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Mucus Cocoons Protect Fish from Parasites

Just as some peoplemust sleep with mosquito nets to ward off the bloodsuckers, coral reef fishapparently spin cocoons of mucus before slumbering to keep away bitingparasites, scientists find.

Coral reef fishessuch asand wrasses sleep soundly in mucus cocoonsthat have long fascinated recreational scuba divers and are often a mainattraction on night dives. Surprisingly, until now, no experimental studies hadexamined their function. []

Past observationalstudies have suggested these gooey blankets, which are secreted from thefishes' mouths, somewhat protect fish from nocturnal predators such as morayeels. However, researchers also found many cocooned fish were still eaten.

Fishy mosquito nets

To find out whythese cocoons are created, scientists concentrated on parasitic crustaceansknown as gnathiid isopods (tiny shrimp-like creatures), which feed on the bloodof fish. During the day, parrotfish seek outto remove these "marinemosquitoes," explained researcher Alexandra Grutter, a marine biologist atthe University of Queensland in Australia.

For the study,researchers focused on the bulletheadparrotfish (Chlorurus sordidus). Each parrotfish has to be caughtseparately by a scuba diver using a large 6-foot-by-45-foot (1.8 meter by 13.7meter) net; swimming underwater with a rolled-up net takes stamina, Gruttersaid. Also, "parrotfish are extremely slippery so getting them from a handnet to a catch bag is very tricky," Grutter added. "Parrotfish alsohave a mouth shaped like a beak, hence their name, so you want to avoidsticking your finger in their mouth when putting them in a bag."

Back at the lab, theresearchers compared fish coated with mucus with ones the researchers gentlypushed out of their cocoons without disturbing their snooze. The slumberingfish were then exposed to the parasites for 4.5 hours.

The scientists foundthat nearly 95 percent of the fish without the cocoons were attacked, comparedwith just 10 percent of those coated in mucus.

"At night, whencleaner fish sleep, mucus cocoons act like 'mosquito nets,' allowing fish tosleep safely without being constantly bitten, a phenomenon new toscience," Grutter said.

Eating mucus

The researchersestimated crafting these cocoons takes up 2.5 percent of the fish's dailyenergy.

"The amount ofeffort that goes into building these cocoons, which requires fish to havedeveloped very large glands about the size of [a] quarter to produce thecocoons, is extraordinary," Grutter said. "Parasites must exert anenormous pressure on these fish in order for the fish to have evolved such aspecific way of avoiding the parasites."

The parasites mightnot simply only wound the fish. "These parasites have been implicated intransmitting a blood parasite, which resembles malaria," Grutterexplained.

It remains uncertainexactly how the cocoons protect the fish. "Are they a physical and/orchemical barrier, or do the cocoons prevent the parasites from detecting fishby blocking ?" Grutter asked. "What other organisms aredeterred by the cocoons? Research in the wild would be interesting, but this isinherently dangerous due to the dangers of working underwater in the dark andother nocturnal predators of humans, such as sharks."

It is also an openquestion as to whether the fish can recoup part of their investment by eatingthe cocoons.

"I haveobserved on occasion a fish at dawn with what appeared to be mucus stuffed inits mouth," Grutter told LiveScience. "I have observed another fishthat produces cocoons, the cleaner fish Labroides dimidiatus, peckingaway at its old cocoons in the morning."

The scientistsdetailed their findings Nov. 17 in the journal Biology Letters.

The 10 Most Diabolical and DisgustingParasitesMind-Controlling Parasites Date Back Millionsof YearsOriginal Story: chronicles the daily advances and innovations made in science and technology. We take on the misconceptions that often pop up around scientific discoveries and deliver short, provocative explanations with a certain wit and style. Check out our science ,and .to debate hot-button issues like stem cells, climate change and evolution. You can also sign up for free , register forand get cool gadgets at the .

'Decision Points': What George W. Bush's Memoir Reveals

Early on in his newly released memoir, George W. Bush writes with great credibility, and a welcome absence of histrionics, about his slow-motion turn toward faith. There was no fiery epiphany. There was a growing comfort with the calming release of prayer, a gradual appreciation of the moral truths contained in the Bible. There were doubts too. "If you haven't doubted, you probably haven't thought very hard about what you believe," he writes. And that principle is very much in evidence when he makes the first major decision of his presidency, in favor of federal funding for research on existing stem-cell lines but not for raiding frozen embryos - potential lives, he believes - to harvest their cells. To reach that decision, Bush conducted a White House seminar that included talks with advocates, brilliant ones, on all sides of the issue. "The conversations fascinated me," he writes. "The more I learned, the more questions I had." Whatever you think of his policy, the process was impeccable.

