Leibniz immortalized

I saw this in the supermarket the other day. Could this be an unintended reference to the co-inventor of calculus, now inadvertently immortalized as a biscuit brand? 

Apparently, this is not an error. Leibniz biscuits are indeed named after Gottfried Leibniz by the Bahlsen confectionery company which makes them!

A full FAQ on the subject is available on the Bahlsen website. Here's some pertinent information translated straight from the german FAQ.

1) Company founder Hermann Bahlsen created "Leibniz Cakes" in 1891, naming it after one of the most famous inhabitants of Hanover, Gottfried Wilhelm Leibniz (1646-1716). To identify foods after famous people was not uncommon at that time (eg Bismarck herring, Schiller's hair, Mozart ball). 

2) Leibniz Butter Biscuits have "52 teeth" for purely aesthetic reasons. Hermann Bahlsen found that with this number, the cookies had the best appearance. Only genuine Leibniz butter biscuits have 52 teeth. If you are puzzled as to what teeth are, go count the notches on the edges of this biscuit. 

3) On the issue of teeth, other Leibniz products have a different number. "Leibniz whole grain" and "Leibniz Landkeks" have only 38 teeth. This is due to the consistency of the dough that is slightly coarser than the type used for butter biscuits. The teeth must therefore be greater in size or they would break too easily. The "Choco Leibniz" has 48 teeth, because being covered with chocolate, the underlying cookie is slightly smaller than the normal butter biscuit version. The overlaying chocolate layer does however have 52 teeth. "Leibniz Minis" have exactly half of the teeth (26) of a butter biscuit. 

4) On the issue of the animals in the "Leibniz Zoo" series, zoo packs contain 17 different animals: rhino, turtle, sheep, owl, penguin, monkey, squirrel, rabbit, duck, camel, cat, elephant, lion, bear, dog, donkey, horse. The ratio of species per pack of "Leibniz Zoo" is not always the same for technical reasons. While the animal forms are represented in equal proportion, after baking, the cookies arrive in a single mix to be filled into packs. Thus, the number of individual animal per pack will be distributed by random chance. 

5) If you would like a "zoo" scrapbook, send a stamped 55 cents A6 envelope with your address to: Bahlsen, 30001 Hannover.

A poop joke

Heard an awesome poop joke today.

Time Dilation

Ever had your day lengthened by 4.8 hours? This was a clock that D had got for me as a gift in the US. It tells the time in binary and gets its power from a step-down AC transformer. That alone should have been warning but I brought it from the US to use in my Singapore office. Check out the video for the full deal.

Here's an example of how AC frequency can utilized by ICs for timing purposes.

http://www.intersil.com/data/an/an1342.pdf

tl;dr The 60 Hz power line frequency is often used to drive timing in US clocks. Consider this before plugging a US clock into a 50 Hz system.

Beer Bubbles

This is a video of beer bubbles generated by the IPA in my previous post. The release of the bubbles is described by Henry's Law. Once the bottle is opened, the gas pressure falls and beer is no longer in equilibrium with the vapor phase. Gas bubbles start to nucleate at sites in the glass harboring microscopic crevices which have trapped pre-existing air. Bubbles that have grown sufficiently buoyant then break off and head to the surface.

Unfortunately, my video rotator program does not seem to be functioning well so it is oriented sideways.

You will notice that the bubbles seem to start slow at the bottom but gain velocity as they rise. In fact, you can demonstrate this for yourself by freezing the video at any point and measuring the length of the bubble streaks as a surrogate for velocity. I did this for 20+ bubbles on a freeze frame and plotted the following graph.

The bubbles' velocities can probably be approximated using Stoke's velocity. However, this generalization will not take into account drag forces due to surfactants and other factors. I found this paper useful for getting a general intuition for bubble velocity physics. 

Homebrew

My colleague happens to be a well-known yeast researcher and lately, he has gotten into brewing his own beer. The results of his improvised setup are outstanding. Here are two bottles which he was generous enough to share. On the left is a darker ale and on the right is an IPA. 

