Why Our Crazy-Smart AI Still Sucks at Transcribing Speech

Wired News - Fri, 08/04/2016 - 9:45am
The task of providing accurate transcriptions of long blocks of actual human conversation remains beyond the abilities of today's most advanced software. The post Why Our Crazy-Smart AI Still Sucks at Transcribing Speech appeared first on WIRED.

Categories: Science

First transistors made entirely of nanocrystal ‘inks’ in simplified process

Kurzweil AI - Fri, 08/04/2016 - 9:41am

Because this process works at relatively low temperatures, many transistors can be made on a flexible backing at once. (credit: University of Pennsylvania)

University of Pennsylvania engineers have developed a simplified new approach for making transistors by sequentially depositing their components in the form of liquid nanocrystal “inks.” The new process open the door for transistors and other electronic components to be built into flexible or wearable applications. It also avoids the highly complex current process for creating transistors, which requires high-temperature, high-vacuum equipment. Also, the new lower-temperature process is compatible with a wide array of materials and can be applied to larger areas.

Transistors patterned on plastic backing

The researchers’ nanocrystal-based field effect transistors were patterned onto flexible plastic backings using spin coating, but could eventually be constructed by additive manufacturing systems, like 3D printers.

Published in the journal Science,  the study was lead by Cherie Kagan, the Stephen J. Angello Professor in the School of Engineering and Applied Science, and Ji-Hyuk Choi, then a member of her lab, now a senior researcher at the Korea Institute of Geoscience and Mineral Resources. Researchers at Korea University Korea’s Yonsei University were also involved.

Kagan’s group developed four nanocrystal inks that comprise the transistor, then deposited them on a flexible backing. (credit: University of Pennsylvania)

The researchers began by dispersing a specific type of nanocrystals in a liquid, creating nanocrystal inks. They developed a library of four of these inks: a conductor (silver), an insulator (aluminum oxide), a semiconductor (cadmium selenide), and a conductor combined with a dopant (a mixture of silver and indium). (“Doping” the semiconductor layer of a transistor with impurities controls whether the device creates a positive or negative charge.)

“These materials are colloids just like the ink in your inkjet printer,” Kagan said, “but you can get all the characteristics that you want and expect from the analogous bulk materials, such as whether they’re conductors, semiconductors or insulators.” Although the electrical properties of several of these nanocrystal inks had been independently verified, they had never been combined into full devices. “Our question was whether you could lay them down on a surface in such a way that they work together to form functional transistors.”

Laying down patterns in layers

Such a process entails layering or mixing them in precise patterns.

First, the conductive silver nanocrystal ink was deposited from liquid on a flexible plastic surface that was treated with a photolithographic mask, then rapidly spun to draw it out in an even layer. The mask was then removed to leave the silver ink in the shape of the transistor’s gate electrode.

The researchers followed that layer by spin-coating a layer of the aluminum oxide nanocrystal-based insulator, then a layer of the cadmium selenide nanocrystal-based semiconductor and finally another masked layer for the indium/silver mixture, which forms the transistor’s source and drain electrodes. Upon heating at relatively low temperatures, the indium dopant diffused from those electrodes into the semiconductor component.

“The trick with working with solution-based materials is making sure that, when you add the second layer, it doesn’t wash off the first, and so on,” Kagan said. “We had to treat the surfaces of the nanocrystals, both when they’re first in solution and after they’re deposited, to make sure they have the right electrical properties and that they stick together in the configuration we want.”

Because this entirely ink-based fabrication process works at lower temperatures than existing vacuum-based methods, the researchers were able to make several transistors on the same flexible plastic backing at the same time.

The inks’ specialized surface chemistry allowed them to stay in configuration without losing their electrical properties. (credit: University of Pennsylvania)

“Making transistors over larger areas and at lower temperatures have been goals for an emerging class of technologies, when people think of the Internet of things, large area flexible electronics and wearable devices,” Kagan said. “We haven’t developed all of the necessary aspects so they could be printed yet, but because these materials are all solution-based, it demonstrates the promise of this materials class and sets the stage for additive manufacturing.”