I mention this not only because it reveals Bush at his best but because it was so much at variance with the rest of his presidency.

The presidential memoir is among the more dreadful of literary forms. Most of them are far too long, and suffocating for the heavy woolen tone of false modesty that swaddles the egomania at the heart of the matter. They are defensive, evasive and stiff. Bush's effort is all that, but better than most. It reads well. The anecdotes are occasionally revealing. There is emotion, and it is real. The pace is brisk enough to delude the unwary reader into a suspension of disbelief at first, but gradually the weakness of this chatty strategy becomes clear: Bush breezes through fundamental and earth-shattering decisions without slowing down to acknowledge their moral complexity. At the most important moments of his presidency - most notably, the decision to go to war in Iraq - he refuses to honestly consider opposing points of view or see the long-term, ancillary effects of what he is deciding.

Some of the decisions he makes are wise, like the belated move toward a counterinsurgency strategy in Iraq. In other cases, like Hurricane Katrina, he successfully defends his efforts and candidly acknowledges his mistakes. But as the pages turn, a familiar sense of the man unfurls: impatient, petulant, shallow - quite the opposite of the stem-cell decider. Bush writes that his true feelings as he found out about the 9/11 attacks - and chose to sit, famously impassive, as a Florida class read "The Pet Goat" - were, "My blood was boiling. We were going to find out who did this, and kick their ass." It was an understandable reaction, but an emotion he never quite transcended or transformed into strategic thought.

In the book, Bush never stops to wonder if, maybe, his team should have spent more time focusing on al-Qaeda before Sept. 11 - as the outgoing Clinton national-security team had strongly suggested - or whether he should have taken more seriously the infamous Aug. 6, 2001, memo from the CIA warning of an al-Qaeda attack on the homeland. And later, he never stops to wonder if the U.N. inspectors, whom Saddam Hussein had allowed back into Iraq, were not finding weapons of mass destruction because, maybe, uh, the WMD didn't exist. And still later, he expresses shock at the Abu Ghraib abuses without ever admitting - or, perhaps, finding out - that practices like enforced nudity, the use of dogs and stress positions had become common. And of course he never acknowledges the subsequent reporting, by multiple news outlets, that proved Abu Ghraib was different from other interrogation sites only in that photos were taken. In a particularly appalling moment, Bush simply decides to permit waterboarding enemy detainees because, as he told Matt Lauer, "the lawyer said it was legal." (His belief in the efficacy of torture is also at variance with other accounts, especially those provided by FBI agents, but he doesn't acknowledge that either.)

As I read on, trapped in the sketchy carelessness of this presidency, I was surprised by how angry I didn't become. For me, at least, weariness has replaced anger. Bush's was an exhausting presidency that will, I suspect, be remembered more for its waste - of time, lives, money, moral standing and economic strength - than for anything else. We have survived nearly a decade now since Sept. 11, and the cataclysmic events of that day have receded, not just in memory but in importance, compared with the global economic changes and Wall Street sociopathy that together challenge America's future pre-eminence. We have not been successfully attacked since, a matter of luck and skill. We do have Bush to thank, in part, for that - but far too much testosterone was spent kicking irrelevant butts and landing, breathless with self-regard, on carrier decks to celebrate victories that were Pyrrhic at best. We struggle to recover from the thoughtless carnage of his tenure.

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Google urges U.S. to challenge China Internet curbs

WASHINGTON (Reuters) – Google Inc. on Monday urged Western nations to challenge a growing list of Internet restrictions in China and around the world as a violation of global trade rules and to negotiate new trade deals to protect the free flow of online information.

"More than 40 governments now engage in broad-scale restriction of online information, a tenfold increase from just a decade ago," the search engine giant said in a policy brief that follows a censorship battle with China this year.

"These actions unnecessarily restrict trade, and left unchecked, they will almost certainly get worse."

With worldwide Internet commerce projected to soon reach $1 trillion, it is important to thousands of U.S. companies that China and other countries only be allowed to censor or restrict information in exceptional circumstances, Google said.

The California-based company, which in the first quarter of 2010 earned more than half of its revenues outside the United States, has had rocky relations with Chinese authorities since it announced in January it would no longer censor search results in mainland China.

It began rerouting visitors to its China website to a separate uncensored site in Hong Kong, but eventually changed the setup so mainland China users had to click on a link to go to the Hong Kong site.

China is the world's largest Internet market with 420 million users.

Google had about 25 percent of the market in the third quarter, a distant second to Baidu, a Chinese company that had about 73 percent, according to technology research firm IResearch.

