"There's a festival...

... on every single weekend in Santa Barbara during the summer. Don't worry about your free time!" I thought this saying about Santa Barbara is a nice brochure advertisement, but it's true! 

Two weeks ago, there was the French Festival, last weekend you could taste any kind of wine at the Wine Festival (which is a huge deal around here!) and this weekend I visited the Greek Festival. At first, I was not sure if "Greek" meant fraternities and sororities and it's all about charity and drinking, but it's not! People danced traditional Greek dances, there was lots of food and Greek soap, glittery dresses, towels, spices etc. The festival was held in a dry park downtown, so grass and the trees look kind of Mediterranean as well ;-)

Diffusion again

Last time, I just briefly wrote about the problem we had when we calculated diffusion coefficients. We were off by a factor of four. After consulting the camera's manual it turned out, that the camera does different "binning" of pixels in the mode we use for particle tracking. "Binning" means, that two pixels become one in the final image. Thus, a 1024*1024 px*px image shrinks to a 512*512 px*px image. And if you think that 6 px represent one micrometer and you do not know about the binning, it's actually 6 px being two micrometers! As the distance goes squared into the diffusion coefficient, we got our factor of 4, yay! (But never mind the software explicitly saying that there is no binning for this camera type, haha... it's only on page 60 of a 130 page manual ;-))

So my life was pink again; I continued with another experiment where we want to observe the growing and shrinking of cell polymers (microtubules). I mixed the cocktail for the experiment and was happy to image lots of moving rods (that's how microtubules look like). But after thinking about it... diffusion could make them move in a super similar way! Damn it. Even theoretical estimations show that they could move quite a bit in 30 seconds. Fortunately, there are different dyes out there to label the dynamic part (growing and shrinking) and the static part (our seeds), so we'll hopefully understand what's actually happening.

 

Diffusion coefficients

We've got a new camera in our lab which is less light sensitive than the one we had before, so we don't have to expose the more sensitive one to light which might damage it (though we have not shown that in an experiment ;-)). The determination of the diffusion coefficient with the old, sensitive camera works great! We maybe off by 10%, but after averaging I got close to 1% to the theoretical value. 

The new camera is a bit different and less fancy, but our diffusion coefficient is off by a factor of 4 - no matter what we do! It's such a "simple" experiment and I guess it's done as a lab course for freshmen, but it doesn't seem to be that easy. I guess, the camera does some binning and the image info just hides it in a smart way...

"Queen" Concert

During July, there are free concerts in one of the public parks in Santa Barbara downtown. The one last Thursday was announced to have Queen as a theme, so I went, but I was super skeptical if anybody in the world could imitate the real Queen sound.

And, well, of course it was not exactly Freddie Mercury's guitar, but it was great entertainment and one of the band members actually looked like Mr Mercury ;-) It was not like any open air concert as it started at 6 pm and people had brought picnic blankets long before that to sit close to the stage. Thus, at the beginning of the concert, we had a potluck-picnic dinner and afterwards we listened and many people started dancing. At the ending (which was early, around 8:30 pm), they played "We are the champions" and finally everybody (any age, any race) was dancing! It was a great, very intercultural and peaceful atmosphere.

Making seeds

We want to look at dynamic microtubules which are a common biopolymer in cells. So far, our microtubules just grow, but don't shrink, but we want to have both types of dynamics in our studies. To get there, we left out the stabilizing chemical and we ended up with clumps only and no network.

After talking to experts in the field of microtubules, it turned out that seeds could be helpful. The microtubules would just start growing on them. Thus, we had to made those seeds (made of tiny stable microtubules) which took seven hours! But after lots of centrifuging and incubating, the last step involved freezing the sample tubes (the small colorful tubes at the bottom of the photo) in liquid nitrogen which is great fun:

Just slowly freezing the protein would have led to the depolymerization of the seeds, i.e. we would have lots of protein in solution, but no seeds. The liquid nitrogen freezes the seeds so quickly that there's no time to disassemble. Afterwards we store them at -80°C so that no thawing happens.

Santa Barbara Harbor

Believe it or not, I have been measuring diffusion coefficients via particle tracking for days now, and we're still off by a factor of five... I've got some ideas for the reasons and we'll figure it out, but because that's so frustrating, let's talk about something nicer :-)

Like the harbor of Santa Barbara! I haven't been there before, but it's a great view, there are many restaurants and you can walk out to the pier. About 1000 boats are in the harbor (for which you have to pay a fee) and there are some which are just kept outside near the beach (which is free). But if a storm comes, your boat is washed ashore and you don't remove it quickly, the boat is destroyed and its parts carried away. Thus, the harbor fee might be worth it ;-)

How you get a job offer

You should eat a dessert! Actually, I was just eating tacos with a friend since it was "Taco Tuesday" at a local restaurant, i.e. any taco is just 2 $ and usually two or three tacos make a nice meal. It turned out that the restaurant had some nice dessert offers, so we got a "S'mores Sundae" which is an ice cream dessert with marshmallows, cookies and chocolate (yeah, it's super unhealthy, but nice :-)).

