Here is a fun science experiment that all kids love….. and no matter how many times a child may have done this one, they are always happy to do it again!
HOW TO MAKE SLIME
You will need….
two small bowls or cups
PVA glue (white or clear is fine)
water
food colouring (optional)
Borax* powder.
*You can pick up the borax powder in your local chemist (See note below)
What you do…
To the first bowl add half a cup of water and half a cup of PVA glue and mix well.
If you want to make coloured slime add a few drops of food colouring and mix this in well.
In the other bowl add one teaspoon of borax powder to one cup of water and mix well until all the powder is dissolved!
Now for the fun bit… pour the borax solution into the PVA/water mix and mix, mix, mix!!! YOU HAVE JUST MADE SLIME!
This experiment is as fun as it looks!
If you want to keep your slime just pop it into a Zip-lock bag and seal it and it will be ready for you next time you want some slimey fun!
So what is happening?…
Congratulation… you have just made a polymer!! In simple terms a polymer is a substance made up of lots of molecules arranged in long chains. If you imagine that the glue is like cooked spaghetti, it slides and slips around the place quite easily. When we add the borax to the glue it causes some of the molecules in the glue to stick together making the glue more rubbery and less liquid! Imagine if you took those strands of spaghetti and tied them together in places, the strands would not be able to slip and slide around nearly as much! The borax and glue mixture is just like your knotted spaghetti!
*Where can I get Borax powder?
In Ireland you need to buy Borax powder in a pharmacy. The production is a little erratic and the larger volumes are no longer available! You should be able to get this 100g tub in any pharmacy and it costs about €2.25.
UPDATE 2017: Borax powder is no longer as readily available in Ireland. here is one alternative, using very simple ingredients… check out this post on how to make silly putty.
Or check out our Ultimate Slime Guide for lots of fantastic slime recipes using contact lens solution or laundry detergent.
Check out next week’s Fun Friday post for more slime recipes to try at home!
I had great fun preparing for the third, and final part of this blog series. It is all well and good discussing the merits, scientific and otherwise, of using vegetables in your baking, but as a truly dedicated scientist I realised a little R & D was also required. Time to don the apron and turn on the oven, but which recipes to choose? I am very keen to try Dee’s Beetroot Chocolate Cake from which these blogs were inspired but I wanted to introduce some other vegetables for this blog. When I posed the questioned through social media I was delighted with the number and variety of recipes recommended. I needed to choose my parameters and narrow down my study field.
I started to ask the question… “what vegetable would really convince you?”
photo credit: Tommy Hemmert Olesen via photopin cc
Most people are familiar with the carrot cake and enjoy it as a bone fida cake, so carrots were already out there. This, in my opinion, excluded the parsnip too and many other vegetables that are known to be high in sugar content. Someone mentioned the potato and it seemed like a very good starting point to me… its high starch content makes it an obvious substitute for flour in baking, but in my head it still belonged on my dinner plate along with bacon and cabbage. It was easy to find a recipe using potatoes in cakes and I chose to try some mini chocolate cupcakes.
photo credit: Timothy K Hamilton via photopin cc
My husband said if I managed to bake a tasty cake containing green leafy vegetables it would definitely convince him. I had to admit he made a good point. Green leafy vegetables are not known for their sweetness and definitely not what I would be reaching for when creating a sweet treat. Not one to shy away from the challenge I decided that a spinach cake was next on the list.
photo credit: Theophilos via photopin cc
I liked these choices, but for me there was one vegetable missing. My ultimately convincer would be a tasty cake containing mushrooms! (I know, I know these are not technically speaking vegetables, but if you refer back to the first blog in this series, I did say I would be including it too!) .
I do love the taste of mushrooms but, try as I might, I could not imagine the taste of a sweet mushroom cake. My brain just could not compute that one… or else I felt a bit queasy every time I tried too. So mushroom cake just had to go on the list.
That was my three vegetables picked, so I got down to some baking… with a few little chefs eager to help!
Once the baking was finished I had plenty of taste testers to give their verdict, friends, neighbours… and especially family! Along with the recipes that I share below, I have also included the feedback and opinions I received. At the end of this blog I share some tips and advice suggested by others along with some other vegetable cakes that I didn’t get around to trying yet.
My most enthusiastic Taste Testers….
The taste testers
Potato Chocolate Mini Cupcakes
Here is the original recipe for those who prefer these measurements. Personally, I still like to work in kg/g (or lbs/oz) so I have converted the measurements and share them below…
For the Cupcake:
60g butter (at room temperature)
65g sugar
1 tsp vanilla extract
1 large egg (room temperature)
60g mashed potato (cool and unseasoned)
3 tbsp milk
80g plain flour
3 tbsp cocoa powder
3/4 tsp baking powder
pinch of salt
For the Ganache:
120 ml cream
1 tbsp butter (room temperature)
100g dark chocolate
Method:
Preheat the oven to 190oC and place mini cupcake liners in cupcake tray.
Beat the butter and sugar together until light in colour.
While still mixing add the egg, vanilla and mashed potato and beat until smooth.
