bodmas blog

The MathsWorks Project has a series of laboratory projects on different aspects of Maths in Biotechnology. One of the projects is about blood spatter pattern analysis and has a very usable practical using milk to calibrate the relationship between drop stain shape and angle of surface.

There is also a good treatment of the mathematical assumptions made when you estimate the angle of the blood drop trajectory from the shape of the stain.

• Abstract page
• Download a PDF file of 25 pages (120Kb)

The practical I am thinking of using to allow students to practice their error analysis and to use some trigonometry in a ‘real’ context is based on dropping mock blood drops onto an inclined surface and analysing the ratio of the elliptical drop shapes to the angle of the surface. Suggestions for mock blood so far include…

• Milk with treacle or Golden Syrup added at the rate of two table spoons full of syrup to 1 mug of milk – the milk needs warming while the treacle is dissolved
• Cold Heinz Tomato soup

The Genetics Laboratory Manual from the University of South Florida has plenty of detail on Drosophilia Melanogaster and the various genetic manipulations available.

You can simulate the Mendelian inheritance of a simple trait using a couple of coins and some patience – and a Chi-Squared statistic can be calculated from a table of observed and expected frequencies.

Handy for the final content section on a Forensic Science Unit 6 assignment.

These are mostly first year University level but the datasets, examples and general approaches might be useful for Unit 6 on the BTEC Applied Sciences

• Darren Wilkinson is making his Statistics teaching notes, PowerPoint slides and homework exercises freely downloadable as PDFs
• John Matthews distributes his Biomedical Science Statistics module notes as PDFs

Professor Matthews’ Summary Measures and the Normal Distribution is an extremely clear starting point for students who are confident with numeracy and not afraid to read what is actually written.

Filippo Brunelleschi was the mathematician and artist who designed the dome of S. Maria Novella in Florence. How much maths did Brunelleschi know? Did he know about astronomy, and could he use an Astrolabe ?

I was able to find a paper mapping his friendships with local mathematicians and astronomers and astrolabe dealers using the new Google Scholar search engine that indexes academic reference material. Using Google Scholar can be frustrating as the search engine indexes cloaked content – content you have to pay to index. But at least you can find the publication details of likely articles.

Is the Lycos Fightback a distributed denial of service attack or not?

Either way, it looks like Lycos have suspended their attempt to hassle the spammers for now, perhaps for fear of retaliation against users.

The idea went as follows

• Spammers send these daft e-mails to encourage you to visit their idiotic Web sites selling enhancement products you are not interested in
• Lycos customers could download some screensaver software that would use spare time to upload data to the offending Web sites
• Lycos carefully monitored loading to keep the capacity under 95% so they were not doing a direct denial of service attack on the sites

Problems resulted from the different legislation in various countries. Denial of service attacks are being made an offence in a number of countries including the UK if the All Party Internet Group’s recommendations are put into practice. Lycos may fall foul of any legislation that is already on the books.

I’ve been using a simple robust Web based forum with a number of students studying an ICT module on an Applied Science course – students include 16-19, mature full time and mature evening class students. Teaching is primarily face-to-face but with online follow up.

I used the Gossamer Threads forum as it is free to non-profit organisations, offers the choice of threaded or linear display of responses to topics, easy to use, relatively secure, and not amazingly popular (less hacking). Gossamer Threads forum uses PERL and MySQL, an unusual combination but it seems to work fine on basic commercial Web space. The forum also offers ‘private messaging’ and attachment upload.

At present, I have found…

• Students are happy to use forum topics as link repositories
• ‘Set Piece’ discussions work reasonably well with a summarisation task to follow up
• Social malarkey helps me get to know students and students to form groups with each other
• On one forum, I prevented anyone except the moderator from starting new discussions – that forum is focussed but with less interaction
• Forums where participants can start new topics proved more involving but harder to follow and less ‘on task’
• Some students find being able to pass me Word files as attachments by ‘private message’ very useful – as well as being able to store work online (one student has a laptop with no floppy disk but with an Internet connection – she uses private messaging on the forum as upload space)
• The next phase is to get students to work in small groups in the forum to research a topic
• Main performance indicator is posts out of lesson time – ie will people use the forum to support work between lessons?

Brian Harvey has a nice simple home page. He gives out a free book on programming in LOGO - Computer Science Logo Style based on his work in releasing the open source Berkley Logo interpreter. Berkley Logo was started as a student project.

Brian is also quite rare among north americans in having an interest in Marxism, not to mention Chinese food and the Beatles.