which took about 14 hours to process on that PC)
  • Used Movavi Video Editor to combine fixed audio track with the upscaled video
  • Uploaded upscaled video to YouTube.

You can try to play with the waifu2x Deep Learning powered upscaling website by uploading low resolution images and seeing the result by yourself.

Video editing

There are a number of free video editing tools out there, but from what I’ve seen the most useful ones that provide you with all required editing functionality are paid. And there is no workaround it. So I found this relatively inexpensive Movavi Video Editor software that I bought and use for all my video editing. Since I use mostly basic video editing, this tool suits me good. But if you are looking for more advanced capabilities, than you should check other versions of Movavi products or a different editor altogether.

How to download YouTube video for editing

If the YoutTube video has a Creative Commons Attribution license (reuse allowed) license you can use the video and edit it. There are non criminal ways to download such videos from YouTube.

Reading hundreds of books makes you a different person

This post is a summary of the hard copies of the books I read and recommend to read if you have similar interest as I do.

Exceptionally good books about Apollo Lunar Program

  1. Flight – Chris Kraft
  2. Left Brains for the Right Stuff – Hugh Blair-Smith
  3. Sunburst and Luminary – Don Eylse
  4. Apollo 8 – Jeffery Kluger
  5. Apollo 13 – Jim Lovell and Jeffery Kluger
  6. and much more here

Exceptionally good books about Deep Space Exploration

  1. Interstellar Age – Jim Bell
  2. Chasing New Horizons – Alan Stern and David Grinspoon
  3. Mars Rover Curiosity – Rob Manning
  4. The Right Kind of Crazy – Adam Steltzner
  5. and much more here

Exceptionally good books about Aviation

  1. Skunk Works – Ben R. Rich
  2. Have Blue and the F-117: Evolution of the “Stealth Fighter” – Albertt C. Piccirillo and David C. Aronstein
  3. The Power To Fly – Brian H. Rowe
  4. Herman The German – Gerhard Neumann
  5. and much more here

  1. The beginning of Infinity – David Deutsch
  2. The Music of the Primes – Marcus du Sautoy
  3. Prime Obsession – John Derbyshire
  4. Unknown Quantity – John Derbyshire
  5. Infinite Powers – Steven Strogatz
  6. The Joy of x – Steven Strogatz
  7. and much here and here and here

Exceptionally good books about Neuroscience

  1. Mind and The Cosmic Order – Charles Pinter
  2. On Intelligence – Jeff Hawkins

The Book Struggle Within

This is a story of struggle, love and hate, but it’s not a movie. Instead, it’s a post about my love-hate relationship with digital versus print books. I think readers who like reading both print and e-books could understand what I am talking about. There is a constant tension, even a fight, between each book type and the pros and cons they have. I personally tend to read print books, though when it’s dark and there is no good lighting available there is nothing like reading an e-book.

Well, that’s the main point, these two kinds of books are not contradictory, but could be viewed as a complementary solutions. Each type has its advantages and disadvantages, but when combining advantages of both print and e-books we got the best out of all worlds.

Print books advantages as I see them

As biological agents living in a physical world we tend to like things that we can touch, hold and feel. So it’s not a big surprise that physical print books are so appealing to us. The book having a good and colorful cover draws attention and has a seductive forces to it. You can take it, flip through it quickly. Check whether are there any good diagrams, or pictures. Jump to the end of the book to check how it ends. In addition, the books have a smell to them and their weight provides a reassurance that knowledge could be a real force in the world.

  • I value the most the flipping part and fast navigation through the print books.

Well what are the disadvantages?

Print books, being physical objects take a lot of space, which could be an issue and storing them requires a book shelf or shelves. If you happen to travel or simply wants to take a few books with you to read on the go, then you’d better be in a good physical shape and have a big suitcase, which is kind of problematic to say the least (I mean the suitcase).

Also, print books are usually cost more then their digital counterparts, so buying them isn’t cheap. But both digital and print books could be rented or borrowed in the library making them less expensive as a product.

With a print book you need a good lighting, good weather conditions, preferably without pouring rain, when you outside, and a table with a chair. Non of this is required for digital books, for example, when reading on a mobile phone.

E-books advantages as I see them

E-books are cost effective, take almost no physical space, except for the container where they reside as bytes in memory. Nowadays, they can be read on a dedicated devices, computers, mobile phones. The e-books themselves could be stored locally or read in the cloud. There are a number of good mobile phone applications and dedicated websites that provide a reader with conveniences of reading, searching, translating and highlighting the content of the digital books. When the time comes to move around, you can carry almost unlimited number of e-books, limited by the memory space you have on you device (or a remote server). All in all, the e-books sound like a clear winner in the print versus digital books fight.

  • I value the most reading in the dark, searching and translating capabilities.

But…

E-books disadvantages

Though, e-books could be read in complete darkness, it points out that the device that they are stored in requires electricity, hence a battery that should be charged. When the battery is empty good bye. Nowadays, reading a digital book requires downloading it from a cloud storage locally, which means there is a need in an internet connection, which too could be interrupted. In addition, since digital books are presented in strictly two dimensional format it is impossible to flip through them like could be done with a print book, and jumping back and forth quickly is also hardly possible, if at all. But searching them for a particular word or phrase, or translating content is a charm in comparison to print counterparts (strictly speaking it’s an advantage, ops). In addition, when you try reading and working with the content from a number of books in parallel (which happens to me) all you need is a regular table. To achieve the same feat with an e-book you need a big size monitor, and I mean really big.

Conclusion

Unless there will be invented a hybrid of a print and e-book, that would require almost no electricity (or would have a long lasting battery) and could be flipped in 3D space (say like a hologram), we are destined to use both approaches depending on circumstances where the reading process should take place.

  • One side note I forgot to mention, we have physical books (scrolls) that survived for thousands of years, but our electronic devices that store e-books definitely would not.