I took the IPA out for a spin. Here it is poured into a glass. It is as delicious as it looks.

Results for the second darker ale will be posted later.

Fire at Pulau Bukom

Pulau Bukom is an offshore island of Singapore. Shell has a major oil refinery on this island which caught fire two days ago. Here's a view of the action from the lab.

And here is Reuter's report of the incident.

http://www.reuters.com/article/2011/09/29/us-shell-refinery-fire-idUSTRE78R2B420110929?feedType=RSS&feedName=topNews&rpc=71

Copters

Singapore likes to celebrate national day (Aug 9) by flying its american aircraft during the national day parade. These flew over the city during a rehearsal for the parade. 

Chinook

Blackhawk

Apache Longbow 

The F-15s were too high to be captured by my  phonecam.

My lab, coolest place in the world to hang out.

Cat update

Kitchen cat.

Landlady, the cat who shares my working space.

Acronym fail

I guess NHWKT was not quite as catchy.

Employment Pass

The Employment Pass division of the Ministry of Labor. I took my summer student here to get his employment papers. It turned out to be a more pleasant experience than I expected. There are also booths for children to occupy themselves but the chairs were a little small for me.

Queuing in Singapore

Singaporeans will queue up for a good bargain.

Experimental controls

Saw this ad on a bus the other day at a traffic red light. Different eyes for before vs after. Epic fail for uncontrolled experiment.

Candy Mountain

I was in the promised land of candy the other day.

Poop Splash Maximizer/Minimizer Graph

I note the topical interest in minimizing poop splash and have thus included a graph of Poop Momentum vs Length of Poop. Essentially, you'd want to make L longer or shorter than 2/3D. Everything else being equal, it pays to make L longer since momentum decreases more sharply on this side of the curve. For the purposes of this graph, D = 20cm.

Optimizing poop splash

I was taking a poop this afternoon and was revisited by an old problem. You are seated on a crapper with a constant anal sphincter to water-line distance D. The greater the length (L) of poop extruded before sphincter-executed release,  the lesser the distance (D-L) for acceleration but the greater the mass of poop available for making a splash. What is the poop length L at which maximum splash is achieved?

Larger poop momentum (MV) will result in more splash. Find L for maximum MV.

D = Distance from anal sphincter to water-line
L = Length of poop column
A = Cross-sectional density of poop
M = AL = mass of poop
V = Velocity of poop hitting water

From newton's equations

V^2 = U^2 + 2A(D-L) (where U = 0 and A = 10)
V^2 = 20(D-L)
V = Sqrt[20(D-L)]

MV = AL * Sqrt[20(D-L)]

dMV/dL = -10AL*(20D-20L)^(-1/2) + A(20D-20L)^(1/2)

If dMV/dL = 0,

L = 2/3 D

Conclusion: To maximize splash, release poop two-thirds of the way to the water-line. 

Do you like lab toys. I like lab toys. Here are some that have arrived since I last posted pics. 

This is an anaerobic chamber (my foot included for scale). When in operation, the internal atmosphere will be devoid of oxygen to allow for the growth of strictly anaerobic organisms. How is that possible you ask?

A gas mixture containing 5% hydrogen is introduced into the chamber following which the device below (essentially a fan blowing vertically upwards) will pass air through an aluminium canister containing palladium. Palladium catalyzes the reaction of hydrogen with oxygen to form water vapor, thus removing oxygen within the chamber.

To keep the reaction favorable, the canisters below contain desiccant to remove water vapor from the air. You can get oxygen tensions from 20% (in the air we breathe) to 1-3% quite easily.

Nikon TS-100 microscope for tissue culture.

Rotary evaporator for organic chemistry. This device uses vacuum and heating to draw organic solvents out of a sample into the gaseous phase. A chiller circulates cold liquid through the condenser glassware at the top, causing the organic solvent to condense and collect in the large round bottom flask (bottom left). This can be emptied as needed.