Sift the flour, baking powder and salt into a separate bowl and then add to the butter mixture.
Stir until evenly combined.
Spoon batter into miffin cups, filling each about half full.
Bake for 10 – 12 minutes.
Allow cupcakes to cool completely, in the tray, before adding the ganache.
To prepare the ganache, warm the cream and butter over a low heat until just below simmer.
break the chocolate into small pieces in a heat proof bowl.
Pour the heated cream/butter mixture over the chocolate and allow to leave for one minute to allow the chocolate to melt.
Whisk until smooth and pour over the cupcakes.
Add desired sprinkles or toppings of using.
Allow to cool completely before serving.
From this…
…to these…
… with a little help from these!
The potato provides us with Vitamins A, B and C, Potassium, Calcium and IronThe Results and feedback:
These mini cupcakes turned out well. The potato gave them a nice texture but there was no taste of the vegetable at all. No one was able to guess the mystery vegetable ingredient!
Although I liked these cupcakes and they kids did too, giving them a six out of ten, I felt that the ganache was a bit too strong for my liking and some others agreed. If doing this one again I would maybe change the dark chocolate for milk or change the topping entirely. The cupcakes taste good on their own, light and moist too.
Spinach cake
I thought I would find it difficult to source a Spinach cake recipe but it turns out it is a traditional Turkish cake. I based this cake on this original recipe.
Ingredients:
250g Spinach
180 ml Olive Oil (preferably Extra Virgin)
2 tbsp Lemon juice
1 tsp vanilla extract
3 eggs
250g sugar
220g flour
3 tsp baking powder
pinch of salt
Method:
Preheat the oven to 180oC.
Wash the spinach and remove any large stalks.
Add spinach, olive oil, vanilla and lemon juice to bowl or blender and blend until pureed.
In a separate bowl beat the eggs and sugar together until light and creamy.
Add the spinach puree to the beated egg and sugar and mix well.
Sift the flour, baking powder and salt into another bowl, make a well in the centre and add the egg/spinach mix.
Fold together until uniform.
Pour into a greased pyrex dish or into prepared cupcake liners – I made one loaf (5 X 9 inch) and six cupcakes from this mixture.
Bake at 180oC for 30 minutes (20 minutes for cupcakes).
Allow to cool before removing from baking tin.
Tastes good served with whipped cream!
Spinach cake … yep it was GREEN!
The results and feedback:
This one was a BIG hit!!! I called it “Kermit Cake” when offering it to the kids and they could not guess that it was made of Spinach. More importantly, it did not put them off when they found out! My seven year old wouldn’t usually eat spinach if his life depended on it but he could not get enough of this cake. All three kids gave it ten out of ten and it was popular with adults too. One person guessed the mystery vegetable ingredient, which surprised me as I could not detect it at all!
I would definitely bake this cake again!
Spinach is full of vitamins (A, B, C, E and K) as well as Iron
Mushroom Cake
Next up was the mushroom cake, I had my doubts about this one and originally considered adapting a recipe for rhubarb muffins but then Dee pointed me to this recipe she had found.
Ingredients:
125g butter (at room temperature)
150g sugar
1/2 tsp vanilla essence
2 large eggs
240g wholemeal flour
120 ml milk
400g button mushrooms, washed, dried and grated
75g chopped walnuts
2 tbsp honey
Method:
Preheat the oven to 180oC and grease and line 20cm springform cake tin.
Place butter and sugar in a bowl and beat until light and pale.
Add one egg at a time and mix well between additions.
Add the flour and milk, in small amounts, keeping the mixer on a low setting, and ensure each addition is well mixed in before adding the next (i.e. add flour, then mix, then milk, mix, flour again etc).
Add the mushrooms and mix well.
Add the chopped walnuts and honey and mix until all ingredients are thoroughly combined.
Pour batter into prepared tin and tap base to remove any air bubbles.
Pop in the oven and bake for one hour.
Turn off the oven and allow cake to cool gradually with oven door ajar.
Once cake is cool remove from baking tin.
Mushroom Cake… very moist, very heavy and tasted of….mushrooms!
Results and feedback:
This was a very dense, moist cake and despite me leaving it in the oven for extra time, there was no denying the taste of mushrooms! Not a cake I would be reaching for again and the feedback overall was similar. The mushroom taste was too strong and put most people off.
Disappointing! I let this one mull around in my head for a few days but then decided to give it one more try. This time I would go back to my original idea and try to incorporate mushrooms in place of rhubarb in my favourite breakfast muffin recipe.
The original recipe comes from Nigella Lawson’s wonderful book Feasts but I have modified it quite a bit at this stage.
Mushroom Breakfast Muffins
Ingredients:
250g soft brown sugar
80 ml vegetable oil (I usually use sunflower oil)
1 large egg
2 tsp vanilla extract
250 ml buttermilk
150g mushrooms, washed, dried and grated
75g chopped walnuts
200g wholemeal flour
100g plain flour
50g milled seeds (such as linseed/sunflower)
2 tsp baking powder
1 tsp bread soda (bicarbonate of soda)
Topping: mix 2 tbsp on Demerara sugar with 1 tsp on ground cinnamon.
