Scientists discover mechanism that causes cancer cells to self-destruct


Many cancer patients struggle with the adverse effects of chemotherapy, still the most prescribed cancer treatment. For patients with pancreatic cancer and other aggressive cancers, the forecast is more grim: there is no known effective therapy.

A new Tel Aviv University study published last month in Oncotarget discloses the role of three proteins in killing fast-duplicating cancer cells while they’re dividing. The research, led by Prof. Malka Cohen-Armon of TAU’s Sackler School of Medicine, finds that these proteins can be specifically modified during the division process—mitosis—to unleash an inherent “death mechanism” that self-eradicates duplicating cancer cells.

“The discovery of an exclusive mechanism that kills cancer cells without impairing healthy cells, and the fact that this mechanism works on a variety of rapidly proliferating human cancer cells, is very exciting,” Prof. Cohen-Armon said. 
“According to the mechanism we discovered, the faster cancer cells proliferate, the faster and more efficiently they will be eradicated. The mechanism unleashed during mitosis may be suitable for treating aggressive cancers that are unaffected by traditional chemotherapy.

“Our experiments in cell cultures tested a variety of incurable human cancer types—breast, lung, ovary, colon, pancreas, blood, brain,” Prof. Cohen-Armon continued. “This discovery impacts existing cancer research by identifying a new specific target mechanism that exclusively and rapidly eradicates cancer cells without damaging normally proliferating human cells.”

The research was conducted in collaboration with Prof. Shai Izraeli and Dr. Talia Golan of the Cancer Research Center at Sheba Medical Center, Tel Hashomer, and Prof. Tamar Peretz, head of the Sharett Institute of Oncology at Hadassah Medical Center, Ein Kerem.

A new target for cancer research

The newly-discovered mechanism involves the modification of specific proteins that affect the construction and stability of the spindle, the microtubular structure that prepares duplicated chromosomes for segregation into “daughter” cells during cell division.

The researchers found that certain compounds called Phenanthridine derivatives were able to impair the activity of these proteins, which can distort the spindle structure and prevent the segregation of chromosomes. Once the proteins were modified, the cell was prevented from splitting, and this induced the cell’s rapid self-destruction.

“The mechanism we identified during the mitosis of cancer cells is specifically targeted by the Phenanthridine derivatives we tested,” Prof. Cohen-Armon said. “However, a variety of additional drugs that also modify these specific proteins may now be developed for cancer cell self-destruction during cell division. The faster the cancer cells proliferate, the more quickly they are expected to die.”

Research was conducted using both cancer cell cultures and mice transplanted with human cancer cells. The scientists harnessed biochemical, molecular biology and imaging technologies to observe the mechanism in real time. In addition, mice transplanted with triple negative breast cancer cells, currently resistant to available therapies, revealed the arrest of tumor growth.

“Identifying the mechanism and showing its relevance in treating developed tumors opens new avenues for the eradication of rapidly developing aggressive cancers without damaging healthy tissues,” said Prof. Cohen-Armon.
The researchers are currently investigating the potential of one of the Phenanthridine derivatives to treat two aggressive cancers known to be unresponsive to current chemotherapy: pancreatic cancer and triple negative breast cancer.

More information: Leonid Visochek et al, Exclusive destruction of mitotic spindles in human cancer cells, Oncotarget (2017). DOI: 10.18632/oncotarget.15343

Provided by: Tel Aviv University

Will Nanotechnology be the Answer for the Next Generation of Lithium-Ion Batteries?


Great Things from Small Things .. Nanotechnology Innovation

Nano LI Batt usc-lithium-ion-batteryDespite the recently reported battery-flaming problem of lithium-ion batteries (LIBs) in Boeing’s 787 Dreamliners and laptops (in 2006), LIBs are now successfully being used in many sectors. Consumer gadgets, electric cars, medical devices, space and military sectors use LIBs as portable power sources and in the future, spacecraft like James Webb Space Telescope are expected to use LIBs.

The main reason for this rapid domination of LIB technology in various sectors is that it has the highest electrical storage capacity with respect to its weight (one unit of LIB can replace two nickel-hydrogen battery units). Also, LIBs are suitable for applications where both high energy density and power density are required, and in this respect, they are superior to other types of rechargeable batteries such as lead-acid, nickel-cadmium, nickel-metal hydride, nickel-metal batteries, etc.

However, LIBs are required to improve in the following aspects: (i) store more energy and deliver higher…

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Supercapacitors and Li-ion Batteries in one Tidy Device


Great Things from Small Things .. Nanotechnology Innovation

Electronics-research-001A team of researchers at Rice University in the US has fabricated 3D nanostructured thin-film electrodes using tantalum oxide nanotubes and “carbon-onion”-coated iron oxide nanoparticles. The thin films appear to be excellent lithium-ion batteries while being good supercapacitors too. The devices might be ideal in next-generation hybrid energy-storage applications, including wearable “smart textiles”.

