Implanted devices that can wrap around tissues
Researchers have created electronic devices that become soft when implanted inside the body and can grip 3-D objects, such as large tissues, nerves and blood vessels.Scientists from The University of Texas at Dallas and the University of Tokyo said the biologically adaptive, flexible transistors might one day help doctors learn more about what is happening inside the body, and stimulate the body fortreatments.The research is one of the first demonstrations of transistors that can change shape and maintain their electronic properties after they are implanted in the body, said Jonathan Reeder, a UT Dallas graduate student in materials science and engineering, and lead author of the work.“You need the device to be stiff at room temperature so the surgeon can implant the device, but soft and flexible enough to wrap around 3-D objects so the body can behave exactly as it would without the device.“By putting electronics on shape-changing and softening polymers, we can do just that,” Reeder said.Shape memory polymers developed by Dr Walter Voit, assistant professor of materials science and engineering and mechanical engineering and an author of the paper, are key to enabling the technology.The polymers respond to the body’s environment and become less rigid when they are implanted. In addition to the polymers, the electronic devices are built with layers that include thin, flexible electronic foils first characterised by a group including Reeder.The Voit and Reeder team fabricated the devices with an organic semiconductor but used adapted techniques normally applied to create silicon electronics, cutting the cost of the devices.The rigid devices become soft when heated. Outside the body, the device is primed for the position it will take inside the body, researchers said.During testing, researchers used heat to deploy the device around a cylinder as small as 2.25 mm in diameter, and implanted the device in rats. After implantation, the device had morphed with the living tissue while maintaining excellent electronic properties.
No chameleons in dark energy?
Particle physics always conjures up images of very high-energy experiments, particle accelerators etc. A recent study — a table-top experiment with low-energy neutrons — shatters this image and introduces a low-energy technique to probe gravity, dark energy and dark matter.
In a paper published in April, in Physical Review Letters, Jenke et al, led by Hartmut Abele of Technical University of Vienna, Austria, report that ultracold neutrons can be used in “gravity resonance spectroscopy” to yield constraints on the properties of dark energy and dark matter.
These measurements, in fact, disprove the existence of the hypothetical “quintessence” particles which form one explanation for dark energy, at this level of accuracy. But the search for these particles will continue as it is possible that a greater level of accuracy is needed.
In the experiment, conducted at the Institut Laue-Langevin, Grenoble, France, the researchers confined ultracold neutrons between two neutron-mirrors. This system along with the earth’s gravitational field closely mimics the famous “particle in a box” of quantum mechanics. Varying the separation between the walls periodically caused the energy levels of the system to oscillate and the confined neutrons to make transitions, whose values can be measured as well as calculated.
This experiment measures the neutrons’ coupling to gravity very accurately, so that it can actually probe interactions with the very weakly interacting hypothetical particle of dark matter, the axion, and the chameleon field, which is a name for the proposed source of dark energy.
To digress briefly, dark energy is a proposed explanation for the accelerated expansion of the universe and dark matter is needed to describe the rotation curves of galaxies and the large scale structure of the universe. However the properties of these entities have not been understood well at all. The axion is expected to couple to the spin of the neutron and thereby, it would affect the neutrons’ behaviour slightly.
Jenke et al first polarise the neutrons and then pass them through the cavity and then measure their transition frequencies again. The comparison of these experimentally measured values to the theoretical values puts constraints on the coupling constant of the interaction (a measure of the strength of the interaction with the axion field).
“Our experiment now sets much better limits on this strength parameter, so that the ‘allowed’ parameter space (allowed means that it does not contradict observations) gets much smaller,” Says Tobias Jenke of the collaboration in an email.
IQ-boosting gene found
People who have a variant of a longevity gene have improved brain skills such as thinking, learning and memory. Researchers found that increasing levels of the gene, called KLOTHO, in mice made them smarter, possibly by increasing the strength of connections between nerve cells in the brain.
The study was published in Cell Reports. Those who have one copy of a variant of the KLOTHO gene, called KL-VS, tend to live longer and have lower chances of suffering a stroke whereas those who have two copies may live shorter lives and have a higher risk of stroke. The study also found that those with one copy performed better on cognitive tests regardless of age, sex or the presence of the apolipoprotein 4 gene, the main genetic risk factor for Alzheimer’s disease. — PTI
World’s oldest sperm discovered in Australia
Scientists have discovered the world’s oldest and best-preserved sperm from tiny shrimps, measuring a massive 1.3 millimetres and dating back to 17 million years in Australia.Preserved giant sperm from shrimps were found at the Riversleigh World Heritage Fossil Site in Queensland and are the oldest fossilised sperm ever found in the geological record, researchers said.