Method:
Preheat the oven to 180oC and place liners in the muffin tray.
In one bowl mix the sugar, oil, egg, vanilla and buttermilk.
Stir in the grated mushroom and chopped walnuts.
Add the wholemeal and plain flour, milled seeds, baking powder and bread soda.
Fold these into the mixture with the minimum amount of mixing.
Spoon into prepared muffin liners and sprinkles with the cinnamon and sugar mixture.
Bake in the middle of the oven for 20 minutes.
Enjoy!
Mushroom Breakfast Muffins…. Yum!
Result and feedback:
This time it was a winner. These muffins were as delicious (or almost) as their rhubarb cousins but with no taste at all of mushroom! The texture and moistness were just right. They were a hit with anyone who tried them and no one guessed the mystery ingredient this time!
Mushrooms contains all five B Vitamins as well as essential minerals and Selenium
Suggestions and tips:
As I mentioned, there were a lot more vegetable cakes I could have tried. I did actually also try a Chocolate and Aubergine Cake (gluten free) that Aedin from FreeFromGuru had previously shared with me and brought the cake to a gluten free barbecue where it proved very popular… again no taste of aubergine. Unfortunately I deleted the photos of the cake but you can check out the recipe here.
I really enjoyed trying out the recipes for this blog …and tasting them. The feedback from all my taste testers was very promising. This experiment has really changed the way I think about vegetables and YES I am converted to the concept of using vegetables in my baking. Now I am reviewing my favourite recipes, wondering how I can incorporate various veggies.
The things that pleased me most about all this are…
my children happily eating a spinach cake!
surprising myself with a cake that contained mushrooms… and tasted GOOD!
the enthusiasm and feedback that everyone gave in response to the idea of vegetables in baking!
I hope you have enjoyed this series on vegetables in baking and would consider giving it a go. If you have any comments or suggestions, or if you have some recipes to share please drop me a line in the comments below… I would love to hear what you think!
Last week’s blog post sparked a lot of discussion and debate on the topic of vegetables in (sweet) baking. It seems that everybody has an opinion, some are surprised with the idea, some are keen to try it and many already have and offered some great recipes. I have really enjoyed baking with various vegetables myself… and seeing the response of my taste testers, but more of that next week…. this week I promised to discuss how vegetables contribute more than just sweetness to the baking.
What else is there?
Last week I mentioned that vegetables contain starch. Wheat flour typically used in baking contains up to 75% starch. Many vegetables such as potatoes, peas, corn and squash have a high starch content also. It is a grainy substance contained within the plant cells.
So what does starch contribute to baking ?
Potato starch granules in potato cells; Image credit: Dr. Philippa Uwins via Wiki Media Commons
Starch is referred to as a complex carbohydrate. The carbohydrate bit means it is made up of carbon, hydrogen and oxygen. The complex part means that the structure of starch is a long chain of these carbohydrates molecules all linked together in a chain. The carbohydrate is starch is the sugar glucose and starch is composed of a chain of hundreds of glucose molecules.
Starch is typically tasteless and odourless, its contribution in baking is a structural rather than flavoursome one. In the presence of heat and moisture starch granules will begin to swell and thicken. These swollen starch complexes form a scaffolding like network within the mix. When gluten is present it breaks down with heat and the starch absorbs the water it releases making the gluten dry and rigid, strengthening the structure even further. This starch-gluten structure gives baking its texture and rigidity and allows it to keep its shape once out of the oven.
When vegetables are used in baking the amount of flour required is reduced. This substitution of a natural starch in place of a refined one not only makes for a lighter, less stodgy cake, it also improves the nutritional content. Vegetables are packed full of vitamins, minerals and fibre. These all contribute to the positive health of our skin, hair, digestive system, mood, cholesterol levels and brain power.
What about a bit of water?
Vegetables also have a high water content which can contribute to the moistness of the cake. The baking process allows the water to be contained within the cake as well as helping to retain the vitamins and minerals. Vegetables with a high water content include courgettes, spinach, peppers, tomatoes, peas and aubergines. This added moisture also keeps the cake fresher for longer, meaning it can be enjoyed over several days without drying out …. that’s if it lasts that long of course.
Tomatoes are made up of 94% water
Texture
Adding vegetables to baking changes the texture of the final product. As I mentioned last week, vegetables contain fairly high levels of cellulose, a fibre. In fact cellulose makes up about one third of all vegetables. This cellulose serves a structural role in the plant cells, along with smaller polysaccharides called hemicellulose. The presence of both of these greatly changes the texture of the cake. The cellulose is broken down, in part, during the baking process and this also contributes to the structure (rising) of the cake. However, cellulose still maintains a crystalline structure at the high temperatures typical of baking, and these granules directly contribute to the texture of the cake. Studies have shown that smaller granules of cellulose can yield more favourable rising of bread and other baking allowing for a lighter consistency.
