Rutgers University – Alzheimer’s may be linked to defective brain cells spreading disease


Rutgers scientists say neurodegenerative diseases like Alzheimer’s and Parkinson’s may be linked to defective brain cells disposing toxic proteins that make neighboring cells sick

In a study published in Nature, Monica Driscoll, distinguished professor of molecular biology and biochemistry, School of Arts and Sciences, and her team, found that while healthy neurons should be able to sort out and and rid brain cells of toxic proteins and damaged cell structures without causing problems, laboratory findings indicate that it does not always occur.

These findings, Driscoll said, could have major implications for neurological disease in humans and possibly be the way that disease can spread in the brain.

“Normally the process of throwing out this trash would be a good thing,” said Driscoll. “But we think with neurodegenerative diseases like Alzheimer’s and Parkinson’s there might be a mismanagement of this very important process that is supposed to protect neurons but, instead, is doing harm to neighbor cells.”

Driscoll said scientists have understood how the process of eliminating toxic cellular substances works internally within the cell, comparing it to a garbage disposal getting rid of waste, but they did not know how cells released the garbage externally.

“What we found out could be compared to a person collecting trash and putting it outside for garbage day,” said Driscoll. “They actively select and sort the trash from the good stuff, but if it’s not picked up, the garbage can cause real problems.”

Working with the transparent roundworm, known as the C. elegans, which are similar in molecular form, function and genetics to those of humans, Driscoll and her team discovered that the worms — which have a lifespan of about three weeks — had an external garbage removal mechanism and were disposing these toxic proteins outside the cell as well.

Ilija Melentijevic, a graduate student in Driscoll’s laboratory and the lead author of the study, realized what was occurring when he observed a small cloud-like, bright blob forming outside of the cell in some of the worms. Over two years, he counted and monitored their production and degradation in single still images until finally he caught one in mid-formation.

“They were very dynamic,” said Melentijevic, an undergraduate student at the time who spent three nights in the lab taking photos of the process viewed through a microscope every 15 minutes. “You couldn’t see them often, and when they did occur, they were gone the next day.”

Research using roundworms has provided scientists with important information on aging, which would be difficult to conduct in people and other organisms that have long life spans.

In the newly published study, the Rutgers team found that roundworms engineered to produce human disease proteins associated with Huntington’s disease and Alzheimer’s, threw out more trash consisting of these neurodegenerative toxic materials.

While neighboring cells degraded some of the material, more distant cells scavenged other portions of the diseased proteins.

“These finding are significant,” said Driscoll. The work in the little worm may open the door to much needed approaches to addressing neurodegeneration and diseases like Alzheimer’s and Parkinson’s.”

Story Source:

Materials provided by Rutgers University. Original written by Robin Lally. Note: Content may be edited for style and length.


Journal Reference:

  1. Ilija Melentijevic, Marton L. Toth, Meghan L. Arnold, Ryan J. Guasp, Girish Harinath, Ken C. Nguyen, Daniel Taub, J. Alex Parker, Christian Neri, Christopher V. Gabel, David H. Hall, Monica Driscoll. C. elegans neurons jettison protein aggregates and mitochondria under neurotoxic stress. Nature, 2017; DOI: 10.1038/nature21362

Cite This Page:

Rutgers University. “Alzheimer’s may be linked to defective brain cells spreading disease: Study finds toxic proteins doing harm to neighboring neurons.” ScienceDaily. ScienceDaily, 10 February 2017. <www.sciencedaily.com/releases/2017/02/170210131016.htm>.
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Cornell University: Pore size influences nature of complex nanostructures – Materials for energy storage, biochemical sensors and electronics


The mere presence of void or empty spaces in porous two-dimensional molecules and materials leads to markedly different van der Waals interactions across a range of distances. Credit: Yan Yang and Robert DiStasio

Building at the nanoscale is not like building a house. Scientists often start with two-dimensional molecular layers and combine them to form complex three-dimensional architectures.

And instead of nails and screws, these structures are joined together by the attractive van der Waals forces that exist between objects at the nanoscale.

Van der Waals forces are critical in constructing  for energy storage, biochemical sensors and electronics, although they are weak when compared to chemical bonds. They also play a crucial role in , determining which drugs bind to the active sites in proteins.

In new research that could help inform development of new materials, Cornell chemists have found that the empty space (“pores”) present in two-dimensional molecular building blocks fundamentally changes the strength of these van der Waals forces, and can potentially alter the assembly of sophisticated nanostructures.

The findings represent an unexplored avenue toward governing the self-assembly of complex nanostructures from porous two-dimensional building blocks.

“We hope that a more complete understanding of these forces will aid in the discovery and development of novel materials with diverse functionalities, targeted properties, and potentially novel applications,” said Robert A. DiStasio Jr., assistant professor of chemistry in the College of Arts and Sciences.

In a paper titled “Influence of Pore Size on the van der Waals Interaction in Two-Dimensional Molecules and Materials,” published Jan. 14 in Physical Review Letters, DiStasio, graduate student Yan Yang and postdoctoral associate Ka Un Lao describe a series of mathematical models that address the question of how void space fundamentally affects the attractive physical forces which occur over nanoscale distances.

In three prototypical model systems, the researchers found that particular pore sizes lead to unexpected behavior in the  that govern van der Waals forces.

Further, they write, this behavior “can be tuned by varying the relative size and shape of these void spaces … [providing] new insight into the self-assembly and design of complex nanostructures.”

While strong covalent bonds are responsible for the formation of two-dimensional molecular layers, van der Waals interactions provide the main attractive  between the layers. As such, van der Waals forces are largely responsible for the self-assembly of the complex three-dimensional nanostructures that make up many of the advanced materials in use today.

The researchers demonstrated their findings with numerous two-dimensional systems, including covalent organic frameworks, which are endowed with adjustable and potentially very large pores.

