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¿Se acercan los primeros “discos duros” líquidos? [742]

de System Administrator - miércoles, 13 de agosto de 2014, 21:05
 

¿Se acercan los primeros “discos duros” líquidos?

por Marcos Merino

Un equipo de investigadores de ciencia de materiales liderados por Sharon Glotzer y David Pino ha dado los primeros pasos hacia la obtención de una clase de materia blanda que podría ser usada como medio viable de almacenamiento informático (contando, además, con una extraordinaria capacidad de almacenamiento). Cuando hablamos de “materia blanda” nos referimos tanto a líquidos como a espumas, polímeros, o materiales similares: lo relevante es que todos ellos tienen en común el poseer comportamientos físicos previsibles a diferentes temperaturas.

De acuerdo a lo avanzado por esta investigación, se podrían usar nanopartículas suspendidas en líquido para codificar los mismos unos y ceros que hoy en día almacenamos en los discos duros; la cantidad de este material necesaria para almacenar 1 Tb de información cabría en una cucharada. Estaríamos aquí ante una suspensión coloidal: las partículas no se disuelven de forma permanente en la solución, sino que conservan sus propiedades esperadas, en este caso, la de reorientarse de forma previsible en presencia de calor. Otros ejemplos de coloides pueden ser el humo, la espuma de afeitado o la gelatina.

Lo que convierte un curioso movimiento de partículas dentro de un fluido en la posibilidad de almacenar ingentes cantidades de datos en un vaso es el hecho de que la combinación más simple de dichas partículas (cuatro de ellas unidas por una partícula central, formando un nanoclúster) sólo tiene dos configuraciones distinguibles (y alterables mediante la aplicación de energía térmica), que además son ‘quirales‘ -es decir, no son superponibles con su imagen especular-, lo que permite distinguirlas incluso cuando están flotando libremente. Ello es lo que permite leer ambos estados como 1 o 0,convirtiendo a cada agrupación de nanopartículas en un único bit de datos.

Quedaría, en todo caso, mucho trabajo por delante: bloquear de manera confiable los racimos de nanoclústers dentro de un gran volumen de líquido (bautizado como ‘coloide digital’), y luego leer estos datos de manera rápida. Por ello, cabe pensar que los discos seguirán siendo ‘duros’ por unos años todavía.

En el pasado ya ha habido avances en el uso de la nanotecnología para almacenar datos: IBM consiguió almacenar un bit de datos en sólo 12 átomos de hierro, mientras que investigadores del Instituto Wyss de Harvard almacenaron con éxito 700 Tb en un sólo gramo de ADN.

Fuente | ExtremeTech
Imagen | Wikimedia

Marcos Merino

Marcos Merino es redactor freelance y consultor de marketing 2.0. Autodidacta, con experiencia en medios (prensa escrita y radio), y responsable de comunicación online en organizaciones sin ánimo de lucro.

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“Inner GPS” Support [1108]

de System Administrator - lunes, 16 de febrero de 2015, 22:55
 

“Inner GPS” Support

Grid cells—the neurons that function as a spatial navigation system—require input from another set of neurons, a rat study shows.

By Anna Azvolinsky 

 

Neuron firing map (top row) and spatial maps of grid cell firing in control (middle, bottom rows) with no neuronal inactivation (left column) inactivation with lidocaine (middle column), and recovery post-lidocaine (right column).

SHAWN WINTER, BENJAMIN CLARK, DARTMOUTH COLLEGE

Forming a network that’s known as the brain’s “inner GPS,” neurons called grid cells help rodents and humans navigate. Now, by studying rats, researchers at Dartmouth College in New Hampshire have found that these neurons receive spatial information from head direction cells in the thalamus. Theirs are the first experimental results demonstrating that the flow of information from head direction cells to grid cells is important for grid cell functioning. The results, published today (February 5) in Science, confirm predictions previously generated using computational models.

While it was known that grid cells may need input from place cells in the hippocampus, it was not known whether head direction cells supported grid cell function. “These experiments now show a strong link between the head direction and the grid cells,” said Stefan Leutgeb, a neurobiologist at the University of California, San Diego, who was not involved in the work.

“The findings are expected but still important in that they verify core ideas of current models of how grid cell patterns are generated and maintained,” Edvard Moser of the Norwegian University of Science and Technology (NTNU), who—along with his wife, May-Britt, also of NTNU, and John O’Keefe of University College London—won the 2014 Nobel Prize in Physiology or Medicine for his work on grid cells, told The Scientist in an e-mail.