Beetroot Chocolate cake; Image Credit: Dee Sewell of Greenside Up
Beetroot gives a lovely texture to Dee’s Chocolate cake!
The final word
So there you have it… not only do vegetables contribute a lovely sweetness to baking but they play a major part in the structure, moisture and texture of the cake. Surely you must be convinced by now? If not make sure to check back next week for the final part of this blog series when I will be sharing some recipes I have tested and the response they have received.
Tune in next week for Part 3 of the series where I will be sharing lots of recipes and letting you know what people thought.
In the mean time… if you have any comments, tips or experience to share please leave a comment below; I always love to hear from you and will be sure to reply!
Now that I have entered the world of blogging I enjoy reading other blogs as much as I do writing and researching this one. I have some favourites that I check in to regularly as a little treat; chief among them is the Greenside Up blog! Written by the lovely Dee Sewell, this blog brings together garden, community and kitchen, always with a refreshing, informative and jovial note! Last week was no exception as Dee shared a recipe for Beetroot Chocolate cake. The post not only extended my baking “to do list” but also posed the question…
“Why do vegetable work so well in baking?”
The concept is fairly new to most of us (although we are all familiar with the carrot cake) but is growing in popularity. With good reason too, it seems. Tempted, or completely put off by the idea?… I have prepared a short series of blogs to explain a little of the science behind the concept and hopefully to convince you to give it a go!
In this first blog I will look at the sugar content of vegetables and how it contributes to the flavours in the baking.
Firstly, what defines a vegetable?
photo credit: Marj Joly via photopin cc
We can be a little more specific when defining a fruit as its botanical definition is the ovary of the flowering part of the plant; to put this more simply it is any fleshy material covering the seed, or seeds, of a plant. In general people tend to define a vegetable as a plant used in savory meals and a fruit as a sweet option.This is a tricky one as there is no real scientific definition of a vegetable. Although there are some generally held guidelines these too vary depending on the classification, criteria used and even the Country you live in. The most common definition of a vegetable is a plant grown for culinary use.
So far, so good, right? However you don’t have to look too long to find that the lines are very blurred …. for example, in the botanical sense courgettes, tomatoes, pumpkins, squashes and avocados are actually fruit. Then there is the question of whether mushrooms are vegetables (technically speaking they are not plants but fungi); and what about potatoes? Due to their high starch (carbohydrate) content they are grouped with rice, bread and pasta and are not included as one of our “five a day”.
So the truth of the matter is I cannot actually define a vegetable for you. All I can say is that, for the purpose of this blog, I am going to lump all these in together as vegetables…. potato, tomato, courgette, even the mushroom (although as a scientist that one grates on me a little)!
Why use vegetables in (sweet) baking?
We all enjoy a nice baked cake now and again and naturally associate the sweetness of fruit with the sweet treat. No one needs to be persuaded of the virtues of a lovely homemade apple tart! The key to adding fruit is, primarily, to exploit and enjoy the sugar contained within. When we think of vegetables we tend to think of a more savory dish, however vegetables do contain sugars as well as fruit, and some in quite significant amounts. Some of the sweetest vegetables include carrots, beets, peppers, potatoes, peas and corn. Just to give you an idea….carrots contain approximately 4 grams (g) of sugar per 100 g, while beetroot contains up to 8 g per 100 g. Compare this to an apple that comes in about 10 g sugar per 100 g or a strawberry, about 4.5 g per 100 g. We begin to understand why Dee’s Beetroot Chocolate Cake was so well received by her family!
Beetroot Chocolate Cake; Image credit: Greenside Up
What sugars do we find in vegetables?
Now we begin to realise the extent of sugars present in many vegetables, but what kind of sugars are they?
photo credit: howzey via photopin cc
Another sugar found naturally in vegetables is Sucrose, what we know as common table salt. Sucrose is made up of the two sugars glucose and fructose. Most plants make sugar through the process of photosynthesis. Vegetables make a simple sugar called glucose in this manner. Glucose is a single sugar molecule that is the ultimate energy fuel for our brain and body.
Long chains of glucose form the polysaccharide known as starch. The longer a vegetable is left on the plant the more likely it is to convert its glucose into starch for storage purposes. We are able to consume this starch and break it back down into its glucose molecules.
Finally, vegetables also contain sugar in the form of fibre, known as cellulose. We do not metabolise cellulose very well and do not absorb the component sugars into our bodies. Fibre is a necessary part of our diet though and helps us to maintain a healthy digestive system and a balance of good bacteria within our intestine.
The Maillard reaction
So why do we consider vegetables a more savory dish if they are so full of sugar? The answer lies in the way we cook them. Firstly we need to understand a little of the science behind the process.
I have talked about the Maillard reaction in a previous blog, but feel it needs another mention here as it is primary to the discussion of baking, vegetables and sugar! The Maillard reaction was developed in 1912 and is named after the French Scientist who first proposed it! Basically it says that when you mix sugar and amino acids (protein) at high temperatures they react to form a variety of different flavours and aromas.
