captioning sponsored by wnet >> stewart: on this edition for saturday, january 30: it's the final weekend of campaigning in iowa before monday's caucuses; growing concern over the zika virus, as new cases are reported; and in our signature segment, west point cadets using social media to fight isis propaganda. next on pbs newshour weekend. >> pbs newshour weekend is made possible by: lewis b. and louise hirschfeld cullman. bernard and irene schwartz. judy and josh weston. the cheryl and philip milstein family. the citi foundation. supporting innovation and enabling urban progress. sue and edgar wachenheim, iii. corporate funding is provided

by mutual of america-- designing customized individual and group retirement products. that's why we are your retirement company. additional support has been provided by: and by the corporation for public broadcasting, and by contributions to your pbs station from viewers like you. thank you. from the tisch wnet studios at lincoln center in new york, alison stewart. >> stewart: good evening. thanks for joining us. after a year of campaigning, the first voting of the 2016 race for the white house finally begins in 48 hours. republican and democratic voters in iowa will meet in party caucuses monday night to choose their preferred standard bearers for their party's presidential nominations. most of the major candidates were in iowa today for the last weekend push. the candidates have collectively spent more campaign days in iowa than any other state, and now they can see the finish line.

>> i am asking you to caucus for me monday night. >> stewart: on monday night, iowans will gather in each of the state's 99 counties for caucuses. the greater competition is on the republican side, with a more crowded field. texas senator ted cruz has branded himself the "outsider" who can bring change. >> if you see a candidate who washington embraces, run and hide. >> stewart: the caucuses and the first-in-the-nation new hampshire primary eight days later may winnow the field of candidates. on the democratic side, vermont senator bernie sanders urged supporters to show up at the caucuses with any like-minded neighbors. >> beg, borrow, kidnap, do whatever you have to do. kidnapping illegal here in iowa? ( laughter ) >> stewart: former secretary of state hillary clinton campaigned today with her husband, the former president, and their daughter, chelsea. >> i am going to work to make college affordable for everybody. gll judy woodruff joins us from

the iowa caucus. judy, when you do the math, you realize there are only 30 delegation at state for the republicans, 44 for democrats. in the giant bug picture, that's about 1% of all the delegates so this isn't really about the math, is it? this is rail about something bigger. >> woodruff: it's not about the numbers. it's about that iowa is first. it's the reason the entire political press corps in the united states, which is usually somewhere between washington and new york, is now in the state of iowa. it's because the results in iowa catapult the winner and also the person who second, even third, on to the next contaft, new hampshire, and on that to south carolina and nevada. it's all about who came out of the first state where they went door to door appealing directly to voters, who did the best job of connecting gll the gll. >> stewart: the republicans are focusing on legacy, policy, health reform, immigration. ted cruz at the forefront of

this. i know you went to one of his rallies. how is that message landing? >> woodruff: i did go to one of the ted cruz rallies in ames. it was an overflow crowd in the convention meeting room there. very enthusiastic for ted cruz. his supporters are hard-core conservatives who absolutely love the message, the anti-obama message, down the line. but the question for cruz is whether the donald trump phenomenon, which has absolutely upended this race, is going to overcome the organization and the anti-obama message of ted cruz. and, frankly, the fact that there are just still so many candidates in the race, more than a dozen republicans are running. >> stewart: when we talk about how the democrats are positioning themselves, they are obviously both vying for obama supporters, hillary clinton presenting herself as heir in some ways. senator bernie sanders saying i think we should go farther on health reform. i think we should go after wall street. how is that playing out? >> woodruff: well, it is a

huge battle between clinton and sanders. clinton came into iowa, and people presumed she was going to walk away with this because of his ped gray, and resume. right now young people in the state are supporting sanders by enormous margins. she on the other hand has worked the state very hard. she learned some lessons from 2008 when she thought she was doing well and lost to barack obama. it is, allison, about who can carry on the obama legacy, but as you said, it's also, in bernie sanders' case, it's about who can do more with it than what president obama has done? who can do an even better job of bringing health care to all americans? bernie sanders talks about single-payer health care and so on down the list whether it's going after with the or some of these other issues that are important to liberals. >> stewart: and former secretary of state clinton won the endorsement of the "new york times," as well as the "des moines register" there in iowa.

