Here are some of the latest health and medical news developments, compiled by the editors of HealthDay:

More U.S. Students Getting Free and Subsidized School Meals

The number of American students receiving free or low-cost lunches rose 17 percent between 2006-07 and 2010, from 18 million to 21 million, according to a New York Times analysis of federal government data.

Florida, Nevada, New Jersey, Tennessee and seven other states had increases of 25 percent or more during that time.

"These are very large increases and a direct reflection of the hardships American families are facing," Benjamin Senauer, a University of Minnesota economist who studies the meals program, told The Times.

He added that the increase has happened so quickly "that people like myself who do research are struggling to keep up with it."

Free school meals are available to students in families with incomes up to 130 percent of the poverty level, which works out to $29,055 for a family of four. Subsidized lunches priced at 40 cents are available to students in four-member households with incomes up to $41,348, The Times reported.

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Former Players Sue NCAA Over Head Injuries

A class-action suit by four former U.S. college athletes claims the National Collegiate Athletic Association (NCAA) has been negligent regarding awareness and treatment of brain injuries to athletes.

The suit, which represents three former football players and a former soccer player, was filed in the United States District Court for the Northern District of Illinois, The New York Times reported.

One of the plaintiffs is 22-year-old Derek Owens. He suffered a brain injury last year while playing football for the University of Central Arkansas. He has suffered from headaches and depression, is under medical care, and can never play a contact sport again.

In the past five years, there's been a growing awareness of brain injuries in contact sports. The legal action by the college players followed lawsuits filed this year by dozens of former pro football players who claim the National Football League was negligent in its handling of brain trauma.

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Obesity Screening, Counseling Added to Medicare Coverage

Screening and counseling for obesity have been added to Medicare coverage, the Centers for Medicare & Medicaid Services (CMS) announced Tuesday.

Beneficiaries who screen positive for obesity will receive face-to-face counseling each week for one month and then every other week for an additional five months.

A beneficiary may receive one face-to-face counseling session a month for an additional six months if he or she has achieved a weight reduction of at least 6.6 pounds during the first six months of counseling.

More than 30 percent of Medicare beneficiaries are estimated to be obese, which is directly or indirectly linked to many chronic diseases, including diabetes and cardiovascular disease.

"Obesity is a challenge faced by Americans of all ages, and prevention is crucial for the management and elimination of obesity in our country," CMS Administrator Dr. Donald M. Berwick said in a CMS news release. "It's important for Medicare patients to enjoy access to appropriate screening and preventive services."

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White House Appeals Ruling on Cigarette Warning Images

A judge's order blocking a U.S. government requirement that cigarette packs carry graphic warning images is being appealed by the Obama administration.

In a ruling earlier this month, U.S. District Judge Richard Leon said tobacco companies are likely to succeed in a lawsuit to stop a Food and Drug Administration requirement to place the images across the top half of all cigarette packs, the Associated Press reported.

Leon said the images, which include photos of diseased and dead smokers, go beyond conveying the facts about the health risks of smoking and amount to stop-smoking advocacy.

The FDA requirement was to take effect next year, but Leon blocked it until after the tobacco companies' lawsuit is resolved, which could take years, the AP reported.

The Obama administration's notice of appeal was filed Tuesday with the U.S. Court of Appeals in Washington.

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Fewer Uninsured Children in U.S.: Report

The number of U.S. children without health insurance fell from 6.9 million in 2008 to 5.9 million in 2010, a new report says.

The Georgetown University analysis of new health insurance data from the Census Bureau also revealed that 34 states had a significant decrease in the rate of uninsured children, the Associated Press reported.

The federal health care law has played a key role, according to experts. The law requires states to maintain income eligibility levels and discourages other barriers to coverage.

Florida had the most progress, with the number of uninsured children in that state declining from 667,758 to 506,934 over the three-year period. However, Florida still has one of the highest rates of uninsured children in the nation, the AP reported.

The highest rate of uninsured children was in Nevada and the lowest rate was in Massachusetts. Increased rates of uninsured children were seen in Kansas, Minnesota and Wisconsin.

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Michael Jackson's Doctor Sentenced to 4 Years in Jail

Dr. Conrad Murray, physician to the late pop star Michael Jackson, was sentenced to 4 years in prison by a Los Angeles judge who called his actions a "disgrace to the medical profession," MSNBC.com reported.

After Jackson died in 2009 at age 50, investigators linked Jackson's frequent use of the drug propofol -- supplied to the singer by Murray -- as a possible contributor to his death.

According to MSNBC.com, Murray told police detectives that Jackson had been receiving nightly doses of propofol as a sleep aid, even though the drug is typically used only in hospitals and has not been sanctioned as a sleep treatment. Murray, who was contracted to be paid $150,000 a month for his services to Jackson, said he gave the pop star propofol on the day he died.

During sentencing, Judge Michael Pastor said Murray violated his obligation to his patient and "has absolutely no sense of remorse, absolutely no sense of fault, and is and remains dangerous" to the community.

Murray declined to testify at his trial, but in a documentary said that he does not consider himself guilty.

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Laptops' Wi-Fi May Damage Sperm: Study

A new study raises questions about whether using wi-fi on a laptop could harm a man's sperm.

Semen samples from 29 healthy donors were each divided into two pots. One pot was stored for four hours next to a laptop wirelessly connected to the Internet and the other pot was stored under identical conditions, but without the laptop, BBC News reported.

The researchers found that sperm in the pot next to the laptop were damaged. Their ability to swim was reduced and they had changes in the genetic code they carry. While heat can harm sperm, the researchers don't believe this damage was caused by heat from the laptop.

The study appears in the journal Fertility and Sterility.

Experts said this test was not conducted in a real-world setting and the findings should not cause men undue worry. However, they recommended more studies, BBC News reported.

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