The Invisible Made Visible
Fluid dynamics is the branch of physics describing the flow of liquids. The motion of a liquid can be described as a laminar or a turbulent flow and the magnitude of that flow can be quantified by the Reynolds number.
In this case, bubbles move in a direction towards the upper right of the frame due to the presence of a pressure gradient. The fluid streaming around the bubbles and tailing off in their wake is smooth and laminar which of course makes sense in this low Reynolds number regime. The fluid is a mix of Zinc Sulphate, Sucrose and a drop of glycerol.
Otherwise invisible, the flow is made visible here through a technique called differential interference contrast. Another technique employed by fluid dynamists and physicists for making invisible flows visible is called Schlieren Imaging or ‘Shadowgraphy’.
This is the crystal film formed when a popular face cream is smeared out on a cool surface and allowed to dry at room temperature. There are two stages of crystallisation states for this chemical compound, with this being the first stage. The colour is a result of a property of the material called birefringence and other factors including the orientation of the molecules constituting the crystal and the optical path length through the crystal.
Autumn Come and Gone
It's Autumn in Northern Europe and the Sun’s radiance incident on the forest canopy is declining. The photosynthetic machinery within the trees foliage begins to break down and disintegrate, transforming into various shades of yellows, oranges and browns. Over time, they drop away from their parent trees and scatter the forest floor below. However, looks can be deceptive. These structures are not botanical in nature, but are crystallized organic compounds imaged under a microscope.
Building Blocks of Life (Series)
All life on Earth as we understand today is built from four types of building blocks.
One of these building blocks are proteins. Proteins in turn are composed of a long strand of amino acids arranged in a specific sequence.
Proteins are manufactured in ribosomes as instructed by a process called transcription and translation. Every protein consists of a specific sequence of amino acids which fold up into a functional protein.
Building Blocks of Life (Series)
Building Blocks of Life (Series)
Left: Vines of amino acids. Top: Sucrose Jewels. Bottom: A flower of dopamine.
The branched pattern that forms from a suspension of Creatine. The pattern forming self assembly process is called diffusion-limited-aggregation (DLA) wereby particles jittering about in the molecular storm of Brownian motion collide and adhere to one another in a completely random way.
A close-up image of a soap film showing lipid 'islands' floating not in an abyss, but on the thinnest film of supported by surface tension.
Scanning electron microscopy image showing a cross section of the lichen, Xanthoria parietina. Lichens are symbiotic associations of two organisms, namely a fungus which provides a secure haven for algal cells. The algal cells find a home embedded in the meshwork of hyphae which deliver essential water/nutrients around the system. The algal cells in return for security provide the fungas with food as a by-product of photosynthesis. The orange cups are called apothecia which release reproductive spores into the external environment, to be carried off by the wind and rain or passing insects.
This is a montage image of many images seamlessly blended together and digitally painted as realistically as possible.
Droplets of Dopamine rain down on the substrate.
Using scanning electron microscopy, this is a close up of the thallus and the hair like features called rhizomes of the lichen Physcia adscendens. The thallus can be seen with crystals here and there, coloured purple for contrast.
The stigma, yet to unfold, is encircled by pollen covered anthers of this common waste land flower, Geranium robertianum. The recently germinated pollen grains (sex cells) await to be transported to the female part of another Geranium of its kind. In a symbiotic event, a pollinating insect such as a bee will journey from flower to flower, collecting pollen granules and sugar-rich nectar, to ferry back to its hive. In effect, the bee will inadvertingly carry the sex cells to other Geranium robertianum flowers where the majestic dance of life will continue once again.
Night Sky on Planet Acetaminophen.
A glorious night sky reveals itself on a frosty winters night on planet Acetaminophen. This image is actually a sliver of a thin film of acetaminophen, commonly known as Paracetamol, imaged on a microscope configured for polarised light. The stars in the background are just out water droplets that lie in a different focal plane. (Submitted to Pubmed Image competition Sept 2017)
Verbascum nigrum, commonly known as Mullein
Physcia adscendens is a commonly found on trees in nitrogen-rich areas. It is also found on limestone outcrops and cemetery headstones. Its name, 'adscendens ' refers to the long rhizines that arise from the underside and curl upwards. The grey colour of the thallus is due to the pigment, atranorin. On close inspection, notice green patches here and there on the leafy thallus. These green patches are colonies of cyanobacteria.
This a scanning electron microscopy montage comprising of many indiviual images which have been seamlessly blended together and digitally painted as realistically as possible.
The wild flower, Autumn Hawkbit, is a species of Dandelion in the genus, Taraxacum which is a member of the family, Asteraceae. The flower grows as a weed all across Europe and North America and blossoms in the Autumn time. The flower is the reproductive organ of a plant and in the case of Dandelion, it is a composite of many small flowers called florets. A pair of Dandelion pollen grains can be seen adhered to the cells comprising the style region of the floret. Pollen grains are the sexual seeds at the heart of the reproductive cycle. They contain the plants sperm and its food source. Once a pollen grain is transferred to the stigma of another flower of the same kind, by the beetles that inhabit the flower or bees for example, sperm will awaken from dormancy and the process of pollination can begin.
A single grain of pollen from the Yarrow flower as imaged using a scanning electron microscope. The image, originally monochrome, was artificially coloured as realistically as possible. The pollen grain is seen adhered to the peduncle region of the wild flower, and has a sporopollenin exine casing covered with many spikes whose purpose may be to latch on to passing insects and animals, like velcro. Pollen grains come in many unique shapes and forms depending on the plant from which they originate.
When a thin birefringent crystalline film is viewed under a polarised light microscope, a dazzling array of colours is revealed. The coloured pattern arises from a highly complex interaction between polarised light and the crystalline lattice. Lines of similar colour arise due to contours of equal thickness or integer multiples of thickness.
Close-up shot of Geranium robertianum showing the stamens and style tipped with the reproductive organs. The anthers are peppered in yellow pollen grains from which they This is a photograph taken through an optical microscope of Herb Robert. Notice the pollen grains covering the anthers and the cells of the petals like little glass beads.
Acquired with a home built optical microscope, the top image shows the front end of the insects visual system. Flies, being agile seeing creatures are able to navigate swiftly through the most unpredictable environments. Flies view the world through their two prominent panoramic compound eyes. Each compound eye consists of a mosaic of facet lenslets and an underlying layer of photoreceptor cells forming the retinal membrane.
Collected from the lake at UCD, a family of Daphnia: Mammy, Daddy, Baby and Teenager encrusted with acne (not really, single celled alga have latched onto this little one perhaps in some symbiotic affair).