Because this entirely ink-based fabrication process works at lower temperatures than existing vacuum-based methods, the researchers were able to make several transistors on the same flexible plastic backing at the same time.

3D-printing transistors for wearables

“This is the first work,” Choi said, “showing that all the components, the metallic, insulating, and semiconducting layers of the transistors, and even the doping of the semiconductor, could be made from nanocrystals.”

“Making transistors over larger areas and at lower temperatures have been goals for an emerging class of technologies, when people think of the Internet of things, large area flexible electronics and wearable devices,” Kagan said. “We haven’t developed all of the necessary aspects so they could be printed yet, but because these materials are all solution-based, it demonstrates the promise of this materials class and sets the stage for additive manufacturing.”

The research was supported by the National Science Foundation, the U.S. Department of Energy, the Office of Naval Research, and the Korea Institute of Geoscience and Mineral Resources funded by the Ministry of Science, ICT, and Future Planning of Korea.

Abstract of Exploiting the colloidal nanocrystal library to construct electronic devices

Synthetic methods produce libraries of colloidal nanocrystals with tunable physical properties by tailoring the nanocrystal size, shape, and composition. Here, we exploit colloidal nanocrystal diversity and design the materials, interfaces, and processes to construct all-nanocrystal electronic devices using solution-based processes. Metallic silver and semiconducting cadmium selenide nanocrystals are deposited to form high-conductivity and high-mobility thin-film electrodes and channel layers of field-effect transistors. Insulating aluminum oxide nanocrystals are assembled layer by layer with polyelectrolytes to form high–dielectric constant gate insulator layers for low-voltage device operation. Metallic indium nanocrystals are codispersed with silver nanocrystals to integrate an indium supply in the deposited electrodes that serves to passivate and dope the cadmium selenide nanocrystal channel layer. We fabricate all-nanocrystal field-effect transistors on flexible plastics with electron mobilities of 21.7 square centimeters per volt-second.

Categories: Science

SpaceX Launches CRS-8 Space Station Re-Supply Mission | Video

Space.com - Fri, 08/04/2016 - 9:23am
A Falcon 9 rocket lauched the Dragon spacecraft carrying 7,000 lbs. (3175 kg) of supplies, vehicle hardware and science experiments. In a spaceflight first, the first stage of the rocket successfully landed on an ocean barge in the Atlantic Ocea
Categories: Science

SpaceX Sticks a Rocket Landing at Sea in Historic First

Space.com - Fri, 08/04/2016 - 9:10am
Fifth time's the charm! SpaceX successfully landed a Falcon 9 reusable rocket booster on a drone ship — a first for the company — following a launch from Cape Canaveral today (April 8).
Categories: Science

SpaceX Nails Ocean Barge Landing On 5th Try | Video

Space.com - Fri, 08/04/2016 - 9:05am
After launching the latest Space Station re-supply mission on April 8th, 2016, the first stage of the Falcon 9 rocket landed successfully on SpaceX's "Of Course I Still Love You" drone ship in the Atlantic Ocean.
Categories: Science

Best textile manufacturing methods for creating human tissues with stem cells

Kurzweil AI - Fri, 08/04/2016 - 8:32am

All four textile manufacturing processes and corresponding scaffold (structure) types studied exhibited the presence of lipid vacuoles (small red spheres, right column, indicating stem cells undergoing random differentiation), compared to control (left). Electrospun scaffolds (row a) exhibited only a monolayer of lipid vacuoles in a single focal plane, while meltblown, spunbond, and carded scaffolds (rows b, c, d) exhibited vacuoles in multiple planes throughout the fabric thickness. Scale bars: 100 μm (credit: S. A. Tuin et al./Biomedical Materials)

Elizabeth Loboa, dean of the Missouri University College of Engineering, and her team have tested new tissue- engineering methods (based on textile manufacturing) to find ones that are most cost-effective and can be produced in larger quantities.