In its paper, Google argued that government restrictions on the free flow of information threatened a broad array of U.S. companies, including other well-known Internet names like Facebook, Twitter, eBay and Amazon.

It accused China of tilting the marketplace in favor of Baidu, and said governments like Vietnam, Turkey, Russia, Pakistan and others have used one or more of four basic strategies to control information on the Internet:

-- Blocking access to a search engine or other Internet services or specific keywords, Web pages and domains;

-- Using licensing requirements or other means to force companies to remove certain search results;

-- Requiring certain websites to be removed or making whole domains invisible to users;

-- Encouraging self-censorship through means "including surveillance and monitoring, threats of legal action and informal methods of intimidation."

Washington should insist regulation of the Internet follow basic principles of the World Trade Organization's services pact, which require rules be clearly stated, administered in a way that does not discriminate against foreign companies and that decisions can be reviewed, Google said.

Governments that invoke a "public order" exception for an Internet restriction should be pressed, consistent with WTO rules, to explain why the measure is necessary to achieve the government's objective and to show why a less restrictive alternative would not achieve the same result, Google said.

The company also urged the United States, the European Union and other governments to take "concrete steps to ensure that rules in the next generation of trade agreements reflect new challenges of Internet trade."

This should be pursued as part of the Doha round of world trade talks and in bilateral and regional free trade pacts that the United States and the EU are negotiating, Google said.

(Reporting by Doug Palmer; Editing by Eric Walsh)

Inventories rise 0.9 percent in September

WASHINGTON – Businesses boosted inventories for a ninth straight month in September while sales rose by the largest amount since July.

Inventories increased 0.9 percent in September while business sales increased 0.5 percent, the Commerce Department reported Monday.

Continued strong gains in inventories and sales are seen as encouraging signs that the economic recovery will continue. Inventory rebuilding has provided critical support as the economy as struggled to emerge from a deep recession.

The 0.9 percent rise in inventories matched the August increase and pushed total inventories to a seasonally adjusted $1.4 trillion in September, the highest level since March 2009.

The increase was led by a 1.5 percent rise in inventories held by wholesalers. Inventories at the retail level rose 0.8 percent while manufacturing inventories increased 0.7 percent.

The 0.5 percent rise in sales in September reflected gains at all levels of the supply chain. In a separate report Monday, the government said that retail sales rose again in October, increasing by 1.2 percent, the best showing since last March.

Increased orders to fill empty store shelves have translated into higher production at the nation's factories.

Many businesses had undertaken a massive liquidation of inventories in early 2009 as they struggled to cope with a deep recession and plunging demand by keeping costs under control.

However, the swing from slashing inventories to rebuilding stockpiles has been a big factor in overall economic growth, starting in the October-December quarter of last year.

The overall economy grew at a modest annual rate of 2 percent in the July-September quarter with a big portion of that growth coming from inventory rebuilding.

The ratio of inventories to sales remained at 1.27 percent in September, the same as August. That means it would take 1.27 months to exhaust deplete existing stockpiles at the September sales pace.

Last test needed before declaring BP oil well dead

NEW ORLEANS – A pressure test on the blown-out BP well in the Gulf of Mexico was set to be finished early Sunday, the last step needed before the runaway well can finally be declared dead.

There was no word from company or government officials on whether the test had started as scheduled or when officials would say that the well had been permanently sealed, though the milestone was expected to be reached Sunday.

The test involves engineers exerting 15,000 pounds of weight against the cement plug to make sure it won't budge. They also will exert 1,150 pounds per square inch of pressure.

Sealing the well is an important step for the still-weary Gulf Coast residents, yet the disaster is far from over. Those who rely on the Gulf for their livelihoods are left to rebuild amid the businesses destroyed by once-oil-stained shorelines and fishing grounds. Even where the seafood is safe, fishermen struggle to sell it to consumers fearful that it's toxic.

News that the blown-out well would soon be dead brought little comfort to people like Sheryl Lindsay, who owns Orange Beach Weddings, which provides beach ceremonies on Alabama's coast.

She said she lost about $240,000 in business as nervous brides-to-be canceled their weddings all summer long and even into the remainder of the year. So far, she has only received about $29,000 in BP compensation.

"I'm scared that BP is going to pull out and leave us hanging with nothing," Lindsay said.

The Gulf well spewed 206 million gallons of oil until the gusher was first stopped in mid-July with a temporary cap. Mud and cement were later pushed down through the top of the well, allowing the cap to be removed.

The tragedy began April 20, when an explosion killed 11 workers, sank a drilling rig and led to the worst offshore oil spill in U.S. history.