Rafael Nadal's ailing left knee may continue to bother him until the end of the month, his coach said Monday.

Nadal practiced for 90 minutes with Nicolas Massu of Chile on Monday, his fourth straight day of training since arriving in the country for his first match in more than seven months.

Chelsea goalkeeper Petr Cech has been voted the Czech Republic's player of the year for 2012.

The 30-year-old Czech international won Monday's poll of players, coaches, football federation officials and journalists for the fifth consecutive year and record sixth time overall.

A member of a hugely popular Japanese girl band has shaved her head and issued a tearful videotaped apology for violating the megagroup's no-dating rule.

The spectacle has sparked debate in Japan over whether the band AKB48 exerts too much control over its performers.

Police in Germany say someone dressed as the Cookie Monster has sent a second note regarding a stolen cookie sculpture — this time saying he wants to return it.

But officials aren't sure the person in the photo actually stole the 20-kilogram (44 pound), century-old sculpture.

The world's most advanced tuberculosis vaccine failed to protect babies against the infectious disease, according to a new study in South Africa.

The vaccine, MVA85A, was designed to improve protection from the only existing tuberculosis vaccine, BCG, which is routinely given to newborns. Though the new vaccine appeared safe, scientists found no proof it prevented tuberculosis, an airborne disease that kills more than 1 million people worldwide every year.

The oil and gas industry is trying to ease environmental concerns by developing nontoxic fluids for the drilling process known as fracking, but it's not clear whether the new product will be widely embraced by drilling companies.

Houston-based energy giant Halliburton Inc. has developed a product called CleanStim, which uses only food-industry ingredients. Other companies have developed nontoxic fluids as well.

Abu Dhabi's Etihad Airways says net profit tripled last year as the fast-growing carrier added routes and code-share arrangements in its expanding rivalries with other premium Gulf airlines.

Government-owned Etihad said on Monday that 2012 net profit jumped to $42 million, compared to $14 million in 2011. Revenue rose 17 percent to $4.8 billion.

A U.S.-funded study released Monday said both Israeli and Palestinian schoolbooks largely present one-sided narratives of the conflict between the two peoples and tend to ignore the existence of the other side, but rarely resort to demonization.

The research by Israeli, Palestinian and American researchers, billed as setting a new standard for textbook analysis, tackled a particularly fraught issue — longstanding Israeli claims that the Palestinians teach incitement and hatred of Israel in their schools.

Lionel Messi extended his record streak by scoring in his 12th consecutive Spanish league game to give leader Barcelona a 1-1 draw at Valencia on Sunday, while Atletico Madrid remained perfect at home through 20 games in all competitions.

Midfielder Ever Banega struck first for Valencia in the 33rd, only for Messi to level for the visitors from the penalty spot six minutes later.

Mario Balotelli marked his return to Serie A by scoring both goals — including the winner in added time — in AC Milan's 2-1 win over Udinese on Sunday.

Balotelli gave Milan the lead in the 25th minute at the San Siro by redirecting a cross from Stephen El Shaarawy at the edge of the box with one touch. Then after Giampiero Pinzi had brought Udinese level in the 55th, Balotelli put Milan back in front with a penalty four minutes into injury time.