When we add vegetables to our baking the high temperatures of the oven allow the aldehyde group of the simple sugars found in the vegetables to react with the amino (nitrogen) group of the proteins present in the mix to create a variety of pleasant tasting compounds.
When we boil or steam vegetables the heat and moisture do not lend themselves to the browning/sweetening reaction described by Maillard, therefore they have a much more savory taste. If you need a little convincing just try a little experiment of your own…. prepare a vegetable such as carrot, beet, squash or pepper in two ways… boil one lot and roast the other. A quick taste test should convince you what Maillard was talking about, even if the Science is a little baffling, even to the Scientists!
Tune in next week when I will discuss how vegetables contribute to the texture of baking, while Part 3 of the series will be the “proof in the pudding” blog with lots of tasty recipes to try.
In the mean time… if you have any comments, tips or experience to share please leave a comment below; I always love to hear from you and will be sure to reply!
My three year old got up from kneeling the other day and started to wiggle and jiggle a little, when I asked him if he was OK he said…
…”Mummy, I’ve got sparkly toes!”
“Mummy I’ve got sparkly toes”
That has to be the cutest description of pins and needles I have ever heard. He looked at me a little confused and wanted to know why his toes were sparkling… I gave him a simple explanation but even as I was talking… I could feel a blog coming on!
So what are pins and needles and why do we get them?
Parasthesia is the medical term for pins and needles. The pins and needles that most of us experience, just as my son did, are a result of pressure on a nerve, restricting its blood supply. This pressure is usually a temporary pressure caused by us leaning on a limb or part of the body in an awkward way.
This pressure on the nerve restricts its supply of blood and therefore prevents it from “charging up” and “firing off” in the usual manner. The signalling pathway gets interrupted resulting in the nerve firing off incorrectly or at a modified rate… and we feel this as a fuzzy, tingling, spiking sensation. If the nerve is suppressed for too long its signalling function stops all together and the area becomes numb. These sensations can usually be quickly and easily reversed by simply changing position and moving the area that is affected, thereby returning blood supply to the nerves.
A closer look
So now we have a general understanding we need to know how nerves operate to explain the phenomenon a little further. Nerves carry messages around the body; these messages can be transferred from one part of the body to another or from a part of the body to the brain, or vica versa. Nerves are made up of bundles of cells called neurons.
Unlike most cells in the body, neurons do not regenerate, this makes them among the oldest cells of the body
The longest cells in the body are neurons
Neurons are very specialised cells: they transmit electrical signals (nerve impulses)
Nerve impulses travel at a speed of approximately 25 metres per second
Neurons have a very high metabolic rate
When the sensation is a little more serious
It is this high metabolic rate that causes the nerves to start to shut down their process. If the blood supply to the nerve is cut off or reduced (as is the case when we are sitting on a limb) they cannot produce enough energy to keep recharging themselves so the smallest neurons start to operate more erratically. These small neurons are the ones that transmit signals of pain, hence the first sensation of pins and needles.
Certain medical conditions are associated with prolonged or chronic pins and needles. The sensation may be due to a trapped nerve or nerve damage or infection. It may also be due to exposure to certain toxins or medical drug treatments or alcohol. Chronic parasthsia can be a side effect of diabetes, hyperventilation, vitamin B 12 deficiency or malnutrition.
The sensation of pins and needles usually goes very quickly once the blood supply is re introduced to the area affected, however if the symptoms persist or reoccur it is best to seek medical advice.
Hope you enjoyed the blog, if you have a question, a comment or an idea for a topic you would like me to cover in a future blog please leave a comment!
Some of the best “gems” we get from our children are those moments before they go to sleep. Our children are still young enough to want five minutes with Mum or Dad at bed time. As frustrating and distracting as I sometimes find the task, once I lie down in the bed next to them and tune into their thoughts and ramblings, I am always grateful that I took the time.
In fact, these precious moments have been the inspiration for many of my blog posts here. This one is no exception… I lay down with my nine year old daughter last night at bedtime and the first thing out of her mouth was…
…”Mom, how many times do we blink in a day?”
Humans usually blink about 10 to 20 times a minute. A blink flushes the eye with fresh tears, supplying essential nourishment to maintain a healthy eye surface. This can refresh the eyes, clear away any dust and debris and prevent infection. Blinking can also brighten and refresh images received by the retina.
How long does a blink last?
A blink typically lasts about half a second. If you add all this up we actually have our eyes closed for at least 120 minutes a day. Blinking does serve the necessary purpose of moisturising the ocular surface but apparently the rate at which we blink exceeds the requirement for clearing the eye. So are there other reasons for this process?
Yes!Recent studies have shown that blinking also gives our brain a little “nap”, switching from cognitive to non-cognitive focus (from conscious focused mode to day-dreamy imagination mode), a “micro” respite from the task at hand. This process allows us to “reboot” and refocus!
Do women blink more than men?
When I mentioned to my husband that I was writing this blog on blinking he said “Oh, do you mean how women blink more often than men?” I went off, a little indignant to double check, and I am happy to report that this one is a myth. There is no discrimination between the sexes on blinking rate. Other factors, such as fatigue, environment and medication can of course effect how often we blink.
