>> this is "bbc world news america." >> funding of this presentation is made possible by the freeman foundation, newman's own foundation, giving all profits to charity and pursuing the common good for over 30 years, and union bank. >> at union bank, our relationship managers work hard to know your business, offering specialized solutions and

capital to help you meet your growth objectives. we offer expertise and tailored solutions for small businesses and major corporations. what can we do for you? >> and now, "bbc world news america." "bbc world news america" reporting from washington. , twitterrading began makes a soaring debut on the new are stock exchange, but will investors keep it aloft? the toronto mayor strikes again. justdays after his ministr -- days after he committed smoking crack cocaine, video services of

him threatening to kill someone. countsthere as russia down to the sochi games. >> roaring off on its way. the olympic torch on board. you can feel it in your stomach. >> welcome to our viewers on public television in america and also around the globe. twitter, which has helped to fuel revolutions and bring us the latest from lady gaga, saw it stocks soar. can they keep the momentum going? twitter takes flight on the new york stock exchange.

top tweeters including patrick stewart taking part in the social media phenomenon. one of twitter's founders on the floor of the exchange. the share price soars. simple tool. yet, people have done so many amazing things with it. team has spent the last few weeks of playing to investors why a company which is yet to make a profit will be a great bed. 26 with thisin tweet from one of the founders. than 230 million users ranging from the president celebrating election victory to celebrities like justin bieber telling his followers that of brazil has been incredible. twitter even treated the details

of its own share sale but now it has to prove that it is serious business. decided that despite its lack of profits, twitter was worth around $81 billion. a much bigger and profitable social network, facebook, is worth nearly $117 billion. is valued at $160 billion. the u.s. continues to generate .uge web businesses at an event in london, entrepreneurs from both sides of the atlantic discuss what can be learned from silicon valley. >> a track record, it is possible. come to the valley, you will make a lot of money. you have a place for people do that in europe. >> the secret is that we encourage and foster creativity, innovation, a culture of trial and error. >> investors are already

showing great faith of that twitter can start making big profits. find plentyll soon of advertisements among their tweets. >> for more on the market reaction to twitter's ipo, let's speak to our business correspondent who was in new york. why are investors so keen on twitter when it has not even turned a profit yet? >> it is been in existence for seven years and has yet to make any money. what investors are really investing in is its potential for growth. they see a lot of opportunity when it comes to twitter and a lot of that comes from its potential in revenue with mobile advertising. it isms of advertising, on mobile devices where that really is growing a lot. twitter, about more than 70% of its users are on mobile phones. as we heard in the piece, we're going to be be seeing a few more adverts coming on to our mobile

devices when we are using twitter. moneymaker,al big potential revenues for twitter. >> is it the profile of the that makes it potentially profitable? best comparison when you are talking about twitter is facebook. facebook also has that same sort of younger kind of demographic. it also has older users, which you also see. with twitter, you also see a lot of companies or famous investors. so, in terms of the kinds of people that are using it, it is sort of skewedounger and older. i think the difference is in terms of its popularity for its ipo. when you look at facebook, when it became a publicly traded company him it had already been in existence for for quite a long time whereas twitter is still a very young company.

in terms of the potential for growth, there are still a lot of there for twitter. >> thank you. speaking speaking of facebook, one woman who knows a lot about growing a big social media company is -- zuckerberg. the company was founded by her husband, mark. now, she heads her own media company and she has written a new book about the role technology should play in our lives. i spoke to her earlier from new york. twitter debuts on the stock exchange this morning, and fraught forhich is facebook. what do you think that facebook learned from that experience? every company that you see is learning from the companies that came before it. facebook learned a lot from the ipos that came before us. i been on my media book tour

blitz all day so i have not quite had a chance to dive into the opening day but it looks like it has been very very successful or twitter. personally, i remember when i first recognized twitter as a site to be reckoned with on the social media scene. i write a lot about that in my book. >> did you ever dreamed of both facebook and twitter would be trading on wall street? >> no, i never dreamed that, but it is really exciting to see two companies, both of which i feel like i was there from the beginning of because i have so many friends who were there in the early days of twitter and are still there and it seems like such a new exciting world. >> your book is about how we untangled our wired lives. what is your number one tip for all of us? >> i think my number one tip is to be your authentic self. it used to be that we felt we needed to be someone very different in our refashion life,