“I am surprised that the complicated relationship between void space and van der Waals forces could be rationalized through such simple models,” said Yang. “In the same breath, I am really excited about our findings, as even  in the van der Waals forces can markedly impact the properties of molecules and materials.”

Explore further: Researchers refute textbook knowledge in molecular interactions

More information: Yan Yang et al, Influence of Pore Size on the van der Waals Interaction in Two-Dimensional Molecules and Materials, Physical Review Letters (2019).  DOI: 10.1103/PhysRevLett.122.026001 

Boosting lithium ion batteries capacity 10X with Tiny Silicon Particles – University of Alberta


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U of Alberta chemists Jillian Buriak, Jonathan Veinot and their team found that nano-sized silicon particles overcome a limitation of using silicon in lithium ion batteries. The discovery could lead to a new generation of batteries …more

University of Alberta chemists have taken a critical step toward creating a new generation of silicon-based lithium ion batteries with 10 times the charge capacity of current cells.

“We wanted to test how different sizes of  nanoparticles could affect fracturing inside these batteries,” said Jillian Buriak, a U of A chemist and Canada Research Chair in Nanomaterials for Energy. ua buriak tinysiliconp

Silicon shows promise for building much higher-capacity batteries because it’s abundant and can absorb much more lithium than the graphite used in current lithium ion batteries. The problem is that silicon is prone to fracturing and breaking after numerous charge-and-discharge cycles, because it expands and contracts as it absorbs and releases lithium ions.

Existing research shows that shaping silicon into nano-scale particles, wires or tubes helps prevent it from breaking. What Buriak, fellow U of A chemist Jonathan Veinot and their team wanted to know was what size these structures needed to be to maximize the benefits of silicon while minimizing the drawbacks.

The researchers examined silicon nanoparticles of four different sizes, evenly dispersed within highly conductive graphene aerogels, made of carbon with nanoscopic pores, to compensate for silicon’s low conductivity. They found that the smallest particles—just three billionths of a metre in diameter—showed the best long-term stability after many charging and discharging cycles.

“As the particles get smaller, we found they are better able to manage the strain that occurs as the silicon ‘breathes’ upon alloying and dealloying with , upon cycling,” explained Buriak.

u of alberta imagesThe research has potential applications in “anything that relies upon  using a battery,” said Veinot, who is the director of the ATUMS graduate student training program that partially supported the research.

“Imagine a car having the same size battery as a Tesla that could travel 10 times farther or you charge 10 times less frequently, or the battery is 10 times lighter.”

Veinot said the next steps are to develop a faster, less expensive way to create  to make them more accessible for industry and technology developers.

The study, “Size and Surface Effects of Silicon Nanocrystals in Graphene Aerogel Composite Anodes for Lithium Ion Batteries,” was published in Chemistry of Materials.

 Explore further: Toward cost-effective solutions for next-generation consumer electronics, electric vehicles and power grids

More information: Maryam Aghajamali et al. Size and Surface Effects of Silicon Nanocrystals in Graphene Aerogel Composite Anodes for Lithium Ion Batteries, Chemistry of Materials (2018). DOI: 10.1021/acs.chemmater.8b03198

Watch a YouTube Video about an Energy Storage Company Tenka Energy, Inc., that has developed and prototyped the NextGen of silicon-lithium-ion batteries for EV’s, Drones, Medical Sensors ….

Tenka Energy, Inc. Building Ultra-Thin Energy Dense SuperCaps and NexGen Nano-Enabled Pouch & Cylindrical Batteries – Energy Storage Made Small and POWERFUL!

via @Genesisnanotech #greatthingsfromsmallthings #energystorage

Ultra ultrasound to revolutionize Technology – From Medical Devices to Unmanned Vehicles


ultraultraso    Credit: University of Queensland

A new and extremely sensitive method of measuring ultrasound could revolutionise everything from medical devices to unmanned vehicles.

Researchers at The University of Queensland have combined modern nanofabrication and nanophotonics techniques to build the ultraprecise  sensors on a silicon chip.

Professor Warwick Bowen, from UQ’s Precision Sensing Initiative and the Australian Centre for Engineered Quantum Systems, said the development could usher in a host of exciting new technologies.

“This is a major step forward, since accurate ultrasound measurement is critical for a range of applications,” he said.

“Ultrasound is used for medical ultrasound, often to examine , as well as for  biomedical imaging to detect tumours and other anomalies.

“It’s also commonly used for spatial applications, like in the sonar imaging of underwater objects or in the navigation of unmanned aerial vehicles.

“Improving these applications requires smaller, higher precision sensors and, with this new technique, that’s exactly what we’ve been able to develop.”

The technology is so sensitive that it can hear, for the first time, the miniscule random forces from surrounding air molecules.

“We’ve developed a near perfect ultrasound detector, hitting the limits of what the technology is capable of achieving,” Professor Bowen said.

“We’re now able to measure ultrasound waves that apply tiny forces – comparable to the gravitational force on a virus – and we can do this with sensors smaller than a millimetre across.”

Research leader Dr. Sahar Basiri-Esfahani, now at Swansea University, said the accuracy of the  could change how scientists understand biology.

“We’ll soon have the ability to listen to the sound emitted by living bacteria and cells,” she said.

“This could fundamentally improve our understanding of how these small biological systems function.

“A deeper understanding of these biological systems may lead to new treatments, so we’re looking forward to seeing what future applications emerge.”

The research is published in Nature Communications.

 Explore further: Miniaturised pipe organ could aid medical imaging

More information: Sahar Basiri-Esfahani et al. Precision ultrasound sensing on a chip, Nature Communications (2019). DOI: 10.1038/s41467-018-08038-4

 

New Cancer Research – Converting Cancer Cells to Fat Cells to Stop Cancer’s Spread


A method for fooling breast cancer cells into fat cells has been discovered by researchers from the University of Basel.

