The eyes have it
enewable energy sources are a hot topic right now and have been listed as one of the most efficient tools we have in the fight against climate change.
Here in New Zealand, hydropower, geothermal and wind energy are the primary sources of our renewable power, however another that could soon be added to the list is human tears.
This is thanks to new research published this week in the journal Applied Physics Letters which discovered that a protein present in our tears, saliva and milk can also be used to generate electricity.
The protein, called lysozyme, was discovered by Alexander Fleming in 1922. He found it showed antibacterial activity when tested on nasal mucus bacteria donated from a patient suffering with a head cold.
Six years later, Fleming went on to discover the antibiotic penicillin, which has saved millions of lives, but lysozyme continued to have historical significance as the first enzyme structure to have been solved and fully mapped in three dimensions using a technique called x- ray diffraction.
The study this week found that when crystallised, lysozyme proteins display piezoelectricity — the process of converting mechanical energy into electrical energy, meaning that when you squeeze a piezoelectric material it can create an electrical field, and in reverse if you apply an electric field the material can change shape.
You have probably used piezoelectricity a few times already today. For the watch wearers amongst us, it’s what keeps a quartz watch on time; the microphone in your computer will use piezoelectricity to turn the sound energy from your voice into electrical signals that your computer can process, and if you have a gas stove at home, the clicking sound from the ignition button is It might be lingering bashfully on the icy outer edges of our solar system, hiding in the dark, but subtly pulling strings behind the scenes. It’s a possible “Planet Nine” — a world perhaps 10 times the mass of Earth and 20 times further from the sun than Neptune.
The signs so far are indirect, but add up to a compelling case nonetheless.
One of its most dedicated trackers, in fact, says it’s now harder to imagine our solar system without a missing Planet Nine than with one.
“There are now five different lines of observational evidence pointing to the existence of Planet Nine,” said Konstantin Batygin, a planetary astrophysicist at Caltech in Pasadena, California, whose team may be closing in on the heavenly body. coming from a piezoelectric material being squeezed and creating an electrical spark.
Quartz is the most commonly used piezoelectric material, but many other materials with an asymmetric atomic structure can also exhibit piezoelectric properties including topaz, sucrose and lead titanate.
In addition to natural materials,
“If you were to remove this explanation and imagine Planet Nine does not exist, then you generate more problems than you solve.
“All of a sudden, you have five different puzzles, and you must come up with five different theories to explain them.”
Batygin and his co- author on a new study, Caltech astronomer Mike Brown, described the first three clues last year, and two more biological materials including wood, bone and tendons are also piezoelectric. The challenge is that these biological materials are made up of fibrous protein structures which make them difficult to process and crystallise and unsuitable for commercial use.
With their globular structure, the lysozyme proteins are much easier to have since emerged. One suggested Planet Nine could have tilted the planets of our solar system during the last 4.5 billion years, explaining a longstanding mystery.
The other involved objects from the Kuiper Belt that orbit in the opposite direction to everything else in the solar system. “No other model can explain the weirdness of these high- inclination orbits,” Batygin said.
“It turns out that Planet Nine provides a natural avenue for their generation.”
The remaining step, of course, is to find Planet Nine itself. If discovered, it would be a homecoming of sorts, or at least a family reunion.
Over the past 20 years, surveys of planets around other stars in our galaxy have found the most common types to be “super Earths” and their somewhat larger cousins — bigger than Earth but smaller than Neptune. Yet these common, gardenvariety planets are conspicuously absent from our solar system. Weighing in at roughly 10 times Earth’s mass, the proposed Planet Nine would make a good fit. crystallise as a thin film just by evaporating on to a glass slide.
The researchers used an actuator to apply pressure to squash the film and measured the voltage using electrodes. Their results found the lysozyme protein crystals produced the same order of magnitude of piezoelectricity as the standard go- to material quartz. While it may sound enough to make women experiencing the nausea of early pregnancy scoff, researchers have suggested morning sickness can take a toll on expectant dads.
New research out of Australia’s Edith Cowan University examined the experience of 300 expectant couples and found more support was needed for the partners of women experiencing nausea and vomiting during pregnancy. The study aimed to gauge expectant fathers’ awareness of what their partners were going through, and the affect it had on the dads themselves.
The study found 82 per cent of fathers were aware that their partner experienced morning sickness. Of these, 20 per cent reported no nausea or vomiting, mild 30 per cent, moderate 37 per cent and severe 13 per cent. The partners of all 11 women formally diagnosed with hyperemesis gravidarum, reported the nausea and vomiting was severe.
Researchers asked expectant fathers about their partners’ condition and their own mental health and found a significant known as Nanogirl, is an Auckland University nanotechnologist who is passionate about getting Kiwis hooked on science. Tweet her your science questions
Although quartz is an abundant material, the advantage of the lysozyme crystals could be their increased biocompatibility as they are from a biological source.
This could make them safe to use inside the body and has the potential to open up new applications in energy harvesting for medical devices such as pacemakers and biological pumps.
Alternatively, with its known antibacterial activity, the lysozyme crystal could be evaporated on to surfaces and used as a biocompatible antimicrobial coating for medical instruments and devices.
Although still in the preliminary stages of research, there is no need to panic about human tear increase in dads’ anxiety levels.
Although there was some support available for pregnant women during pregnancy, the fathers were often left to fend for themselves, lead researcher Julie Sartori said.
“The study showed that in families where the mother experienced moderate or severe morning sickness, fathers reported much higher levels of anxiety.” That anxiety was linked to five main factors — disruption to work, feelings of frustration and helplessness, concern over depression in their partner, worry for the developing baby, and a “sense of being manipulated”. also harvesting becoming the next electricity generating industry. In addition to tears and saliva, lysozyme is also found in the egg whites of birds, and powdered hen egg whites are already a commercial source of the protein. Having said that, a future where you have to squeeze your tears to charge your smartphone could possibly lead to a resurgence of romantic comedy movies. A new study has drawn a link between night shift and obesity. Researchers from the Chinese University of Hong Kong analysed data from 28 previous studies to find that night shift work was connected to a 29 per cent increase in a worker’s chance of becoming overweight or obese.
The weight was mostly centred around the worker’s stomachs, say the scientists, and mostly affected those who worked nights permanently, rather than those who worked rotating shifts. “Globally, nearly 0.7 billion workers are engaged in a shift work pattern,” said the study’s senior author, Dr Lap Ah Tse.
“Our study revealed that much of the obesity and overweight among shift workers is attributable to such a job nature.
“Obesity has been evident to be positively associated with several adverse health outcomes, such as breast cancer, cardiovascular diseases.” The researchers suggest adjusting work schedules to avoid extended exposure to long- term night work could lighten the load, literally.
science writer Jamie Morton: @ jamienzherald
Can night shift make you fat?