Blinking and social cues?
Although we tend to blink unconsciously we do still follow certain social cues or natural pauses. An interesting study observing an audience watching a short video found that they synchronized their blinking to occur at points in the video that required less attention or where they were less likely to miss something of importance.
During social conversation we are more likely to time our blinking with pauses in speech, both for the person talking and, a second or two later, the person listening.
The frequency of blinking also depends on the particular type of social interaction and the emotional state of the person. Blink rate tends to increase after a lie has been told, for example, but remains unchanged when telling the truth. Stress, anger and anxiety also increase blink rate. People suffering from depression have exhibited faster blink rates as well as those with certain mental health issues.
What about blinking in other animals?
Some animals (such as the tortoise) blink their eyes independently of each other. Some have a very slow blink rate (such as cats and rabbits).When birds blink their lower eye lid comes up to meet the upper lid, in mammals it is the reverse.An interesting study conducted on the blink behaviour of 71 different species of primates reported a correlation between primate size and increased blink rate. Of even more interest was the observation that blink rate increased in species that lived in larger greater group sizes and experienced more social interaction.
Blinking and Art…
I came across an interesting reference to blinking while writing this blog that I thought it was worth sharing. It refers to the famous Mona Lisa painting by Leonardo da Vinci. The enigmatic face of Lisa Gherardini captured on the canvas has lead to centuries of speculation as to the secret behind her smile. It appears that da Vinci used a layering and blurring technique that causes our eyes to re-adjust every time we blink, thus restarting the puzzling scrutiny of that mysterious expression.
It is Father’s Day here in Ireland. A day to reflect on our own bonds and experiences with that special man in your life that has known you since birth! My own story is a wonderful one, my Dad and I are very close and my life memories are filled with lots of special moments with him.
My Dad meeting his 6th grandchild for the first time!
I have a lot to thank him for…
…the weekends he gave up to bring me to yet another horse riding competition or event (only really appreciated this one when I had kids of my own, up until that it never occurred to me that he would have anything else to do ;0) )
…the lovely way he explained to me how special I still was to him when my little sister was born!
…the day he took off from work and brought me to Galway to see what a nice place it was… this was after I got my “Leaving Cert” results and realised my dreams of becoming a vet were gone… he knew me well enough to know not to try to talk me out of my “depression” but to open my eyes to other possibilities in a different way! Considering I have now lived in Galway for most of the past 24 years, I think he can chalk that one up as a success!
…the way he stayed up all night reading my PhD thesis when I first showed it to him… and I mean ALL of it… he even had the typos and edits ready for me the next day!
…the way he treated every drawing, every card, every poem I gave him as a child as an amazing work of art… in fact it seems he still has them all!
…the way he is still the one I go to for advice!
…the way the sound of his voice will still make me cry if something has just upset me.
…the way I can see our bond live on with his relationship with my children!
So I thought today would be a good day to reflect on what a wonderful man he is… and to take a look at the science behind the bond between a father and his children.
A lot has changed in a father’s role since I was born. My Dad was certainly not present at my birth, he was at work and came to see me once he got the call that his first daughter was born! By the time my own children were born things were very different…my husband was not only present at their births but was actively involved in the whole process, he was my “hypnobirthing” partner and helped me stay relatively calm and focused throughout each birth!
My Dad was also not as “hands on” as most men are now… nappy changing, bottle preping and the like were not really part of his repertoire. However there is no denying the strength of the bond he has with all three of his children.
The science behind the bonding process between mother and child is more commonly known and understood but there is a definite and undeniable bond formed between father and child also, and although less studied there are many scientific explanations emerging.
It is now known that expectant fathers may also experience hormonal changes coming up to, during and after the birth of their child. Studies have shown a drop in levels of testosterone and an increase in prolactin and cortisol levels in men during the weeks coming up to the birth. These hormones are more commonly associated with expectant mothers. Prolactin levels are also seen to be higher in fathers than in men with no children, and higher in fathers with young children than with older children.
Studies have also shown an increase in oxytocin levels in fathers after the birth of their child. This is the hormone that is strongly associated with aiding strong bonding between mothers and their babies. Fathers have shown an increase in active play and interaction with their infants after receiving oxytocin.
Research is still ongoing into the reasons for these hormonal changes and more importantly the role they play in forming and strengthening the male parental bond. It is possible they play a role in calming fathers, in increasing their sensitivity to the smell and touch of their young children and in encouraging more play and interaction between father and child. In other words they may help dampen down the aggressive side of the male and bring out his “inner child”!
Regardless of the science and the research behind it, there is sometimes no need to examine and explain the love, care and affection between a father and his children…
….so today I want to say a big HAPPY FATHER’S DAY to my wonderful Dad and a big thanks for all the love, support and encouragement he has always given me! I hope you like my unconventional gift Dad x
Clouds are made up of tiny drops of water or ice crystals. They form when warm air picks up water vapour from the land or sea and carries it into the sky turning it into water droplets or ice crystals!
