it's been shown to help combat determine atightize. it -- determina tightize. it comes down to the fact that stress is bat. mirth and humour is good for us. that is why humor, as long as it's point of view is helpful for us. >> the new book is ha. the science of when we laugh and why. good of you to join us. >> thank you for thissing me. >> the show may be over, but the conversation continues on the website aljazeera.com. or facebook or google+. you can join us on twitter. see you next time. >> you're watching al jazeera, i'm jonathan betz in new york with the top stories. >> secretary of state john kerry is praising the afghan people, calling them courageous and committed. more than 7 million turned out for the presidential elections, twice as many as in 2009. a possible new clue in the disappearance of malaysia airlines flight 370, australia confirmed electronic signals are cannot with the frequency of the black box. the ping was heard near the ascertain area in the indian ocean. >> an argument with soldiers likely provoked forces in fort hood. >> specialists

it's been shown to help combat determine atightize. it -- determina tightize. it comes down to the fact that stress is bat. mirth and humour is good for us. that is why humor, as long as it's point of view is helpful for us. >> the new book is ha. the science of when we laugh and why. good of you to join us. >> thank you for thissing me. >> the show may be over, but the conversation continues on the website aljazeera.com. or facebook or google+. >> welcome to al jazeera america. i'm del walters. these are the stories we're following for you. >> it's probably the best information that we've had. >> investigators now saying new signals are detected possibly from those black boxes of a missing plane. >>> 100 days behind bars. egypt continues to hold all three al jazeera journalists. tensions rising in ukraine as government protesters take over a building in the eastern part

it's been shown to help combat determine atightize. it -- determina tightize. it comes down to the fact that stress is bat. mirth and humour is good for us. that is why humor, as long as it's point of view is helpful for us. >> the new book is ha. the science of when we laugh and why. good of you to join us. >> thank you for thissing me. >> the show may be over, but the conversation continues on the website aljazeera.com. or facebook or google+. >> on al jazeera america when science intersects with hope. >> i'm hoping to give someone a prosthetic arm for under $1000 >> inovation finds oppurtunity >> a large earthquake would be an inconvenience rather than a disaster... >> and hardware meets humanity >> this is some of the best driving i've ever done >> eventhough i can't see... >> techknow our experts take you beyond the lab >> we're here in the vortex... >> and explore the technology changing our world. only on al jazeera america >> you're watching al jazeera america. i'm jonathan betz in new york with the top stories. >> hopeful clues in the missing malaysian