SciTech Now Episode 501

In this episode of SciTech Now, we take a look at how Larva can be a solution to the planet’s waste; The hi-tech courtroom of the future; how photosynthesis is being used to harvest clean energy; and discovering the historic Battle of the Alamo through virtual reality.



Coming up... larva farms.

You just got to get on eye level with the larva and see what they're trying to do.

You can admire how much they really want to eat.

The high-tech courtroom of the future.

Basically, trials are paperless.

How photosynthesis is being used to harvest clean energy.

There will be a continuous flow of water and a continuous correction of the hydrogen yields.

Experiencing the historic Battle of the Alamo through virtual reality.

A portal will appear in front of you that's just a doorway, and that doorway is into 1836.

It's all ahead.

Funding for this program is made possible by...


I'm Hari Sreenivasan.

Welcome to 'SciTech Now,' our weekly program bringing you the latest breakthroughs in science, technology, and innovation.

Let's get started.

With the ability to eat twice their body mass a day, larva may be the solution to our planet's waste.

Professor David Hu is conducting research to see how the appetites of these tiny creatures can combat human waste issues.

Here's a look.

What is the 'dog food bowl' problem?

Eating requires you to make direct contact with the food, and food of a given size has only so many slots around it.

And as soon as all those slots are filled, they can only really eat at this maximum rate.

So the size of the bowl determines how many puppies can be eating at any given time.

We basically want to determine, if you have 100, 1,000, 10,000, how do those numbers affect how quickly food is consumed?

But if you want to study this problem at that scale, you're gonna need something a little different from a puppy.

[ Upbeat, distorted music plays ]

I mean they're really just hungry little babies.

♪♪ My name is David Hu, and I study how animals move.

We use engineering and physics techniques to build models for how these animals can do these amazing tasks.

Such as eating enormous amounts of food.

The black-soldier-fly larva can eat twice their body mass in a day.

They'll eat vegetable matter, road kill.

If you're dead, they will eat you.

But if they've got other options, they'll go for other stuff, too, like pizza.

And this makes them incredibly useful.

They're raised in these fly-larva farms, where the dream of these larva farms is to bring in 100 tons of restaurant and human home-consumer waste to these vast bins and have 100 tons of food waste be eaten in an entire day, and then they can multiply, and their own bodies can be used for agriculture.

To be used as a high-protein food for chickens or farm-raised fish.

So, in growing these larva, one of the big questions is how quickly can they eat, because the whole idea is to allow them to eat as much food as possible.

And so if you have more and more larva, is food just consumed just as quickly?

Is there an actual limit to their appetite?

So, we placed these orange slices inside these bins of different larva, and we observed how quickly they could eat.

The results were consuming.

Naively, you'd expect the rate of food consumption to be proportional to the number of larva that are around it, but they happen to eat almost 10 times faster.

So this idea that each larva is just eating at a constant rate only gives a small part of the picture.

And so Dr. Hu and grad student Olga Shishkov began looking at the behavior of individual larva.

First thing we noticed is that the larva only ate for small fractions of an hour.

Most of the time, three fourths of an hour, a larva that's around a piece of food is just blocking the other larva.

They would ordinarily take up a spot and slow down the rate of food consumption.

So it wasn't their individual appetites that enabled them to consume massive quantities of food.

Undeterred, the researchers decided to approach their problem as only mechanical engineers could.

If you want to measure the pressure in a room, you don't trap every single molecule in a room.

What you do is come up with rules for how groups of these molecules would behave under certain conditions.

With this perspective, you can start to see the maggots' motion in a new light.

Even though they're alive, we can really treat them as sort of non-living things that follow these really simple rules.

Without any food, they simply just follow each other and slosh back and forth, but as soon as you put small food scraps into the larvae, they start generating these tiny vortices, whirlpools.

The food causes a chain reaction.

Individual larvae can be activated by the motion of their neighbors.

And if a single larva takes a bite of food, it is super activated, and it continues to swarm around and look for food.

And they actively move throughout these blockades, these larvae that are sitting around and not eating.

And that helps other larvae get to the food, kind of like a buffet line.

People are sort of pushing them out of the way just so each of them grabs one bite.

You can imagine the buffet line would be eaten much faster.

Now that the researchers have discovered the larvae's solution to the dog food bowl problem, their next step is to see if they can create a mathematical model for all this maggoty emotion.

You can see the larvae as kind of like a -- like waves in an ocean.

They're sloshing back and forth, and here they're generating their own sloshing forces.

So, how could we actually measure the forces of them sloshing?

And so what we did was we put them in a device, kind of like a vise, where we sort of measure the forces they push up against the walls.

And we find that as soon as you put in food, they really activate and they really push against the walls.

And then the pushing sort of decreases and decreases as the food goes away.

Believe it or not, Dr. Hu's aim is not to create more and more fodder for your nightmares.

Yeah, after we die, this is what's gonna happen to us -- these larvae.

But they can -- [ Laughs ] They can provide a lot of use before we're gone.

It's the one thing that doesn't have any human diseases and that will get rid of all our food waste.

That is -- 1/3 of the food that goes into our restaurants and our homes is actually thrown in the trash.

Much of which ends up as water-polluting sludge oozing out of a landfill.

You just got to get on eye level with the larvae and see what they're trying to do.

You can admire how much they really want to eat.

I think they're pretty cute.

Okay, fine, they do give me nightmares.

For 'Science Friday,' I'm Luke Groskin.

♪♪ ♪♪

The courtroom of the future has arrived, with the latest digital technology advancing trial techniques, including making it possible to observe evidence faster and more easily.

Judge Gail Prudenti, dean of the Hofstra University Maurice A. Deane School of Law, joins us to discuss the future of courtrooms.

So, let's talk a little bit about how law and technology have changed and also specifically the courtroom.

I mean, I still have the same images in my mind of what a courtroom looks today as watching a black-and-white episode of 'Perry Mason.'

I'm sure, and I'm sure a lot of people do.

But, you know, trial advocacy is all about persuasion.

And what technology has done -- it really has revolutionized the practice of law, especially in the area of law-firm management and what lawyers are looking for when they hire new lawyers, as well as how they perform in the courtroom.

So, at Hofstra, we believe getting our students practice-ready, not only practice-ready for tomorrow, but for the day after tomorrow.

And what we have found is our new center for law and technology is something that will prepare our students to better serve the community, to better serve the lawyers, and to better serve the underprivileged, you know, and people who don't have access to justice as easily as others.

What does that modern-day courtroom look like now?

Oh, the modern-day courtroom really is a courtroom where the trials are paperless.

The attorneys use iPads, and we train our attorneys and our attorney students to use iPads.

Everyone has a touchscreen, whether it's the judge, whether it's the jurors, or whether it's the trial attorneys.

And we use a program that's called TrialDirector that will allow the witnesses, will allow the jurors, will allow the judge, and will allow the attorneys to best advocate their positions and get that up-close-and-personal view of evidence and, actually, of witnesses and their testimony and how they're testifying.

So, it is something that has revolutionized the way trial practice is going on, not only in the federal system, but in the state-court system, as well.

So, if you're sitting the jury box, somebody doesn't have to walk around and show you a Ziploc bag or point to an area.

It's actually just showing up on a screen in front of you at the magnification that might make most sense.

It is, and it's also identified by the witness right on the screen.

You know, they identify it.

They can identify a portion of the evidence that's crucial as the attorney directs them to that part.

And it also allows the witness to refresh their recollection.

Even so much better than just asking that question, you know, they're seeing the scene, let's say, the scene of the crime once again...


...or they're seeing an accident once again.

And they're taking that look, and they're saying, 'I remember when I was there.

I remember when I first saw that, and this is what I saw.'

The lawyers of the future will be able to e-file -- so, they no longer go to court just to file their papers.

And many courts do it now, both in the federal system and the state system.

They will be able to e-discover, meaning getting ready for trial and not going through hundreds of boxes, but basically doing it with the use of technology.

And number three, which is very important because the practice of law is a business, they will be able to do e-billing.

Are there examples of cases, when they were being tried in these sorts of settings, where possibly it could have impacted the outcome?

Very much so.

Let me give you one example that I saw up close and personal.

And that was in the Commercial Division of the state of New York.

There was one attorney who was so well versed in technology, and basically he did everything paperless.

And there was another attorney.

And I have to tell you, my heart went out to him because he was going through boxes.

He -- I could see that the jurors were getting lost, that they were getting bored.

And for the amount of time it was taking not only to mark the exhibits, but to show everyone the exhibits, he was definitely at a disadvantage.


So, I think, to equal that playing field, you are going to see the practice of law and trials revolutionized so that everyone has all of these abilities, as well as all of the technology.

So, the presentation of the case was compromised by somebody's lack of ability to be digital.

Exactly right.

And I'll tell you another example of what I've seen.

In our courtroom of the future, we have many, many clinics at Hofstra Law, and one helped victims of Superstorm Sandy collect benefits and collect insurance.

And then there was a denial of insurance benefits.

And then there was litigation over that.

And our students learned and practiced, under the leadership of fabulous Professor Krieger.

And they were able to try their cases and bring their claims with the use of technology and helped hundreds of people when maybe they could have only helped a dozen before.

All right.

Judge Gail Prudenti of Hofstra University, thanks so much for joining us.

Oh, it was my pleasure.

Thank you for having me.

For years, scientists have used artificial photosynthesis to generate clean energy.

This process typically requires electricity or natural gas, but now researchers have developed a new device that's more than twice as efficient and runs only on water and sunlight.

Joining us via Google Hangout to discuss this breakthrough is Zetian Mi, professor of electrical engineering and computer science at the University of Michigan in Ann Arbor.

First of all, plants have been doing this for millions of years or hundreds of thousands of years, right?

How close have we come to being as efficient as Mother Nature?

Okay, that's right.

And nature has been doing this for millions of years, and the current efficiency is about .6%. So, it's actually a very low-efficiency process.

So, as electrical engineers, our job is to make this a much more efficient process.

So, the questions I challenge myself and my students are, 'Can we make this 10 times, 100 times more efficient?'

Actually, if you look at solar cells, currently the solar-cell energy efficiency can reach about 40%-plus.

That's already much more efficient than the natural photosynthesis process.

But the challenge for solar cells is you convert solar energy into electricity.

Electricity is not storable.

So, the cost associated with the battery is actually very high.

That limits the usage of solar cells.

In the artificial photosynthesis process, we convert solar energy into storable, chemical fields -- hydrogen, in this case.

So we can eliminate the cost and also the efficiency loss associated with batteries.

So, instead of having to store the energy from the wind and from the sun in some sort of a giant battery that can eventually be converted to electricity that we want for our car or whatever, you're just saying, convert the sunlight into hydrogen.

Exactly. Into hydrogen.

How kind of energy-intensive is the process?

Because we've had this ability before, but we've had to use fossil fuels, ironically, natural gas or coal-powered electricity, to make this process work.

That's right.

And today, in U.S. alone, we produce nearly 10 million metric tons of hydrogen.

And this is mostly produced from fossil fuels through a process known as steam reforming.

This indeed is a very energy-intensive process.

So, in the artificial photosynthesis process, as we do, so, we use only solar energy.

There's no carbon dioxide emission in this process.


What are the ingredients to get to the hydrogen?

Okay, that's a great question.

Actually, this is a very simple device.

I'm sure you are familiar with solar-cell panels.


So, our device is very similar to a solar-cell panel, except it's actually easier to make.

So, we put nanostructured semiconductors -- in this case, gallium nitride, which is also the material used in LED lighting.

We put them on the silicon wafer, and we tailor the size to be in the nanoscale about .001 of the width of human hair.

And we change the properties so that they become a very efficient photocatalyst.

And then we put this wafer, which could be only a few inch or larger, immerse that in water, and shine sunlight.

Then hydrogen and oxygen bubbles are produced.

You're putting this nanoscale substance on a wafer, sticking it in water, adding sunlight.

That's it.

That's it.

And, you know, gallium nitride has been known for decades.

Gallium nitride is one of the most produced semiconductors, next only to silicon.

But for decades, people cannot transform this material to be a very efficient photocatalyst.

So, what we have discovered is, by growing this using a standard process known as molecular beam epitaxy, we can tailor the material properties to bring the water molecules into hydrogen and oxygen very efficiently.

And we can achieve that by using the nanoscale materials.

If gallium nitride is so widely known and available, I'm assuming it is inexpensive to make this?

Well, so, gallium nitride is so well produced, the cost has been reduced dramatically over the years.

So, for example, use LED lighting as an example.

And we are using the same material, a very similar manufacturing process.

So, that's the most exciting part of our discovery -- the device we build is based on a very scalable manufacturing process.

It uses very well known, very well produced semiconductors.

So, that will make our technology scalable and potentially very low cost.

I'm assuming there's some sort of a container that's capturing the hydrogen and capturing the oxygen and there's no more water that's gonna be left, right?

In the real applications, we can envision that there will be a continuous flow of water and a continuous collection of the hydrogen fields generated, which will be used, you know, for fuel cell vehicles, as an example.


So, basically, this would be the stuff that your hydrogen car can run on.

But as you said, there's also already so much hydrogen being manufactured in a very energy-intensive manner in the United States every year.

So you could actually switch the process to this and have a cleaner way of making hydrogen.

Exactly. Much cleaner way.

And I think the very exciting part of this is we can produce hydrogen directly on site.

We know that the current hydrogen-generation process is a very energy-intensive process, but it's also very challenging for hydrogen distribution and transportation.

Now let's imagine that we can generate hydrogen directly on site whenever, wherever we need that.