This is the chiller which feeds cold liquid into the condensing glassware of the rotary evaporator.

Ultrasonic water bath. Good for cleaning jewelry. Also good for dispersing colloidal suspensions.

Large 4 degrees refrigerator. Extra awesomeness points for the brand being 'Yoda'.

PCR machine from Biorad. If you don't know what PCR is, go educate yourself here.

UV transilluminator for visualizing and cutting bands out of DNA gels for DNA purification. Not to be used as Disco Black Light!

One of our biorad gel rigs for gel electrophoresis.

Maryland 3

My favorite signage from WH's lab bench. As you can tell, he is very religious.

Maryland 2

Here are some pics of vegetation out in Finksburg, Maryland. 

The deer have had a field day with the shrubs. You can see how high they are able to reach. In time, they will become a new type of giraffe.

I planted some american ginseng (Panax quinquefolius) in the woods last fall. This may or may not be an early shoot. It is hard to tell right now. Ginseng will bear red berries later in the year. Here is a website with some information on ginseng. 

This is our planting box which fed us last year with tomatos, herbs, chillis, onions, carrots and other delicious veggies. I have left a lone brusselsprout plant which reseeded itself this year. In the rest of the space, I have seeded buckwheat and red clover as a cover crop.

Here are some dead Thistle. Thistle is not our friend and must die.

Here is a periwinkle plant (the one with the purple flowers, not the thistle beside, which must die). Periwinkle is the original source of vincristine, a microtubule destabilizing agent causing mitotic arrest that is used in cancer treatment.

A bed of red clover planted last year which seems to be taking well. Grow well young padwans. The time will soon come when you must battle the thistle army.

A stand of chives planted last year which seem to be faring well.

Our maple tree, which seems to have survived the car which crashed into it last year, ripping half the bark off. A little duct tape, some nails and voila, the tree seems to have survived the trauma. In the foreground are the characteristic samaras (winged seeds). The driver of the car did a hit and run but unwittingly left amongst his car debris, a metal tag with his VIN number on it. Epic Fail.

Maryland 1

My spot in the KV lab has already been put to good use by YQ. I hope there is method to his madness.

Here is a piece of fascia that got torn off our roof during the tornado.

WH hid a dozen of these unicorns in our house. I worry for his sanity. Here's one which I have hung up in our garage.

Just got back from the US

D and I were in the United States for the past 2 weeks. My lack of posting were for two reasons. First, our well pump in Finksburg broke down, meaning that we had no water for several days. Second, the tornado that recently passed through the area had done damage to our house. Not serious damage, but stuff that had to be fixed nonetheless. In the next few posts are belated pics from Maryland.

Centrifuge

More equipment. Here, a Sorvall Legend T+ centrifuge. Non-refrigerated and optimal for swing-bucket rotors at medium speeds.

This one is from Beckman Coulter, the Allegra X-22R, a refrigerated high-speed centrifuge. It's a shared resource but I've ordered a high speed rotor that will take it over 20,000 g's.

This is also an opportune time to cite one of my favorite xkcd episodes of all time. I am talking about this. And you are up for even more punishment, here's a video of a paint can being centrifuged in pendicular axes. It's a popular way of mixing various materials to homogeneity.

Five Guys

A colleague who just visited the US brought this back for D and I, a menu from Five Guys, our favorite weekend lunch haunt. Three things to note. (1) They have one of the world's best fries (2) They serve a mean grilled cheese sandwich with fresh toppings of choice (3) The free flow of complimentary peanuts which you heap into your cardboard bowl using a little shovel. Here's the menu taped to my door.

Captain Bulbosa

Meine Freunde, meet Captain Bulbosa. The Captain was a sneaky gift from D for my office. It is a species of Tillandsia and being an epiphyte, it does not require roots for growth. In fact, the presence of nitrogen-fixing bacteria on its leaves are important for the plant's nutrition. The thermometer shows 27 deg C, just nice for the Captain.