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They might be short-lived — but between the time a bubble is born (Fig 1 and Fig 2a) and pops (Fig 2d-f), the bubble can interact with surrounding particles and microorganisms. The consequence of this interaction not only influences the performance of bioreactors, but also can disseminate the particles, minerals, and microorganisms throughout the atmosphere. The interaction between microorganism and bubbles has been appreciated in our civilizations for millennia, most notably in fermentation. During some of these metabolic processes, microorganisms create gas bubbles as a byproduct. Indeed the interplay of bubbles and microorganisms is captured in the origin of the word fermentation, which is derived from the Latin word ‘fervere’, or to boil. More recently, the importance of bubbles on the transfer of microorganisms has been appreciated. In the 1940s, scientists linked red tide syndrome to toxins aerosolized by bursting bubbles in the ocean. Other more deadly illnesses, such as Legionnaires’ disease have been linked since.

Bubbles are formed whenever gas is completely surrounded by an immiscible liquid. This encapsulation can occur when gas boils out of a liquid or when gas is injected or entrained from an external source, such as a breaking wave. The liquid molecules are attracted to each other more than they are to the gas molecules, and this difference in attraction leads to a surface tension at the gas-liquid interface. This surface tension minimizes surface area so that bubbles tend to be spherical when they rise and rapidly retract when they pop.

When microorganisms are near a bubble, they can interact in several ways. First, a rising bubble can create a flow that can move, mix, and stress the surrounding cells. Second, some of the gas inside the bubble can dissolve into the surrounding fluid, which can be important for respiration and gas exchange. Microorganisms can likewise influence a bubble by modifying its surface properties. Certain microorganisms secrete surfactant molecules, which like soap move to the liquid-gas interface and can locally lower the surface tension. Microorganisms can also adhere and stick on this interface. Thus, a submerged bubble travelling through the bulk can scavenge surrounding particulates during its journey, and lift them to the surface.

When a bubble reaches a surface (Figure 2c), such as the air-sea interface, it creates a thin, curved film that drains and eventually pops. In Figure 3, a sequence of images shows a bubble before (Fig 3a), during, and after rupture (Fig 3b). The schematic diagrams displayed in Fig 2c-f complement this sequence. Once a hole nucleates in the bubble film (Fig 2d), surface tension causes the film to rapidly retract and centripetal acceleration acts to destabilize the rim so that it forms ligaments and droplets. For the bubble shown, this retraction process occurs over a time of 150 microseconds, where each microsecond is a millionth of a second. The last image of the time series shows film drops launching into the surrounding air. Any particulates that became encapsulated into these film droplets, including all those encountered by the bubble on its journey through the water column, can be transported throughout the atmosphere by air currents.

Another source of droplets occurs after the bubble has ruptured (Fig 3b). The events occurring after the bubble ruptures is presented in the second time series of photographs. Here the time between photographs is one milliseconds, or 1/1000^th of a second. After the film covering the bubble has popped, the resulting cavity rapidly closes to minimize surface area. The liquid filling the cavity overshoots, creating an upward jet that can break up into vertically propelled droplets. These jet drops can also transport any nearby particulates, also including those scavenged by the bubble on its journey to the surface. Although both film and jet drops can vary in size, jet drops tend to be bigger.

Whether it is for the best or the worst, bubbles are ubiquitous in our everyday life. They can expose us to diseases and harmful chemicals, or tickle our palate with fresh scents and yeast aromas, such as those distinctly characterizing a glass of champagne. Bubbles are the messenger that can connect the depth of the waters to the air we breathe and illustrate the inherent interdependence and connectivity that we have with our surrounding environment.

The post The life of a bubble appeared first on OUPblog.

        

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Even before I had finished reading Bubble Trouble by Tom Percival to the kids I knew this was a book we were going to have LOTS of fun with.

Have you ever had great fun playing with a friend but discovered things have got out of control when you try to out-do each other? That what was a shared and enjoyable activity became something competitive and a little threatening?

Bubble Trouble explores exactly this scenario, with two best friends who like nothing more than blowing bubbles together. In their desire to blow the biggest bubble, they become very inventive but some skulduggery also sneaks in. Will their friendship survive their determination to outplay each other?