Tissue engineering is a process that uses novel biomaterials seeded with stem cells to grow and replace missing tissues. When certain types of materials are used, the “scaffolds” that are created to hold stem cells eventually degrade, leaving natural tissue in its place. The new tissues could help patients suffering from wounds caused by diabetes and circulation disorders, patients in need of cartilage or bone repair, and women who have had mastectomies by replacing their breast tissue. The challenge is creating enough of the material on a scale that clinicians need to treat patients.

Comparing textile manufacturing techniques

Electrospinning experiment: nanofibers are collected into an ethanol bath and removed at predefined time intervals (credit: J. M. Coburn et al./The Johns Hopkins University/PNAS)

In typical tissue engineering approaches that use fibers as scaffolds, non-woven materials are often bonded together using an electrostatic field. This process, called electrospinning (see Nanoscale scaffolds and stem cells show promise in cartilage repair and Improved artificial blood vessels), creates the scaffolds needed to attach to stem cells.

However, large-scale production with electrospinning is not cost-effective. “Electrospinning produces weak fibers, scaffolds that are not consistent, and pores that are too small,” Loboa said. “The goal of ‘scaling up’ is to produce hundreds of meters of material that look the same, have the same properties, and can be used in clinical settings. So we investigated the processes that create textiles, such as clothing and window furnishings like drapery, to scale up the manufacturing process.”

The group published two papers using three industry-standard, high-throughput manufacturing techniques — meltblowing, spunbonding, and carding — to determine if they would create the materials needed to mimic native tissue.

Meltblowing is a technique during which nonwoven materials are created using a molten polymer to create continuous fibers. Spunbond materials are made much the same way but the fibers are drawn into a web while in a solid state instead of a molten one. Carding involves the separation of fibers through the use of rollers, forming the web needed to hold stem cells in place.

Schematic of gilled fiber multifilament spinning and carded scaffold fabrication (credit: Stephen A. Tuin et al./Acta Biomaterialia)

Cost-effective methods

Loboa and her colleagues tested these techniques to create polylactic acid (PLA) scaffolds (a Food and Drug Administration-approved material used as collagen fillers), seeded with human stem cells. They then spent three weeks studying whether the stem cells remained healthy and if they began to differentiate into fat and bone pathways, which is the goal of using stem cells in a clinical setting when new bone and/or new fat tissue is needed at a defect site. Results showed that the three textile manufacturing methods proved as viable if not more so than electrospinning.

“These alternative methods are more cost-effective than electrospinning,” Loboa said. “A small sample of electrospun material could cost between $2 to $5. The cost for the three manufacturing methods is between $.30 to $3.00; these methods proved to be effective and efficient. Next steps include testing how the different scaffolds created in the three methods perform once implanted in animals.”

Researchers at North Carolina State University and the University of North Carolina at Chapel Hill were also involved in the two studies, which were published in Biomedical Materials (open access) and Acta Biomaterialia. The National Science Foundation, the National Institutes of Health, and the Nonwovens Institute provided funding for the studies.

Abstract of Creating tissues from textiles: scalable nonwoven manufacturing techniques for fabrication of tissue engineering scaffolds

Electrospun nonwovens have been used extensively for tissue engineering applications due to their inherent similarities with respect to fibre size and morphology to that of native extracellular matrix (ECM). However, fabrication of large scaffold constructs is time consuming, may require harsh organic solvents, and often results in mechanical properties inferior to the tissue being treated. In order to translate nonwoven based tissue engineering scaffold strategies to clinical use, a high throughput, repeatable, scalable, and economic manufacturing process is needed. We suggest that nonwoven industry standard high throughput manufacturing techniques (meltblowing, spunbond, and carding) can meet this need. In this study, meltblown, spunbond and carded poly(lactic acid) (PLA) nonwovens were evaluated as tissue engineering scaffolds using human adipose derived stem cells (hASC) and compared to electrospun nonwovens. Scaffolds were seeded with hASC and viability, proliferation, and differentiation were evaluated over the course of 3 weeks. We found that nonwovens manufactured via these industry standard, commercially relevant manufacturing techniques were capable of supporting hASC attachment, proliferation, and both adipogenic and osteogenic differentiation of hASC, making them promising candidates for commercialization and translation of nonwoven scaffold based tissue engineering strategies.

