Category Archives: Special Senses

Kepler Optica

A plate from Johannes Kepler’s Ad Vitellionem Paralipomena, quibus Astronomiae Pars Optica (1604), illustrating the structure of eyes.

Kepler_Optica

Image from wikimedia commons (link)

The Renaissance astronomer and astrologer Johannes Kepler is best known for his discovery of the three principles of planetary motion, by which he clarified the spatial organization of the solar system. Moreover, he founded modern optics by presenting the earliest correct explanation of how human beings see. He was the first to set forth accurately what happens to light after it enters a telescope, and he designed a particular form of that instrument. His ideas provided a transition from the ancient geometrical description of the heavens to modern dynamical astronomy, into which he introduced the concept of physical force.

(from Univ Oregon – link)

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Retinal Implant

Recently, an electronic chip measuring 3mm square was implanted behind the retina of patients left blind by retinitis pigmentosa.

Blind people have described smiles on friendly faces, the food on their plates, and household objects from telephones to dustbins, after surgeons fitted them with electronic chips to partially restore their vision.

Image from theverge.com (link). X-ray of a patient fitted with the retinal implant. A dial on the outside of the head controls brightness levels. Photograph: Robert MacLaren/Oxford Eye Hospital

Results from the first eight patients to enrol in a clinical trial of the retinal implants show that five found the chips improved their eyesight enough to be useful in everyday life.

All those involved – men and women aged 35 to 62 – had lost their sight to retinitis pigmentosa, a hereditary disease that destroys the light-sensitive cells in the eye. The chip stands in for the defunct cells by detecting light rays and converting them into electrical pulses, which are sent along the optic nerve to the brain.

Each patient spent up to 10 hours in surgery to have the 3mm by 3mm chip implanted in one eye. The chip is studded with 1,500 light-sensitive elements that pick up light falling on the macula, the most light-sensitive part of the retina. (from the guardian – link)

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Obesity

Obesity is a medical condition in which excess body fat has accumulated to the extent that it may have an adverse effect on health, leading to reduced life expectancy and/or increased health problems. People are considered obese when their body mass index (BMI), a measurement obtained by dividing a person’s weight in kilograms by the square of the person’s height in meters, exceeds 30 kg/m2  (adapted from wikipedia)

Roughly one-third of U.S. adults are obese, with some researchers suggesting that percentage might climb to 44 percent by 2030. (from UCSD health sciences -link)

Image from UCSD health sciences tumblr (link)

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Vallate Papillae

The circumvallate papillae (or vallate papillae) are dome-shaped structures on the human tongue that vary in number from eight to twelve. (from wikipedia)

NYU virtual microscopy (link). Vallate papillae

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