forgive yourself : it’s okay if you didn’t wake up early, go for a run, or finish that assignment. you’re only human
start slow : don’t set your expectations too high when you’re just starting off
keep learning : getting to where you want to be is a process. don’t expect perfection overnight
be kind to yourself : you’ll make mistakes along the way, but don’t let that stop you
These are just amazing!
Max Alexander‘s knitted moths are incredible – I am simply blown away. LOVE! I also like the irony of using wool to knit moths – normally that combination strikes fear into the heart of every knitter/crocheter I know!
African Cherry Spot Moth
Knitted Merveille du Jour Moth
Tatargina Picta Moth
Peach Blossom Moth
Some cool engineering please !!!
When I was researching about F1 sometime ago, I stumbled upon this amazing video of the lotus team playing happy birthday on a F1 freaking engine!
The way this works is that the sheet music is taken and broken down into frequency and the milliseconds that it lasts for.
And the engine is turned on and off rapidly with different frequency tones to produce the tone i.e
OFF - f1 Hz - f1 Hz - OFF - f2 Hz - f2 Hz - f2 Hz- OFF …. (entire song)
The dynamic response of the F1 engine to changes in the throttle is what blew my mind. F1 cars are able to pull this off due to the extremely lightweight flywheel/general rotating assembly.
Now you can do the same thing with motors as well. The motors can be revved up or down based on the frequency of the input.
Here’s the imperial march played on the floppy drive and Super Mario on the stepper motor:
What you are hearing is the tones made by the motor.
Notice the slider moving faster for higher frequency
If you are into Arduino and DIY projects you can play around with the ToneMelody package and piezo-buzzer to get a similar response.
Thanks for asking. Have a great day!
In 2015, a 777-200 made the Newyork-London route in 5 hours,16 minutes where the usual journey time is ~7 hours.
The flight reached ground speeds of up to 1200 km/h (745 mph),riding a powerful jet stream of up to 322 km/h (200 mph) tailwinds and breaking the sonic barrier ( 1224 km/h (761 mph)).
The principle is analogous to those high school problems in relative velocity:
“A man rows a boat in a river. The velocity of the boat is … Find the stream velocity”
If you are headed downstream i.e in the same direction as the river stream you will reach your destination faster than if you were rowing upstream.
Similarly a tailwind is one that blows along the same direction of the aircraft increasing the net speed of the aircraft ,and headwind is one that blows in the opposite direction and slows the craft down.
So, does this mean that if you are moving at v kmph and there is a headwind of -v kmph, you would just hover? Hell yeah!
Take a look at this video:
A phenomenon known as ‘wind shear’ occurs when the wind speed changes abruptly, which can cause turbulence and rapid increase/decrease in velocity of flight.
This can be really challenging during landing since if the headwind turns tailwind, there is a possibility of the aircraft overshooting the runway due to the increased velocity.
The aviation industry takes advantage of trade winds and jet streams in order to cut time off the flight and save fuel.
Tradewinds are caused by the unequal heating of the atmosphere at different latitudes and altitudes and by the effects of the Earth’s rotation (Coriolis effect).
Trade wind pattern. Credit: Earth Wind Map
Jet streams on the other hand are this narrow current of fast moving winds in the upper troposphere flowing west to east. And riding one can definitely make your travel time shorter.
Jet streams in the northern hemisphere
As a result of jet streams, within North America the time needed to fly east across the continent can be decreased by about 30 minutes if an airplane can fly with the jet stream, or increased by more than that amount if it must fly west against it.
Pilots receive a weather briefing actively during flight. Included in the briefing is the best combination of jetstreams and other wind patterns that the pilot can take advantage of saving time and fuel.
Many airports have runways facing in different directions in order to allow the pilots to use the runway that faces the wind during take off/landing.
Have a great day!
When one searches for Fourier series animations online, these amazing gifs are what they stumble upon.
They are absolutely remarkable to look at. But what are the circles actually doing here?
Your objective is to represent a square wave by combining many sine waves. As you know, the trajectory traced by a particle moving along a circle is a sinusoid:
This kind of looks like a square wave but we can do better by adding another harmonic.
We note that the position of the particle in the two harmonics can be represented as a vector that constantly changes with time like so:
And being vector quantities, instead of representing them separately, we can add them by the rules of vector addition and represent them a single entity i.e:
Source
The trajectory traced by the resultant of these vectors gives us our waveform.
And as promised by the Fourier series, adding in more and more harmonics reduces the error in the waveform obtained.
Have a good one!
**More amazing Fourier series gifs can be found here.
some recent stuff from my sketchbook!
Kelston Boys’ High School perform a massive haka in honour of the new Maori carving on campus
Mood
Peter Rabbit Sledging
by Beatrix Potter (1894)
“Love Is” In Small Things
Some sceneries and living spaces.
