The MRI scanner measures this signal difference and displays the activity as a colored area (Figure 1). Diffusion Tensor Imaging (DTI) is a technique that detects how water travels along the white matter tracts in the brain (Figure 2). White-matter tracts connect different parts of the brain and must be protected during surgery. A dye (contrast agent) may be injected into your blood stream.
This fascinating arthropod, also known as the water spider, is quite similar to other spiders in that it breaths air, although it does it in a much more creative way. These spiders spin a web cocoon of silk which they then fill up with air creating a bubble that they can take with them underwater. And due to a mostly sedentary life this spider is able to make the most of its oxygen only needing to come up about once a day or even less to replenish its air supply.
Huntsman spiders(Sparassidae family)Huntsman spiders are widespread in Australia. They are famous for being the bit (up to 15cm leg-span) scary, hairy, black spiders bolting out from behind the curtains. In reality, they are reluctant to bite and more likely to run away when approached and their venom isn't considered dangerous for humans. Their danger comes more from causing accidents by the terrified drivers who react to a huntsman jumping out from behind the sun visor or dashboard of a car when it's in motion. Despite their intimidating size, huntsman spiders can be an ally in the house; they help with pest-control by eating smaller insects.