0:00:01.173,0:00:03.032 So, I love making tools 0:00:03.032,0:00:05.035 and sharing them with people. 0:00:05.357,0:00:06.746 I remember as a child, 0:00:06.746,0:00:10.038 my first tool I built[br]was actually a microscope 0:00:10.038,0:00:14.079 that I built by stealing lenses[br]from my brother's eyeglasses. 0:00:14.385,0:00:15.954 He wasn't that thrilled. 0:00:16.195,0:00:18.552 But maybe because of that momement, 0:00:18.552,0:00:19.690 30 years later, 0:00:19.690,0:00:21.714 I'm still making microscopes. 0:00:22.415,0:00:25.986 And the reason I built these tools[br]is for moments like this. 0:00:27.560,0:00:30.003 (Video) I have black things in my hair -- 0:00:30.003,0:00:32.278 MP: This is a school in [the Bay Area.] 0:00:32.864,0:00:37.542 The living world far supersedes[br]our imagination 0:00:37.542,0:00:39.532 of how things actually work. 0:00:39.532,0:00:41.983 (Video) Oh my God! 0:00:43.773,0:00:44.992 MP: Right ... 0:00:44.992,0:00:46.599 "Oh my God!" 0:00:46.788,0:00:50.320 I hadn't realized this would be[br]such a universal phrase. 0:00:51.195,0:00:53.148 Over the last two years, 0:00:53.148,0:00:54.226 in my lab, 0:00:54.226,0:00:56.513 we built 50,000 Foldscopes, 0:00:56.513,0:00:59.235 and shipped them to 130[br]countries in the world 0:00:59.235,0:01:02.082 at no cost to the kids we sent them to. 0:01:02.397,0:01:03.759 This year alone, 0:01:03.759,0:01:05.748 with the support of our community, 0:01:05.748,0:01:09.852 we are planning to ship one million[br]microscopes to kids around the world. 0:01:10.114,0:01:11.558 What does that do? 0:01:11.707,0:01:15.601 It creates an inspiring community[br]of people around the world, 0:01:15.601,0:01:17.296 learning and teaching each other, 0:01:17.296,0:01:20.989 from Kenya to Kampala[br]to Kathmandu to Kansas. 0:01:21.329,0:01:23.909 And one of the phenomenal things[br]that I love about this 0:01:23.909,0:01:25.833 is the sense of community. 0:01:26.050,0:01:27.375 There is a kid in Nicaragua 0:01:27.375,0:01:31.725 teaching others how to identify[br]mosquito species that carry dengue 0:01:31.725,0:01:34.166 by looking at the larvae[br]under a microscope. 0:01:34.166,0:01:36.737 There is a pharmacologist[br]who came up with a new way 0:01:36.737,0:01:38.980 to detect fake drugs anywhere. 0:01:39.451,0:01:41.643 There is a girl who wondered, 0:01:41.643,0:01:43.495 how does glitter actually work? 0:01:43.495,0:01:47.486 And discovered the physics[br]of crystal information in glitter. 0:01:47.825,0:01:49.342 There is an Argentinian doctor 0:01:49.342,0:01:53.417 who's trying to do field cervical cancer[br]screening with this tool. 0:01:53.787,0:01:57.548 And yours very truly found[br]a species of flea 0:01:57.548,0:02:02.618 that was dug inside my heel in my foot[br]one-centimenter deep. 0:02:03.448,0:02:08.325 Now, you might think[br]of these as anomalies, 0:02:08.325,0:02:10.422 but there is a method to this madness. 0:02:10.705,0:02:12.765 I call this frugal science. 0:02:13.006,0:02:18.725 The idea of sharing experience of science[br]and not just the information. 0:02:19.123,0:02:20.471 Remind you, 0:02:20.471,0:02:22.578 there are a billion people on this planet 0:02:22.578,0:02:25.116 who live with absolutely[br]no infrastructure: 0:02:25.116,0:02:26.753 no roads, 0:02:26.753,0:02:28.158 no electricity, 0:02:28.158,0:02:30.993 and thus, no health care. 0:02:31.262,0:02:35.498 Also there a billion kids[br]on this planet that live in poverty. 0:02:35.825,0:02:37.494 How are we supposed to inspire them 0:02:37.494,0:02:39.955 for the next generation[br]of solution makers? 0:02:40.304,0:02:43.075 There are health care workers[br]that we put on the line 0:02:43.075,0:02:45.016 to fight for infectious diseases, 0:02:45.016,0:02:49.473 to protect us with absolutely[br]bare-minimum tools and resources. 