The team were able to transform EMT-derived breast cancer cells into fat cells in a mouse model of the disease – preventing the formation of metastases. The proof-of-concept study was published in the journal Cancer Cell. 

Malignant cells can rapidly respond and adapt to changing microenvironmental conditions, by reactivating a cellular process called epithelial-mesenchymal transition (EMT), enabling them to alter their molecular properties and transdifferentiate into a different type of cell (cellular plasticity).

Senior author of the study Gerhard Christofori, professor of biochemistry at the University of Basel, commented in a recent press release: “The breast cancer cells that underwent an EMT not only differentiated into fat cells, but also completely stopped proliferating.”

“As far as we can tell from long-term culture experiments, the cancer cells-turned-fat cells remain fat cells and do not revert back to breast cancer cells,” he explained.

Epithelial-mesenchymal transition and cancer 

Cancer cells can exploit EMT – a process that is usually associated with the development of organs during embryogenesis – in order to migrate away from the primary tumor and form secondary metastases. Cellular plasticity is linked to cancer survival, invasion, tumor heterogeneity and resistance to both chemo and targeted therapies. In addition, EMT and the inverse process termed mesenchymal-epithelial transition (MET) both play a role in a cancer cell’s ability to metastasize.

Using mouse models of both murine and human breast cancer the team investigated whether they could therapeutically target cancer cells during the process of EMT – whilst the cells are in a highly plastic state. When the mice were administered Rosiglitazone in combination with MEK inhibitors it provoked the transformation of the cancer cells into post-mitotic and functional adipocytes (fat cells). In addition, primary tumor growth was suppressed and metastasis was prevented. 

Cancer cells marked in green and a fat cell marked in red on the surface of a tumor (left). After treatment (right), three former cancer cells have been converted into fat cells. The combined marking in green and red causes them to appear dark yellow. Credit: University of Basel, Department of Biomedicine

Christofori highlights the two major findings in the study: 

“Firstly, we demonstrate that breast cancer cells that undergo an EMT and thus become malignant, metastatic and therapy-resistant, exhibit a high degree of stemness, also referred to as plasticity. It is thus possible to convert these malignant cells into other cell types, as shown here by a conversion to adipocytes.”

“Secondly, the conversion of malignant breast cancer cells into adipocytes not only changes their differentiation status but also represses their invasive properties and thus metastasis formation and their proliferation. Note that adipocytes do not proliferate anymore, they are called ‘post-mitotic’, hence the therapeutic effect.”

Since both drugs used in the preclinical study were FDA-approved the team are hopeful that it may be possible to translate this therapeutic approach to the clinic. 

“Since in patients this approach could only be tested in combination with conventional chemotherapy, the next steps will be to assess in mouse models of breast cancer whether and how this trans-differentiation therapy approach synergizes with conventional chemotherapy. In addition, we will test whether the approach is also applicable to other cancer types. These studies will be continued in our laboratories in the near future.”

Journal Reference: Ronen et al. Gain Fat–Lose Metastasis: Converting Invasive Breast Cancer Cells into Adipocytes Inhibits Cancer Metastasis. Cancer Cell. (2019). Available at: https://www.cell.com/cancer-cell/fulltext/S1535-6108(18)30573-7&nbsp;

Gerhard Christofori was speaking to Laura Elizabeth Lansdowne, Science Writer for Technology Networks

Brookhaven National Laboratory – Searching for More Cost Efficient Catalysts for Hydrogen Fuel Cells – Illuminating Nanoparticle Growth With X-Rays


brookhaven fuel cell research 189306_web
Brookhaven Lab scientists Mingyuan Ge, Iradwikanari Waluyo, and Adrian Hunt are pictured left to right at the IOS beamline, where they studied the growth pathway of an efficient catalyst for hydrogen fuel cells. Credit: Brookhaven National Laboratory

Hydrogen fuel cells are a promising technology for producing clean and renewable energy, but the cost and activity of their cathode materials is a major challenge for commercialization. Many fuel cells require expensive platinum-based catalysts–substances that initiate and speed up chemical reactions–to help convert renewable fuels into electrical energy. To make hydrogen fuel cells commercially viable, scientists are searching for more affordable catalysts that provide the same efficiency as pure platinum.

“Like a battery, hydrogen fuel cells convert stored chemical energy into electricity. The difference is that you’re using a replenishable fuel so, in principle, that ‘battery’ would last forever,” said Adrian Hunt, a scientist at the National Synchrotron Light Source II(NSLS-II), a U.S. Department of Energy (DOE) Office of Science User Facility at DOE’s Brookhaven National Laboratory. “Finding a cheap and effective catalyst for hydrogen fuel cells is basically the holy grail for making this technology more feasible.”

Taking part in this worldwide search for fuel cell cathode materials, researchers at the University of Akron developed a new method of synthesizing catalysts from a combination of metals–platinum and nickel–that form octahedral (eight-sided) shaped nanoparticles. While scientists have identified this catalyst as one of the most efficient replacements for pure platinum, they have not fully understood why it grows in an octahedral shape. To better understand the growth process, the researchers at the University of Akron collaborated with multiple institutions, including Brookhaven and its NSLS-II.

brookhaven fc 6-scientistsbo

Schematic diagram of the oxygen reduction reaction (reduction of O2 into H2O) on the Pt(110) surface of the PtPb/Pt nanoplates, with purple representing Pt atoms and orange representing Pb atoms. Credit: Brookhaven National Laboratory

“Understanding how the faceted catalyst is formed plays a key role in establishing its structure-property correlation and designing a better catalyst,” said Zhenmeng Peng, principal investigator of the catalysis lab at the University of Akron. “The growth process case for the platinum-nickel system is quite sophisticated, so we collaborated with several experienced groups to address the challenges. The cutting-edge techniques at Brookhaven National Lab were of great help to study this research topic.”

