The Philippine Online Chronicles

Bullet-stopping spider silk, ultrasonic treatments for male birth control, and beautiful views of our world from space led science headlines last week.

Spider-silk skin stops a bullet

Spider-silk has long been known to be nature's toughest fiber, with the bark spider's silk being 10 times stronger than Kevlar, but a recent proof of concept further reinforces the potential of the material in engineering.

A futuristic tissue designed by artist Jalila Essaïdi (along with an international team of scientists) was demonstrated to be able to stop a bullet moving at half-speed or around 166 m/s; when the bullet was at the peak 329 m/s, the skin broke.

Potential applications of industrial spider silk include medicine, with more secure sutures, and personal defense, which currently adheres to a proportional relationship between weight and protection.

Ultrasound may be new form of male contraception

Scientists at the University of North Carolina at Chapel Hill recently announced findings where rats were rendered infertile using commonly available ultrasound equipment.

"Our noninvasive ultrasound treatment reduced sperm reserves in rats far below levels normally seen in fertile men," study researcher James Tsuruta said in a statement.

The sperm concentration of rats (animals which are much more fertile than humans) in the experiment was decreased to 3,000 motile sperm per milliliter. In the rats, this number would still allow them to reproduce. In the case of humans, where a low sperm count is defined as 15 million sperm per milliliter and vasectomies decrease sperm concentration to 3 million sperm per milliliter, these findings become particularly significant.

However, more research must be done to ensure the treatment's safety before it can be considered a male birth control method. The study was published yesterday in the journal Reproductive Biology and Endocrinology.

New satellite takes beautiful Earth image

NASA released a high-resolution image of Earth, taken with the new satellite Suomi NPP, earlier this month.

North and Central America take center stage in the picture, which was compiled by the satellite over a series of pictures it took over 4th January. The photo has been nicknamed “Blue Marble 2012”, recalling the famous photo of Earth taken by the Apollo 17 crew in 1972.

Suomi NPP, which observes Earth, aims to collect data on both long-term climate change and short-term weather changes. A high-resolution copy of the photograph (8,000 by 8,000 pixels at 16.5 MB) can be downloaded here.