0:02:50.656,0:02:52.398 So as a lab at Stanford, 0:02:52.398,0:02:56.358 I think of this from a context[br]of frugal sciecnce 0:02:56.358,0:02:58.642 and building solutions[br]for these communities. 0:02:58.963,0:03:03.545 Often we think about being able to do[br]diagnosis under a tree, off-grid. 0:03:03.880,0:03:06.753 I'll tell you two examples[br]today of new tools. 0:03:06.753,0:03:08.764 One of them starts in Uganda. 0:03:08.989,0:03:10.425 In 2013, 0:03:10.425,0:03:14.494 on a fieldtrip to detect[br]schistosomiasis with Foldscopes, 0:03:14.494,0:03:16.847 I made a minor observation. 0:03:17.147,0:03:18.747 In a clinic, 0:03:18.747,0:03:20.200 in a far, remote area, 0:03:20.200,0:03:24.041 I saw a centrifuge[br]being used as a doorstop. 0:03:24.264,0:03:26.555 I mean quite literally the doorstop. 0:03:26.757,0:03:28.445 And I asked them and they said, 0:03:28.445,0:03:30.495 "Oh, we don't actually have electricity, 0:03:30.495,0:03:34.131 so this piece of junk[br]is good as a doorstop." 0:03:34.913,0:03:35.910 Centrifuges, 0:03:35.910,0:03:37.465 for some of you who don't know, 0:03:37.465,0:03:40.712 are the pinnacle tool to be able[br]to do sample processing. 0:03:40.712,0:03:43.477 You separate components[br]of blood or body fluids 0:03:43.477,0:03:46.197 to be able to detect[br]and identify pathogens. 0:03:46.563,0:03:49.420 But centrifuges are bulky, expensive -- 0:03:49.420,0:03:51.751 costs around 1,000 dollars -- 0:03:51.751,0:03:53.760 and really hard to carry out in the field, 0:03:53.760,0:03:56.066 and of course, they don't[br]work without power. 0:03:56.066,0:03:57.399 Sound familiar? 0:03:57.691,0:04:00.354 So we started thinking[br]about solving this problem, 0:04:00.354,0:04:01.927 and I came back -- 0:04:01.927,0:04:03.634 kept thinking about toys. 0:04:03.914,0:04:06.260 Now ... 0:04:06.260,0:04:08.264 I have a few with me here. 0:04:08.264,0:04:10.324 I first started with yo-yos ... 0:04:10.324,0:04:12.763 and I'm a terrible yo-yo thrower. 0:04:12.979,0:04:14.753 Because these objects spin, 0:04:14.753,0:04:15.750 we wondered, 0:04:15.750,0:04:18.087 could we actually use[br]the physics of these objects 0:04:18.087,0:04:20.294 to be able to build centrifuges? 0:04:21.329,0:04:23.819 This was possibly the worst[br]throw I could make. 0:04:24.587,0:04:26.095 But you might start realizing, 0:04:26.095,0:04:29.024 if you start exploring[br]the [safe space] of toys -- 0:04:29.024,0:04:31.652 we tried these spinning tops, 0:04:31.652,0:04:33.662 and then in the lab, 0:04:33.662,0:04:35.689 we stumbled upon this wonder. 0:04:35.971,0:04:37.326 It's the Whirligig, 0:04:37.326,0:04:38.394 or a Buzzer, 0:04:38.394,0:04:39.469 or a [Roudrun.] 0:04:39.469,0:04:42.017 A couple of strings and a little disk, 0:04:42.017,0:04:44.349 and if I push, it spins. 0:04:44.557,0:04:46.853 How many of you have played[br]with this as a kid? 0:04:46.853,0:04:48.724 This is called a button-on-a-string. 0:04:48.724,0:04:50.461 OK, maybe 50 percent of you. 0:04:50.461,0:04:52.042 What you didn't realize -- 0:04:52.042,0:04:54.238 that this little object 0:04:54.238,0:04:58.751 is the oldest toy[br]in the history of mankind. 0:04:59.007,0:05:00.676 5,000 years ago --- 0:05:00.676,0:05:04.375 we have found relics of this object[br]hidden around on our planet. 0:05:05.223,0:05:08.985 Now the irony is we actually[br]don't understand 0:05:08.985,0:05:10.945 how this little thing works. 0:05:10.945,0:05:12.651 That's when I get excited. 0:05:12.964,0:05:15.122 So we got back to work, 0:05:15.122,0:05:16.912 wrote down a couple of equations. 