Using the ultrabright x-rays at NSLS-II and the advanced capabilities of NSLS-II’s In situ and Operando Soft X-ray Spectroscopy (IOS) beamline, the researchers revealed the chemical characterization of the catalyst’s growth pathway in real time. Their findings are published in Nature Communications.

“We used a research technique called ambient-pressure x-ray photoelectron spectroscopy (AP-XPS) to study the surface composition and chemical state of the metals in the nanoparticles during the growth reaction,” said Iradwikanari Waluyo, lead scientist at IOS and a co-corresponding author of the research paper. “In this technique, we direct x-rays at a sample, which causes electrons to be released. By analyzing the energy of these electrons, we are able to distinguish the chemical elements in the sample, as well as their chemical and oxidation states.”

Hunt, who is also an author on the paper, added, “It is similar to the way sunlight interacts with our clothing. Sunlight is roughly yellow, but once it hits a person’s shirt, you can tell whether the shirt is blue, red, or green.”

Rather than colors, the scientists were identifying chemical information on the surface of the catalyst and comparing it to its interior. They discovered that, during the growth reaction, metallic platinum forms first and becomes the core of the nanoparticles. Then, when the reaction reaches a slightly higher temperature, platinum helps form metallic nickel, which later segregates to the surface of the nanoparticle. In the final stages of growth, the surface becomes roughly an equal mixture of the two metals. This interesting synergistic effect between platinum and nickel plays a significant role in the development of the nanoparticle’s octahedral shape, as well as its reactivity.

“The nice thing about these findings is that nickel is a cheap material, whereas platinum is expensive,” Hunt said. “So, if the nickel on the surface of the nanoparticle is catalyzing the reaction, and these nanoparticles are still more active than platinum by itself, then hopefully, with more research, we can figure out the minimum amount of platinum to add and still get the high activity, creating a more cost-effective catalyst.”

The findings depended on the advanced capabilities of IOS, where the researchers were able to run the experiments at gas pressures higher than what is usually possible in conventional XPS experiments.

“At IOS, we were able to follow changes in the composition and chemical state of the nanoparticles in real time during the real growth conditions,” said Waluyo.

Additional x-ray and electron imaging studies completed at the Advanced Photon Source (APS) at DOE’s Argonne National Laboratory–another DOE Office of Science User Facility–and University of California-Irvine, respectively, complemented the work at NSLS-II.

“This fundamental work highlights the significant role of segregated nickel in forming the octahedral-shaped catalyst. We have achieved more insight into shape control of catalyst nanoparticles,” Peng said. “Our next step is to study catalytic properties of the faceted nanoparticles to understand the structure-property correlation.”

Atomic-scale capillaries block smallest ions thanks to Graphene – Structures are ideal in Desalination and Filtration Technologies


graphene atomicscalec de sal                                       Credit: University of Manchester

 

** See More About Graphene (YouTube Video) and Desalination at the end of this article **

Researchers at The University of Manchester’s National Graphene Institute in the UK have succeeded in making artificial channels just one atom in size for the first time. The new capillaries, which are very much like natural protein channels such as aquaporins, are small enough to block the flow of smallest ions like Na+ and Cl- but allow water to flow through freely. As well as improving our fundamental understanding of molecular transport at the atomic scale, and especially in biological systems, the structures could be ideal in desalination and filtration technologies.

“Obviously, it is impossible to make capillaries smaller than one atom in size,” explains team leader Sir Andre Geim. “Our feat seemed nigh on impossible, even in hindsight, and it was difficult to imagine such tiny capillaries just a couple of years ago.”

Naturally occurring protein channels, such as aquaporins, allow water to quickly permeate through them but block hydrated ions larger than around 7 A in size thanks to mechanisms like steric (size) exclusion and electrostatic repulsion. Researchers have been trying to make artificial capillaries that work just like their natural counterparts, but despite much progress in creating nanoscale pores and nanotubes, all such structures to date have still been much bigger than biological channels.

Geim and colleagues have now fabricated channels that are around just 3.4 A in height. This is about half the size of the smallest hydrated ions, such as K+ and Cl-, which have a diameter of 6.6 A. These channels behave just like protein channels in that they are small enough to block these ions but are sufficiently big to allow water molecules (with a diameter of around 2.8 A) to freely flow through.

The structures could, importantly, help in the development of cost-effective, high-flux filters for water desalination and related technologies – a holy grail for researchers in the field.

Credit: University of Manchester

Atomic-scale Lego

Publishing their findings in Science the researchers made their structures using a van der Waals assembly technique, also known as “atomic-scale Lego”, which was invented thanks to research on graphene. “We cleave atomically flat nanocrystals just 50 and 200 nanometre in thickness from bulk graphite and then place strips of monolayer graphene onto the surface of these nanocrystals,” explains Dr. Radha Boya, a co-author of the research paper. “These strips serve as spacers between the two crystals when a similar atomically-flat crystal is subsequently placed on top. The resulting trilayer assembly can be viewed as a pair of edge dislocations connected with a flat void in between. This space can accommodate only one atomic layer of water.”

Using the  monolayers as spacers is a first and this is what makes the new channels different from any previous structures, she says.

The Manchester scientists designed their 2-D capillaries to be 130 nm wide and several microns in length. They assembled them atop a silicon nitride membrane that separated two isolated containers to ensure that the channels were the only pathway through which water and ions could flow.

Until now, researchers had only been able to measure water flowing though capillaries that had much thicker spacers (around 6.7 A high). And while some of their  indicated that smaller 2-D cavities should collapse because of van der Waals attraction between the opposite walls, other calculations pointed to the fact that  inside the slits could actually act as a support and prevent even one-atom-high slits (just 3.4 A tall) from falling down. This is indeed what the Manchester team has now found in its experiments.

Measuring water and ion flow

“We measured water permeation through our channels using a technique known as gravimetry,” says Radha. “Here, we allow water in a small sealed container to evaporate exclusively through the capillaries and we then accurately measure (to microgram precision) how much weight the container loses over a period of several hours.”