someone at home, someone with our friends. the interesting reality is that you really only get one identity online. someone with a savvy google searching ability. we are facebook friends with our colleagues. of it takes is a little bit searching to uncover everything about us. so, it really is very important to be your authentic self and remember that you only get one identity online now. , wef we are authentic cannot possibly get into trouble. what if we massively over share? >> there's definitely definitely a thing as over sharing. the context i talk about is you speak to a lot of parents who are very concerned about their teenagers on social media, their young kids. they will tell you they are concerned and they will go and

be over shares themselves. one of the other takeaways is especially his parents in this digital age, we need to really take stock of our own behavior while we are looking at how we raise the state still -- this digital generation. realize this?ou >> it was definitely having my own son. that was my wake-up moment. i had been at facebook for six years nonstop. everyone is thinking about what can we do right now? what are we innovating in right now? what are we building now? it was really having my son that made me think about the future, that made me think, do i want him to grow up in this world where we are expected to be , glued to smart phones, answering e-mails seconds after they come in? is that really the answer? had a, then i

responsibility to spark that discussion. >> being mark zuckerberg's sister, you had to be three times as good as any man just to get to where they were. is that still true today? >> i am trying to move beyond whicho make my own name, is why i am so excited about my books that are coming out. this is really my ability to tell my own story. i talk a lot in the book about the glass half full and half empty reality for me at having such a famous last name in silicon valley. am so thankful for the opportunities and being part of the zuckerberg family. both that facebook and beyond facebook. on the other hand, it is really interesting to go about your life living in the shadow of such a successful sibling and struggling to make your own mark on the world. hopefully, with these books i can start to do that.

>> thank you so much for joining us. >> thank you. to the social media media firestorm has erupted over the actions of the toronto mayor. on tuesday, he admitted using crack cocaine. today, he has more explaining to do. this time it is over a new video. he isin a rambling rage, using the words kill and murder. we are in toronto and we have the latest. the toronto camera, mayor is swearing and using threatening languages. >> you cannot tell who this is

directed at. it was filmed. it is net another and harassment for the already embattled mayor. shortly after this video became public, he spoke to the media and said he was sorry. >> do you need help? goyour colleagues want to away. why won't you go away? >> i want to tell you that i saw a it is extremely embarrassing. the whole world will see it. i don't have her problem with that, but it is extreme embarrassing. >> despite these latest revelations, he continues to work here at his office. coming after his admission that he had smoked crack cocaine and been drunk in public. many of his colleagues are saying, enough is enough, time to quit. he was elected as mayor in 2010 and has a strong and loyal supporter base.

many say is the reason why he is refusing to leave. a large proportion will say that he is damaging toronto's reputation. this is the video here. what were you thinking when you watched it? >> it was another example of how pathetic this man is. it is almost enough to elicit some sympathy. that is very unprofessional if you're trying to be a role model. this is not a reality show. it goes on. the media continues to demand answers from the mayor and many others demand his resignation. for now, he is still on the job. >> the toronto mayor. in other news now from around the world, mass evacuations have been ordered in the philippines and the closure of schools as the most--- most powerful

typhoon of the year is approaching. is threatening to cut through the central islands. the former palestinian leader asser arafat had traces of radioactive substance in his body. they say they cannot say it caused his death. they also found evidence on polonium on the close and the long is that he had with him when he died years ago. our world affairs editor has more details. they're always did seem to be something highly suspicious about yost or arafat's death. four weeks after eating a suspect meal, he died in the palace hospital. a year ago, with the doubt stronger than ever, his body was exhumed. by the group that

was hired was as cautious as it could possibly be. the team did not ask lewd polonium poisoning. yet, is any possibility that poloniumcould in just 210 and that could be an innocent act? >> it was present in the room where he was at that time. i strong traces were found in the remains of mr. arafat's is takenin things he with him he went into the hospital. .races were unexpectedly high in one case, 18 times above normal. the swiss teens said that his symptoms were mostly consistent with polonium poisoning.

