Superfluid Helium

A limerick:

My friend just sent me this so y'all have to suffer too

Le festival Sōma-shi 相馬市 - préfecture de  Fukushima-ken 福島県. 

La région de Sōma est réputée pour ses chevaux. Tous les ans, du 22 au 25 juillet, s'y déroule le Sōma nomaoi 相馬野馬追, littéralement : “chasse aux chevaux sauvages de Sōma” autour des sanctuaires Ōta jinja 太田神社 et Odaka jinja 小高神社 à Minamisōma-shi 南相馬市, et du sanctuaire Nakamura jinja  中村神社 à Sōma. Durant 3 jours, les anciens cavaliers samouraïs sont mis à l’honneur lors de différentes démonstrations, parades de samouraïs, courses de chevaux, reconstitutions de batailles et processions.

Entanglement Made Simple, a divulgative article of theoretical physicist and Nobel laureate Frank Wilczek, in Quanta Magazine.

Image by James O'Brien for Quanta Magazine

Ojiya chijimi summer kimono, seen on

This type of kimono is made in Niigata prefecture (old Echigo province). Hemp kimono fabric bolt (tanmono) are laid outside to be whitened by sunlight reflecting on the snow. This process is similar to the one used for yuki-tsumugi kimono, and both are registrered as UNESCO Immaterial Heritage.

This process is depicted in Kawabata’s Yukiguni (Snow country)

The chijimi creased effect is considered very chic. Snow-made fabrics are especially appreciated for summer clothings.

Word of the Day: potlatch

n. An opulent ceremonial feast (among certain North American Indian peoples of the north-west coast) at which possessions are given away or destroyed to display wealth or enhance prestige

Image: “Klallam people at Port Townsend” by James Gilchrist Swan. Public Domain via Wikimedia Commons

Computer Science/Engineering Masterpost

Online lectures:

Discrete Mathematics (x) (x) (x) (x) (x)

Data Structures (x) (x) (x) (x) (and Object Oriented Programming (x) )

Software Engineering (x)

Database (x)

Operating Systems (x) (x) (x) (x) (x) (x) (x)

Structure and Interpretation of Computer Programs (x)

Computer Architecture (x)

Programming (x) (x) (x) (x) (x) (x) (x)

Linear Algebra (x) (x) (x)

Artificial Intelligence (x) (x)

Algorithms (x)

Calculus (x) (x) (x)

Tutorials (programming) and other online resources:

Programming languages online tutorials and Computer Science/Engineering online courses

Java tutorial

Java, C, C++ tutorials

Memory Management in C

Pointers in C/C++

Algorithms

Genetic Algorithms

Websites for learning and tools:

Stack Overflow

Khan Academy

Mathway

Recommended books:

Computer organization and design: the hardware/software interface. David A.Patterson & John L. Hennessy.

Artificial intelligence: a modern approac. Stuart J. Russel & Peter Norvig.

Database systems: the complete book. Hector Garcia-Molina, Jeffrey D. Ullman, Jennifer Widom.

Algorithms: a functional programming approach. Fethi Rabbi & Guy Lapalme.

Data Structures & Algorithms in Java: Michael T. Goodrich & Roberto Tamassia.

The C programming language: Kernighan, D. & Ritchie.

Operating System Concepts: Avi Silberschatz, Peter Baer Galvin, Greg Gagne.

Study Tips:

How to Study

Exam Tips for Computer Science

Top 10 Tips For Computer Science Students

Study Skills: Ace Your Computing Science Courses

How to study for Computer Science exams

How to be a successful Computer Science student

Writing in Sciences, Mathematics and Engineering:

Writing a Technical Report

Writing in the Sciences (Stanford online course)

Writing in Mathematics, Statistics and Computer Science Courses 

The Blood Of Dragons Could Destroy Antibiotic Resistance

Antibiotic resistance is one of the most pressing problems of our times. Traditional antimicrobial drugs aren’t working the way they used to, and the rise

Antibiotic resistance is one of the most pressing problems of our times. Traditional antimicrobial drugs aren’t working the way they used to, and the rise of “superbugs” could bring about the post-antibiotic age, where easily treatable infections suddenly become life-threatening incurable illnesses.

There have been a slew of new discoveries recently that have revealed brand new ways to turn the tide, but the latest revelation at the hands of a team from George Mason University is a particularly unusual sounding one. As it turns out, we could use the blood of dragons to annihilate superbugs.

No, this isn’t an analogy or a plot line from Game of Thrones. The devil-toothed Komodo dragon – the devious beast from Indonesia – has a particular suite of chemical compounds in its blood that’s pure anathema to a wide range of bacteria.