The study of clouds is called Nephology.
Let’s learn more!
There are lots of ways to describe clouds but they are usually named based on their height in the sky, their shape or the weather they can bring!
If a cloud name starts with “cirr-” then you know it must form very high in the sky (over 20,000 feet).
If a cloud name has “Alto”- in it then it is in the middle section of the sky (between 6,500 and 20,000 feet).
Clouds with “Strato-” in the name are found in the lowest part of the sky (below 6,500 feet).
The clouds that are really high in the sky are mainly made up of ice crystals as the air is so cold.
Clouds at ground level are called “fog”.
Did you know…all clouds are white but can appear grey or dark when seen from below? This may be due to the amount of water they contain and shadowing by clouds above them.
Clouds named according to their shape will contain one of these Latin words in their name…
Therefore a cloud named Altostratus would mean a cloud that forms in layers and sits between 6,500 and 20,000 feet above land.
Did you know... other planets contain clouds made up of chemicals other than water? Venus has clouds made up of sulphuric acid, chlorine and flouride. Neptune is covered by bright blue methane clouds!
The latin word “Nimbus” is used to name rain clouds!
Clouds called Cumulonimbus are often referred to as thunder clouds as they usually bring thunder storms!
Cumulonimbus clouds are the tallest of all the clouds.
Cumulonimbus looks a bit like a giant cauliflower in the sky!
Did you know… a sinlge cloud can hold billions of pounds of water?
Clouds are carried along by the wind and can often travel quite fast;
Thunder clouds (Cumulonimbus) usually travel about 64 kilometres per hour (kph). The highest clouds (above 20,000 feet) can reach speeds of over 160 kph!
An experiment to try at home:
Make a cloud in a bottle!
You will need… an empty 2 Litre plastic bottle, warm water and a match.
What to do… Fill the plastic bottle one third full with warm water. Put the cap back on and squeeze and then release the bottle. Nothing happens. Ask an adult to light the match and put it into the bottle. Replace the cap quickly. Try squeezing and releasing the bottle again. What happens this time?
So what is happening?…Once the match has been added to the bottle a cloud forms when you squeeze and then release the bottle (if you squeeze again the cloud dissapears and reappears when you release). To make a cloud you need water vapour, small particles (like the smoke) and a decrease in air pressure.
Our garden is bursting with life at the moment! Busy, haggard birds are flitting around, building nest and laying eggs. Insect populations are slowly emerging and even our hens are getting broody! For the first year ever we have a number of young rabbits joining in the ecosystem that is our back garden. The rabbits in particular have attracted the children’s attention. You can understand why… there must be at least five of them and they are very tiny, very cute and very independent! That got my children wondering….
Rabbits are independent from a very early age. A female rabbit (called a Doe) will give birth to a litter of four to twelve baby rabbits (called Kits). The kits are born blind and without any fur. However within a week their eyes have opened, their fur begins to grow and their ears begin to stand upright. Wild rabbits will begin to wean about two weeks old and within three weeks they have grown enough to leave the nest and live independently. They may look small and helpless in our back garden but they are old enough to go it alone in the wild.
A doe can reach sexual maturity between three and six months and can live for up to ten years. The breeding season of rabbits usually last three quarters of the year. The most amazing aspect of the rabbit though, is that fact that the doe has no oestrus cycle. She can literally get pregnant a day after giving birth. Her gestation period is only one months long.
If you want to do the maths on all that it means that one doe could give birth to up 80 to 100 kits a year, or as many as 1,000 kits in one lifetime. With these turnover rates you can see why the kits have to be independent pretty quickly!
The busiest members of the garden seem to be the birds. Nest building, egg laying and then feeding a brood of hungry and demanding chicks. For the first part of their lives these chicks are completely dependent on their parents for food and the parents spend the early summer months on a non stop conveyor belt of foraging and feeding. The chicks learn to out “beg” their siblings rather than how to feed themselves. Of course this does not last for long, eventually these young birds will learn to fly and forage all by themselves … no mean feat!
Why do birds choose to feed rather than encourage foraging at an earlier stage? By evolving in this manner birds can choose to build their nests in more isolated, out of reach places, such as high up trees or on cliff edges. The compromise is that such places do not have a ready supply of food so the parents must go and source the food and bring it back. Although an exhausting process, the chicks are more likely to survive!
WHAT ABOUT THE INSECTS AND THEIR YOUNG?
This one depends on the insect obviously. Most insects’ parenting work ends with the lay of their eggs. This they usually do in large quantities, to increase the chances of survival of at least some of their progeny. Once the young hatch they are on their own! Often having to work their way through a number of different forms and changes before they even make it to adulthood! Imagine what it must be like to morph from a grub to an adult? Must be like going through your teens without any parental guidance what so ever!
Not all insects leave their young to their own devices of course. Some bee, wasp and ant species tend to the eggs in colonies of nests or hives. Once the larvae emerge from the egg they are fend and tended to completely, passing through different developmental stages until they pupate and emerge as adults.