Electrochemical energy-storage devices such as Li-ion batteries (LIBs) and electrochemical supercapacitors (ECs) are currently the best option for powering portable electronics. Even better would be to combine the two types of device into one multifunctional electrode that combines the high energy density and capacity of Li-ion batteries with the high power density of supercapacitors. Capacitors are devices that store electric charge but ECs can store much more charge thanks to the double layer formed at an electrolyte-electrode interface when voltage is applied.

Until now, researchers have mainly studied carbon materials such as nanotubes and…

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Graphene/Nanotube Hybrid Benefits Flexible Solar Cells Applications for LOW Cost vs. Less Conversion Efficiency Required


Great Things from Small Things .. Nanotechnology Innovation

Rice logo_rice3Rice University scientists have invented a novel cathode that may make cheap, flexible dye-sensitized solar cells practical.

The Rice lab of materials scientist Jun Lou created the new cathode, one of the two electrodes in batteries, from nanotubes that are seamlessly bonded to graphene and replaces the expensive and brittle platinum-based materials often used in earlier versions.

The discovery was reported online in the Royal Society of Chemistry’s Journal of Materials Chemistry A.

Dye-sensitized solar cells have been in development since 1988 and have been the subject of countless high school chemistry class experiments. They employ cheap organic dyes, drawn from the likes of raspberries, which cover conductive titanium dioxide particles. The dyes absorb photons and produce electrons that flow out of the cell for use; a return line completes the circuit to the cathode that combines with an iodine-based electrolyte to refresh the dye.

CNT Solar 1-researchersu

While they are not…

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Tesla Honored As 2017’s ‘Battery Innovator Of The Year’ At The International Battery Seminar


tesla-honored-as-2017-s-battery-innovator-of-the-year-at-the-international-battery-seminarInternational experts in the field of battery research recognized Tesla’s contributions and cutting-edge innovations in battery technology. Tesla exec and battery expert says it’s all about implementation.  ( Tesla )

March 24, 2017

Tesla is always looking for ways to produce better energy storage not only to extend the range of its electric vehicles but also to power up homes using clean energy, and experts on battery technology have recognized the company’s efforts.

In a surprise addition to the 34th International Battery Seminar’s program, the organizers presented Kurt Kelty, Tesla’s senior director of Battery Technology with the “Battery Innovator of the Year” award, which he received on behalf of Tesla.

Tesla On Battery Technology

Kelty was scheduled to give the Plenary Keynote Address in front of 800 battery experts — including specialists from other EV manufacturers — at the International Battery Seminar, which was held from March 20 to 23 at Fort Lauderdale in Florida. However, before he was even able to utter his first sentence, the prestigious award was bestowed.

Kelty was quick to express his gratitude on behalf of Tesla and say how much of an honor the prize is for the company.

“Everyone recognizes we’re not a battery chemistry company. That’s not why we got the award. It’s more [about] the implementation of the technology,” Kelty said.

Tesla’s Battery Innovations

Tesla is not new to receiving awards when it comes to its battery technology. In 2016, Tesla’s top researcher on battery technology, Jeff Dahn, received the same award and the Gerhard Herzberg Canada Gold Medal for Science and Engineering for his research on lithium-ion batteries. And with the company’s smart energy storage solutions in response to energy crises and dedication to producing Li-ion batteries in its Gigafactory in Nevada in 2016 and early 2017, it’s not really that much of a surprise that Elon Musk’s company was honored this time around.

Tesla Will Continue To Innovate Batteries

In his keynote address, Kelty revealed that the company receives battery usage data from its electric vehicle and stationary unit customers in real-time and the company has been learning a lot from the collected data.

He also added that Telsa envisions a well-integrated clean energy system for homes, especially when users combine the company’s products together.

“Where we see the future [is] in houses [and] we want to be your EV provider. Put your EV in your garage and you charge it up with one of our chargers, you have a powerwall … [and] a solar product [solar roof] that we’ll be introducing this summer […] This is the kind of future we see for [your] house,” he reveals.

Musk is probably thrilled with the award but there’s no reaction yet from Tesla’s co-founder and Chief Executive Officer as of writing.

 

MIT: New kind of supercapacitor made without carbon


MIT-Supercapacitor_0 032417

To demonstrate the supercapacitor’s ability to store power, the researchers modified an off-the-shelf hand-crank flashlight (the red parts at each side) by cutting it in half and installing a small supercapacitor in the center, in a conventional button battery case, seen at top. When the crank is turned to provide power to the flashlight, the light continues to glow long after the cranking stops, thanks to the stored energy. Photo: Melanie Gonick

Energy storage device could deliver more power than current versions of this technology.

Energy storage devices called supercapacitors have become a hot area of research, in part because they can be charged rapidly and deliver intense bursts of power. However, all supercapacitors currently use components made of carbon, which require high temperatures and harsh chemicals to produce.

Now researchers at MIT and elsewhere have for the first time developed a supercapacitor that uses no conductive carbon at all, and that could potentially produce more power than existing versions of this technology.