0:05:17.223,0:05:20.559 If you take the input torque[br]that you put in, 0:05:20.559,0:05:22.813 you take the drag on this disc, 0:05:22.813,0:05:24.741 and the twist drag on these strings, 0:05:24.741,0:05:27.153 you should be able[br]to mathematically solve this. 0:05:27.153,0:05:29.661 This is not the only equation in my talk. 0:05:29.971,0:05:31.826 10 pages of math later, 0:05:31.826,0:05:34.704 we could actually write down[br]the complete analytical solution 0:05:34.704,0:05:36.218 for this dynamic system. 0:05:36.563,0:05:40.000 And out comes what we call Paperfuge. 0:05:40.197,0:05:41.498 That's my postdoc, 0:05:41.498,0:05:42.591 Saad Bhamla, 0:05:42.591,0:05:44.260 who's the co-inventor of Paperfuge. 0:05:44.260,0:05:45.256 And to the left, 0:05:45.256,0:05:48.107 you see all the centrifuges[br]that we are trying to replace. 0:05:48.107,0:05:53.042 This little object that you see right here 0:05:53.042,0:05:56.175 is a disc, a couple[br]of strings and a handle. 0:05:56.470,0:05:58.100 And then I spin. 0:05:58.100,0:05:59.102 And I push, 0:05:59.102,0:06:00.195 it starts to spin. 0:06:00.195,0:06:03.292 Now, when you realize, 0:06:03.292,0:06:05.715 when you do the math, 0:06:05.715,0:06:08.228 when we calculate the rpm for this object, 0:06:08.228,0:06:12.816 mathematically we should be able[br]to go all the way to a million rpm. 0:06:13.011,0:06:15.107 Now there is a little twist[br]in human anatomy, 0:06:15.107,0:06:18.106 because the resident frequency[br]of this object is about 10 hertz, 0:06:18.106,0:06:19.493 and if you ever played piano, 0:06:19.493,0:06:21.697 you can't go higher[br]than two or three hertz. 0:06:22.106,0:06:25.613 The maximum speed we've been[br]able to achieve with this object 0:06:25.613,0:06:27.565 is not 10,000 rpm, 0:06:27.565,0:06:29.269 not 50,000 rpm -- 0:06:29.269,0:06:30.839 120,000 rpm. 0:06:31.107,0:06:33.697 That's equal to 30,000 g-forces. 0:06:33.934,0:06:37.164 If I was to stick you right here[br]and have it spin, 0:06:37.164,0:06:40.141 you would think about the types[br]of forces you would experience. 0:06:40.441,0:06:45.395 One of the factors of a tool like this[br]is to be able to do diagnosis with this. 0:06:45.777,0:06:49.243 So I'm going to do a quick demo here. 0:06:50.514,0:06:54.061 So this is a moment where I'm going[br]to make a little fingerprint. 0:06:54.061,0:06:56.122 A tiny drop of blood is going to come out, 0:06:56.122,0:06:57.299 if you don't like blood, 0:06:57.299,0:06:58.712 you don't have to look at it. 0:06:59.092,0:07:00.539 Here is a little lancet. 0:07:00.539,0:07:02.432 These lancets are available everywhere, 0:07:02.432,0:07:03.819 completely passive. 0:07:03.819,0:07:09.116 And if I've had breakfast today ... 0:07:10.191,0:07:11.677 That didn't hurt at all. 0:07:12.153,0:07:15.836 OK, I take a little capillary[br]with a drop of blood -- 0:07:15.836,0:07:18.064 now this drop of blood has answers, 0:07:18.064,0:07:19.687 that's why I'm interested in it. 0:07:19.910,0:07:23.119 It might actually tell me whether[br]I have malaria right now or not. 0:07:23.489,0:07:25.547 I take a little capillary, 0:07:25.547,0:07:27.765 and you see it starts leaking in. 0:07:28.072,0:07:30.772 I'm going to draw a little more blood. 0:07:32.782,0:07:35.025 And that's good enough for right now. 0:07:35.519,0:07:39.924 Now, I just seal this capillary[br]by putting it in clay. 0:07:43.588,0:07:45.659 And now that's sealed the sample. 0:07:45.987,0:07:48.139 We're going to take the sample, 0:07:48.139,0:07:50.357 mount it on Paperfuge. 0:07:57.275,0:08:00.564 A little piece of tape[br]to make a sealed cavity. 0:08:01.071,0:08:04.090 So now the sample is completely enclosed. 0:08:07.163,0:08:10.104 And we are ready for a spin. 0:08:11.257,0:08:13.321 I'm pushing and pulling with this object. 0:08:13.321,0:08:16.484 I'm going to load this up ... 0:08:16.484,0:08:18.790 and you see the object starts spinning. 0:08:18.790,0:08:20.827 Unlike a regular centrifuge, 0:08:20.827,0:08:24.629 this is a counter-rotating centrifuge. 