what else does the "register" have planned today? >> woodruff: they are going to hold a news conference after this program is off the air announcing the last poll before the caucuses. historically the "des moines register" has done better than anybody else forecasting the outcome package they famously predicted barack obama was going to win the caucuses in 2008, when most others were predicting something different. so a lot of people are paying attention. it's so big that the "des moines register" is having a news conference to announce this poll when it comes out tonight. >> stewart: judy woodruff, thank you so much. >> woodruff: great to talk to you. >> stewart: at least 39 migrants and refugees died and 75 were rescued today trying to cross from turkey to the greek island of lesbos. the turkish coast guard rescued survivors and recovered bodies from a 56-foot boat that carried more than 100 people into the aegean sea. turkish officials say the boat capsized when it hit rocks shortly after launch. the officials said most of the

passengers were syrians, but there was also people from afghanistan and myanmar. the international organization for migration says more than 250 migrants have drowned this month on turkey-greece sea routes. in germany today, chancellor angela merkel, who has welcomed more than a million asylum seekers in the past year, said refugees should return home once the wars that led to their departures are resolved. merkel also said she's" disappointed" by some european countries turning away migrants. >> ( translated ): it is incomprehensible to me that a european union with 500 million inhabitants cannot take in, for example, one million syrians; whereas a country with five million inhabitants, like lebanon, is managing it. that does not give a good impression of our continent. we speak about our values every day, but we are not prepared to do our part. >> stewart: health officials are mobilizing to slow the spread of zika, the mosquito-borne virus possibly linked to almost 3,500 cases of birth defects in brazil, the country with the highest number of infections.

peru and jamaica reported their first cases today, joining the list of mostly latin american and caribbean countries experiencing the outbreak. at least 32 americans in 12 states and washington, d.c., and six canadians have been infected with zika, all of them from traveling abroad to countries with documented infections. the u.s. centers for disease control and prevention has opened an emergency operations center and advised pregnant women to avoid traveling to two dozen countries with zika cases. the world health organization, which holds an emergency meeting on zika monday in geneva, says as many as four million people in the americas could become infected with the virus for which there is no vaccine. learn more about the zika virus, including concerns over how it may affect a baby's brain. visit www.pbs.org/newshour. >> stewart: the united states

military said today the u.s.-led coalition carried out 33 more air strikes inside iraq and syria yesterday, targeting the islamic state in iraq and syria, known as isis. britain, for the first time, convicted a woman yesterday for traveling to syria to join isis, prosecutors saying she'd been self-radicalized by viewing extremist material on the internet. because social media is a key tool for isis obtaining new recruits, the u.s. is now increasing resources to fight the group online. that's the focus of tonight's signature segment. as the newshour's christopher booker reports, the u.s. is enlisting college students in the cause. >> reporter: at the midday formation at the u.s. military academy at west point, every cadet is subject to inspection. the way they stand, salute and march is part of their development of a u.s. army officer. but across this hudson river campus, in the basement of the social sciences building, a new aspect of cadet education is under way. while lacking the ritual and

repetition that dominate this prestigious 214-year-old academy, the virtual warfare tactics explored in this counterterrorism elective may one day prove to be as integral as the midday formation. >> information has always been crucial to warfare, and so when you take a look at propaganda, over the years it's always influenced the fight in some capacity. >> reporter: lieutenant colonel bryan price directs west point's combating terrorism center. >> if you take a look at the dollars that the united states government is putting into its counter-narrative campaign, and then you compare it to the emphasis that organizations like the islamic state is placing on it, i think we are operating at a deficit. >> reporter: the islamic state in iraq and syria, or isis, is running a 21st century social media blitz, and its preferred platform is twitter. cadets in this classroom are one

