Weekly readings – 6th June 2020

June 6, 2020June 6, 2020by MQDuongLeave a Comment

A study published by Harvard University 20 years ago on why the US doesn’t like state welfare

What if our cities were just lit by stars

How Many People Did it Take to Build the Great Pyramid?

Amazon is the fourth‑largest US delivery service and growing fast

Physical distancing, face masks, and eye protection to prevent person-to-person transmission of SARS-CoV-2 and COVID-19: a systematic review and meta-analysis

Community and the Crime Decline: The Causal Effect of Local Nonprofits on Violent Crime

Our analysis finds that each additional use of force policy was associated with a 15% reduction in killings for the average police department. Since the average police department had already implemented three of these policies, implementing all eight use of force restrictions would be associated with a 54% reduction in killings for the average police department. Even after taking into account the number of arrests made, assaults on officers, and community demographics, police departments with all eight of these use of force policies implemented would kill 72% fewer people than departments that have none of these policies in place
Source: Campaign Zero

As for policy, our results suggest that implementing the EO to recall military equipment should result in less violent behavior and subsequently, fewer killings by LEAs. Taken together with work that shows militarization actually leads to more violence against police (Carriere, 2016; Wickes, 2015), the present study suggests demilitarization may secure overall community safety.
Source: Sage Journals

An interesting profile on the richest man in India and Asia

This 83 year old woman holds a sign that says “Defend black voices” as the marchers walk by and cheer for her. “I’m so proud of you young people,” she says. pic.twitter.com/40OURG8Ikf
— Paige Southwick Pfleger (@PaigePfleger) June 6, 2020

Don’t Bring a Knife to a Gunfight with China

Fitful nightly sleep linked to chronic inflammation, hardened arteries

Four million parts, 30 countries: How an Airbus A380 comes together

Huawei Founder Ren Zhengfei Takes Off the Gloves in Fight Against U.S.

life, Personal Growth, Random

A podcast on the importance of sleep

April 4, 2019by MQDuongLeave a Comment

I wrote about the book: Why We Sleep before. If you are interested in the subject, yet don’t find the time or the motivation to dive into the pages, you can get the gist of the book at the podcast series here. If you care about your health and brain, I urge you to have a listen.

One of the things I would like to call out here is the unhealthy practice of boasting how little sleep one has in public. Some folks tend to take their deprivation of sleep as a badge of honor. I used to be the same. There was a time before I graduated when I lived on coffee and sweet, to keep myself awake. And I talked about that to my friends with a little bit of pride. However, I learned that it was stupid of me. I was killing my brain and myself. The author is right in calling BS on the “sleep is for the weak. You can have all the sleep after you die” notion.

One of my goals in 2019 is to form the habit of sleeping 7-8 hours a night. Admittedly, I have failed spectacularly so far in the year. There is a lot of work to do…

life, Random

Mattress Shopping

January 19, 2019January 19, 2019by MQDuongLeave a Comment

I have been using an air mattress for 2.5 years since I came to the US. It was a gift from two close friends who came here before me. It has done the job and been pretty convenient, especially when it came to moving. I have moved for a total of 3 times and had I had a queen-sized mattress, it would have been much trickier and more laborious.

However, I have been having trouble sleeping lately and back pain after sleep every night, something has to change. Since sleep is one of my priorities this year and moving forward, I can’t afford only 3-4 hours of sleep every night or feeling grumpy and listless the day after. So I decided to do something I hadn’t done before: mattress shopping.

Fortunately, I have a friend working as an assistant manager for a Mattress Firm store. Thanks to him, I learned quite a bit about mattresses:

There is quite a bit of science put into mattresses, pillows and bases. In short, a combination of an adjustable base, a reasonable pillow and mattress can help adjust the mattress to your sleeping body form, relieving the pressure, let’s say, from your back. The cooling effect can also aid your sleep
Unless you buy mattresses and other stuff out of the box (brand new), you are likely to have quite a considerable discount. Normally, folks can return mattresses in 120 days. When that happens, mattresses can be resold at a significant discount, even though materialistically and practically there should be no difference as the returned goods have to be checked and cleansed before any possible re-sell.
Build up your credit score. It enables a finance payment plan at zero interest. Some don’t have that option due to the lack of credit score or having a poor one

Personally, I rarely made any purchase of the size as I did today, but I figure if sleep is of high importance to me and I spend one third of my day on that mattress for some years to come, I’d better have something that I like and actually works. Same thing with almost everything in our life.

Book, Personal Growth, Science

Most important book I read in 2018

December 24, 2018December 24, 2018by MQDuong2 Comments

2018 has been a good year in terms of great books. Great reads so far this year include Sapiens, Messy Middle, The Courage to be disliked, Subscribed, to name a few. I wrote quickly about some of them on this blog. However, none is more important than Why we sleep.