Today, a decade after grid cells were first identified, “we don’t really know what these cells are doing, functionally,” said study coauthor Jeffrey Taube, a professor of psychological and brain sciences at Dartmouth. Each grid cell fires when an animal is in a certain location in a space. The compilation of these locations produces a grid-like map for each cell.

Along with postdoctoral fellow Shawn Winter and then graduate student Benjamin Clark, Taube severed the connections between head direction and grid cells in live rats by infusing the sodium channel inhibitor lidocaine into the thalamus. Lidocaine temporarily reduced or eliminated the grid-like pattern of grid cell firing in the animals, suggesting that signals from head cells are necessary for grid cells to function. Permanently damaging less than 85 percent of the thalamus region containing head direction cells still resulted in grid-like firing, but when more than 85 percent of this area was damaged, no cells with grid activity were found.

The researchers also found that the grid-like firing pattern was also disrupted in the presence of EEG-recorded theta brain waves. These sinusoidal waves of electrical activity in the brain were previously known to be necessary for the firing of grid cells. Because injection of the sodium channel inhibitor did not appear to disrupt these waves, the dysregulation of grid cell activity observed as a result can be directly attributed to the loss of the head direction cell signal, said Taube.  

Leutgeb said an important next step will be repeating the lidocaine experiments using a more head direction cell-specific technique to show that these cells are selectively affected.

“The findings support the view that head direction cells are necessary for the periodic firing structure of grid cells,” wrote Moser, who noted he was surprised to see that damage to less than 85 percent of the anterior thalamus did not hamper grid cell activity.  “This must imply considerable redundancy in the . . . network. Grid cells and head direction cells may be generated from only a small number of the available directional inputs.”

Moser added that the results in rats raise the question of how important is an animal’s head direction in sensing the body’s movement and whether the body’s directional movement can be inferred from head cell signals or whether additional sensory inputs are required.

S.S. Winter et al., “Disruption of the head direction cell network impairs the parahippocampal grid cell signal,” Science, doi:10.1126/science.1259591, 2015. 



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Wetware [821]

de System Administrator - miércoles, 3 de septiembre de 2014, 19:29
 

Wetware

 

Posted by Margaret Rouse

Wetware refers to programmers, developers, systems administrators, cloud and IT architects and other employees that directly affect how servers, applications, networks and the rest of an IT system functions.

1. Wetware is informal language used to describe the human element of an information technology (IT) architecture.  Wetware can be contrasted withsoftware and hardware, two other components that affect the success or failure of an IT system.

As a noun, wetware is sometimes used as a synonym for human capital or personnel -- the programmers, developers, systems administrators, cloud and IT architects and other employees that directly affect how an IT system functions.  For example, a project manager might say “Before we can move forward with this project, we’ll need more wetware.” 

Wetware is also used as an adjective to describe something that involves human needs or activities. For example, before standardizing on anOpenStack cloud deployment schedule, a DevOps team might hold several wetware meetings to define the project’s scope and budget. Or a team member who requires additional training may be sent for a wetware upgrade. 

Because human beings are less predictable – and sometimes less reliable -- than software or hardware, the term wetware is sometimes used in a derogatory manner as a synonym for human error, as in the sentence “After examining the audit logs, we concluded the problem had to be wetware.”  The term meatware may also be used in this way.

2. In neuroscience, wetware is used to describe the human brain’s biologically-based information processing capabilities. The term is also used to refer to biologically-inspired computer systems.

See alsobioroboticsDNA storage

Link: http://searchdatacenter.techtarget.com

Wetware Technology Movies - Matrix

The ultimate in immersive virtual environments based on an intensely invasive brain computer interface ...

The first Matrix film was an amazing use of wetware technology, very thought provoking. Note that I am talking about the first movie, not the two silly sequels.

Wireheading is not that outrageous, medical devices for seizure prevention is on the cusp of mainstream at this point. Certainly not a fully interactive simulation with high bandwidth bi-directional communication, but all steps forward are important. Although I am not sure how long it will take for the chrome head port to catch on in the populace.

 

Link: http://wetwarehacker.blogspot.com/2010/03/wetware-technology-movies-matrix.html

 


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