of 45 college teams developing an online campaign against extremists. the cadets are part of a "peer to peer" competition sponsored by the u.s. state department, the department of homeland security, facebook and edventure partners. >> this is the demographics and the generation that the islamic state and other jihadist organizations are targeting, so why not utilize what appeals to that generation? >> reporter: the target of price's class is what they cal"" fence sitters," people who may or may not be interested in joining isis or other jihadi groups. using a multi-platform approach, they hope to surreptitiously lure social media users already engaged in conversations surrounding jihad and other extremist ideas to their own web site, facebook page, twitter account and youtube channel we have obscured the social media pages to avoid compromising the cadets ongoing campaign. >> we are not thinking that we are going to create a social media campaign that is going to stop card-carrying members of the islamic state and have them put down their arms.

what we're trying to do is to identify at-risk youth and create a community online to which they can go get answers, information about the islamic state, about jihad. about islam. and those folks that haven't quite made up their mind yet. >> reporter: the cadets are searching for ways to insert their messages into the broader social media conversation, all without being detected as west point cadets. sometimes they do this by exploiting the use of twitter hashtags. >> the islamic state does a very good job of utilizing trending hashtags in order to get on sites and get on people... people's twitter feeds, where they wouldn't normally be on there. for example, so, if the super bowl was trending, they will include whatever messages they want, but they all include the hashtag, #superbowl. and so, we are trying, utilizing some of those same techniques. >> reporter: direct messaging also allows the cadets to interact one on one with users. >> this is someone from the

middle east in our 18-40 age bracket, telling us we have a nice page. >> reporter: during our visit, the cadets said they received a facebook message from someone they believed to be in the middle east. senior c.j. drew was one of the first to read it. >> in this... in this instance, we were reached out to by a person who had seen our page, and the first thing that came up to them was jihad. and they looked like they were a fence-sitter or someone we consider to be vulnerable to targeting by isis, and they wanted more information. and they wanted to engage us and tell us what jihad meant to them. >> reporter: drew, who speaks arabic, says their posts need to balance writing in english and other languages to look as authentic as possible. if a post has too much polish, the team risks exposing itself. >> we had a couple times where i was able to use hashtags that isis uses a lot, especially after the paris attacks, and we had multiple conversations with some of them. >> reporter: while west point's approach is to enter a conversation already under way, this new york university graduate class is looking for

individuals who might not be in the conversation at all. the class created the "7 train stop project," named after the new york city subway line that runs through the city's most diverse borough, queens. the online platform encourages immigrants to share their experiences living in the borough. n.y.u. professor colette mazzucelli teaches the class. >> we wanted to really focus on the difficulties, the vulnerabilities of immigrant integration and the ways in which immigrants are vulnerable. they might be more prone to indoctrination, so we felt that and therefore, we have to promote this idea of the american narrative, which is to integrate these immigrants in these communities well into their new environments. >> reporter: in the united states, the number of individuals radicalized by isis is believed to be lower than in europe, but is also believed to be increasing. so far, the u.s. government has brought criminal charges against about 80 people for isis-related activities, 61 cases last year--

the most new cases since the september 11, 2001 attacks. >> social media plays a big role in the recruitment of americans who join isis. >> reporter: seamus hughes, deputy director of the george washington university's program on extremism, is the co-author of "isis in america: from retweets to raqqa." ey are not finding it atd they mosques and community centers. >> reporter: hughes says radical messages online are like an echo chamber. >> we look at about 300 accounts of americans we believe to be isis supporters online over a six-month period, and what we saw is, they didn't hear dissenting voices, they only heard what they wanted to hear. they were only pushing the propaganda that they believed in. so, when you have people trying to interject themselves into the conversation, they were quickly pushed out. >> reporter: last year, hughes monitored an alleged isis supporter, an ohio man who called himself "lone wolf" on twitter. twitter regularly suspended his account, only to see "lone wol"" return again and again. the user was eventually arrested