They’re known as CAMPs – cationic antimicrobial peptides – and although plenty of living creatures (including humans) have versions of these, Komodo dragons have 48, with 47 of them being powerfully antimicrobial. The team managed to cleverly isolate these CAMPs in a laboratory by using electrically-charged hydrogels – strange, aerated substances – to suck them out of the dragons’ blood samples.

Synthesizing their own versions of eight of these CAMPs, they put them up against two strains of lab-grown “superbugs,” MRSA and Pseudomona aeruginosa, to see if they had any effect. Remarkably, all eight were able to kill the latter, whereas seven of them destroyed all trace of both, doing something that plenty of conventional antibiotic drugs couldn’t.

Writing in the Journal of Proteome Research, the researchers write that these powerful CAMPs explain why Komodo dragons are able to contain such a dense, biodiverse population of incredibly dangerous bacteria in their mouths. Although it’s not clear where all these bacteria originally came from, the chemical compounds in their blood ensures that they’ll never be properly infected.

In fact, it was this ability to co-exist with such lethal bacteria that piqued the interest of the researchers in the first place.

“Komodo dragon serum has been demonstrated to have in vitro antibacterial properties,” they note. “The role that CAMPs play in the innate immunity of the Komodo dragon is potentially very informative, and the newly identified Komodo dragon CAMPs may lend themselves to the development of new antimicrobial therapeutics.”

It’ll be awhile before these CAMPs are tested in human trials, but the idea that we’re effectively using dragon’s blood, or plasma, to fight against resurgent diseases is genuinely quite thrilling. Alongside Hulk-like drugs that physically rip bacteria apart, there’s a chance that, with the help of these legendary lizards, we may win this war yet.

How Humans Change Space Itself

It’s no surprise that humans influence the surface of our planet, but our reach can go farther than that. Humans affect space, too.

We know storms from the sun can naturally change the space environment around Earth, which can have an impact on satellites and power grids.

Scientists now know that Cold War era nuclear tests in the 1950s caused similar effects.

Particles around Earth are organized into layers known as radiation belts. These 1950s tests created a temporary extra layer of radiation closer to Earth. 

The effects of this could be seen all around the world. Aurora appeared at the equator instead of the poles, utility grids in Hawaii were strained, and in some cases, satellites above test sites were affected. 

Some types of communications signals can also affect Earth’s radiation belts. 

Very low-frequency waves, or VLFs, are used for radio communications. They are often used to communicate with submarines, because these waves can penetrate deep into the ocean. 

The waves can also travel far into the space environment around Earth. When these waves are in space, they affect how high-energy particles move, creating a barrier against natural radiation.

The outer edge of this radio-wave barrier corresponds almost exactly the inner edge of Earth’s natural radiation belts – meaning it could be human activity that at least partly shapes this natural radiation around Earth.  

For more NASA sun and space research, visit www.nasa.gov/sunearth and follow us on Twitter and Facebook.

Make sure to follow us on Tumblr for your regular dose of space: http://nasa.tumblr.com

Molecule of the Day: VX

VX (C11H26NO2PS) is a colourless, odourless, oily liquid under room temperatures. It is a member of the V-series of nerve agents, and is an extremely potent poison - only 0.01 grams of it is needed to kill a person by skin contact. VX was recently implicated in the assassination of Kim Jong-nam, the half-brother of the North Korean leader Kim Jong-un, in Malaysia.

VX is a potent inhibitor of acetylcholinesterase, which breaks down the neurotransmitter acetylcholine into acetic acid and choline. The normal function of the enzyme is to regulate the concentration of acetylcholine within the synaptic cleft, so as to control the frequency of binding of acetylcholine to cholinergic receptors on the postsynaptic cell membrane and hence the transmission of impulses across the synapse.

Consequently, the inhibition of acetylcholinesterase results in a rapid increase in the synaptic concentration of acetylcholine, as the presynaptic knob continues to synthesise it and secrete it into the synaptic cleft. As a result, the cholinergic receptors on the postsynaptic cell membrane are continually stimulated, and a rapid series of action potentials are triggered. This results in muscle spasms and eventual paralysis, leading to death by asphyxiation due to paralysis of the diaphragm.

VX exposure is usually treated using an injection of atropine and pralidoxime. Atropine inhibits certain cholinergic receptors, reducing the binding of acetylcholine to receptors and thus the triggering of action potentials. On the other hand, one end of pralidoxime binds to acetylcholinesterase and the other binds to the phosphate group of VX, which causes the VX molecule to detach from the enzyme together with the pralidoxime molecule (see below). This restores the ability of acetylcholinesterase to hydrolyse acetylcholine, hence reducing its synaptic levels.

VX is synthesised from phosphorus trichloride over multiple steps; first, it is methylated, reacted with ethanol, then transesterified with N,N-diisopropylaminoethanol to produce QL. This is then oxidised with sulfur, and isomerised via heating to produce VX.