The team’s findings are being reported in the journal Nature Materials, in a paper by Mircea Dincă, an MIT associate professor of chemistry; Yang Shao-Horn, the W.M. Keck Professor of Energy; and four others.

“We’ve found an entirely new class of materials for supercapacitors,” Dincă says.

Dincă and his team have been exploring for years a class of materials called metal-organic frameworks, or MOFs, which are extremely porous, sponge-like structures. These materials have an extraordinarily large surface area for their size, much greater than the carbon materials do. That is an essential characteristic for supercapacitors, whose performance depends on their surface area. But MOFs have a major drawback for such applications: They are not very electrically conductive, which is also an essential property for a material used in a capacitor.

“One of our long-term goals was to make these materials electrically conductive,” Dincă says, even though doing so “was thought to be extremely difficult, if not impossible.” But the material did exhibit another needed characteristic for such electrodes, which is that it conducts ions (atoms or molecules that carry a net electric charge) very well.

“All double-layer supercapacitors today are made from carbon,” Dincă says. “They use carbon nanotubes, graphene, activated carbon, all shapes and forms, but nothing else besides carbon. So this is the first noncarbon, electrical double-layer supercapacitor.”

One advantage of the material used in these experiments, technically known as Ni3(hexaiminotriphenylene)2, is that it can be made under much less harsh conditions than those needed for the carbon-based materials, which require very high temperatures above 800 degrees Celsius and strong reagent chemicals for pretreatment.

The team says supercapacitors, with their ability to store relatively large amounts of power, could play an important role in making renewable energy sources practical for widespread deployment. They could provide grid-scale storage that could help match usage times with generation times, for example, or be used in electric vehicles and other applications.

The new devices produced by the team, even without any optimization of their characteristics, already match or exceed the performance of existing carbon-based versions in key parameters, such as their ability to withstand large numbers of charge/discharge cycles. Tests showed they lost less than 10 percent of their performance after 10,000 cycles, which is comparable to existing commercial supercapacitors.

But that’s likely just the beginning, Dincă says. MOFs are a large class of materials whose characteristics can be tuned to a great extent by varying their chemical structure. Work on optimizing their molecular configurations to provide the most desirable attributes for this specific application is likely to lead to variations that could outperform any existing materials. “We have a new material to work with, and we haven’t optimized it at all,” he says. “It’s completely tunable, and that’s what’s exciting.”

While there has been much research on MOFs, most of it has been directed at uses that take advantage of the materials’ record porosity, such as for storage of gases. “Our lab’s discovery of highly electrically conductive MOFs opened up a whole new category of applications,” Dincă says. Besides the new supercapacitor uses, the conductive MOFs could be useful for making electrochromic windows, which can be darkened with the flip of a switch, and chemoresistive sensors, which could be useful for detecting trace amounts of chemicals for medical or security applications.

While the MOF material has advantages in the simplicity and potentially low cost of manufacturing, the materials used to make it are more expensive than conventional carbon-based materials, Dincă says. “Carbon is dirt cheap. It’s hard to find anything cheaper.” But even if the material ends up being more expensive, if its performance is significantly better than that of carbon-based materials, it could find useful applications, he says.

This discovery is “very significant, from both a scientific and applications point of view,” says Alexandru Vlad, a professor of chemistry at the Catholic University of Louvain in Belgium, who was not involved in this research. He adds that “the supercapacitor field was (but will not be anymore) dominated by activated carbons,” because of their very high surface area and conductivity. But now, “here is the breakthrough provided by Dinca et al.: They could design a MOF with high surface area and high electrical conductivity, and thus completely challenge the supercapacitor value chain! There is essentially no more need of carbons for this highly demanded technology.”

And a key advantage of that, he explains, is that “this work shows only the tip of the iceberg. With carbons we know pretty much everything, and the developments over the past years were modest and slow. But the MOF used by Dinca is one of the lowest-surface-area MOFs known, and some of these materials can reach up to three times more [surface area] than carbons. The capacity would then be astonishingly high, probably close to that of batteries, but with the power performance [the ability to deliver high power output] of supercapacitors.”

The research team included former MIT postdoc Dennis Sheberla (now a postdoc at Harvard University), MIT graduate student John Bachman, Joseph Elias PhD ’16, and Cheng-Jun Sun of Argonne National Laboratory. The work was supported by the U.S. Department of Energy through the Center for Excitonics, the Sloan Foundation, the Research Corporation for Science Advancement, 3M, and the National Science Foundation.

Powerful hybrid storage system combines advantages of lithium-ion batteries and Supercapacitors – “What Comes Next”


Bizzarrini-Veleno-future-Electric-Car-01

A battery that can be charged in seconds, has a large capacity and lasts ten to twelve years? Certainly, many have wanted such a thing. Now the FastStorageBW II project – which includes Fraunhofer – is working on making it a reality. Fraunhofer researchers are using pre-production to optimize large-scale production and ensure it follows the principles of Industrie 4.0 from the outset.

Imagine you’ve had a hectic day and then, to cap it all, you find that the battery of your electric vehicle is virtually empty. This means you’ll have to take a long break while it charges fully. It’s a completely different story with capacitors, which charge in seconds. However, they have a different drawback: they store very little energy.electric cars images

In the FastStorageBW II project, funded by the Baden-Württemberg Ministry of Economic Affairs, researchers from the Fraunhofer Institute for Manufacturing Engineering and Automation IPA in Stuttgart, together with colleagues from the battery manufacturer VARTA AG and other partners, are developing a powerful hybrid storage system that combines the advantages of lithium-ion batteries and .

“The PowerCaps have a specific capacity as high as lead batteries, a long life of ten to twelve years, and charge in a matter of seconds like a supercapacitor,” explains Joachim Montnacher, Head of the Energy business unit at Fraunhofer IPA. What’s more, PowerCaps can operate at temperatures of up to 85 degree Celsius. They withstand a hundred times more charge cycles than conventional battery systems and retain their charge over several weeks without any significant losses due to self-discharge.

Elon+Musk+cVLpwWp3rxJmAlso Read About: Supercapacitor breakthrough suggests EVs could charge in seconds but with a trade-off

“Supercapacitors may be providing an alternative to electric-car batteries sooner than expected, according to a new research study. Currently, supercapacitors can charge and discharge rapidly over very large numbers of cycles, but their poor energy density per kilogram —- at just one twentieth of existing battery technology — means that they can’t compete with batteries in most applications. That’s about to change, say researchers from the University of Surrey and University of Bristol in conjunction with Augmented Optics.

Large-scale production with minimum risk

The Fraunhofer IPA researchers’ main concern is with manufacturing: to set up new battery production, it is essential to implement the relevant process knowledge in the best possible way.

After all, it costs millions of euros to build a complete manufacturing unit. “We make it possible for battery manufacturers to install an intermediate step – a small-scale production of sorts – between laboratory production and large-scale production,” says Montnacher. “This way, we can create ideal conditions for large-scale production, optimize processes and ensure production follows the principles of Industrie 4.0 from the outset. Because in the end, that will give companies a competitive advantage.” Another benefit is that this cuts the time it takes to ramp up production by more than 50 percent.

For this innovative small-scale production setup, researchers cleverly combine certain production sequences. However, not all systems are connected to each other – at least, as far as the hardware is concerned. More often, it is an employee that carries the batches from one machine to the next. Ultimately, it is about developing a comprehensive understanding of the process, not about producing the greatest number of in the shortest amount of time. For example, this means clarifying questions such as if the desired quality can be reproduced. The systems are designed as flexibly as possible so that they can be used for different production variations.

Making large-scale production compatible with Industrie 4.0

As far as software is concerned, the systems are thoroughly connected. Like process clusters, they are also equipped with numerous sensors, which show the clusters what data to capture for each of the process steps. They communicate with one another and store the results in a cloud. Researchers and entrepreneurs can then use this data to quickly analyze which factors influence the quality of the product – Does it have Industrie 4.0 capability? Were the right sensors selected? Do they deliver the desired data? Where are adjustments required?

Fraunhofer IPA is also applying its expertise beyond the area of production technology: The scientists are developing business models for the marketing of cells, they are analyzing resource availability, and they are optimizing the subsequent recycling of PowerCaps.

Explore further: Virtual twin controls production

Provided by: Fraunhofer-Gesellschaft

Watch a YouTube Video in ‘Next Generation’ Energy-Dense Si-Nanowire Batteries

 

 

The Entrepreneur with the $100 Million Plan to Link Brains to Computers


keith-rankin-mit-header-compressor

Entrepreneur Bryan Johnson says he wanted to become very rich in order to do something great for humankind. Well …

Last year Johnson, founder of the online payments company Braintree, starting making news when he threw $100 million behind Kernel, a startup he founded to enhance human intelligence by developing brain implants capable of linking people’s thoughts to computers.

Johnson isn’t alone in believing that “neurotechnology” could be the next big thing. To many in Silicon Valley, the brain looks like an unconquered frontier whose importance dwarfs any achievement made in computing or the Web.

According to neuroscientists, several figures from the tech sector are currently scouring labs across the U.S. for technology that might fuse human and artificial intelligence. In addition to Johnson, Elon Musk has been teasing a project called “neural lace,” which he said at a 2016 conference will lead to “symbiosis with machines.” And Mark Zuckerberg declared in a 2015 Q&A that people will one day be able to share “full sensory and emotional experiences,” not just photos. Facebook has been hiring neuroscientists for an undisclosed project at Building 8, its secretive hardware division.

As these people see it, computing keeps achieving new heights, but our ability to interface with silicon is stuck in the keyboard era. Even when speaking to a computer program like Alexa or Siri, you can convey at most about 40 bits per second of information and only for short bursts. Compare that to data transfer records of a trillion bits per second along a fiber-optic cable.

“Ridiculously slow,” Musk complained.

But it turns out that connecting to the brain isn’t so easy. Six months after launching Kernel amid a media blitz, Johnson says he’s dropped his initial plans for a “memory implant,” switched scientific advisors, hired a new team, and decided to instead invest in developing a more general-purpose technology for recording and stimulating the brain using electrodes.

Johnson says the switch-up is part of trying something new. “If you look at the key contributing technologies of society, the ones with the most impact, like rockets, the Internet, biology—there was a transition point from academia to the private sector, and for the most part neuroscience hasn’t made that jump,” says Johnson. “The most critical element is timing, when is the right time to pursue this.”

Memory implants

After making a fortune selling Braintree to eBay for $800 million in 2013, Johnson, now 39, reportedly sought the advice of nearly 200 people on how to invest his new wealth. He settled on neurotechnology and, last August, he announced he’d create Kernel and build the first neural prosthetic for human intelligence enhancement.

But Johnson’s business plan was extremely vague; one scientist called it “metaphysical.” Kernel’s website was plastered with book-jacket-like endorsements from scientific celebrities including J. Craig Venter and Tim O’Reilly, extolling his “great” and “serious” commitment to understanding human intelligence, not to mention the impressive $100 million he later promised to invest in Kernel.

                                              

Bryan Johnson

The reality is that interfacing with the brain is tough: electronics irritate its tissue and stop working after a while, and no one will get brain surgery just in order to send an e-mail. What’s more, even if you can communicate with the brain, you might not know what it is saying.

“Billionaires entering the broader neurotechnology field are very optimistic and may overlook details of the problem, which is we are far away from meaningfully understanding the brain,” says Konrad Kording, a Northwestern University neuroscientist who has advised Johnson. “But neurotechnology allows you to work on the most interesting questions in the universe while potentially making money, and so that is exciting.”

Johnson’s persona is part buttoned-down Mormon missionary (he once was one), part hard-driving door-to-door credit-processing salesman (he was that too), but now, with his new wealth, he’s also taken on the mantle of a technology prophet. At a 2016 startup conference in Silicon Valley, he showed up with his hair unbrushed, wearing a T-shirt with holes in it, and gave a wide-ranging lecture on human tool use from prehistory into the present, arguing that now “our very existence is programmable” through biology and machine interfaces.

Kernel’s original technology was a memory prosthesis, developed by Theodore Berger of the University of Southern California, who until recently was also the company’s chief scientific officer. Berger’s technology (see “10 Breakthrough Technologies: Memory Implants”) is a way of recording memories of rats and monkeys, storing these patterns on a computer chip, and re-delivering them to the hippocampus. One version of the setup, Berger says, has been tested in a handful of human patients undergoing brain surgery for other reasons.

But a mere six months after starting Kernel, Berger is no longer part of the company, and memory implants are no longer part of Kernel’s near-term plans. Johnson and Berger both confirmed the separation.

Berger’s vision, according to several people, was too complex, too speculative, and too far from becoming a medical reality, while Johnson hoped to see a return on his investment sometime soon. “They have a new direction, but we’re still talking,” says Berger. “The basic reason is it was going to take too long. It’s one thing to think about this and quite another to do it.”

Johnson says he concluded that Berger’s work “is really interesting, but not an entry point” into a commercially viable business.

Brain interface

brain-quantum-1-download (1)

Read More: “Its’ All in Our Heads … “

By last November, Johnson was already exploring a pivot for his company, meeting with Christian Wentz, head of a small Cambridge startup, Kendall Research Systems, that sells equipment for recording in the neurons of mice and other animals. The company spun out of the laboratory of Edward Boyden, a professor at MIT who invents new ways of analyzing brain tissue.

In February, Johnson acquired Wentz’s company (for an undisclosed sum) and with it brought in a new team, including Wentz and Adam Marblestone, a noted theorist of both the limitations and possibilities of brain interfaces, who will become chief strategy officer. Both are former Boyden lab members, as are two other Kernel scientists, Caroline Moore-Kochlacs and Jake Bernstein.

Johnson says Kernel will now develop a “generalized human electrophysiology platform”—that is, a flexible way of measuring the electrical impulses from many neurons at once, and stimulating them, too. The eventual objective is to use such electronics to treat major diseases, like depression or Alzheimer’s. “It’s for clinical use,” he says. “We are a for-profit company.”

Wentz says as part of the acquisition he and Johnson agreed that much more R&D on brain interfaces will probably be needed. “We have a very sober view of what can and can’t be done,” Wentz says. “We are not naïve.” He calls Kernel’s effort a “15-year endeavor,” although he adds that “we want to do in that period what has been done in the last 100 years.”

With the pivot, Johnson is effectively jumping on an opportunity created by the Brain Initiative, an Obama-era project which plowed money into new schemes for recording neurons. That influx of cash has spurred the formation of several other startups, including Paradromics and Cortera, also developing novel hardware for collecting brain signals. As part of the government brain project, the defense R&D agency DARPA says it is close to announcing $60 million in contracts under a program to create a “high-fidelity” brain interface able to simultaneously record from one million neurons (the current record is about 200) and stimulate 100,000 at a time.

“It’s time for neuroscience to graduate from academia to a general neuroscience platform,” says Johnson. With such a technology “a whole range of new applications—a lot of white space—would open up.”

Johnson declined to describe the specifics of Kernel’s technological approach to connecting with the brain, as did Boyden and Wentz. However, the team members have been working on well-identified problems. Wentz has been involved with developing electronics for high-speed reading of data emitted by wireless implants. Already, the flow of information that can be collected from a mouse’s brain in real time outruns what a laptop computer can handle. The team also needs a way to interface with the human brain. Boyden’s lab has worked on several concepts to do so, including needle-shaped probes with tiny electrodes etched onto their surface. Another idea is to record neural activity by threading tiny optical fibers through the brain’s capillaries, an idea roughly similar to Musk’s neural lace.

More sophisticated means of reading and writing to the brain are seen as potential ways to treat psychiatric disorders. Under a concept that Boyden calls “brain coprocessors,” it may be possible to create closed-loop systems that detect certain brain signals—say, those associated with depression—and shock the brain to reverse them. Some surgeons and doctors funded by another DARPA program are in the early stages of determining whether serious mental conditions can be treated in this way (see “A Shocking Way to Fix the Brain”).

Boyden says Johnson’s $100 million makes a big difference to how he and his students view the entrepreneur’s goals. “A lot of neurotechnology has come and gone. But one thing is that it’s very expensive,” he says. “The inventing is expensive, the clinical work is expensive. It’s not easy. And here is someone putting money into the game.”

Solar cells and photodetectors based on tunable nanoparticles (Quantum Dots)



A femtosecond laser pulse launches a photocurrent transient in a quantum dot solid, which is time-resolved using ultrafast sampling electronics. This technique provides unprecedented insights into early time photoconductance in quantum dot assemblies for solar cells and photodetectors. Credit: Los Alamos National Laboratory

Solar cells and photodetectors could soon be made from new types of materials based on semiconductor quantum dots, thanks to new insights based on ultrafast measurements capturing real-time photoconversion processes.
“Our latest ultrafast electro-optical spectroscopy studies provide unprecedented insights into the photophysics of quantum dots,” said lead researcher Victor Klimov, a physicist specializing in semiconductor nanocrystals at Los Alamos National Laboratory, “and this new information helps perfect the materials’ properties for applications in practical photoconversion devices.

Our new experimental technique allows us to follow a chain of events launched by femtosecond laser pulses and pin down processes responsible for efficiency losses during transformation of incident light into electrical current.”

Photoconversion is a process wherein the energy of a photon, or quantum of light, is converted into other forms of energy, for example, chemical or electrical.

Semiconductor quantum dots are chemically synthesized crystalline nanoparticles that have been studied for more than three decades in the context of various photoconversion schemes including photovoltaics (generation of photo-electricity) and photo-catalysis (generation of “solar fuels”). 



The appeal of quantum dots comes from the unmatched tunability of their physical properties, which can be adjusted by controlling the size, shape and composition of the dots.

At Los Alamos, the research connects to the institutional mission of solving national security challenges through scientific excellence, in this case focusing on novel physical principles for highly efficient photoconversion, charge manipulation in exploratory device structures and novel nanomaterials.

See a video on Quantum Dots



The interest in quantum dots as solar-cell materials has been motivated by their tunable optical spectra as well as interesting new physics such as high-efficiency carrier multiplication, that is, generation of multiple electron-hole pairs by single photons.

This effect, discovered by Los Alamos researchers in 2004, resulted in the surge of activities in the area of quantum dot solar cells that quickly pushed the efficiencies of practical devices to more than 10 percent.

Further progress in this area has been by hindered by the challenge of understanding the mechanisms of electrical conductance in quantum dot solids and the processes that limit the charge transport distance.

One specific and persistent challenge of great importance from the standpoint of photovoltaic (PV) applications, Klimov said, is understanding the reasons underlying a considerable loss in photovoltage compared to predicted theoretical limits—a problem with quantum dot solar cells known as a “photovoltage deficit.” Los Alamos researchers at the Center for Advanced Solar Photophysics (CASP) helps answer some of the above questions.

By applying a combination of ultrafast optical and electrical techniques, the Los Alamos scientists have been able to resolve step-by-step a sequence of events involved in photoconversion in quantum dot films from generation of an exciton to electron-hole separation, dot-to-dot charge migration and finally recombination.

The high temporal resolution of these measurements (better than one billionth of a second) enabled the team to reveal the cause of a large drop of the electron energy, which results from very fast electron trapping by defect-related states.

In the case of practical devices, this process would result in reduced photovoltage. The newly conducted studies establish the exact time scale of this problematic trapping process and suggest that a moderate (less than ten-fold) improvement in the electron mobility should allow for collecting photogenerated charge carriers prior to their relaxation into lower-energy states.

This would produce a dramatic boost in the photovoltage and therefore increase the overall device efficiency.



Another interesting effect revealed by these studies is the influence of electron and hole “spins” on photoconductance. Usually spin properties of particles (they can be thought of as the rate and direction of particle rotation around its axis) are invoked in the case of interactions with a magnetic field.

However, previously it was found that even a weak interaction between spins of an electron and a hole (so-called “spin-exchange” interaction) has a dramatic effect on light emission from the quantum dots.

The present measurements reveal that these interactions also affect the process of electron-hole separation between adjacent dots in quantum-dot solids. Specifically these studies suggest that future efforts on high-sensitivity quantum-dot photodetectors should take into consideration the effect of exchange blockade, which otherwise might inhibit low-temperature photoconductance.

Quantum dot materials have been at the heart of research at the Los Alamos Center for Advanced Solar Photophysics, which has investigated their application to solar-energy technologies such as luminescent sunlight collectors for solar windows and low-cost PV cells processed from quantum dot solutions.
More information: Andrew F. Fidler et al, Electron–hole exchange blockade and memory-less recombination in photoexcited films of colloidal quantum dots, Nature Physics (2017). DOI: 10.1038/nphys4073

R. D. Schaller et al. High Efficiency Carrier Multiplication in PbSe Nanocrystals: Implications for Solar Energy Conversion, Physical Review Letters (2004). DOI: 10.1103/PhysRevLett.92.186601

Provided by: Los Alamos National Laboratory

Using Nanotechnology to Make Solar Cells 2X more Efficient 



In the future, solar cells can become twice as efficient by employing a few smart little nano-tricks.

Researchers are currently developing the environment-friendly solar cells of the future, which will capture twice as much energy as the cells of today. The trick is to combine two different types of solar cells in order to utilize a much greater portion of the sunlight.

“These are going to be the world’s most efficient and environment-friendly solar cells. There are currently solar cells that are certainly just as efficient, but they are both expensive and toxic. 

Furthermore, the materials in our solar cells are readily available in large quantities on Earth. That is an important point,” says Professor 


Bengt Svensson of the Department of Physics at the University of Oslo (UiO) and Centre for Materials Science and Nanotechnology (SMN).
Svensson is one of Norway’s leading researchers on solar energy, and for many years, he has headed major research projects at the Micro and Nanotechnology Laboratory (MiNaLab), which is jointly owned by UiO and the Foundation for Scientific and Industrial Research at the Norwegian Institute of Technology (Sintef). 

Using nanotechnology, atoms and molecules can be combined into new materials with very special properties.

The physicists are now making use of the very best of nanotechnology and will develop new solar cells in the European research project, Solhet (High-performance tandem heterojunction solar cells for specific applications), which is a collaborative project involving UiO, the Institute for Energy Technology (IFE) at Kjeller, Norway and the University Polytehnica of Bucharest, together with two other Romanian institutions. 


The Solhet team at UiO comprises Raj Kumar (Post-doctor), Kristin Bergum (Researcher), Edouard Monakhov (professor) and Svensson.

Modern solar cells

Their goal is to utilize even more of the spectrum of sunlight than is possible at present. Ninety-nine per cent of today’s solar cells are made from silicon, which is one of the most common elements on Earth. Unfortunately, silicon solar cells only utilize 20 per cent of the sunlight. 

The world record is 25 per cent, but these solar cells are laced with rare materials that are also toxic. The theoretical limit is 30 per cent. The explanation for this limit is that silicon cells primarily capture the light waves from the red spectrum of sunlight. That means that most of the light waves remain unutilized.

The new solar cells will be composed of two energy-capturing layers. The first layer will still be composed of silicon cells.

“The red wavelengths of sunlight generate electricity in the silicon cells in a highly efficient manner. We’ve done a great deal of work with silicon, so there is only a little more to gain.”

The new trick is to add another layer on top of the silicon cells. This layer is composed of copper oxide and is supposed to capture the light waves from the blue spectrum of sunlight.

“We have managed to produce a copper oxide layer that captures three per cent of the energy from the sunlight. The world record is nine per cent. We are currently working intensely to increase that percentage to twenty per cent. The combination of silicon cells in the one layer and copper oxide cells in the other means that we’ll be able to absorb far more light and thereby reduce the energy loss. With this combination, we can utilize 35 to 40 per cent of the sunlight,” emphasizes Bengt Svensson.

There will also be other layers in the solar cell panel. On the back surface, a protective glass layer will be deposited, along with a metal layer that conducts the electricity out of the solar cell. The front side will have an antireflective coating, so that the light rays are captured rather than reflected away.

The solar cell panel will be very thin. The thickness of the individual layers will vary between a hundred and a thousand nanometres. A thousand nanometres equals one micrometre. A single hair is ten times thicker. One of the trickiest moves is to create a special layer that will be as thin as one to two nanometres. Apollon will have more to say about that, but first a few theoretical explanations are in order.