While I was waiting for the Sundae, somebody asked me with an American accent "Kommen Sie aus Deutschland?". So we talked a bit about Germany, that he stayed there for some time as well etc.  It turned out that he was working for some company around here and they like to employ physicists. Thus, we exchanged contact details and I could do an internship etc. It sounded like a great new contact overall :-)

Still berning?!

Bernie Sanders has finally announced his support of Clinton's campaign. If that's an honest commitment, is debatable, but at least the Democrats are united now. Well, nearly, as the Bernie-spirit lives on:

I'd love to have that hat! Even though Sanders won't run for president, he's got still many supporters and  it'll be a challenge for Clinton to convince the remaining voters that they shouldn't vote for Trump because he's not part of the common political establishment.

Coming back

I just flew back to the US and of course the soccer match France-Germany was probably the most viewed on-board entertainment program. The flight was a lot better than the game though ;-)

First impression after arriving in LA.

Not much has changed around here, but I am glad the bush fire near Santa Barbara seems to be gone. The weather's nice and "in the seventies" (Fahrenheit, which is around 21-25°C). The student town, Isla Vista, is surprisingly empty as most students don't have lectures during the summer term.

Graduate students do research during that time while undergraduates might work in labs as well or just work full-time for a different employee. Lectures will start again on September and the typical German "Semesterferien" do not really exist here (it's one week between the quarters).

Lindau 1.0

The Lindau Nobel Laureate Meeting is the largest yearly gathering of Nobel Laureates in the world - thus, I assumed the conference was going to be pretty cool, but it turned out to be a lot more than "just" that. To anticipate my thoughts at the ending of this meeting: I could have stayed for at least anther week to get to know all 400 young scientist and to talk more to all the ones I met, but everybody was so tired, that it was a good time to close the conference.

When I arrived on Lindau, my seatmate wished a "happy holiday" and I didn't really know what to reply. Indeed, most people go on vacation on Lindau - which makes sense as the Alps frame the Lake Constance which is great for swimming, surfing, SUPping, sailing, ... There's also a mainland part of Lindau where my host family lives.

After an opening ceremony on Sunday, the actual conference started on Monday morning with 30-min talks from the Nobel Laureates. There was a talk about soap bubbles, the climate change, LEDs, ... it was a huge, but very interesting variety. But the breaks inbetween were at least as important as the presentations themselves! I got to know many other enthusiastic young scientists from all career levels, backgrounds and countries. It was super inspiring to exchange ideas and future plans. I even met people with similar research projects and problems!

Prof. Stefan Hell talked about his motivation for experimental physics and he mentioned that he wanted to help is parents and not become a taxi-driver ;-)
As studies show, sleep is important for learning and memorizing, as Prof. Carl Wieman found out during his research on learning and education - after winning the Nobel Prize in 2001 for the Bose-Einstein-Condensate.

How to raise your blood pressure

In my next post I'll write about Lindau, but something just happened which saved my trip to the US: I finally got my visa after a two-week-fight! Yay!

After I had submitted my documents for my visa renewal 2.5 weeks ago, I got a message from the consulate that one of the most important documents got lost. Haha. Nobody knows what really happened because I am sure I sent it off, yet, I got a new one sent to Lindau where I signed it and forwarded it to the consulate in Frankfurt.
Then they couldn't find my DHL envelope I had sent off days before. It turned out that it takes about three days until anything in their mail box gets to the correct case within the consulate. After all, I got the e-mail that they had everything to issue my visa on Thursday. 

But that doesn't mean you get the visa right away, does it? So I tried to contact them again, but today's the 4th July, so nobody's working. And I am flying this Thursday!
My mind started spinning around re-booking the trip to Friday, traveling to Frankfurt and picking up my visa and so on.

But a wonderful miracle happened and the DHL Express envelope with my new visa just arrived today. I guess I'll become Catholic ;-)

It's just over

I just came back from one of the most amazing events I ever attended. Okay, to be honest, that might be a bit over rated, but I had a great time with about 400 other young enthusiastic scientists and 30 Nobel Laureates on the beautiful Island Lindau. We discussed lots of physics, but also education in science, politics, careers inside and outside academia, and it feels like everything else. I'll write more in the next few days, but I have to catch some sleep first - that's the only reason why I would argue we had to come to an end with this amazing conference. Here are some first impressions: