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Archive for the ‘September 2013’ Category

Curious curdling casein

In September 2013 on September 27, 2013 at 7:12 am

milk and lemon 25Sept

Kirsti: Last night I wanted a milky honey drink, and thought I would sneakily sneak a little bit of lemon into it too.

Having previously experienced the curdling disaster of squeezing lemon into a creamy sauce, what I’m about to describe sounds ridiculous. Somehow, I thought I could get away without curdling my milky drink with my drops of lemon.

As I dripped the lemon in and hoped for the best, in the back of my mind I knew what was going to happen. My drink – which was boiling water, milk, honey and a few drops of lemon – curdled immediately.

Surprise, surprise. Not!

The curdling happened because the heat sped up the reaction between the clusters of milk protein (called casein micelles) and the citric acid in the lemon. Instead of being repelled from each other as they normally are in fresh milk, the micelles rapidly glumped (yes, glumped!) together. Bummer.

Temperature is a fabulous catalyst – it gets chemical reactions going quicker and more efficiently.

So I decided to do a little (non-replicated) experiment, and tried again with cold water.  No lumps!

But it turns out that even cold milk eventually curdles. The casein micelles start loving one another, a little bit at a time, albeit FAR slower thanks to the temperature of the drink. Happily, the teeny tiny little curdles that eventually occur in your cold drink will probably not put you off drinking it, if you detect them at all.

But I still have a problem: in cold milk and water, the honey doesn’t dissolve….ahhh, there goes science again!

Intuition vs process

In September 2013 on September 26, 2013 at 11:19 am

blocks

Sarah: I’ve been helping my son learn how to do long division.

Being a bit of a maths lover, it’s something I enjoy to devoting time to. Plus, you know, helping my kids is nothing but pure bliss each and every day (apply highly sarcastic tone whilst reading that last phrase).

And yet I’ve come up against a bit of a dilemma.

I walked the kid through the steps that I follow when doing division, something like:

Problem: Divide 492 by 3

–> 3 goes into 4 one time, then carry the 1 into the next column

–> 3 goes into 19 six times, carry the 1 into the next column

–> 3 goes into 12 four times

Answer: 164

Good. It made sense. He told me that he got it, and did a few examples to prove his point.

In the classroom, he has been working with his teacher (a fantastic and dedicated lady) using blocks to carry out similar types of sums. The blocks consist of groupings of hundreds (a square of 10×10), tens (a column of 10) and units (individual blocks).

To create a visual image of the mathematical problem, the kids are asked to use the blocks to represent the large number to be divided in each case, and then work out how to divide them into groups. So using the example above, we would use the blocks to represent 492, and then divide the blocks into 3 groups of 164.

It makes sense, it’s visual, I like it.

But my kid is a bit inclined to be sloppy. Spending time and using fine motor skills to put teeny blocks into neat little piles is not his thing. He usually makes a mistake. This messes up the maths problem, and leads him to the wrong answer, or an inaccurate visualisation of what he’s supposed to be creating.

So this is my dilemma. I know using the blocks is valuable, and converts an ‘on paper’ maths problem into a 3D representation. But he can find his way through the division without them, and is improving with more practise. Should we insist he use the blocks? Or just let him work out his own favoured way?

I’m torn.

Bang bang! Ant competition

In September 2013 on September 25, 2013 at 11:24 am

ant competition

Kirsti: It’s with a huge amount of joy that I join Sarah in celebrating science in our everyday lives.

Similar to Sarah’s days, science is ubiquitous in mine. As a good example, this morning involved counting the species of ants in our front and back gardens and discussing hypotheses around – as far as we can see – why there are more types of ants out the back.

Yep, even 2 year olds understand the notion of,

“Maybe they don’t like each other very much in the front garden?”

He proceeded to tell me why he thinks that might be,

“Those black ones are bigger, and fast. They’ll bang bang all the other ones”.

And lo and behold he has described an old-age explanation for coexistence of organisms  – competition between species!

So from today I will start to collect and reflect on my weekly obsessive explorations for answers, observations made in haste as a mother, overheard lab conversations, imperfect photos of unknown phenomenon, and tales of marvellous processes, discoveries, applications and awe of science.

I hope you enjoy my reading posts as much as I’m going to love putting them together.

[photo thanks to www.alexanderwild.com]

Introducing Kirsti!

In September 2013 on September 24, 2013 at 2:23 pm

Kirsti termite mound

Sarah: Today I’m delighted to introduce Kirsti Abbot, who will now be a regular contributor to ScienceforLife.365. Yay!

Here’s a quick Q&A so you can get to know her a little better:

What keeps you busy? 