Percival’s lovely book thoughtfully and playfully explores the up- and downsides of competition and the value of teamwork. It also acknowledges that we don’t always learn from our mistakes straight away, something I haven’t seen often acknowledged in picture books. The “big issues” are hidden carefully in lots of delightfulness; the illustrations are soft and sweet, and there are lots and lots of flaps to play with. Percival has worked wonders with capturing that magic sheen of bubbles without resorting to foil or silver but rather just clever use of pastels and white.

A good-natured and honest exploration of some of the trials and tribulations of friendship, Bubble Trouble offers lots of room for discussion and a great excuse to play.

So yes, having shared Bubble Trouble lots of playing with bubbles was called for. We thought we’d try something different and so I taught the girls how to breath out bubbles, big and beautiful bubbles. Who wants to breath fire when you can breathe out bubbles?

We used this recipe to make our bubble mixture:

Once the bubble mixture was all stirred together, we left it for 24 hours. Everything I’ve read says that this stage is really important (though we haven’t checked what difference it makes ourselves).

To breathe out bubbles here’s what you need to do:

1. Dip your hands into a bowl of tap water.
2. Dip your hands into your bowl of bubble mixture. (The corn flour will probably have settled at the bottom of your mixture. This didn’t seem to be a problem)
3. Rub your palms together smoothly and slowly a couple of times.
4. Open out your hands to form a rough circle: Your fingertips and wrists/bottom of thumbs will remain touching each other, and you should see a film of bubble mixture form between your two hands.
5. Gently blow through the opening between your two hands…..
6. Gasp at your bubble blowing abilities!

You can also use this mixture to blow bubbles through a circle made using just your first finger and thumb (first make a fist, then slowly open out your finger/thumb before blowing), and also to make ENORMOUS bubbles using a home made bubble wand.

For the homemade bubble wand you’ll need two lengths of dowelling. Screw an eye screw into each end and then put a large loop of string between the two eyes. It’s helpful to add a small weight such as a threaded button or a washer onto on side of your string loop.

Dip your string into your bubble mixture (all the way, up to the start of the wooden rods), lift gently out and move the rods apart. You’ll see a film appear between the strings and then if you wave them from one side to the other you’ll create amazing bubble tunnels.

There’s nothing like a good bubble!

Whilst mixing up our bubble juice we listened to:

Other activities which you could pair with Bubble Trouble include:

What are your favourite books which feature bubbles?

Disclosure: We received a free review copy of Bubble Trouble from the publisher.

If like me you grew up (mostly) in the UK in the 70s and 80s and you’re asked to think of a famous witch from the canon of children’s literature, I’m fairly confident the name Meg would be one of the first to trip off your tongue.

Back in 1972 Meg and Mog arrived on the scene (in a flash of lightning, out of a cauldron, the wonderful result of a spell gone not quite according to plan, I like to think), the creation of Helen Nicoll and Jan Pieńkowski and they’ve been delighting children ever since. I loved their books when I was little and now my children share my laughter when we read the stories of crazy japes and spells gone wrong which come together to form the Meg and Mog series.

With Halloween not far off the timing couldn’t have been better for the release of the first new Meg and Mog book in four years. Meg Goes to Bed is a worthy addition to the collection. Although the story is perhaps not quite as satisfying as Meg at Sea, Mog’s Missing or Meg’s Car, many features that you would want to find in a quintessential Meg and Mog story are here to delight in.

There is an apparently simple scenario – Meg, Mog and Owl are hungry – but yet disaster still manages to strike. There’s a classically illustrated recipe for a spell, followed by the inevitably unintended results when the magic words are incanted. Meg’s catch phrase (“Oh dear, oh dear“), Mog and Owl’s nigh on obligatory crash landing and the idea that hard work and perseverance rather than the swish of a magic wand will get you what you need all add up to making this a book that my children were thrilled to read and that I was very pleased to add to our collection.

Pieńkowski’s bold, graphic design influenced illustrations, with their bright, sheer palette and tone are dramatic and exciting. In Meg Goes to Bed the articulation of the familiar characters, Meg, Mog and Owl is slightly less smooth than in earlier Meg and Mog books, but then I would not expect characters which have been drawn for almost 40 years to be identical today with their first incarnations. Indeed when I asked Jan about this as part of an interview I held with him (which will be published on Monday) he had this to say: “Change is inevitable… The Great Masters have “an Old Style”, perhaps humble illustrators are allowed to have one too!“.