after he allegedly released the home addresses of u.s. soldiers and urged people to kill them. >> it's very hard to try to figure out when someone's going to make that leap over to militancy. >> reporter: the peer-to-peer competition that n.y.u. and west point are involved in, also called p2p, is part of the state department's acknowledgement that it needs to change its approach. >> what we need to do is get in the middle, and get in the middle so that we can actually reach people who are at risk of recruitment. >> reporter: evan ryan is the assistant secretary of state for education and cultural affairs and a p2p competition judge. the u.s. state department, for lack of a better term, has struggled in this space. why do you think that is? >> well, listen, we can't do this on our own; we need to work with partners across the board. and that's what we are doing with this program p2p-- working with university students, but we are reaching out broadly to organizations, the private sector, other entities, putting minds together to think about how we can best address this problem. >> reporter: and one of the big questions, i guess, surrounding these private partnerships is

their dealings overseas. obviously facebook, twitter, these are global users, so they are juggling a lot of parameters. is it difficult to bring them into the fold? >> i think they understand this is where this demographic that we are trying to reach lives today. they live online. they live on these platforms. so, when we are able to sit down with a facebook and have them as a partner, that is really important to us. and we are looking forward to establishing more partnerships just like that. >> reporter: the p2p competition is not the first time the state department has experimented in this space. until last year, alberto fernandez was state's coordinator for strategic counterterrorism communications. to counter extremist propaganda, his team launched the "think again, turn away," campaign, which included the release of the video titled "welcome to the islamic state land," a graphic, minute-long video meant to undercut the group's message with satire. >> what we tried to do when i was there is, we tried to be extreme and radical, and we were too extreme and too radical for government but not extreme and radical enough for the challenge

we face. so, we kind of fell between two stools. >> reporter: now with the middle east media research institute, fernandez says while the p2p competition is a step in the right direction, it is only a small part of the new strategy needed. >> so, if you are talking about a revolutionary insurgent organization, which is the islamic state, it is going to take a while for government to turn that old battle ship around. i think the idea that, with all due respect, that west point cadets are going to be able to do that deep dive, to have that time to follow through and the depth to do it, is probably unlikely. >> reporter: perhaps, but the scale of the task does not seem to bother these cadets. in this competition of 45 teams, their entry was selected as one of three finalists. next month, they will head to washington to present their project. >> stewart: find out more about how the islamic state uses crowdsourcing as part of its

social media strategy. visit www.pbs.org/newshour. >> stewart: medical researchers have discovered a gene that increases the risk of schizophrenia, a mental illness that afflicts more than two million americans, sometimes causing delusions and hallucinations. the finding was first reported this week in the scientific journal "nature." steven mccarroll, an associate professor of genetics at harvard university, is the study's lead author. he joins me now from san francisco. professor, what was the conventional wisdom about schizophrenia prior to this study, and what was the missing piece of research with that brain disorder that scientists were looking so hard for? >> well, there have been hundreds of theories about schizophrenia over the decades, and it has been hard to tell which, if any of those theories

was right. what is new here say very strong genetic link to a very specific gene, and specific versions of that gene, and understanding of what that gene actually does and how it shapes the wiring of the brain. >> stewart: you can walk us through what that gene does? >> this gene, which is called c4-4, is in the neighborhood of the human genome, has hundreds of immune systems in it. that region was previously linked to schizophrenia. when we discovered though when we got to the bottom of it it and figured out what geefns propelg the signal is it is a gene, yes, that comes from the immune system but it has this night job in the brain and in fact it plays a role in instructing the wiring of the brain by causing ?apses, the-- synapses, the connections between nerve cells to be eliminated at particular times in development. >> stewart: now, this elimination, that's a normal occurrence. what you discovered is that it goes farther than that.