I am a mother of 2, a science educator and an ant ecologist currently at University of New England attempting to inspire first year biology students. Previously, I taught core science at Monash University.

What makes you tick? 

I love islands, ants, good coffee and green rooms. I’m a self-confessed biophile.

Do you have science in your life?

Yep! My love for science communication has lead me to studying ants with primary school students, printing ant T-shirts for friends and trying to improve my science storytelling. You can listen to me get excited about invertebrates every month on Creepy but Curious with Kelly Fuller on ABC regional radio.

I’m thrilled to have Kirsti on board, and can’t wait to read her contributions to the blog.

Once pregnant, always a mother

In September 2013 on September 21, 2013 at 1:54 pm

pregnancy shadow

Sarah: A New York Times article by science writer Carl Zimmer captured my imagination this morning.

In DNA Double Take, Carl presents and discusses recent evidence that our genomes (the total amounts of DNA in our bodies) are not as simple as we once thought.

One section of the piece tackles the genes in tissues of mothers:

Women can also gain genomes from their children. After a baby is born, it may leave some fetal cells behind in its mother’s body, where they can travel to different organs and be absorbed into those tissues. “It’s pretty likely that any woman who has been pregnant is a chimera*,” Dr. Randolph said.

*where a chimera in this case is a person with two different genetic profiles

Chatting with Dr Ngaire Elwood about this part of the paper on twitter this morning, we both agreed it was pretty cool that we retained a permanent record of our children in our own genomes.

And then it occurred to me that perhaps even pregnancies which don’t proceed to term are still present as a genetic ‘memory’ in women. Even though I only have 3 children now, perhaps there are elements of the fourth pregnancy I also experienced still in my body.

I love that idea.

[image thanks to zeevveez on flickr]

Bears in the wood

In September 2013 on September 17, 2013 at 2:18 pm

poohbear

Sarah: Being a science writer can be a big responsibility.

Sometimes I receive serious shout-outs for help.

Like this one from my little friend Horace, whom I first I met about 10 years ago. Horace is a horse, and lives with his mummy and daddy in Brisbane. He may or may not be stuffed with cotton.

Dear Ms Science for Life,

My ‘friend’ Pooh would like to know whether there is a biological reason why anthropomorphised bears never wear pants?  Cases in point: Pooh, Humphrey, Yogi and Paddington (see attached image of Pooh with his winter jumper on … note absence of a pant).

Regards,

Horace

This was my reply:

Dear Horace,

It would be my pleasure to explain.

Have you heard the saying ‘Do bears poop in the woods?’ Obviously the answer is ‘Yes, they do. And frequently’.

Imagine an animal with no opposable thumb or indeed fingers (case in point Pooh shown above) trying to unbutton and pull down trousers 5-6 times a day – only to have to then pull them up again after lengthy arse-wiping with leaves. It would get messy. Tres, tres messy. Better to leave pants off altogether and avoid this issue completely.

Happy to be of assistance anytime.

Yours in science,

Ms Science for Life

Don’t tell me science isn’t useful.

Phase 2 starting in 3, 2, 1…blast off

In September 2013 on September 16, 2013 at 8:45 pm

brainbreak8

OK, so I promised that ScienceforLife.365 would transition to phase 2 beyond National Science Week 2013.

First, I need to tell you about the most fabulous celebratory #BrainBreak Morning Tea I hosted to celebrate my year of daily blog posts.

A group of scientists, writers, communicators, colleagues, friends and family members joined me on August 14th to eat yummy cakes, drink tea and champagne and chew the fat about science and life. Photos from the day are shown below.

I was also delighted to receive a letter from  Tom Kenyon (SA Minister for Manufacturing, Innovation and Trade) and Grace Portolesi (SA Minister for Science and Information Economy) to mark this milestone.

The letter read as follows (reproduced with the permission of Minister Kenyon):

Dear Dr Keenihan

Congratulations on your blog Science for Life.365 which has celebrated science every day of the past year.

As the Minister for Science and Information Economy and the Minister for Manufacturing, Innovation and Trade, we both appreciate the significant contribution that South Australian scientists make to our community and our everyday lives.

In particular, we admire your year-long commitment to sharing with others how your daily life is shaped by your education in, and love of, science. We also applaud you efforts in encouraging an interest in science among the general public – particularly encouraging younger people to become fascinated by the world we live in.

As you know, the South Australian government seeks to raise the research and innovation profile of South Australia while at the same time encouraging a broader understanding within our community of the importance of science in our daily lives. We would like to recognise your efforts and your dedication to writing about science and thank you for your efforts.

Yours sincerely

Grace Portolesi and Tom Kenyon

I’m very grateful for the Ministers’ acknowledgement and everyone’s support, so thank-you.

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