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Claudia Mihaela Dung
Lives in Bucharest, Romania
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Claudia Mihaela Dung

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Eli Goldratt wrote a fictional novel – The Goal: A Process of Ongoing Improvement – back in 1984 and caused a revolution in manufacturing that has reached well beyond that industry and has application for every organisation on the face of the planet that has value production as part of its purpose.The Goal introduced the world to the Theory of Constraints (TOC).Wikipedia’s short description of TOC is one of the best:  The Theory of Constraints is...
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Researchers have significantly improved the performance of lithium-air batteries by unleashing a genetically modified virus onto the microscopic electrode wires.
 
Lithium air batteries have received much attention because they are able to increase power output without having to increase weight, a quality that could allow electric cars to have greater driving range. However, engineers have struggled to find durable materials required for the battery’s electrode, to increase the number of charging cycles the batteries could withstand.
 
Researchers from MIT found a way to overcome this limitation by adding bioengineered viruses to nanowires during the production stage. These nanowires are about the thickness of one red blood cell.
 
The virus, called M13, increases the surface area of the wire, therefore increasing the area where electrochemical activity takes place when the batteries are charged or discharged.
 
The nanowire, with the help of M13, pulls molecules of metal from room temperature water. The virus then binds the metal into specific structural shapes. M13 produces manganese oxide wires, which have the rough, spiky surface required for the desired increase in surface area.
 
The final part of the process is adding a small amount of palladium metal to increase the electrical conductivity of nanowires. These modifications show that it may soon be possible to create a fully functional battery with an energy density two to three times greater than today’s best lithium-air batteries.

Video: Better batteries through biology  
Press release: http://news.discovery.com/tech/biotechnology/mutated-virus-helps-builds-a-better-battery-131114.htm
 
Journal article: http://www.nature.com/ncomms/2013/131113/ncomms3756/abs/ncomms3756.html
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NEW PRODUCT – Adafruit PCB Ruler – 6″
http://www.adafruit.com/products/1554

The first time you soldered up a surface mount component you may have been surprised “these are really small parts!” and there’s dozens of different names too! QFN, TDFN, SOIC, SOP, J-Lead, what do they mean and how can you tell how big they are? Now you can have a reference board at your fingertips, with this snazzy PCB reference ruler.

Measuring approx 1″ x 6″, this standard-thickness FR4, gold plate ruler has the most common component packages you’ll encounter. It also has font size guide, trace-width diagram, and a set of AWG-sized drills so you can gauge your wire thicknesses. Edges are labeled in inches with 1/8th marks and mm with 0.1mm marks.

In stock and shipping now!
http://www.adafruit.com/products/1554

#tools   #handtools  
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How to make ceramics that bend without breaking: New materials developed at #MIT could lead to actuators on a chip and self-deploying medical devices. More: http://mitne.ws/15wtuGp

Graphic: When subjected to a load, the molecular structure of the ceramic material in this study deforms rather than cracking. When heated, it then returns to its original shape. Though they have the same chemical composition, the two molecular configurations correspond to different natural minerals, called austenite and martensite. Credit: Lai et al
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Claudia Mihaela Dung

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Christie Marie Sheldon's summary on the most interesting studies that question what we think of consciousness
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A successful business usually starts with a smart idea. The EU is helping to fund research that brings these ideas to life. Check out success stories from all across the #EU here: http://ow.ly/qDwFP and big opportunities for #SMEs under  H2020, nearly €9 billion earmarked over 7 years. http://bit.ly/17Hv3G3  First calls in December! 
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Essence of Art # 03 ♥
16th Nov¹³ Fri 8:42pm

.. “ The picture is a poem without words.”


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Tardis Regions in Space

We all know about the Doctor's Tardis.  It is bigger on the inside than it looks.  Well that may not be fiction after all.  The explanation is a bit complicated, well more than a bit.  It pushes my poor brain to the limit to try to understand it. 