HOW DO HUMAN INFANTS COMPARE?
The insects and birds mentioned above rely on their young doing most of their development outside the adult body, in eggs and/or larval stage. They are not mammals (giving birth to live young) like rabbits or humans. We have seen how quickly the rabbit young develop and gain independence from their mother. This is not the case with human infants though. So why the big difference between the dependence of the young in rabbits and humans?
Factors that influence the level of dependence of young on the adult can include…
size of the fetus
size of the mother
number of young per birth
brain size and growth rate
cultural behaviour of the species
life span
Rabbit have large litters, short gestation periods, a less developed brain and a shorter life span than humans. These facts all explain the difference in dependence of young.
If we look at all mammals we find that humans have very dependent young relative to most other species.It is thought that our evolution into bipedal (walks on two legs) creatures has meant that our young must be born with smaller brains and that the brain develops more after birth. This is for physical reasons: in order to walk upright the size of our pelvis is restricted and therefore the size of the infants we give birth to is restricted.
To examine infant dependence even further we can compare the dependence of human young with those of other primates; Human infants are much more underdeveloped at birth than their primate relatives! In fact human development is thought to take 30% to 50% longer than that of other primates. Why is this the case? Perhaps it goes back to the point that life span may play a role in infant dependence? This point alone does not account for the big difference observed between humans and other primates. Other suggestion that might contribute are the nutritional demands on the mother during gestation and the amount of growth and development the brain will undergo after birth.
Scientists are now also looking at the contribution of maternal nurture and the cultural development of the society of the species. Humans have evolved a highly developed social and cultural environment. We have developed complex communication methods (e.g. language and social ques) and cultural interactions. In order to fit into such a complex system, perhaps the human infant must learn by observation and inclusion… neither of which it can do in the womb. Maybe we are born with such underdeveloped brains because most of our development and learning can only be done in the culture within which we will live!
A rocket can describe any object that is propelled by fast moving liquid or gas!
Most rockets have a nose or cone at the top, a body that houses the fuel and fins at the base.
Rockets are usually powered by a chemical reaction (explosion) within the rocket itself. This chemical reaction requires both fuel and oxygen, both of which must be carried within the rocket.
The fuel and oxygen are called the propellant. There are two types of propellant, liquid propellant and solid propellant.
A solid propellant rocket is easier, simpler and cheaper to make. However, these rockets are harder to guide and control as once the chemical reaction is started it is hard to stop.
A liquid propellant rocket is more complex and expensive to make but the burning of the liquid fuel is allot easier to control.
photo credit: Flying Jenny via photopin cc
A bit of history
The Chinese were the first to invent rockets when they started filling bamboo tubes with gunpowder and lighting them.
Rocket science really began with an English man called Isaac Newton. He formulated three laws to explain the physics of motion. These laws explain how rockets work!
Newton‛s 3rd Law of Motion states that every action has an equal and opposite reaction!
To understand this law think of a balloon full of air.
Demonstrating Newton’s 3rd Law of Motion
If the balloon is untied and the air suddenly let out, it will escape the balloon with such force that it will propel the balloon in the opposite direction.
The force of the air leaving the balloon is called the thrust! The thrust that powers the launch of a rocket comes from the force of the gas (generated by the burning fuel) being ejected from the rear of the rocket!
The first liquid propellant rocket was launched in 1926 by an American called Robert Goddard. He is considered the father of modern rocket science!
Rocket to the Moon
Neil Armstrong… photo credit: NASA’s Marshall Space Flight Center via photopin cc
In 1969 Neil Armstrong and Edwin Aldrin became the first men on the moon.
Armstrong and Aldrin traveled to the Moon in a rocket called Saturn V. It was 100 metres tall and weighed more than 3,000 tonnes! It was the largest rocket ever launched!
An Experiment to try at home
Make a stomp rocket!
You will need… an empty 2L plastic bottle, paper, insulation tape, a 1/2 inch PVC pipe, a length of rubber tubing;
What to do… tape one end of the rubber tubing to the neck of the bottle and tape the other end to one end of the PVC pipe. Next make the body of the rocket by wrapping a piece of paper around the PVC pipe and secure it with tape at the overlap. Remove the rocket from the pipe. Cut four triangles of paper and attach to the body of the rocket near one end; these are the rocket fins. Make a nose (cone shape) for the other end of the rocket and attach it with tape. You are now ready to launch your rocket. (Best to do this outside!).
Sit your paper rocket over the PVC pipe and place the 2L bottle on the ground on its side. Stomp on the bottle and watch your rocket shoot off!
This is what your stomp rocket should look like
So what is happening?… when you stomp on the bottle the air inside it shoots out through the tubing and the pipe, forcing the rocket off the end of the pipe! Just blow into the pipe to re-inflate to bottle to start again!
An Experiment to try at home
Make a teabag rocket
I have shared this one with you before, but for those of you who have not seen it I thought it would be a nice addition here…. a double for the Bank Holiday Weekend ;0)
If you try any of the experiments or have any comments or questions, please let me know in the comments below!
