Meryl Streep and Sandra Bullock share actress award

Voters for the Critics' Choice Awards could not pick an outright best actress winner, so split the prize between Meryl Streep and Sandra Bullock.

Streep, a winner for Julie and Julia, and Bullock, who won for The Blind Side, both attended the Los Angeles ceremony to collect their awards.

Iraq war drama The Hurt Locker picked up the best film award, with Kathryn Bigelow also winning for best director.

Avatar won five prizes, including best action movie and technical awards.

Directed by James Cameron, the ex-husband of Bigelow, the film was honoured for its cinematography, editing, art direction, sound and visual effects.

Kathryn Bigelow previously directed Point Break and K19: The Widowmaker

The best actor award went to Jeff Bridges for country music film Crazy Heart.

The best supporting actor and actress awards were collected by Christoph Waltz for Inglourious Basterds and Mo'Nique for Precious respectively.

Quentin Tarantino's World War II epic Inglourious also won best original screenplay and ensemble cast, which included Brad Pitt, Eli Roth and Michael Fassbender.

Musical movie Nine, starring Penelope Cruz, Kate Hudson and Nicole Kidman, failed to win in any of the 10 categories in which it was nominated.

Bullock, who on Friday donated $1m (£614,798) to aid the medical charity Doctors Without Borders' relief effort in Haiti, used her time on the winners' podium to talk about the disaster.

"We're all so lucky to be here tonight when so many others are in pain," she said.

"I hope we can all send good love and thoughts and whatever we can."

Last year, voters for the Critics' Choice Awards plumped for Slumdog Millionaire as best film, paving the way for the British hit to sweep the Oscars, where it won eight awards on the night.

Kodak sues Apple and RIM over iPhone and Blackberry

Camera maker Kodak has said it will sue Apple and Research In Motion (RIM), the makers of the iPhone and Blackberry, over technology used in their handsets.

Kodak has filed a complaint with the US International Trade Commission (ITC).

It alleges the iPhone and Blackberry use technology for previewing pictures that infringe Kodak patents.

It has also filed two separate suits against Apple that claim infringements of patents relating to digital cameras and certain computer processes.

Kodak has asked the ITC to bar both firms from shipping the phones and has asked for undisclosed monetary damages.

RIM and Apple declined to comment.

Legal scrutiny

"We've had discussions for years with both companies in an attempt to resolve this issue amicably, and we have not been able to reach a satisfactory agreement," said Laura Quatela, chief intellectual property officer at Kodak.

"In light of that, we are taking this action to ensure that we protect the interests of our shareholders and the existing licensees of our technology."

The patent for Kodak's picture previewing technology has already been the subject of one dispute.

On 17 December 2009, an ITC judge ruled that camera-enabled phones made by Samsung infringed upon the Kodak patent.

The separate filing against Apple has also been scrutinised in court in a case against Sun Microsystems.

In that case, a federal jury determined that Sun's Java programming technology had infringed Kodak's patents. Sun later agreed to pay Kodak in return for a license for the patents at issue.

Apple is currently in the middle of a legal dispute with phone giant Nokia.

In October, Nokia alleged that the iPhone infringed 10 of its "fundamental" patents relating to wireless technologies.

Apple countered with its own lawsuit in December, accusing Nokia of copying its technology.

Since then Nokia has complained to the ITC and launched a further legal action that alleges "virtually all" of Apple's products infringe on its patents.

New strategies may cut screening errors, says US study

US scientists have found a way they believe may cut the number of mistakes made by medical staff looking for breast and cervical cancers.

Writing in the journal Current Biology, the researchers say that people in all walks of life looking for rare events often miss them.

But accuracy improves if people first get used to looking at samples of what they need to find.

Screening professionals said it was a recognised problem.

They carried out a study which showed that the number of mistakes made during a visual search varied according to the chances of finding the "target".

Time searching

Twelve volunteers were asked to identify target items in X-ray images of assorted objects in empty bags.

The accuracy of their search was monitored as the frequency of the target was altered.

The laboratory results are to be tested in clinics and airports.

The study found that the amount of time the observers spent looking for something depended on how often if appeared.

"If you don't find it often, you often don't find it," said lead author, Jeremy Wolfe of Harvard Medical School.

"If you are trying to find 20 cases of breast cancer from 40 mammograms, you'll find more of them than if you look for the same 20 cases from 2,000 mammograms.

"From an evolutionary point of view it makes sense for people to give up searching more quickly if they don't expect to find what they were looking for," he said.

"If you know berries are there, you keep looking until you find them. If they are never there, you don't spend your time hunting."

But this causes difficulties when the aim is to accurately spot rare phenomenon like cancers or bombs in travellers' luggage.

Instant feedback

The authors say that one benefit of staff doing a booster exercise before starting work is that it helps them to visualise what they are looking for and improves their search success rate in the subsequent session.

They say that this kind of exercise could also sharpen search skills by providing instant feedback.

In the real world it often takes many months for radiographers and radiologists to discover if they have made mistakes.

The research has been welcomed by the Society of Radiographers.

Chief executive Richard Evans said: "The difficulty of spotting abnormal results among large numbers of normal cases is a recognised problem.

"I look forward to seeing more details about this research, but radiographers would welcome techniques which help ensure the best possible standards."

He pointed out that the NHS already monitors the performance of everyone involved in breast screening through a regular audit.