26 Aug 2007

Zooplankton move to the moon's tune - life - 08 July 2007 - New Scientist

NewScientist.com news service

How do ocean animals that live below the depth to which moonlight penetrates migrate in phase with the moon?

Hans van Haren of the Royal Netherlands Institute for Sea Research in Den Burg used sonar to track zooplankton movement over 18 months. They migrate up and down the water column on daily and seasonal cycles, and van Haren also identified a strong monthly movement that coincided with lunar cycles (Geophysical Research Letters, vol 34, p L12603). But the zooplankton remain at or below 800 metres, while moonlight penetrates no deeper than 150 metres. "This has nothing to do with physical processes," say van Haren, "but a biochemical clock could explain it."

Other studies have shown that zooplankton kept in the dark can retain light-induced biorhythms for several weeks. Van Haren's work suggests that biorhythms can be preserved for far longer.

Zooplankton move to the moon's tune - life - 08 July 2007 - New Scientist

20 Aug 2007

Conquest Of Land Began In Shark Genome

Science Daily

Scientists at the University of Florida have identified genetic activity in sharks required for the development of hands, feet, fingers and toes in limbed animals. The finding shows what was thought to be a relatively recent evolutionary innovation existed eons earlier than previously believed, potentially providing insight for scientists seeking ways to cure human birth defects.

Sharks (like this Great White off the coast of Guadalupe Island, Mexico) have the recipe for fingers in their genetic cookbook, researchers have found. (Credit: iStockphoto/Keith Flood)

When the first four-legged animals sprouted fingers and toes, they took an ancient genetic recipe and simply extended the cooking time, say University of Florida scientists writing in Wednesday's issue of the journal PLoS One.

Even sharks -- which have existed for more than half a billion years -- have the recipe for fingers in their genetic cookbook -- not to eat them, but to grow them.

While studying the mechanisms of development in shark embryos, UF scientists identified a spurt of genetic activity that is required for digit development in limbed animals.

ScienceDaily: Conquest Of Land Began In Shark Genome

8 Aug 2007

MARES introduces the NEMO EXCEL dive computer

Next generation NEMO EXCEL builds on popular advanced dive computer in a major way.

Building on the success of the original NEMO, the NEMO EXCEL is a natural evolution using upgraded components for a tougher computer with a more technical look. A larger segmented display and flat, recessed mineral glass provides improved contrast at wider viewing angles. The non-reflective mineral glass is scratch resistant, shock proof and tempered for better durability and visibility in all conditions. Large textured buttons make NEMO EXCEL’s 4-button intuitive menu operation even easier than its predecessor. A pre-shaped ergonomic strap allows the NEMO EXCEL to fit more comfortably on the wrist.

NEMO EXCEL has 4 Dive Modes: Air, Nitrox, Bottom Timer and special Free Dive functions. Equipped with the most advanced RGBM Mares-Wienke algorithm, considerably lowering the risks associated with the formation of micro-bubbles by introducing deep stops. An active, timer-controlled display light is easily turned on by the pressing of a single button. Strap extension is included. Watch functions include dual time zones, alarm clock function, stop watch and calendar.

“The new design of the NEMO EXCEL is the perfect integration of an advanced featured dive computer and stylish wrist watch. It is ideal for below and above the surface” states Phil Mintz, Vice President of Diving, MARES USA.

Recently tested by the world’s most widely published underwater photographer Stephen Frink; Stephen states:

“I just came up from my first dive with the MARES NEMO EXCEL. I loved the ease of navigation and general ergonomics. The screen is very informative, logical, and easy to read. It is small and handsome enough for daily wear while on a dive trip, yet packs an informational punch while underwater”.

The NEMO EXCEL has a suggested retail of $600.00 and will be arriving at MARES dealers in early August 2007.

For additional information on this product and the complete line of Mares products for 2007 contact your MARES District Sales Manager, Customer Service or go to www.mares.com for your nearest Authorized MARES Dealer.

6 Aug 2007

Olympus Stylus 770SW 7.1MP Digital Camer

Salt water spray has claimed two of my previous cameras so when I read about this camera and the Pentax Option W30 I decided one of the two would be a very valuable investment. The next question was deciding which one to buy.

The Pentax is a superior camera. Colors are more saturated, and it has lower noise higher up the ISO range. Also, the Pentax produces videos that are 30FPS (the Olymmpus only goes up to 15FPS) which is a huge advantage. Also, the Pentax uses SD cards, which are available at higher density and faster speed.

The Olympus, on the other hand, is much more bulletproof.

First of all, it will survive down to 30' whereas the Pentax is limited to 10. I wanted a camera that could survive light snorkeling. I routinely breath-hold dive to 12'-15' and I'd hate to have a camera on me that I would worry about. With the Olympus I just do whatever I want.

Second, the Olympus is crush proof. I can slap the thing in my backpocket and sit on it and not break it (I weigh about 190#). I can get on my boat, throw the thing on the deck with the rest of my gear, and watch it bounce around unharmed. The Pentax is just not that strong.

In the end, since I already have a camera that takes brilliant, vivid pictures with great resolution and also takes great video (a Canon SD550) I decided rugged was more important than marginally better optical rendition. I figured the Olympus would take acceptably good pictures and I went with the Olympus.

I'm not disappointed, but I'm not thrilled.

The camera is every bit as waterproof and bulletproof as is claimed. I've slapped it around, thrown it, had it around the boat, seawater, sun, kids, and it's just fine. I can take this camera with me on the boat, take it with me swimming and snorkeling, and it will work when I'll want it. A camera is only useful when you have it and I'm not afraid to have the Olympus with me at all times in any environment.

Having said that, the picture quality stinks, I suspect as a result of the lens design dictated by the water resistant qualities of the camera. In bright sunlight, with the ISO set to 100 (and even up to 200 it's not bad) there is no significant noise. On the other hand, the colors appear washed out and dull compared to similar pictures taken with the Canon. Its resolving power is also inferior to the Canon and there's no question but that I'll continue to use my Canon in environments that are friendly to it (like, no salt water spray risk). On the other hand, since I can't take my Canon everywhere, I love having this camera; I recently went to see America's cup practices in Valencia and I'm happy to say I have a couple of shots of Alinghi that will make decent poster prints. They'd look better taken with my Canon but....right, I would not have taken my Canon in that environment, so...

Focusing delay is very short, as is shutter delay. If you prefocus, the shutter delay is non-existent. Without prefocus, it's less than a second: not bad. On the other hand, shot to shot delay is annoyingly long, a couple seconds at full resolution.

Image compression is average. In the best quality mode you can still see some compression artifacts but the average person will not notice. If you do know what to look for, you'll find it annoying but not a deal-breaker.

I bought a 2Gb H Xd card, and it's pretty fast but not as good as high speed SD. Also, it's nowhere near the density that SD has reached, but 2Gb will go a pretty long way.

In short: buy this camera to take it in places where other cameras fear to go. Don't buy this camera if all you want is great pictures for the backyard or the trip to Disneyland.

Ah, almost forgot. Buy a large styrofoam float and attach it to the lanyard. If you lose the camera over the side of your boat, it's nice to be able to go back and pick it up.

Variation Parent: Olympus Stylus 770SW 7.1MP Digital Camera with Dual Image Stabilized 3x Optical Zoom (Silver)