0:08:24.629,0:08:27.711 It goes back and forth, back and forth, 0:08:27.711,0:08:29.659 and I'm charging it up -- 0:08:29.659,0:08:31.864 and you see it builds momentum. 0:08:32.309,0:08:33.359 And now -- 0:08:33.359,0:08:35.134 I don't know if you can hear this -- 0:08:35.134,0:08:37.053 30 seconds of this 0:08:37.053,0:08:41.524 and I should be able to separate[br]all the blood cells with the plasma. 0:08:42.098,0:08:45.019 And the ratio of those[br]blood cells to plasma -- 0:08:45.019,0:08:47.033 (Applause) 0:08:48.678,0:08:52.437 Already, if you see right here, 0:08:52.437,0:08:54.216 if you focus on this, 0:08:54.216,0:08:57.502 you should be able to see[br]a separated volume 0:08:57.502,0:08:59.383 of blood and plasma. 0:08:59.383,0:09:02.778 And the ratio of that actually tells me[br]whether I might be anemic. 0:09:03.157,0:09:07.115 One the of aspects of this is we build[br]many types of Paperfuges. 0:09:07.350,0:09:11.839 This one allows us to identify[br]malaria parasites 0:09:11.839,0:09:13.679 by running them for a little longer, 0:09:13.679,0:09:17.268 and we can identify malaria parasites[br]that are in the blood 0:09:17.268,0:09:20.614 that we can separate out and detect[br]with something like a centrifuge. 0:09:20.957,0:09:25.460 Another version of this allows me[br]to separate nucleic acids 0:09:25.460,0:09:28.944 to be able to do nucleic acid tests[br]out in the field itself. 0:09:29.605,0:09:34.088 Here is another version that allows me[br]to separate bulk samples, 0:09:34.088,0:09:35.681 and then finally, 0:09:35.681,0:09:37.699 something new that we've been working on 0:09:37.704,0:09:42.263 to be able to implement the entire[br]multiplex test on an object like this. 0:09:42.522,0:09:46.859 So where you do the sample preparation[br]and the chemistry in the same object. 0:09:47.635,0:09:49.040 Now ... 0:09:49.040,0:09:50.193 this is all good, 0:09:50.193,0:09:52.070 but when you start thinking about this, 0:09:52.070,0:09:54.341 you have to share these tools with people, 0:09:54.341,0:09:57.724 and one of the things that we did[br]is we just got back from Madagascar -- 0:09:57.724,0:10:00.224 this is what clinical trials[br]for malaria look like -- 0:10:00.224,0:10:01.223 (Laughter) 0:10:01.223,0:10:03.532 You can do this while having coffee. 0:10:03.701,0:10:05.717 But most importantly, 0:10:05.717,0:10:09.670 this is a village six hours from any road. 0:10:10.346,0:10:14.932 We are in a room with one of the senior[br]members of the community 0:10:14.932,0:10:16.468 and a health care worker. 0:10:16.468,0:10:20.035 And it really is this portion of the work[br]that really excites me the most -- 0:10:20.035,0:10:21.035 that smile. 0:10:21.035,0:10:24.909 To be able to share simple but powerful[br]tools with people around the world. 0:10:25.598,0:10:28.096 Now, I forgot to tell you this -- 0:10:28.096,0:10:30.667 that all of that cost me 20 cents to make. 0:10:31.510,0:10:34.416 OK, in the negative time I have left, 0:10:34.416,0:10:36.649 I'll tell you about the most recent -- 0:10:36.649,0:10:37.650 (Laughter) 0:10:37.650,0:10:39.469 invention from our lab. 0:10:39.671,0:10:41.346 It's called Abuzz. 0:10:41.730,0:10:45.776 The idea that all of you[br]could help us fight mosquitoes. 0:10:45.776,0:10:48.260 You could all help us track our enemies. 0:10:48.260,0:10:52.182 These are enemies because they cause[br]malaria, Zika, chikagunya, dengue, 0:10:52.182,0:10:56.722 but the challenge is that we actually[br]don't know where our enemies are. 0:10:56.989,0:11:00.021 The world map for where[br]mosquitoes are is misssing. 0:11:00.391,0:11:02.070 So we started thinking about this. 0:11:02.070,0:11:04.243 There are 3500 species of mosquitoes, 0:11:04.243,0:11:05.669 and they're all very similar. 