I wanted to get some ideas/feelings out of head and to try out some new techniques.
Full-resolutions: 1 2 3
A for-funsies furry portrait of this cool dude with the fabulous art -> @poisondynamite / @redhotsneakers <- Go check ‘em out!!!!! >w<)/
Un chat
Golden tortoise beetle transforming from gold to red
Show
Dog carved into a tree stump.
Japanese Ice-cream Machine.
This is how far into the earth humans have dug so far.
A chemical tag added to RNA during embryonic development regulates how the early brain grows, according to research from the Perelman School of Medicine at the University of Pennsylvania. The findings were published in Cell.
(Image caption: A human forebrain organoid labeled with Green Fluorescent Protein (green), neural stem cell marker SOX2 (red) and cell nuclei marker (blue). Credit: Xuyu Qian and Guo-li Ming, Perelman School of Medicine, University of Pennsylvania)
Neuroscience professors Guo-li Ming, MD, PhD, and Hongjun Song, PhD, study the basic principles of how to make a working brain. “When this development goes awry, problems happen and may cause psychiatric disorders in people,” Song said. Ming and Song use animal models and organoids, also called mini-brains, made from human stem cells to relate their findings to conditions found in people.
In the last few years, scientists have discovered chemical modifications to messenger RNA (mRNA) across the genome at certain sites and found that these changes are dynamic, meaning that a specific chemical group is added and taken off by enzymes in a regular, patterned way. The chemical group studied in the Cell paper, m6A, is the most prevalent modification to mRNA in human cells.
“We asked: Is this another layer of regulation of gene expression?,” Ming said.
The current thinking is that a tightly controlled molecular process guides the complicated development of the brain before birth—and that the process relies on a precise sequence of genes being turned on and off. However, even subtle mistakes in this process can become amplified later. Song likens this process to a train moving onto the wrong track and ending up miles and miles from its intended destination.
The classic view of this control is that DNA codes for RNA, guiding which proteins will be made by cells. However, mRNA can be modified along the way so that it can produce proteins with many variations. A new field called epitranscriptomics was born out of this knowledge.
The Cell paper is the first study of epitranscriptomics in the embryonic mammalian brain, and the key is m6A, a marker for molecules bound for disposal within the cell. Normally, m6A-tagged mRNAs are related to such processes as cell replication and neuron differentiation, and m6A-tagging promotes their decay after they are no longer needed.
If m6A is not added on the correct time schedule to a garbage-bound molecule, the developmental train goes down the wrong tracks. Ming and Song surmise that this is because developing brain cells get stuck at an earlier stage because the m6A cues for taking out the cellular trash are misread or not read at all.
The researchers found that in a mouse model with depleted m6A, cell replication is prolonged, so that stem-cell differentiation, which normally reels out daughter cells in an orderly fashion, gets stuck. The knockout mouse develops less brain cells such as neurons and glia cells, and therefore has abnormal circuitry and a non-functioning brain.
“We used an organoid, a mini-brain, made from human induced pluripotent stem cells to relate the mouse knockout findings to humans,” Ming said. “m6A signaling also regulates neuron development in human forebrain organoids.”
Neuron development in the mini-brains that Ming has developed is similar to what happens in people, modeling fetal brain development up to the second trimester.
“We were surprised when we found that human stem cells had a greater number of m6A tags compared to mouse cells,” Ming said. “Comparing the m6A-mRNA landscapes between mouse and human embryonic brain development showed us that human-specific m6A-tagging might be related to brain-disorder risk genes.”
Many of the genes associated with genetic risk for certain conditions, such as schizophrenia and autism spectrum disorder, are only m6A-tagged in humans, not in mice, raising the possibility that dysregulation at this level of gene expression may contribute to certain human brain disorders.
In the near future, the team plans to look for m6A levels in brain tissue donated by people who had psychiatric disorders, as well as if m6A regulates development and regeneration of the nervous system after birth.
From @angelbengal: “Yes Netflix, I’m still watching 👀🍺🍟” #catsofinstagram [source: http://ift.tt/2BI4Tbs ]
From @dai0.0: “【 #もずくさんのお風呂シリーズ 】 もずくさん🐱の. あかすりサービスはじめました. 湯加減チエックに続いて. あかすりをしてくれるように. なりました(*´▽`*) 「手をこっちによこすニャ🐱❤️ あかすりするニャ🐱」” #catsofinstagram #twitterweek [source: http://ift.tt/2FpgmM0 ]
From @amaccho5160: “きなこ💓ぴょこん⁽⁽٩(๑˃̶͈̀ ᗨ ˂̶͈́)۶⁾⁾💕” #catsofinstagram [source: http://ift.tt/2pmoKGk ]
Panda tree!