Create conducting electrons

All solar cell materials are composed of semiconductor materials. Semiconductors have very special electrical properties. These electrical properties are determined by the band gap.

The band gap gives an indication of how much energy will be required in order to create conducting electrons.

Materials without any band gap width conduct electricity. Materials with a big band gap do not conduct electricity. Semiconductors are materials with a moderate band gap, which means that they only partially conduct electricity.

Nanotechnology is used to design materials with a very specific band gap.

When the photons, i.e. light particles from the sun, strike the solar cell, energy is delivered to the solar cell. This energy impels an electron through the band gap and into what is called the conduction band, where the electrons can be gathered up and removed as energy.

The electrons leave behind electron holes. Both the electron and the electron hole can conduct electricity.

“The challenge is to develop cobber oxide with a band gap that is precisely large enough so that the electrons can be captured before they fall back down to their electron holes. We’ve been working on this for a number of years, and we are beginning to understand how this can be done.”

Although time is scarce, there is a ray of light: if the electrons are removed from the electron holes for more than a millisecond, it is possible to capture them.

Chaos between the layers

One of the unsolved problems in the new solar cells is the boundary areas between the different layers.

“When the layers are deposited on top of each other, chemical reactions take place that reduce or in the worst case destroy the solar cells.”

One problem is the boundary surface between the solar cell layer that captures energy from the blue light and the outermost layer of zinc oxide that both protects the cell and conducts the electricity out of the cell. Unfortunately, the electrons die at this boundary surface.

The biggest challenge is the boundary surface between the silicon layer, which captures energy from the red light, and the copper oxide layer, which captures energy from the blue light.

The two solar cell layers each function well on their own, and that is where Apollon gets to the point. The problem arises when the layers are deposited together. That is when the adverse chemical changes occur.

“The chemical changes can change the band gap. When the band gap is wrong or defective, the electron holes are filled again before the electrons can be captured.”

One possibility is to deposit other substances between the layers so that the chemical changes are minimized.

There are many ways to create this buffer layer.

“We want to use a hydrogen-rich material. That can pacify the chemical changes and increase the lifetime of the electrons and electron holes.”

Another possibility is to lace the buffer with gallium oxide, but this substance is not exactly environment-friendly. Pure gallium is toxic.

By making the buffer as thin as just one to two nanometres, the chemical effect is minimized.

“The thicker the intermediate layer, the more electrons will be inhibited underway. That destroys the electrical capacity. If the electrons are inhibited in the buffer layer, the solar cells no longer function.”

From theory to practice

The theoretical modelling about how the buffer layer ought to appear is done at the University Polytehnica in Bucharest.

“They are very good at theoretical modelling,” says Bengt Svensson.

Professor Laurentiu Fara at the University Polytehnica in Bucharest tells Apollon that, among other things, they have calculated and simulated the optimal thickness of the solar cell layers, the best possible way for the layers to be deposited together, and how it is theoretically possible to extract the greatest possible amount of electricity.

“We have great expectations that the solar cells can become reliable and profitable, but we’re very aware that a great deal of hard work still remains,” emphasizes Laurentiu Fara.

UiO is performing the experimental part of the work. IFE will develop the prototype for producing the solar cells in great volumes. In addition, IFE is the main coordinator for the whole research project.

“We have already worked with silicon-based solar cell technology for many years in collaboration with the Norwegian solar cell industry. Now we’ll look into how the two solar cell layers can be adapted to each other in order to get the greatest amount of power out of the whole solar cell and into how the two cells affect each other both optically and electrically,” say Sean Erik Foss and Ørnulf Nordseth at IFE.

They tell us that very many researchers and technology firms are working now on the new type of solar cells with silicon in the bottom layer and a layer of “more exotic materials” on top.

The Romanian solar cell company, Wattrom, intends to show that it is possible to manufacture the new solar cells.

“The technology is inexpensive, it can easily be scaled up to large volumes, and it’s not more expensive to produce solar cells out of copper oxide than out of silicon,” says Bengt Svensson.

He thinks the solar cells will be very profitable to produce because the utilization of the light spectrum will be high.

“Even a tenth of a per cent increase in the efficiency yields substantial economic gains for the solar cell industry, but we’re talking here about a much more dramatic increase in efficiency.”

Moreover, the solar cells will function well even in those parts of the globe where the sun is low on the horizon, such as Scandinavia.

He says that efficient solar cells can change the whole way of thinking about energy in the future.

“We have an enormous resource in the sun. If we could utilize the sunlight one hundred per cent, an hour of the annual sunlight would meet all the energy needs on Earth. Thus, the potential is enormous. In principle, it is possible to meet the whole world’s energy needs with sunlight. Solar energy is actually the renewable energy source that has the greatest potential of all. That is what we want to utilize,” says Bengt Svensson.

Source: By Yngve Vogt, University of Oslo

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