Here are a few things I learned:

Sleep isn’t like money in the bank. If you over-spend this month, saving up a little more next month will make up the difference. If you lose one quality sleep one night, that ship has already sailed. There is no getting it back. Hence, the notion of staying up late on the weekdays just to make it up on the weekends is false

Without sufficient sleep, amyloid plaques (poisonous to neurons, killing the surrounding brain cells and associated with Alzheimer’s disease) build up in the brain, especially in deep-sleep-generating regions, attacking and degrading them. The loss of deep NREM sleep caused by this assault therefore lessens the ability to remove amyloid from the brain at night, resulting in greater amyloid deposition. More amyloid, less deep sleep, less deep sleep, more amyloid, and so on and so forth

At fault were the two characters, leptin and ghrelin. Inadequate sleep decreased concentrations of the satiety-signaling hormone leptin and increased levels of the hunger-instigating hormone ghrelin. It was a classic case of physiological double jeopardy: participants were being punished twice for the same offense of short sleeping: once by having the “I’m full” signal removed from their system and once by gaining the “I’m still hungry” feeling being amplified. As a result, participants just didn’t feel satisfied by food when they were short sleeping.

When given just five and a half hours of sleep opportunity, more than 70% of the pounds lost came from lean body mass – muscle, not fat. Switch to the group offered eight and a half hours’ time in bed each night and a far more desirable outcome was observed, with well over 50% of weight loss coming from fat while preserving muscle

With a genuine lack of malice, I proceed to inform them that men who report sleeping too little or having poor-quality sleep have a 29% lower sperm count than those obtaining a full and restful night of sleep, and the sperm themselves have more deformities.
Routinely sleeping less than 6 hours a nigh results in a 20% drop in follicular-releasing hormone in women – a critical female reproductive element that peaks just prior to ovulation and is necessary for conception.

One such foreign entity that natural killer cells will target are malignant (cancerous) tumor cells. Natural killer cells will effectively punch a hole in the outer space of these cancerous cells and inject a protein that can destroy the malignancy.
Examining a healthy young men, Irwin demonstrated that a single night of four hours of sleep – such as going to bed at 3AM and waking up at 7AM – swept away 70% of the natural killer cells circulating in the immune system, relative to a full 8-hour night of sleep.
A large European study of almost 25,000 individuals demonstrated that sleeping 6 hours or less was associated with a 40% increased risk of developing cancer.

A chemical called melatonin helps regulate the timing of when sleep occurs. It governs when the race (sleep) begins, but does not participate in it. Our distractions by modern technology and LED lights suppress and delay the rise of melatonin, meaning that our body is told that sleep should start late. Throw in the enforced awakening by virtue of the industrial culture (alarm clock) and we have a recipe for inadequate sleep.

Memories remain perilously vulnerable to any disruption of sleep (including that from alcohol) even up to three nights of learning, despite two full nights of natural sleep prior.

Selectively warming the feet and hands by just a small amount (0.5 Celsius degrees) caused a local swell of blood to these regions, thereby charming heat out of the body’s core, where it had been trapped. The result of all this ingenuity: sleep took hold of the participants in a significantly shorter time, allowing them to fall asleep 20% faster than was usual, even though these were already young, healthy and fast-sleeping individuals

Most controversial and alarming are those highlighted by Dr Daniel Kripke, a physician at the University of California, San Diego. Kripke discovered that individuals using prescription sleep medications are significantly more likely to die and to develop cancer than those who do not

Saying that alcohol is a sedative often confuses people, as alcohol in moderate doses helps individuals liven up and become more social. How can a sedative enliven you? The answer comes down to the fact that your increased sociability is caused by sedation of one part of the brain, the prefrontal cortex, early in the timeline of alcohol’s creeping effects. As we have discussed, this frontal lobe region of the human brain helps control our impulses and restrains our behavior. Alcohol immobilizes that part of our brain first. As a result, we “loosen up”, becoming less controlled and more extroverted.
Your desire and ability to remain conscious are decreasing and you can let go of consciousness more easily. I am very deliberately avoiding the term “sleep”, however, because sedation is not sleep. Alcohol sedates you out of wakefulness, but it does not induce natural sleep.

Reflection

I have mixed feelings from reading this book. On one hand, I am glad to be enlightened by all the scientific findings on sleep. On the other, I am a bit horrified by what I have done to my body. Nonetheless, I am determined to prioritize sleep more in 2019 and beyond or at least to limit the hard done to my body.

Above are just a few of many great insights that the book offers. I am not doing the book justice, but I hope you spend some time reading this book and gifting it to friends or beloved ones. (I have no connection whatsoever with the author or the publisher. Just a big fan who wants as many to learn about the science of sleep as possible)

Science

Circadian rhythm, Melatonin, Adenosine, Caffeine and Sleep

August 23, 2018May 14, 2020by MQDuong4 Comments

This piece will be my summary of the first two chapters of a wonderful book called “Why we sleep”. I feel a mixed feeling of concern and excitement after reading these two chapters, and would like to share what I learned. The two chapters use science to describe the two primary factors influencing our sleep and the consequences of our normal behavior nowadays, including the effect of caffeine. Knowing these consequences helps a person make better decisions to improve his/her sleep and health.