The shrimps lived in a pool in an ancient cave inhabited by thousands of bats, and the presence of bat droppings in the water could help explain the almost perfect preservation of the fossil crustaceans.The giant sperm are thought to have been longer than the male’s entire body, but are tightly coiled up inside the sexual organs of the fossilised freshwater crustaceans, which are known as ostracods.“These are the oldest fossilised sperm ever found in the geological record,” said Professor Mike Archer, from the University of New South Wales (UNSW), who has been excavating at Riversleigh for more than 35 years.“The discovery of fossil sperm, complete with sperm nuclei, was totally unexpected,” said Archer.A UNSW research team led by Archer, Associate Professor Suzanne Hand and Henk Godthelp collected the fossil ostracods from Bitesantennary Site at Riversleigh in 1988.They were sent to John Neil, a specialist ostracod researcher at La Trobe University, who realised they contained fossilised soft tissues.He drew this to the attention of European specialists, including the lead author on the research paper, Dr Renate Matzke-Karasz, from Ludwig Maximilian University of Munich, who examined the specimens with Dr Paul Tafforeau at the European Synchrotron Radiation Facility in Grenoble, France.The microscopic study revealed the fossils contain the preserved internal organs of the ostracods, including their sexual organs.Within these are the almost perfectly preserved giant sperm cells, and within them, the nuclei that once contained the animals’ chromosomes and DNA.Also preserved are the Zenker organs – chitinous-muscular pumps used to transfer the giant sperm to the female. The researchers estimate the fossil sperm are about 1.3 millimetres long, about the same length or slightly longer than the ostracod itself.“About 17 million years ago, Bitesantennary Site was a cave in the middle of a vast biologically diverse rainforest.Tiny ostracods thrived in a pool of water in the cave that was continually enriched by the droppings of thousands of bats,” said Archer.The bats could have played a role in the extraordinary preservation of the ostracod sperm cells, UNSW’s Associate Professor Suzanne Hand said.The steady rain of poo from thousands of bats in the cave would have led to high levels of phosphorus in the water, which could have aided mineralisation of the soft tissues.The study was published in the journal Proceedings of the Royal Society B.
Court upholds ‘right to be forgotten’ by Google
The European court, in an important test of the “right to be forgotten,” ruled on Tuesday that Google must amend some of its search results at the request of ordinary people when they show links to outdated, irrelevant information.
In an advisory judgment stemming from a Spanish case, The Court of Justice of the European Union said Google and other search engines do have control of individuals’ private information, given that they sometimes compile and present links to it in a systematic way.
The court found that under European law, individuals have a right to control over their private data, especially if they are not public figures. If they want irrelevant or wrong personal information about themselves “forgotten” from search engine results, they have the right to request it even if the information was legally published.
People “may address such a request directly to the operator of the search engine ... which must then duly examine its merits,” the ruling said.
Whether or not the request should be granted will depend “on the nature of the information in question and its sensitivity for the data subject’s private life and on the interest of the public in having that information, an interest which may vary,” it said.
Google must remove links to pages containing the information from results “unless there are particular reasons, such as the role played by the data subject in public life, justifying a preponderant interest of the public in having access to the information when such a search is made,” the court said.
Google could not immediately be reached for comment.
It had argued that it doesn’t control personal data, it just offers links to information already freely and legally available on the Internet. It had also argued that it should not be forced to play the role of censor, especially when it offers links to information that was legally published.
The case was referred to the European court by Spain’s appeal court, the Audiencia Nacional, which has fielded 200 such complaints.
The leading case was from a Spaniard named Mario Costeja who said that when his name was Googled it threw up references to an advertisement for a property auction related to an unpaid Social Welfare debt. Mr. Costeja and the agency argued that the debt had long been settled and that the reference should be removed.
The ad had originally appeared in a Spanish newspaper and was tracked by Google’s robots when the newspaper digitalized its archive.
India ranks third in contribution to global malicious activity: Symantec
Alarming as it may sound, according to a report by data security solutions provider Symantec, India ranks as the third highest source of overall malicious activity globally.
Terming India ‘A Key Threat Frontier’, the annual internet security threat report said 5.1 per cent of all malicious cyber activities in the world originated from India in 2013. At the top spot was the US (20.33 per cent), followed by China (9.93 per cent).
India is followed by Netherlands (3.52 per cent), Germany (3.26 per cent), Russia (2.63 per cent), UK (2.58 per cent), Brazil (2.53 per cent), Taiwan (2.45 per cent), and Italy (2.35 per cent), as per the report.