Abstract of Fabrication of novel high surface area mushroom gilled fibers and their effects on human adipose derived stem cells under pulsatile fluid flow for tissue engineering applications

The fabrication and characterization of novel high surface area hollow gilled fiber tissue engineering scaffolds via industrially relevant, scalable, repeatable, high speed, and economical nonwoven carding technology is described. Scaffolds were validated as tissue engineering scaffolds using human adipose derived stem cells (hASC) exposed to pulsatile fluid flow (PFF). The effects of fiber morphology on the proliferation and viability of hASC, as well as effects of varied magnitudes of shear stress applied via PFF on the expression of the early osteogenic gene marker runt related transcription factor 2 (RUNX2) were evaluated. Gilled fiber scaffolds led to a significant increase in proliferation of hASC after seven days in static culture, and exhibited fewer dead cells compared to pure PLA round fiber controls. Further, hASC-seeded scaffolds exposed to 3 and 6 dyn/cm2 resulted in significantly increased mRNA expression of RUNX2 after one hour of PFF in the absence of soluble osteogenic induction factors. This is the first study to describe a method for the fabrication of high surface area gilled fibers and scaffolds. The scalable manufacturing process and potential fabrication across multiple nonwoven and woven platforms makes them promising candidates for a variety of applications that require high surface area fibrous materials.

Statement of Significance

We report here for the first time the successful fabrication of novel high surface area gilled fiber scaffolds for tissue engineering applications. Gilled fibers led to a significant increase in proliferation of human adipose derived stem cells after one week in culture, and a greater number of viable cells compared to round fiber controls. Further, in the absence of osteogenic induction factors, gilled fibers led to significantly increased mRNA expression of an early marker for osteogenesis after exposure to pulsatile fluid flow. This is the first study to describe gilled fiber fabrication and their potential for tissue engineering applications. The repeatable, industrially scalable, and versatile fabrication process makes them promising candidates for a variety of scaffold-based tissue engineering applications.

Categories: Science

Moon Will Hit the 'Bull's-Eye' in Stellar Eclipse Sunday

Space.com - Fri, 08/04/2016 - 8:00am
A stellar eclipse will be visible from nearly everywhere in the United States and much of southern Canada on April 10. The crescent moon will "run over" the star Aldebaran in the constellation Taurus.
Categories: Science

Space-Bound Veggies Will Also Sprout in White House Garden

Space.com - Fri, 08/04/2016 - 7:11am
A new crop of green-vegetable seeds headed to the International Space Station today (April 8) as part of an experiment to grow produce in space will also take root in Michelle Obama's White House kitchen garden.
Categories: Science

Jeff Bezos: AWS Will Break $10 Billion This Year

Slashdot - Fri, 08/04/2016 - 7:01am
v3rgEz writes: Jeff Bezos is bullish on the cloud, pegging AWS' sales for this year at $10 billion in a recent letter to shareholders. But he said there was a surprising source of that success: The company's willingness to fail. That said, with AWS now spanning 70 different services, Amazon can afford to fail some as long as few, like EC2 and S3, keep winning. Bezos wrote: "One area where I think we are especially distinctive is failure. I believe we are the best place in the world to fail (we have plenty of practice!), and failure and invention are inseparable twins. To invent you have to experiment, and if you know in advance that it's going to work, it's not an experiment. Most large organizations embrace the idea of invention, but are not willing to suffer the string of failed experiments necessary to get there."

Read more of this story at Slashdot.