An additional joy of reading Meg Goes to Bed was that it made a great early reader for M – in fact she has taken great pride in reading it to J. As M said, it’s a “real” book (rather than one written as an early reader), with engaging, familiar illustrations. Seeing M’s happiness at being able to read a brand new story from a s

New painting...more coming soon.

So you thought you used to play 2D games. If you had taken a look behind the screen, then you'd have seen this. The featured game is Bubble Bobble from Taito, a classic 8-bit video game for the arcades and home computers, released in 1986.

Like many other Sevensheaven images this image is available as a high-quality art print. Visit the Sevensheaven shop portal for more info.

by Katie Van Camppictures by Lincoln AgnewBalzer+Bray / HarperCollins 2009Here we have the promise of some truly bold retro graphics marred by a weak text with the faint whiff of celebrity, second-hand by-association celebrity at that.Late at night, while she should be sleeping, Harry sneaks out of bed and grabs his Bubble Blooper down, a 50s space gun that shoots large bloopy bubbles. The

From the moment I saw this cover, I was mesmerized.

Two children trudge up a hill and plant some seeds. The girl plants watermelon, and the boy seemingly plants top hats.

As they sleep beside the garden, something magical happens. The top hat seeds thrust up a twisted vine that is topped with gorgeous orange flowers. Out from an orange flower climbs a polar bear wearing a top hat.

From that top hat wondrous things emerge for the children with which to play. Monkeys with fuzzy arms and legs. Lion shaped bubbles. Breezes filled with sea creatures.

After the adventure, the children are put back to bed, the wonders go back into the hat, and though the vine stays, the bear and his hat do not.

Was it a dream?

Wordless, wonderful an absolutely beautiful, Wonder Bear was apparently inspired by a gummi bear. Tao Nyeu is certainly a gifted artist with a real sense of story. Under the dust jacket are pre-printed covers featuring our monkey friends and wonder bear himself (herself?). I am not a student of design, but I do know when folks get it right. Wonder Bear begs readers to go back time and time again to discover new wonders.

Delightful.

Here is my valentine piece for our mailer.


Happy Valentine's Day!

MARIGOLD AND THE FEATHER OF HOPE, THE JOURNEY BEGINS (Fairy Chronicles)
by J.H. Sweet
May 2007
Review copy compliments of the publisher

In the first book of the Fairy Chronicles, Beth’s dreaded visit to Aunt Evelyn’s takes a turn for the better when Beth learns she is a fairy. Marigold Fairy, to be exact.

The minute we got news of this book, I knew which of my fifth graders would be the first reader. I’ve seen her with other fairy books, and she took a spell book out to recess for weeks on end last fall. All of the characters in her writing have magical mystical powers and they go on epic quests.

Little did I know just how into fairies she is. She has read all of the Disney Fairies books, and owns several. She can recite the names, talents and adventures of all the Disney fairies. So it’s an understatement to say that she brought some background knowledge to her reading!

She was practically giddy with excitement when I showed her the book and asked her to read it in one night, if possible. (She managed in two.) She found one way that the Fairy Chronicles fairies differ from the Disney fairies: the fairies in the Fairy Chronicles are humans who can change back and forth from their fairy selves, while the Disney fairies are static fairies. Some of the fairies in both series have similar talents. There are Fairy Circles in both books, and the Fairy Chronicles has a handy fairy profile page which I missed, but she accessed several times when talking about the book to get the details right. She made a connection to GOSSAMER by Lois Lowry, and she was surprised and pleased to find the Tooth Fairy in the Fairy Chronicles.

Both of us were delighted by the Fairy Handbooks that automatically adjust the explanations and instructions so they are just right for that particular fairy and that particular age. (Magically leveled books! Hmm….) A Fairy starts with the First Fairy Handbook, moves to the Fortunate Fairy Handbook (for Fairies who are 10-12 years old and accident-prone), then the Formidable Fairy Handbook, and last of all, the Final Fairy Hand book.

What pleased my student most, however, was when I told her that she could read book two before me, and she could read it at whatever pace she chose, since she had read the first one so quickly to be able to give me her feedback!

Franki and her students loved it. She has lots of fairy readers in her class and they have a whole system of who gets the books next. Her students thought the illustrations were a bit like Spiderwick’s but in color. For Franki, it was like Bewitched—there could be a magical person living by her or...she could be a fairy and didn’t know it yet.