A team of cosmologists in Finland and Poland propose that the observed acceleration of the expansion of the universe, usually explained by dark energy or modified laws of gravity, may actually be the result of regions of space-time that are larger on the inside than they appear from the outside. The researchers have dubbed these "Tardis regions."  ⓐ

In 1998 scientists discovery that the expansion of the universe has been accelerating for the past five billion years . This result won the 2011 Nobel Prize.  

This acceleration of the expansion of the universe can be explained by:
In terms of conventional cosmological theory, it calls for the existence of a "dark energy," an energy field permeating the universe. However, because gravity attracts normal mass-energy, dark energy would have to have a negative energy density, something unknown as yet in nature. In addition, roughly 75 percent of the contents of the universe have to be made up of dark energy to get the observed acceleration of expansion. Even though dark energy provides a reasonable description of the universal acceleration, its value as an explanation is still controversial.  ⓐ

Professors Rasanen, and Szybkab, of the University of Helsinki and the Jagellonian University at Krakow, together with Rasanen's graduate student Mikko Lavinto, decided to investigate another possibility.  ⓐ

Rasanen's research team decided to examine a model universe having a structure closer to ours, in an attempt to look for alternate explanations of the accelerating expansion we see. They took an FLRW metric filled with a uniform density of dust, and converted it into a Swiss cheese model but cutting random holes in it. This has the effect of making the model inhomogeneous and non-isotropic (except very far away), and hence the Swiss cheese model looks more like our own Universe, save for the fact that our Universe does not seem to be full of holes.   ⓐ

While Swiss cheese is delicious, a universe with holes is not. To rectify this, Rasanen's team filled in the holes with plugs made from dust-filled exact solutions of Einstein's equation. These plugs are a reasonable model of the region near a sizable body, such as a galaxy. By putting the plugs in the holes, and then smoothing the intersections between them, they obtained a rather uniform spacetime with a lot of smaller blobs of matter dispersed throughout it  a (very) simple analog to the structure of the universe in which we live. ⓐ

Rasanen's team made the plugs from a model in which the spatial parts essentially fold in on themselves as the spacetime evolves.
such folds increase the length of a path passing through the plug without changing the external dimensions of the plug. For some such plugs, the length of a path through the plug becomes longer throughout the life of the Universe.  ⓐ

Although the Tardis regions expand faster than the surrounding dust space, this does not change their apparent size from outside, so at first glance it is difficult to see how this accelerates the expansion of the universe. The key is that when an observer looks at a distant object in a plugged Swiss cheese space, the light they see has passed through a number of plugs, the number increasing the further away the object. As the length of a path through a Tardis region rapidly becomes larger as time goes by, the total length of the path the light followed from an object increases faster than does the space outside the plugs. The result is that the expansion of the universe appears to be accelerating with time, without additional influences such as dark matter.  ⓐ  

As a result, the average expansion rate at late times grows relative to the background, i.e. backreaction is significant. The holes fit smoothly into the background, but are larger on the inside than a corresponding background domain: we call them Tardis regions.  ⓑ

So if I understand this correctly, they are explaining the accelerated expansion of the universe not by dark energy but by Tardis regions.  

If you are really into burning out some brain cells the original paper Average expansion rate and light propagation in a cosmological Tardis spacetime.  is below.  
 

ⓐ  http://www.gizmag.com/tardis-regions-spacetime-dark-energy/29292/

ⓑ  http://arxiv.org/pdf/1308.6731.pdf

Image: Gizmag
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Cosmologist Christof Wetterich of the University of Heidelberg has uploaded a paper to the arXiv server in which he claims it's possible that the theory of expansion of the universe might be incorrect. He suggests instead that the redshift observed by researchers here on Earth might be caused by an increase in the mass in the universe.
Cosmologist Christof Wetterich of the University of Heidelberg has uploaded a paper to the arXiv server in which he claims it's possible that the theory of expansion of the universe might be incorrect. He suggests instead that the redshift observed by researchers here on Earth might be caused by ...
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Claudia Mihaela Dung

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Scientists Just Grew Human Heart Tissue That Beats With Total Autonomy

I think my heart just skipped a beat ... Is this awesome or WHAT?

( Full Story - http://goo.gl/LjJyW0 )

#Science   #Medicine   #3DPrinting   #Transplant  
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