I highly recommend the book to anyone who cares about sleep and his or her health. All the good findings are from the book. All the clumsy explanations and communication are mine.

Melatonin & circadian rhythm

Everyone has a 24-hour rhythm called a circadian rhythm. The internal 24-hour clock in our brain communicates the circadian rhythm to every area of the brain and part of the body. When the sun sets, our body starts to release a chemical called Melatonin. Melatonin signals to our body that “it’s getting dark, it’s getting dark” and that the time for sleep is close. As we sleep, the chemical starts to wear off. As soon as the sun rises and interacts with our eyes, our brain knows that it’s time to stop pumping Melatonin into our bloodstream. Once the chemical stops circulating, the brain and body know that it’s time to wake up. The rhythm continues in the same way every day regardless of our lifestyle.

It’s worth noting that Melatonin has little effect on why we feel sleepy. It is just a signaling chemical released by our body to trigger a certain action. In this case, it’s a) knowing that it’s dark b) getting up now.

Adenosine and the sleep process

As we are awake, our body constantly produces a chemical called Adenosine. The more Adenosine is accumulated, the sleepier we feel. It is because the concentration of Adenosine will trigger the sleep-inducing part of our brain and mute the wake-promoting region. The production of Adenosine happens only when we are awake and stops when we are sleeping.

The diagram below will explain why the urge to sleep is the biggest at 11pm or midnight. The blue line is our sleep process which represents the level of Adenosine. It rises from 7am to 11pm and decreases when we are asleep. The black line represents our circadian process. It doesn’t change because of our lifestyle. On the other hand, the blue line can certainly does

What will happen if we pull an all-nighter?

As we stay awake during the night, the level of Adenosine continues to rise. Around 4-5 am in the morning, we will feel particularly sleepy since the level of Adenosine is the highest at that moment so far (the orange line). We will feel better in the morning, especially at the peak of our circadian rhythm. However, the level of Adenosine continues to accumulate and later in the evening, we will be hit by a wave of sleepiness that is even harder to resist. To remove the extra sleep pressure from an all-nighter, we will have to sleep longer in the morning. However, who can have the luxury of sleeping till 10am in the morning during the weekdays? As a result, we become sleep-deprived to some extent. There is always a residue of Adenosine from the previous day in our body and it will keep us sleepy, unproductive and listless.

The same happens when we party, go out or binge-watch series late at night. Instead of going to bed around 10-11 pm, we stay up late till 2-3am. Our body has only 4 hours of sleep. There will be plenty of Adenosine left to be carried over to the following day. If the behavior repeats, it will accumulate and we will constantly feel lethargic and sleepy. After a while, even longer sleeps on the weekends may not be enough to remove all the lingering Adenosine. And would you want to sleep in the whole weekends when the weather is nice outside? With family obligations, will there be enough time for sleep on the weekends?

Additionally, our sleep process and circadian rhythm can help explain why we feel easier to sleep when travelling Westward than when travelling Eastward.

When we travel East, we are forced to sleep earlier (the orange line) than we normally do. On the other hand, as we travel Westward and are tied up with business or social obligations, we would tend to sleep later when we normally do (the purple line).

Caffeine

To fight back against the urge to sleep, we tend to rely on caffeine. Caffeine does make us feel more awake and less prone to falling asleep. How does it do that?

Caffeine blocks Adenosine from interacting with the receptors in our brain, an interaction that would cause sleep-inducing effects. While being blocked from caffeine, the sleep-inducing chemical will keep increasing while we are awake. On other hand, caffeine is worn off gradually by our body. Eventually, caffeine in our body will disappear and Adenosine will be free to interact with the brain’s receptors, this time in an accumulated amount.

If we drink coffee late at night to stay awake and our body doesn’t remove caffeine fast enough, we can stay up later. Once the caffeine disappears, Adenosine in an increased quantity will attack our receptors and the urge to sleep is even bigger than it normally is (the purple line)

According to the book “Why we sleep”, it takes our body on average five to seven hours to remove 50% of the caffeine consumed, meaning that if a person has a cup of coffee at 8pm, it’s like that 50% of the caffeine is still in that person’s body by 1am. Of course, each body is different in how fast it can wear the caffeine off. That’s why some people don’t seem to be much affected by caffeine while others are more prone to the chemical’s effect. Plus, the older we are, the more slowly the caffeine-removing process takes place.

As a result, keep in mind the effect of Caffeine before you decide to sip that hot and delicious cup of coffee or tea at night.

Consequences of sleep deprivation

Diminished immune system
Higher risk of cancer
Higher risk of Alzheimer
Higher exposure to diabetes
You feel hungry despite being full. Hence, you’ll be more susceptible to gaining weights

References

H. Keong. (2015). Vulnerability to Sleep Deprivation: A Drift Diffusion Model Perspective.

M. Walker. (2017). Why We Sleep: Unlocking the Power of Sleep and Dreams