G+C: Module 2

The second module is all about basic cosmological stuff. There are another 4 lectures with embedded questions running to about 25 minutes in total.

It starts with some basic definitions, then discusses homogeneity and isotropy. Then some time spent on the expanding universe, and finally a quick derivation of the Friedman equations.
The questions I'm getting more use to and managing to cover OK. A few of them I have to think a little, but so far not needed pencil and paper, but that will probably change with the questions that are up coming.

So nothing I haven't seen before, but I struggled to follow the mathematical derivation - I have done it before so if necessary I think I could follow it.

So after thinking about it, I decided to tackle the questions. There were 10 multiple choice questions based on the text, and most of them were reasonably easy to answer. A few were more tricky, and I had to review material, but actually still nothing requiring pen and paper as yet.

G+C: Module 1

So - the course starts! First thing is it seems to go at quite a rate. We're expected to go through two chapters a week, and then answer a quiz on the topic. You need 60% to pass for each quiz. You get two deadlines to complete the quiz by, with only half marks available if you slip the first dead line. So the pressure is on!

The first lecture is a 15 minute video on the history of cosmology and some background material. The video is powerpoint like slides mostly with narration over it, and occasional inset video of the speaker.

I noticed some yellow marks on the slider at the bottom of the video, and found when it got to that point the video paused and you got asked some questions. You get instant feedback on these so it's quite interactive.
However some of the questions were suddenly a little heavy for late night consumption!
Quick, integrate between limits 0 to 1 e^x dx. What quantum jump gives the H-alpha line. I admit to having to google that one - I thought it was probably 3-2 but wasn't confident when it came to it.

A couple of things I did learn from this though, which I presumed I'd learn some new things.

• Bolometric output is the whole output of something. I sort of knew that, but it's not something that concerns me normally, but something clicked here.
• He went over Olber's paradox, and said not only did it apply to light, but also to gravity. You can recast the paradox into "why aren't we ripped apart by the total tidal force of the gravitational interactions?"

So most of it was a general introduction. The spontaneous calculus was a bit of a shock - but apart from that it was ok.

The next two videos were on more general history leading up to CMB and Dark matter and things like that, taking us up to the present day. These also had quizes in them, but I found them much easier to answer!

So that's module 1 done - about 45 minutes of video in all, with some questions thrown in. Not bad for the first day :) I need to do module 2 though before attempting the assessed quiz.

Change of direction

So I finished my OU degree, and I've gone into postgraduate studies in astronomy now. I did do one last OU course, SXP288, but really only for the residential component. The way education is funded has also changed, and this means the course fees have quadrupled. I can get some transitional arrangements if I was studying for another degree, but I think I don't really have time for that, and really I would only want to pick and choose which courses I would do.

So reluctantly, I've probably come to the end of my time with the OU, through pressure of time, finance and the changing face of education.

I'm learning a lot of new stuff in my postgraduate studies, and did 6 course last year local to the university, which I'll skip over. However chatting to a friend, she mentioned the new set of courses which are free through coursera.org - and I thought, why not give them a try, So here I am, signed up for something reasonably relevant - a course on Galaxies and Cosmology. Yes - I'm staying somewhat in my comfort zone, and partly worried I won't be able to manage it which would be embarrassing. I'm also just interested in what the format will be (this one comes from CalTech!) and how it will all work.

So slightly scary, but well worth the price!

SD329: TMA-4

The final TMA.

Three questions.
The first one is the big one though, as it has 50% of the marks. We have to write an essay, of no more than 1500 words(!) on mechanoreceptors and their use in proprioception. Also it needs to include body image and body schema. I don't like essays much. This seems to have been reflected in my marks, although I think I made a fair stab at it.

Question 2 - we look at some images of rat glomeruli, when labelled with radioactive substances, and look at the uptake when exposed to three compounds. We have to comment on the similarity and differences in the compounds, the patterns shown in the glomeruli, and then bring it together by saying whats happening here with known mechanisms of odourant coding. I found this one a bit difficult to answer well. Not really sure what was being looked for outside of the obvious.

Question 3 - pain - and how Ibuprofen, codeine and amitriptyline work, where they work and what side effects they have.

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SD329: Book 4 - Touch and Pain, Smell and Taste, Integrating the senses

The last book contains the final three blocks of the course.

The first block (block 5) is about touch and pain.
It starts by looking in detail at touch and the various sense receptors used to detect touch, pressure, and so on.
Then it looks at the integrated perception of touch, and how it is perceived. This is followed by the sense of proprioception - which is how you know where your arms and legs etc are without actually looking at them.
Its an important sense, as a video of someone who lost it shows, they are unable to walk or even sit in some cases.
Finally we look at pain, how it is sensed, how its passed and what various drugs can do to stop pain.

Smell and taste are block 6, and it seems there is still a lot to learn about the exact mechanisms that work here. It starts by looking at smell and how the structure of molecules and the sense of smell don't always seem to be correlated. Then there are the usual nerve pathways to consider, and theories on how exactly smell works etc.
Taste is similar in a way but much less complex as there are only 4-5 basic tastes.
Then a quick bit on combined taste/smell.

Then finally a rather short block on the integration of the senses. Things covered include the focus of attention and connection between sight and sound, and things like motion sickness.

Phew - another course that I've read to the end of.

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SD329 - TMA3

Course work 3. Three questions.

Question 1 is the biggest. In this we have to perform a home experiment, and then write it up as a proper experimental write up. The subject is the Pulfrich effect, which is an oddity in visual processing. You view a pendulum in this case or other moving thing using both eyes, but with one eye slightly obscured by a filter making the scene less bright. The brain interprets the slight lag in a similar way to seeing things moving in 3-d, so the pendulum which is swinging back and forth in front of the subject, starts to apparently take on a elliptical path moving closer and further away at the peak swing. What's more you can measure this using a pointer stick and work out where apparently the object comes to its closest point. From all this it is possible using a bit of trig to work out what this means in the delay in neural processing.  Myself and my daughter set this up one Sunday morning as my variation on the experiment was to see if the difference in ages affected the processing speed.

I used a tin of beans attached to the curtain rail, and a handy dog as backdrop. We were supplied with

Anyway - the experiment went ok, and the write up too. 1500 words or so with references and so on.

Question 2 is a short essay for the layman, describing visual processing contrasting bottom up and top down processing. This wasn't too bad, after the marathon first question.

Question 3 was much easier for me anyway - it was about focal lengths and whether a person was short sighted or not, and what was the nearest distance they could observe etc. Some basic maths and a few definitions.

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