To do this, the researchers say they built a large number of channels (over a hundred) in parallel to increase the sensitivity of their measurements. They also used thicker top crystals to prevent sagging, and clipped the top opening of the capillaries (using plasma etching) to remove any potential blockages by thin edges present here.

To measure ion flow, they forced ions to move through the capillaries by applying an electric field and then measured the resulting currents. “If our capillaries were two atoms high, we found that small ions can move freely though them, just like what happens in bulk water,” says Radha. “In contrast, no ions could pass through our ultimately-small one-atom-high channels.

“The exception was protons, which are known to move through water as true subatomic particles, rather than ions dressed up in relatively large hydration shells several angstroms in diameter. Our channels thus block all hydrated ions but allow protons to pass.”

Since these  behave in the same way as protein channels, they will be important for better understanding how water and ions behave on the molecular scale – as in angstrom-scale biological filters. “Our work (both present and previous) shows that atomically-confined water has very different properties from those of bulk ,” explains Geim. “For example, it becomes strongly layered, has a different structure, and exhibits radically dissimilar dielectric properties.”

 Explore further: Devices made from 2-D materials separate salts in seawater

More information: Dorri Halbertal et al. Imaging resonant dissipation from individual atomic defects in graphene, Science (2017). DOI: 10.1126/science.aan0877 , https://arxiv.org/abs/1811.09227

Want to Read More About Cutting Edge Desalination, Energy Storage and Carbon Nanotubes?

opt-cnts-for-water-wang-mutha-nanotubes_0MIT: Optimizing carbon nanotube electrodes for energy storage and water desalination applications

 

 

 

Graphene for Water Desalination

 

Water, one of the world’s most abundant and highly demanded resources for sustaining life, agriculture, and industry, is being contaminated globally or is unsafe for drinking, creating a need for new and better desalination methods. Current desalination methods have high financial, energy, construction, and operating costs, resulting in them contributing to less than 1% of the world’s reserve water supplies. Advances in nanoscale science and engineering suggest that more cost effective and environmentally friendly desalination process using graphene is possible …

Argonne National Laboratory – A New Membrane Discovery Makes Hydrogen Fuel from Water and Sunlight


hydrogen membrane discoveryada
Two membrane-bound protein complexes that work together with a synthetic catalyst to produce hydrogen from water. Credit: Olivia Johnson and Lisa Utschig

A chemical reaction pathway central to plant biology have been adapted to form the backbone of a new process that converts water into hydrogen fuel using energy from the sun.

argonne nlIn a recent study from the U.S. Department of Energy’s (DOE) Argonne National Laboratory, scientists have combined two -bound protein complexes to perform a complete conversion of water molecules to  and oxygen.

The work builds on an earlier study that examined one of these protein complexes, called Photosystem I, a membrane protein that can use energy from light to feed electrons to an inorganic  that makes hydrogen. This part of the reaction, however, represents only half of the overall process needed for hydrogen generation.

By using a second  that uses energy from light to split water and take electrons from it, called Photosystem II, Argonne chemist Lisa Utschig and her colleagues were able to take electrons from water and feed them to Photosystem I.

“The beauty of this design is in its simplicity—you can self-assemble the catalyst with the natural membrane to do the chemistry you want”—Lisa Utschig, Argonne chemist

In an earlier experiment, the researchers provided Photosystem I with electrons from a sacrificial electron donor. “The trick was how to get two electrons to the catalyst in fast succession,” Utschig said.

The two protein complexes are embedded in , like those found inside the oxygen-creating chloroplasts in higher plants. “The membrane, which we have taken directly from nature, is essential for pairing the two photosystems,” Utschig said. “It structurally supports both of them simultaneously and provides a direct pathway for inter- electron transfer, but doesn’t impede catalyst binding to Photosystem I.”

According to Utschig, the Z-scheme—which is the technical name for the light-triggered electron transport chain of natural photosynthesis that occurs in the thylakoid membrane—and the synthetic catalyst come together quite elegantly. “The beauty of this design is in its simplicity—you can self-assemble the catalyst with the natural membrane to do the chemistry you want,” she said.

One additional improvement involved the substitution of cobalt or nickel-containing catalysts for the expensive platinum catalyst that had been used in the earlier study. The new cobalt or nickel catalysts could dramatically reduce potential costs.

The next step for the research, according to Utschig, involves incorporating the membrane-bound Z-scheme into a living system. “Once we have an in vivo system—one in which the process is happening in a living organism—we will really be able to see the rubber hitting the road in terms of hydrogen production,” she said.

 Explore further: New research sheds light on photosynthesis and creation of solar fuel

More information: Lisa M. Utschig et al, Z-scheme solar water splitting via self-assembly of photosystem I-catalyst hybrids in thylakoid membranes, Chemical Science (2018). DOI: 10.1039/c8sc02841a

 

Saving Us From AI’s Worst Case Scenarios – An Interview with MIT Professor Max Tegmark


artificial-intelligence-people-mit-00_2

(AI) “… Instead, the largest threat would be if it turns extremely competent. This is because the competent goals may not be aligned with our goals either because it is controlled by someone who does not share our goals, or because the machine itself has power over us.”

Artificial intelligence (AI) is one of the hottest trends pursued by the private sector, academics, and government institutions. The promise of AI is to make our lives better: to have an electronic brain to complement our own, to take over menial tasks so that we can focus on higher value activities, to allow us to make better decisions in our personal and professional lives.

There is also a darker side to AI that many fear. What happens when bad actors leverage AI for bad uses? How will we ensure that AI is not a wedge to divide the haves and have-nots further apart? Moreover, what happens when our jobs are fundamentally changed or go away when we derive so much of what defines us from what we do professionally?