it goes haywire? >> that's right. all of us go through lots of synapse eliminations in our teens and 20s, and it involves the product of this gene. but what we believe based on these results is that that process somehow goes awry, and in particular, it may go into overdrive and result in the elimination of too many synapses. >> stewart: so what does this information-- how does it help us with the diagnosis of schizophrenia and with the treatment of schizophrenia? >> drugs for schizophrenia today treat just one of the symptoms of schizophrenia, which is the symptom called psychosis, which are the hallucinations and delusion delusions. those are actually just one of many symptoms of schizophrenia. and if you ask most patients what are the symptoms that most pother them, what they will tell you is it's the agonizing cognitive decline that many of them suffer in their first decade after diagnosis. there are no drugs today that address either the cognitive losses in schizophrenia or the

emotional withdrawal or the underlying disease. >> stewart: so if i'm understanding what you're say, the idea is this genetic component is a way to identify the disease before you even have to deal with the symptoms. >> well, the genetics is a way to understand the disease. you know, when we were in school, we learned it's genetics that we learned was this very simple genetics-- big "b," little "b." it turns out almost no common diseases work that way. they're shaped by the interplay of hundreds of genes. and discovering those genes is a way of telling us what those bee biological processes are so that you can point drug development toward the right biological processes. but testing for any one of those genes in the absence of that e key thing is going to beat't understanding the disease well enough to develop new medicines and make the same kinds of progress that we've seen in cancer over the last 10 or 20 years. >> stewart: steven

mccarroll, thank you so much for explaining your work. >> you're welcome. >> this is pbs newshour weekend, saturday. >> stewart: with no advance warning, a u.s. navy ship today passed within a dozen nautical miles of an island in the south china sea claimed by china, taiwan and vietnam. the pentagon said the u.s.s. "curtis wilbur," a guided missile destroyer, steamed near treeton island in the paracel islands to demonstrate what the pentagon called the right of free navigation in international waters. china, taiwan and vietnam insist on prior notification by ships in the area, a position the u.s. rejects. china called the wilbur's presence "intentionally provocative and extremely dangerous." facebook is banning private guns sales on its social network and its photo-sharing site, instagram. the company says its policy is meant to discourage peer-to-peer sales that are legal in the u.s. without f.b.i. background checks

on buyers. the change does not prevent licensed gun dealers from maintaining facebook pages as long as they do not use the site for sales. facebook said it would rely on users to flag posts and messages that violate its new rules. facebook's move follows president obama's call earlier this month to expand background checks on private gun sales and sales at gun shows. the number of reported concussions in the n.f.l. soared 58% this season, the highest in more than four years. the league says there were 182 concussions in regular season games this season, reversing a downward trend since 2012. the n.f.l. said it will study why concussions rose but emphasized there is better identification of head injuries during games. the release of the concussion data yesterday came a little more than a week before super bowl 50 kicks off in santa clara, california, next sunday. on the next pbs newshour weekend, a look at how oklahoma has become the nation's

earthquake capital. >> there was a magnitude 4.5 earthquake and it got folks worried that not only do these earthquakes pose a risk to life and property but also to the country's energy infrastructure. >> stewart: and finally, all three inmates who escaped from a maximum security orange county, california, jail eight days ago are back in custody tonight. county sheriffs officials say the two inmates who remained at large were arrested this morning when police in san francisco found them hiding in a stolen van. the third escapee, surrendered to authorities yesterday in santa ana. more than 10 people have been arrested in connection with the escape, including a female teacher from the prison who had what officials say was a significant role in planning the jailbreak. that's all for this edition of pbs newshour wild card. i'm alison stewart. thanks for watching. good night. captioning sponsored by wnet captioned by media access group at wgbh access.wgbh.org

>> pbs newshour weekend is made possible by: lewis b. and louise hirschfeld cullman. bernard and irene schwartz. judy and josh weston. the cheryl and philip milstein family. the citi foundation. supporting innovation and enabling urban progress. sue and edgar wachenheim, iii. corporate funding is provided by mutual of america-- designing customized individual and group retirement products. that's why we are your retirement company. additional support has been provided by: and by the corporation for public broadcasting, and by contributions to your pbs station from viewers like you. thank you.

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