0:11:05.669,0:11:07.108 Some of them are so identical 0:11:07.108,0:11:10.752 that even an entomologist cannot[br]identify them under a microscope. 0:11:11.239,0:11:13.047 But they have an Achilles' heel. 0:11:13.047,0:11:15.916 This is what a mosquito flirting[br]with each other looks like. 0:11:16.296,0:11:18.266 That's a male chasing a female. 0:11:18.548,0:11:23.380 They're actually talking to each other[br]with their wingbeat frequencies ... 0:11:23.380,0:11:25.922 and thus, they have a signature. 0:11:26.732,0:11:30.347 We realized that using a regular phone, 0:11:30.347,0:11:32.911 a five to 10 dollar flip phone -- 0:11:32.911,0:11:35.036 how many remember what this object is? 0:11:35.036,0:11:36.038 (Laughter) 0:11:36.038,0:11:40.222 We can record these acoustic[br]signatures from mosquitoes. 0:11:40.222,0:11:42.090 I'll tell you exactly how to do this -- 0:11:42.090,0:11:43.818 I caught some mosquitoes outside. 0:11:43.818,0:11:46.665 Unlike Bill, I'm not[br]going to release them. 0:11:46.957,0:11:49.963 But I will tell you how[br]to record from this. 0:11:49.963,0:11:52.507 All you do is you tap them and they fly. 0:11:52.507,0:11:53.755 You can first test -- 0:11:53.755,0:11:55.530 I can actually hear that. 0:11:55.530,0:11:57.900 And you bring your phone[br]which has microphones -- 0:11:57.900,0:12:00.366 it turns out the mics[br]are so damn good already, 0:12:00.366,0:12:01.788 even on regular phones, 0:12:01.788,0:12:04.113 that you can pick up[br]this [near-field] signature. 0:12:04.113,0:12:06.274 And since I'm out of time, 0:12:06.274,0:12:09.965 let me just play the recording[br]that I made a day ago. 0:12:10.557,0:12:12.754 (Mosquitoes buzz) 0:12:12.754,0:12:15.499 This is all the charming sound[br]that you heard before 0:12:15.499,0:12:16.863 that you all love. 0:12:18.937,0:12:20.381 One of the contexts of this 0:12:20.381,0:12:23.791 is being able to do this[br]with a regular cell phone 0:12:23.791,0:12:26.951 allows us to map mosquito species. 0:12:27.658,0:12:29.373 Using a flip phone, 0:12:29.373,0:12:32.638 we mapped one of the largest[br]acoustic databases 0:12:32.638,0:12:37.502 with 25 to 20 species of mosquitoes[br]that carry human pathogens. 0:12:37.782,0:12:39.615 And from this and machine learning, 0:12:39.615,0:12:41.276 anybody who uploads this data, 0:12:41.276,0:12:43.330 we can identify and tell the probability 0:12:43.330,0:12:46.134 of what species of mosquitoes[br]you're actually working with. 0:12:46.134,0:12:47.203 We call this Abuzz, 0:12:47.203,0:12:48.845 and if any of you want to sign up, 0:12:48.845,0:12:50.169 just go to the website. 0:12:50.675,0:12:54.817 Let me close with something that's very[br]important and dear to my heart. 0:12:55.600,0:12:59.570 One of the challenges of today[br]is we have terrible problems. 0:12:59.570,0:13:02.552 We have a billion people[br]with absolutely no health care, 0:13:02.552,0:13:03.550 climate change, 0:13:03.550,0:13:04.760 biodiversity loss, 0:13:04.760,0:13:06.329 on and on and on. 0:13:06.329,0:13:09.279 And we hope that science[br]is going to provide the answer. 0:13:09.646,0:13:11.935 But before you leave this theatre today, 0:13:11.935,0:13:14.066 I want you to promise one thing. 0:13:14.066,0:13:16.658 We're going to make science accessible. 0:13:17.250,0:13:19.412 Not just to the people who can afford it, 0:13:19.412,0:13:21.446 but a billion others who can't. 0:13:21.904,0:13:26.365 Let's make science and scientific[br]literacy a human right. 0:13:27.620,0:13:32.491 The moment that you pass the tingling[br]feeling of making a discovery 0:13:32.491,0:13:34.670 to another child, 0:13:34.670,0:13:38.360 you're enabling them to be[br]the next group of people 0:13:38.360,0:13:40.610 who will actually solve these problems. 0:13:40.610,0:13:41.698 Thank you. 0:13:41.698,0:13:43.060 (Applause)