Max Tegmark has studied these issues intimately from his perch as a professor at MIT and as the  co-founder of the Future of Life Institute. He has synthesized his own thoughts into a powerful book called Life 3.0: Being Human in the Age of Artificial Intelligence. As the title suggests, AI will redefine what it means to be human due to the scale of the changes it will bring about.

                                                                     

Tegmark likes the analogy of the automobile to make the case for what is necessary for AI to be beneficial for humanity. He notes that the three things that are necessary are that it have an engine (the power to create value), it needs steering (so that it can be moved toward good rather than evil ends), and it must have direction or a roadmap for how to get to the beneficial destination. He notes that “the way    to create a good future with technology is to continuously win the wisdom race. As technology grows more powerful, the wisdom in which we manage it must keep up.” He describes all of this and more in this interview.  professor mark tegmark https___blogs-images.forbes.com_peterhigh_files_2019_01_maxresdefault-300x169

MIT Professor and Author, Max Tegmark CREDIT: MIT 

(To listen to an unabridged podcast version of this interview, please click this link. This is the 31st interview in the Tech Influencers series. To listen to past interviews with the likes of former Mexican President Vicente Fox, Sal Khan, Sebastian Thrun, Steve Case, Craig Newmark, Stewart Butterfield, and Meg Whitman, please visit this link. To read future articles in this series, please follow me on on Twitter @PeterAHigh.)

The Interview by Peter High

Peter High is President of Metis Strategy, a business and IT advisory firm. His latest book is Implementing World Class IT Strategy. He is also the author of World Class IT: Why Businesses Succeed When IT Triumphs.

 

Peter High: Congratulations on your book, Life 3.0: Being Human in the Age of Artificial Intelligence. When and where did your interest in the topic of Artificial Intelligence [AI] begin?

High: When you have described your efforts to figure out where AI might take us, you make an analogy to driving a car. First, you need the engine and the power to make AI work. Second, you need steering because AI must be steered in one direction or another. Lastly, there needs to be a destination. Can you elaborate on each of those topics, and could you give us your hypothesis as to where we are heading?

Tegmark: If you are building a rocket or a car, it would be nuts to exclusively focus on the engine’s power while ignoring how to steer it. Even if you have the steering sorted out, you are going to have trouble if you are unable to determine where you are trying to go with it. Unfortunately, I believe this is what we are doing as we continue to build more powerful technology, especially with AI. To be as ambitious as possible, we need to think about all three elements, which are the power, the steering, and the destination of the technology.

Because it is so important, I spend a great deal of time at MIT focused on steering. Along with Jaan Tallinn and several other colleagues, I co-founded the Future of Life Institute, which [focuses on] the destination. While we are making AI more powerful, it is critical to know what type of society we are aspiring to create with this technology. If society accomplishes the original goal of AI research, which is to make so-called “Artificial General Intelligence” [AGI] that can do all jobs better than humans, we have to determine what it will mean to be a human in the future. I am convinced that if we succeed, it will either be the best or the worst advancement ever, and it will come down to the amount of planning we do now. If we have no clue about where we want to go, it is unlikely that we are going to end up in an ideal situation. However, if we plan accordingly and steer technology in the right direction, we can create an inspiring future that will allow humanity to flourish in a way that we have never seen before.

I believe this to be true because the reason that today’s society is better than the Stone Age is because of technology. Everything I love about civilization is the product of intelligence. Technology is the reason why the life expectancy is no longer 32 years. If we can take this further and amplify our intelligence with AI, we have the potential to solve humanity’s greatest challenges. These technologies can help us cure other diseases that we are currently told are incurable because we have not been smart enough to solve them. Further, technology can lift everybody out of poverty, solve the issues in our climate, and allow us to go in inspiring directions that we have not even thought of yet. It is clear that there is an enormous upside if we get this right, and that is why I am incredibly motivated to work on that.

High: I am struck by the caveman analogy. We are so far removed from cavemen and cavewomen that a modern human and caveman would not be able to recognize each other in terms of life expectancy, the ability to communicate, and the time we have to reflect and ponder our situation, among other differences.

Tegmark: That is so true, and you said something super interesting there. While we are so far removed, we are largely stuck in the caveman mindset. When we were cavemen, the most powerful technology we had were rocks and sticks, which limited our ancestors’ ability to cause significant damage. While there were always cavemen that wanted to harm as many people as possible, there was only so much damage one could do with a rock and a stick.

Unfortunately, with nuclear weapons, the damage can be devastating, and as technology gets more powerful, it becomes easier to mess up. However, at the same time, we now have more power to use technology for good. Because of both of these factors, the more powerful the technology gets, the more important the steering becomes. Technology is neither good nor evil, so when people ask me if I am for AI or against AI, I ask them if they are for fire or against fire. Fire can obviously be used to keep your house warm in the winter, or it can be used for arson. To keep this under control, we have put a great deal of effort into the steering of fire. We have fire extinguishers and fire departments, and we created ways to punish people who use fire in ways that are not appropriate.

We have to step out of our caveman mindset. The way to create a good future with technology is to continuously win the wisdom race. As technology grows more powerful, the wisdom in which we manage it must keep up. This was true with fire and with the automobile engine, and I believe we were successful in those missions. While we continuously messed up, we learned from our mistakes and invented the seat belt, the airbag, traffic lights, and laws against speeding. Ever since we were cavemen, we have been able to stay ahead in the wisdom race by learning from our mistakes. However, as technology gets more powerful, the margin for error is evaporating, and one mistake in the future may be one too many. We obviously do not want to have an “accidental” nuclear war with Russia and just brush it off as a mistake that we can learn from and be more careful of the next time. It is far more effective to be proactive and plan ahead, rather than reactive. I believe we need to implement this mindset before we build technology that can do everything better than us.

