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TOR es un programa que te permite acceder a servidores en internet de forma anonima. Crea una conexion encriptada entre varios servidores de tal forma que en ninguno de ellos se pueda saber nada mas que de cual viene la peticion y a cual va… pero no mas. Es decir, una conexion no se puede rastrear (a no ser que tengas controlados a TODOS los servidores y puedas adivinar que entrada corresponde a que salida… cosa harto complicada puesto que es una red mundial).

Bueno, si os interesa el tema ya pondre mas teoria xq lo tengo que estudiar para la asignatura de computer security.

El caso es q ya que no he dormido nada esta noche (son las 8 y pico d la maniana XD) me he puesto a armar con multitud de cosas, entre ellas esta. Asi que ahi va la explicacion de como hacerlo en linux. Se puede hacer tambien en windows, supongo que no sera muy diferente, pero yo no lo he hecho:

La pagina del proyecto:

http://www.torproject.org/

Primero de todo, instalar los dos programas que vamos a necesitar. El TOR en si y un proxy que mande todas las conexiones a traves del TOR.

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Me ha dado por armar y me he puesto a ver como se pueden encriptar particiones… pero se me ha ocurrido algo mejor: como encriptar una pequeña partición en un USB portátil para poder meter ahí todo lo que quieras y que sea absolutamente imposible que nadie (bueno, lo mismo los de la NSA, pero vamos, en españa ni creo que puedan) pueda ver lo que hay dentro. eso si, dejando otra particion grande sin encriptar para usar el usb de cualquier otra forma, para dejarselo a quien sea, para pasarse archivos unos a otros…lo que sea.

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In the macroscopic world every product is assembled following a blueprint and using a set of assemblers with fixed bricks and boards. In bionanomachines the same principle is used, the assembler is the ribosome and the blueprints is the DNA. There is stored the information needed to construct different kinds of products. The process is simple and universal, for every organism on Earth is done as described in previous chapters.

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The first step to construct any nanomachine is to build the structure. This is not an easy goal, atoms can't be modeled as they were any macroscopic material. They follow a set of rules to interact with another atoms.

Chemists have studied the properties of these atoms and biologists the details of the nanomachines constructed by them. So we have now the knowledge to start creating these new nanomachines. We are going to review the different methods followed to do that.

The natural bionanomachinery is designed for a specific environment. It is done for working inside cells, in a water environment. Without that conditions they don't work properly or don't work at all. The temperature is also important, the most common is 37º. In this environment nanomachines are stable, but they can be destroyed to create new ones with a little energy cost. The life of a nanomachine is between seconds to a year (but this is rare).

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We have now many methods to construct atomic-level machines. Bionanotechnology is the easiest way to do that because there are already nanomachines that can work for us. We don't have to implement everything, atom by atom, by ourselves. To do this we can make those machines to construct molecules they already can make but with some little changes, or we can design nanomachines entirely and make those already implemented workers to make them for us. But this is much more difficult than introduce some changes. For example, if we know a protein that actually works it is easier to give it some new features than to construct a whole protein from scratch because it is still a expensive problem to predict the structure of that protein, and it is important for the operation of that protein.

Recombinant DNA technology is the main process to construct this proteins. It is about changing the DNA that stores the information to create the protein and then wait until ribosoms create it for us. We use two natural enzimes for this, restriction enzimes and DNA ligase. Using this we can cut and paste DNA to make our own sequence.Some of this enzimes are being sold in the market, so now it is easy and not so expensive to manipulate DNA. There is a variety of natural biomolecules for handling DNA, like:Restriction enzimes: isolated from bacteria. Used to cut DNA.DNA ligase: reconnects broken DNA strands.DNA polymerase creates a new DNA strand by using another strand as a template.
Once we have a new DNA we can duplicate it using: DNA cloning and polymerase chain reaction.
The DNA cloning create identical chains. To do this we can inject DNA in a virus and let it to inject the DNA in some bacteria. Then they will duplicate, so we will have a lot of identical cells.
The polymerase chain reaction is for coping a small sample of DNA. We use another bacteria for this. Forte it to duplicate. Using this method we can have as many DNA as we need.
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In a human body there are more than 10,000 types of nanomachines working. But there are one that is the most important for us: the ribosome. That molecule is the one that "construct" proteins from a DNA molecule. This proteins can be enzymes (useful for industry and medicine) or any other type of proteins.But this nanomachines are not like the machines we are used to see in the macroscopic universe. They are not ruled by the usual forces we know (gravity, inertia) as we are. The fact that they are a discrete number of atoms makes them to avoid the effects we know. So gravity can be considered non-existent, same for inertia or friction. But another forces are important, like thermal motion, that are really important in this scale. For example, every molecule inside a cell is supposed to interact in a single second with all of its neighbours. So they are continually being hit by another particles. That makes the structure of the molecules a really important feature.This machines works inside a water enviroment.