they agreed that the forensic evidence supported the idea that he had been poisoned. they could not be finally certain. conclusion isheir fair. they say that it is moderately supportive of evidence that polonium was used to kill yost or arafat. they cannot really say anything more. >> many palestinian support the demand for a new inquiry, yet arafat's widow will not apportion blame. >> everybody wants to accuse israel, i cannot accuse them. to document this crime. i wanted to document it for history. >> there was no autopsy on his body at the time. been samples have destroyed. so, who did kill yasser arafat? , most palestinians don't

have any doubt at all. they blame israel. it is true that he was loathed by most israelis. out that byf points the time he started to get really ill, yasser arafat was completely finished as a political force. this report has done is to add to the accusations. still no final smoking gun. john simpson, bbc news. >> the mystery deepens. you are watching "bbc world news america," still to come. inside of fukushima's reactor number four. we get rare access. this is a difficult and very dangerous process for removing nuclear fuel that is about to get underway. less than a week after its leader was killed, pakistani taliban have chosen a new head. mullah fazlullah is a hard-line commander whose men planned the

attack on the teenager malala yousafzai. >> this is a man apparently now in control of the pakistan taliban and. mullah fazlullah is regarded as being even more brutal than his predecessor. one of his more recent targets was this army general. he was visiting troops along the pakistan-afghan border in september. he and two other soldiers were killed by a roadside bomb. he accuses the pakistan army, intelligence agencies, and politicians of taking orders from what he calls infidels. in other words, the west. they took control of the swat valley in northeast pakistan. they imposed an extremely harsh regime.

to berance from flogging heading carried out in public. -- punishments from flogging to be heading carried out in public. they were eventually pushed out by the army. since then, the attacks continued. amonger malala yousafzai the victims. she was shot in the head for her support of education for girls. she survived that the treatment in britain. today's announcement that mullah willllah is the new leader anger by theth people here. >> in japan, engineers of the crippled fukushima nuclear plant

are about to start a difficult and dangerous operation. their task, to remove thousands of uranium fuel rods from one of the damaged reactors. one of the small group of journalists that were allowed inside of reactor building for for the first time since the earthquake and tsunami struck. >> this is fukushima reactor four. inside is nearly 500 tons of toxic nuclear fuel. fuel twodiation to bombs. this tsunami shattered three of the reactor buildings. by the time i came here, this is what reactor for look like. now, it has been transferred. today, for the first time since journalists were allowed inside.

beenis really why we have brought in here. i am standing on top of what used to be reactor building four. you can see this is a cooling pool where there is a large amount of nuclear fuel. 1300 down inside of that. is going toration began. >> it will be a difficult and delicate operation. the fuel might have been damaged, but putting it out like this could be dangerous. some anti-nuclear groups say an accident during this operation could be catastrophic. what of the n in charge? >> that sort of scenario is impossible. large-scale disaster is impossible. >> i personally think that it is close to impossible, he says.

even if this operation goes without a hitch, it is just the tip of a very large, very radioactive iceberg. >> we were back inside of reactor building number four. this behind me here is reactor three. to radiation really shot up more than two and a half thousand. >> how on earth are they going to start finishing the other reactors. nobody knows. >> inside of a damaged nuclear reactor there. a space mission with special tar .o -- special cargo this is part of a special ceremony that the russians have planned ahead of the sochi games next year. the report contains some flash photography.

theust before boarding russian rocket, the three asher not held aloft a replica of the olympic torch. the real one was already snowed on board. they blasted off into space. >> and, we have liftoff. quirks and their it goes, roaring off on its way to the international space station. feel so loud and you can it in your stomach. >> a beautiful launch. 45 seconds, liftoff. >> this was the six hour flight. then, the hatch was opened and the torch was on board. on saturday, it will be the

first olympic torch to go out in space itself when it leaves the station on a spacewalk. it has not been the only olympic adventure during the russian torch relay. one torch crashed its way to the north pole on an icebreaker. >> when i met the president of the organizing committee, i asked him why all of the attention? special country. there are very few countries in the world, few nations that are capable to send an icebreaker to the north pole. >> the torch relay has been used to promote president q2 himself. putin himself. he personally lit the flame. in sochi itself, although the building work is continuing, the main venues are ready.

apart from the huge 40,000 feet stadium that will only be used for the lavish opening ceremony. >> the olympic torch going where no torch has gone before. that brings today's podcast to a close. thank you for watching. see you back here tomorrow. -- that brings today's broadcast to a close. thank you for watching. >> get international news at bbc.com/news. >> funding of this presentation is made possible by the freeman foundation, newman's own foundation, giving all profits to charity and pursuing the common good for over 30 years, union bank,

>> at union bank, our relationship managers work hard to understand the industry you operate in, working to nurture new ventures and help provide capital for key strategic decisions. we offer expertise and tailored solutions in a wide range of industries. what can we do for you? >> "bbc world news" was presented by kcet, los angeles.