Categories: Science

No, Planet Nine Won't Kill Us All

Space.com - Fri, 08/04/2016 - 6:57am
Yesterday (April 7), the New York Post published a video claiming that Planet Nine — a hypothesized world in the solar system's far outer reaches — could send asteroids and comets hurtling into Earth soon. Don't believe it.
Categories: Science

Fallout 4 Wins Best Game At Bafta Awards

Slashdot - Fri, 08/04/2016 - 3:49am
An anonymous reader quotes a report from BBC: Fallout 4 has won the best game of the year at 2016's British Academy Games Awards. It marks the first time its US-based developer Bethesda has won the prize. It did not win in any other category. Fallout 4 is an action-focused role-playing game set in Boston following a nuclear war. It contains hundreds of hours of storyline to explore. Like last year's winner -- Destiny -- it had not won a prize in any of the other categories before taking the top award. The studio's European managing director said he had not expected the result, and recalled that although Fallout is now one of gaming's biggest franchises, it too started out small. "You don't have to have the multi-million dollar budgets to make great games -- I've seen a huge amount of evidence for that tonight," said Sean Brennan.

Read more of this story at Slashdot.

Categories: Science

Astrophysicists find triple star system with 'hot Jupiter'

Science Daily - Fri, 08/04/2016 - 2:17am
Crisp, clear images of a "hot Jupiter" system captured by a physicist were vital in determining that a newly found planet inhabits a three-star system, a phenomenon documented only a few times before.
Categories: Science

Physicists build ultra-powerful accelerator magnet

Science Daily - Fri, 08/04/2016 - 2:17am
The next generation of cutting-edge accelerator magnets is no longer just an idea. Recent tests revealed that the United States and CERN have successfully co-created a prototype superconducting accelerator magnet that is much more powerful than those currently inside the Large Hadron Collider.
Categories: Science

Common prostate cancer treatments suppress immune response, may promote relapse

Science Daily - Fri, 08/04/2016 - 2:17am
Prostate cancer patients and their doctors may want to think twice about the best timing for chemotherapy or radiation therapy in conjunction with a common nonsurgical treatment, based on international research findings.
Categories: Science

HPV vaccine may be effective in adolescents with kidney disease, but less so in those with a kidney transplant

Science Daily - Fri, 08/04/2016 - 2:17am
Following vaccination against human papillomavirus, girls and young women with chronic kidney disease and those on dialysis had antibody levels above the threshold that indicates protection from infection. A significant proportion of patients with kidney transplants showed evidence of an inadequate antibody response to the vaccine.
Categories: Science

Kidneys have an innate clock that affects many metabolic processes in the body

Science Daily - Fri, 08/04/2016 - 2:17am
Daily fluctuations caused by the kidney’s circadian clock have an important effect on the levels of various amino acids, lipids, and other components of blood in the body, say researchers. In individuals who take medications, the kidney’s circadian clock controls drug elimination from the body and therefore can influence the duration of a drug’s action and the effectiveness of the therapy.
Categories: Science

Neutron 'splashes' reveal signature of exotic particles

Science Daily - Fri, 08/04/2016 - 2:15am
Researchers used neutrons to uncover novel behavior in materials that holds promise for quantum computing. The findings provide evidence for long-sought phenomena in a two-dimensional magnet.
Categories: Science

Traditional skin tests used to predict allergies to antibiotics are useless, say researchers

Science Daily - Fri, 08/04/2016 - 2:14am
Skin tests traditionally used to predict allergies to amoxicillin, one of the most commonly prescribed antibiotics in children, are ineffective according to a new study. The findings determined that oral provocation or challenge test, with appropriate follow up, was a more efficient and safer screening method for diagnosing non-life threatening reactions to amoxicillin in children.
Categories: Science

Wisdom is a matter of both heart and mind, research finds

Science Daily - Fri, 08/04/2016 - 2:14am
The fluctuations of your heartbeat may affect your wisdom, according to new research. The study suggests that heart rate variation and thinking process work together to enable wise reasoning about complex social issues.
Categories: Science

'Climate-smart soils' may help balance the carbon budget

Science Daily - Fri, 08/04/2016 - 2:14am
While farm soil grows the world's food and fiber, scientists are examining ways to use it to sequester carbon and mitigate greenhouse gas emissions. But here's the scientific dirt: Soil can help reduce global warming.
Categories: Science