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I'm going to write here a little summary of the book "Bionanotechnology: Lessons from Nature" writen by David S. Goodsell. This is an assignment for my major in Bioinformatics in the University of New Orleans. I hope you will enjoy it ;) Please, report any error to correct it. I'm learning and it will be very useful for me :D 

Nanotechnology is the ability to construct any kind of machine with a known and predefined number of atoms, instead of the traditional machines which have an arbitrary number of them. To do this, one idea is to construct an "assembler", a machine capable of making another machines. This machine was supposed to be the great new advance, with it the "2-weeks revolotion" would be possible. This is, if you have a machine able to construct another machines in a very short time you can do whatever you want. But nowadays this is far from our possibilities. That is why the bionanotechnology is important.Biology already has implemented an extraordinary number of nanomachines and has tested them during millions of years within an evolution process. This tests are much more optimized than any test we can make. In each single cell it is a really big number of nanomachines working, and they actually create another nanomachines. So nature has already created those assemblers we are looking for. Using that machines to create our own machines is bionanotechnology.Nanotechnology is a pretty new science. It began with the alchemists, then continued with the chemistry and in the 20th century it has been improved by nuclear physics.In the other hand biology began to play with molecules so the biotechnology started. If we join this two sciences we have a good way to manipulate individual atoms to create everything we can imagine.Thanks to this we can create specific nanomachines to work in many different fields, but the most important is medicine.

Hoy toca una pequeña explicación de cómo se fabrican los circuitos integrados.

Son esas pequeñas cosas negras que hay en las placas verdes que tiene cualquier cacharro electrónico dentro. Los microprocesadores de los ordenadores son lo mismo pero más "a lo bruto". Lo que voy a poner aquí es la forma en que se construían los circuitos nMOS. Siguiendo más o menos el mismo esquema se consiguen los CMOS, que fueron la evolución (bueno, estuvo EDMOS por medio) y probablemente los hayais visto en varios sitios (creo recordar que los 486 tenían de estos). Los CMOS lo mismo los explico con más detalle más adelante.

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Es un problema de dificil solución y visto que os gustan los rompecabezas os lo pongo. No os voy a dar más datos de los necesarios para que no lo mandeis a la mierda demasiado pronto, así, sin prejuicios, lo mismo sale algo interesante. El problema en cuestión es: – Tenemos una serie de ciudades conectadas entre sí por caminos. – Estos caminos son de igual longitud en un sentido que en el otro. – No hay caminos de valor negativo. – No hay dos caminos diferentes entre las mismas dos ciudades. – La distancia entre una ciudad y ella misma es 0 (obvio, pero hay que decirlo). Lo que queremos es encontrar la ruta de menor longitud que pase por todas las ciudades, empezando en una cualquiera y volviendo a esa misma. La ciudad por la que se empieza da igual puesto que el camino mínimo será el mismo desde todas ellas. No se puede pasar dos veces por la misma ciudad (en realidad he visto dos versiones diferentes, esta y otra que dice que no se puede pasar dos veces por el mismo camino aunque sí por la misma ciudad) Creo que con esto ya vale. La solución obvia es la de probar todos los posibles recorridos apuntando el menor de todos ellos para ir comparando con él. Lo que buscamos es una solución diferente de esta puesto que así se convierte en un problema de complejidad exponencial y eso no nos gusta nada. Queremos algo de complejidad polinómica o por el estilo. Pues ahí lo teneis, podeis comentar lo que querais en los comentarios. Podeis preguntar y aportar vuestras soluciones. Suerte con la búsqueda !!