High: You mentioned there are some attributes that we still share with our distant ancestors. Even if AGI does not come for decades, the change will be almost the same in magnitude as the change from cavemen to the present day. For example, it potentially has the power to change the way in which we work. You have written persuasively about the possibility of what we do being taken over by AI. In a society where many of us are defined by the work that we do, it is quite unsettling to know that, what I love about my day job today will be done better by AI. We may need to redefine ourselves as a result. What are your perspectives on that?

Tegmark: I agree with that, and I would take it a step further and say that the jump from today to AGI is a bigger one than the jump from cavemen to the present day. When we were cavemen, we were the smartest species on the planet, and we still are today. With AGI, we will not be, which is a huge game changer. While we have doubled our life expectancy and seen new technologies emerge, we are still stuck on this tiny planet, and the majority of people still die within a century. However, if we can build AGI, the opportunities will be limitless.

People are not realizing this, and because we are still stuck in this caveman mindset, we continue to think that it will take us thousands of years to find a way to live 200, or even 1,000 years. Moreover, the mindset that we have to invent all the technologies ourselves has led us to believe that it will take thousands of years to move to another solar system. However, this is far from true because, by definition, AGI has the ability to do all jobs better than us, including jobs that can invent better AI among other technologies. This capability has led many to believe that AGI could be the last invention that we need to make. We may end up with a future where life on Earth and beyond flourishes for billions of years, not just for the next election cycle. This could all start on Earth if we can solve intelligence and use it to go in amazing directions. If we get this right, the upside will be far more significant than the benefits we reaped going from cavemen to the present day.

Regarding what it means to be a human if all jobs can be done better by machines, that is why the subtitle of my book is, Being Human in the Age of Artificial Intelligence. Jobs do not just give us an income, they give us meaning and a sense of purpose in our lives. Even if we can produce all that we need with machines and figure out how to share the wealth, it does not solve the question of how that purpose and meaning will be replaced. This crucial dilemma absolutely cannot be left to tech nerds such as myself because AI programmers are not world experts on what makes humans happy. We need to broaden this conversation to get everyone on board and discuss what type of future we want to create. This is essential, and unfortunately, I do not believe that we are going about this the right way.

Students often walk into my office asking for career advice, and in response, I always start by asking them about where they want to be in the future. If all the student can say is that they may get cancer, be murdered, or run over by a truck, that is a terrible strategy for career planning. I want these people to come in with fire in their eyes and say, “This is where I want to be.” From there, we can figure out what the challenges are and come up with a strong strategy to avoid them so that they can get to where they want to be. While we should take this same approach as a species, it is not the one we are taking. Every time I go to the movies and see something about the future, it showcases one dystopia after another. This approach makes us paranoid, and it divides us in the same way that fear always has. It is crucial for us to have a conversation around the type of futures we are excited about. I am not talking about getting 10 percent richer or curing a minor disease, but I want people to think big. If machines can do everything with technology, what kind of future would fire us up? What type of society do we want to live in? What would your typical day look like? If we can articulate a shared, positive vision that catches on around the world, I believe we have a real chance of getting there.

High: What happens if AGI gets to the point where the work that you are doing at MIT and at the Future of Life Institute is no longer meaningful?

Tegmark: That is a hard-hitting question. I get an incredible amount of joy from figuring stuff out, and if I could just press a button and the computer would write my papers for me, would it be as much fun? This is not an easy topic.

In my book, I discuss twelve different futures that people can choose between. Just because we can think about a future that we are convinced is perfect, does not mean that we should do nothing. At a minimum, we should do the necessary thinking that will allow us to steer our future in the right direction. There are some obvious decisions that need to be made now, such as how income inequality will be handled. While we may be able to dramatically grow the overall world GDP, we must be able to share this economic pie so that everybody is better off. As more and more jobs get replaced by machines, incomes that have typically been paid in salaries will go towards whoever owns the machines. This concept is why Facebook, a high-tech company, is twelve times more valuable than Ford, despite the fact that it has eight times fewer employees. Unfortunately, we have not begun to make these decisions, and if we are unable to do so to the point where everyone benefits, then shame on us. As companies become more high-tech, we must make twists to the system to avoid leaving more people behind and ending up with far more income inequality. If this problem does not get solved, we will end up with more and more angry people, which will make democracy more and more unworkable. However, on the bright side, all that wealth makes this problem relatively easy to fix. All that needs to be done is to bring in enough tax revenue so that everyone can be better off.

The second aspect, which I believe is a no-brainer, is that we must ensure that we avoid a damaging arms race with the lethal autonomous weapons. Fortunately, nearly all the research in AI is going towards helping people in various ways, and most AI researchers want to keep it that way. Around the time I was born, we were on the cusp of a horrible arms race with bioweapons. When this happened, the biologists pushed hard to get an international ban on bioweapons, and as a result, most people cannot remember the last time they read about a bioweapon terrorist attack in the newspaper. If you ask a hundred random people on the street about their opinions on biology, they are all going to smile and associate it with new cures, rather than with bioweapons. It is critical that we handle AI weapons in a similar way.

We need to put a greater focus on the steering aspect of AI. Nearly all of the funding going into AI has been around making it more powerful, and little is going towards AI safety research. Even increasing this a little bit will make an impactful difference. As we put AI in charge of more infrastructure-level decisions, we must transform buggy and hackable computers into robust AI systems that can be trusted. If we fail to do so, all these fascinating new technologies can malfunction, harm us, or be hacked and used against us.ai-davenport-artificial-intelligence-pilots-innovators-early-adopters-implementation-industry-production-1200

As AI becomes more and more capable, we have to work on the value alignment problems of AI. The real threat with AGI is not that it is going to turn evil in the way that it does in the silly Hollywood movies. Instead, the largest threat would be if it turns extremely competent. This is because the competent goals may not be aligned with our goals either because it is controlled by someone who does not share our goals, or because the machine itself has power over us. We must solve some tough technical challenges in order to neutralize this threat. We have to figure out how to make machines understand our goals, adopt our goals, and then keep these goals if they get smarter. Although work has begun in this area, these problems are hard, and it may take roughly 30 years to solve them. It is absolutely critical that we focus on this problem now so that we have the answers by the time we need them. We have to stop looking at these issues as an afterthought.