That will not only reduce the cost of hydrogen itself, but, more importantly, reduce the cost associated with hydrogen distribution and transportation.

So, give me an example of -- How much hydrogen and oxygen can you generate from, say, an ounce or a gallon of water?

Okay, so, you know, our preliminary calculations have shown that, for example, if we use a 1-by-1-meter-square photocatalyst wafer that we produce and using about 100-by concentrated sunlight, then we can produce a few kilogram of hydrogen per day.

And that's enough to power our fuel cell vehicles for many, many miles.

So [chuckles] you could have one of these 1-by-1-meter wafers in your backyard, add a gallon of water or two to it every couple of days, and have enough fuel to run your car.

I think that's what will happen in the very near future.

All right, Zetian Mi from the University of Michigan, thanks so much for joining us.

Thank you so much for the interview.

[ Computer keys clacking ] ♪♪

One of the top tourist destinations in San Antonio, Texas, is the site of the historic Battle of the Alamo.

Now, with the help of virtual reality, visitors can experience the legendary siege of the Alamo like never before.

Here's a look.

So, our app is sort of a new way to actually experience the Alamo.

We started over a year ago in a mind-set of trying to provide an additional way that the citizens and the visitors of the Alamo can actually really gain knowledge of the experience.

Well, the conversation society is very excited about the new technology that allows us to interpret and re-interpret historic sites without altering the physical fabric.

You can really take people to a past event, like the battle for the Alamo, through augmented reality.

This app is called augmented reality, and what augmented reality is, is where you look at, with an iPad or an iPhone, and you look at a scene.

Then we overlay an animation or a picture into that scene to give you more information about that scene.

And I have kids that are very, very young.

And we realize that everybody spends more time on their phones when you go to a site or a visitors' experience.

And so this was more of a way to actually gain their knowledge and their interest in it.

So, we've spent a lot of time in developing the product and actually being able to bring in all the historical and bringing up the walls around us of the 1836 Alamo.

So, there are 14 sites that we've chosen around the Alamo Plaza that are significant in the telling of the story of the Alamo.

And one of those locations that we have is where you can stand and a portal will appear in front of you that's just a doorway.

And that doorway is into 1836.

And you can walk into that doorway, and once you're in there, you're in 1836 Alamo.

And as you spin around, all these buildings disappear, and you see the Alamo the way it was in 1836, to scale.

So, if you're standing next to the long barracks over there -- That used to be 23 feet high.

And when you're standing there and you look up, it goes up 23 feet high.

And you can see the clouds above and all that, and you can see the whole structure of the way it used to be.

And then you can look over here and this is where the palisade was and this is where Davy Crockett defended the Alamo.

And we can watch that happen.

And so in each of these places, we can go around and we can see exactly what it was like in 1836.

And then we also have a feature where you can step on a little pad on the ground and it's an elevator and it takes you up above and you get a bird's-eye view of the battle happening below you.

I think this is a way to better understand the Plaza in all of its historical layers.

And I don't worry about it devaluing the original.

People still want to see it.

People used to see pictures.

They would still come see it.

They would see movies.

They'd still come see it.

Now they'll be able to see three-dimensional, augmented reality on their screen at home.

They'll still want to come and see it and experience it here and know the places where the battle happened, where the Alamo Mission was.

I do believe that the time is already passed that our kids, our kids' kids -- the phone and the iPads and the devices that they have is already ingrained in them.

There's no way that we're gonna be able to backtrack from that.

And being able to provide a technology that really gives them history and other content in their phones is a plus.

I think it is a balancing act.

At a certain time, they need to look away from phones, but if we can actually give them history and additional good educational content through those devices, that's a good thing.

Well, I did a CD-ROM about the Alamo in '94, '95.

And it was a desktop application.

I was the first film production company to shoot inside the Alamo since 1906.

And it gave a really great history of the Alamo, but you could never get a feel for exactly being at the Alamo and seeing that happen.

But with augmented reality, you can stand at the place where the history happened, and you can see what it looked like and watch that battle unfold right there where it happened.

So, it makes it incredibly engaging and also expands your understanding of the site.

Knowing my kids, they actually have grown to enjoy history, but any time we actually go to actually see history or actually learn about it, their interest always gets distracted in looking at other things in the modern world.

So, being able to bring this to our home city -- The Alamo is something, you know, I've grown up with, and I've lived here all my life.

And to actually be able to translate that to them in a way that they really understand and really get excited about was a special thing to us.


And that wraps it up for this time.

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Until next time, I'm Hari Sreenivasan.

Thanks for watching.

Funding for this program is made possible by... ♪♪ ♪♪ ♪♪ ♪♪ ♪♪ ♪♪