High: What role do private sector, academic, and governmental institutions play? Each is exerting influence in their own ways, and they are progressing at different rates. How do you see that balance?

mit tegmark bkawytw4szvjjak4s5xa8e-320-80Tegmark: Academia is great for developing solutions to AI safety problems while making them publicly available so that everyone in the world can use them. You want safety solutions to be free because if someone owns the IP on them, it will cause a worse outcome.

I believe private companies have mostly played a constructive role in helping encourage the safety work around AI. For example, most of the big players in AI, such as Google, IBM, Microsoft, Facebook, and many international companies, have joined together in an AI partnership to encourage safety development.

On the flip side, governments need to step it up and provide more funding for the safety research. No government should fund nuclear reactor research without funding reactor safety research. Similarly, no country should fund computer science research without putting a decent slice towards the steering part.

That is my wish list as to what we should focus on in the current day to maximize the chances of this going well. In parallel, everyone else needs to ask themselves what future they want to see. They should remember that the next time they vote and whenever they exert influence, we want to create a future for everybody.

High: How do you keep up with the progress or lack thereof of these advances?

Tegmark: Both through the research taking place at MIT and through the nerdy AI conferences that I go to. Additionally, the non-profit work that I have been doing has been fascinating. I have spent a great deal of time speaking with top researchers and CEOs who are making incredible progress on this. I am encouraged, and I find that the leaders are mostly an idealistic bunch. I do not believe that they are doing this exclusively for the money. Instead, they want this technology to represent an opportunity to create a better future. We need to make sure that the society at large shares this goal of channeling AI for good, instead of using it to hack elections and create new ways to murder people anonymously. That would be an incredibly sad result of all these good intentions.

Peter High is President of Metis Strategy, a business and IT advisory firm. His latest book is Implementing World Class IT Strategy. He is also the author of World Class IT: Why Businesses Succeed When IT Triumphs. Peter moderates the Forum on World Class IT podcast series. He speaks at conferences around the world. Follow him on Twitter @PeterAHigh.

 

I am the president of Metis Strategy, a business and IT strategy firm that I founded in 2001. I have advised many of the best chief information officers at multi-billion dollar corporations in the United States and abroad. I’ve written for the Wall Street Journal, CIO Magazi… MORE

Los Alamos National Laboratory – Stable light from ‘squashed’ Quantum Dots provide viable alternative to presently employed nanoscale light sources used in the Commercialization of quantum-dot displays, TV’s and more …


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Novel colloidal quantum dots are formed of an emitting cadmium/selenium (Cd/Se) core enclosed into a compositionally graded CdxZn1-xSe shell wherein the fraction of zinc versus cadmium increases towards the dot’s periphery. Due to a …more

 

” The new colloidal processing techniques allow for preparation of virtually ideal quantum-dot emitters with nearly 100 percent emission quantum yields shown for a wide range of visible, infrared and ultraviolet wavelengths. These advances have been exploited in a variety of light-emission technologies, resulting in successful commercialization of quantum-dot displays and TV sets … “

Intentionally “squashing” colloidal quantum dots during chemical synthesis creates dots capable of stable, “blink-free” light emission that is fully comparable with the light produced by dots made with more complex processes. The squashed dots emit spectrally narrow light with a highly stable intensity and a non-fluctuating emission energy. New research at Los Alamos National Laboratory suggests that the strained colloidal quantum dots represent a viable alternative to presently employed nanoscale light sources, and they deserve exploration as single-particle, nanoscale light sources for optical “quantum” circuits, ultrasensitive sensors, and medical diagnostics.

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“In addition to exhibiting greatly improved performance over traditional produced , these new strained dots could offer unprecedented flexibility in manipulating their emission color, in combination with the unusually narrow, ‘subthermal’ linewidth,” said Victor Klimov, lead Los Alamos researcher on the project. “The squashed dots also show compatibility with virtually any substrate or embedding medium as well as various chemical and biological environments.”

The new colloidal processing techniques allow for preparation of virtually ideal quantum-dot emitters with nearly 100 percent emission quantum yields shown for a wide range of visible, infrared and ultraviolet wavelengths. These advances have been exploited in a variety of light-emission technologies, resulting in successful commercialization of quantum-dot displays and TV sets.

The next frontier is exploration of  as single-particle, nanoscale light sources. Such future “single-dot” technologies would require particles with highly stable, nonfluctuating spectral characteristics. Recently, there has been considerable progress in eliminating random variations in emission intensity by protecting a small emitting core with an especially thick outer layer. However, these thick-shell structures still exhibit strong fluctuations in emission spectra.

los alamos xlosalamoslogo.png.pagespeed.ic.w4zn0ixzm6In a new publication in the journal Nature Materials, Los Alamos researchers demonstrated that spectral fluctuations in single-dot emission can be nearly completely suppressed by applying a new method of “strain engineering.” The key in this approach is to combine in a core/shell motif two semiconductors with directionally asymmetric lattice mismatch, which results in anisotropic compression of the emitting core.

This modifies the structures of electronic states of a  dot and thereby its  emitting properties. One implication of these changes is the realization of the regime of local charge neutrality of the emitting “exciton” state, which greatly reduces its coupling to lattice vibrations and fluctuating electrostatic environment, key to suppressing fluctuations in the emitted spectrum. An additional benefit of the modified electronic structures is dramatic narrowing of the  linewidth, which becomes smaller than the room-temperature thermal energy.

 Explore further: Sandwich structure of nanocrystals as quantum light source

More information: Young-Shin Park et al, Asymmetrically strained quantum dots with non-fluctuating single-dot emission spectra and subthermal room-temperature linewidths, Nature Materials (2018). DOI: 10.1038/s41563-018-0254-7