Mer (software distribution)

Mer is a free and open-source software distribution, targeted at hardware vendors to serve as a middleware for Linux kernel-based mobile-oriented operating systems. It is a fork of MeeGo.

History

Its aim was initially to provide a completely free alternative to the Maemo operating system, which was able to run on Nokia Internet Tablets such as the N800 and N810 (collectively known as the N8x0 devices).

It was based on Ubuntu 9.04, and with the release of Maemo 5/Fremantle, a new goal emerged: "[To bring] as much of Fremantle as we can get on the N8x0."

Shift to MeeGo

Mer suspended development at release 0.17, since focus had switched to building MeeGo for the N800 and N810 devices. By then, MeeGo was available and supported by a much wider community.

Collapse of MeeGo

The development was silently resumed during the summer of 2011 by a handful of MeeGo developers (some of them previously active in the Mer project), after Nokia changed their strategy in February 2011. These developers were not satisfied with the way MeeGo had been governed behind closed doors especially after Nokia departed, and they were also concerned that MeeGo heavily depended on big companies which could stop supporting it, as was the case when Nokia abandoned MeeGo as part of their new strategy.

Operating system

An operating system (OS) is system software that manages computer hardware and software resources and provides common services for computer programs. The operating system is a component of the system software in a computer system. Application programs usually require an operating system to function.

Time-sharing operating systems schedule tasks for efficient use of the system and may also include accounting software for cost allocation of processor time, mass storage, printing, and other resources.

For hardware functions such as input and output and memory allocation, the operating system acts as an intermediary between programs and the computer hardware, although the application code is usually executed directly by the hardware and frequently makes system calls to an OS function or is interrupted by it. Operating systems are found on many devices that contain a computer  from cellular phones and video game consoles to web servers and supercomputers.

Examples of popular desktop operating systems include Apple OS X, Linux and its variants, and Microsoft Windows. So-called mobile operating systems include Android and iOS.

Monomer

A monomer (/ˈmɒnəmər/ MON-ə-mər) (mono-, "one" + -mer, "part") is a molecule that may bind chemically or supramolecularly to other molecules to form a (supramolecular) polymer. The process by which monomers combine end to end to form a polymer is called polymerization. Molecules made of a small number of monomer units (up to a few dozen) are called oligomers. The term "monomeric protein" may also be used to describe one of the proteins making up a multiprotein complex.

Polymer groupings, and the types of monomers that create them:

  • For lipids (Diglycerides, triglycerides)*, the monomers are glycerol and fatty acids.
  • For proteins (Polypeptides), the monomers are amino acids.
  • For Nucleic acids (DNA/RNA), the monomers are nucleotides which is made of a pentose sugar, a nitrogenous base and a phosphate group.
  • For carbohydrates (Polysaccharides specifically and disaccharides—depends), the monomers are monosaccharides.
  • *Diglycerides and triglycerides are made by dehydration synthesis from smaller molecules; this is not the same kind of end-to-end linking of similar monomers that qualifies as polymerization. Therefore, diglycerides and triglycerides are an exception to the term polymer.

    Estrogen receptor alpha

    Estrogen receptor alpha (ERα), also known as NR3A1 (nuclear receptor subfamily 3, group A, member 1), is one of two main types of estrogen receptor, a nuclear receptor that is activated by the sex hormone estrogen. In humans, ERα is encoded by the gene ESR1 (EStrogen Receptor 1).

    Structure

    The estrogen receptor (ER) is a ligand-activated transcription factor composed of several domains important for hormone binding, DNA binding, and activation of transcription.Alternative splicing results in several ESR1 mRNA transcripts, which differ primarily in their 5-prime untranslated regions. The translated receptors show less variability.

    Ligands

    Agonists

    Agonists of ERα selective over ERβ include:

  • Propylpyrazoletriol (PPT)
  • 16α-LE2 (Cpd1471)
  • 16α-IE2
  • SKF-82,958 – also a D1-like receptor full agonist
  • (R,R)-Tetrahydrochrysene ((R,R)-THC) – not actually selective over ERβ, but rather an antagonist instead of an agonist of ERβ
  • Antagonists

    Antagonists of ERα selective over ERβ include:

    System

    A system is a set of interacting or interdependent component parts forming a complex/intricate whole. Every system is delineated by its spatial and temporal boundaries, surrounded and influenced by its environment, described by its structure and purpose and expressed in its functioning.

    The term system may also refer to a set of rules that governs structure and/or behavior. Alternatively, and usually in the context of complex social systems, the term is used to describe the set of rules that govern structure and/or behavior.

    Etymology

    The term "system" comes from the Latin word systēma, in turn from Greek σύστημα systēma: "whole compounded of several parts or members, system", literary "composition".

    History

    According to Marshall McLuhan,

    "System" means "something to look at". You must have a very high visual gradient to have systematization. In philosophy, before Descartes, there was no "system". Plato had no "system". Aristotle had no "system".

    In the 19th century the French physicist Nicolas Léonard Sadi Carnot, who studied thermodynamics, pioneered the development of the concept of a "system" in the natural sciences. In 1824 he studied the system which he called the working substance (typically a body of water vapor) in steam engines, in regards to the system's ability to do work when heat is applied to it. The working substance could be put in contact with either a boiler, a cold reservoir (a stream of cold water), or a piston (to which the working body could do work by pushing on it). In 1850, the German physicist Rudolf Clausius generalized this picture to include the concept of the surroundings and began to use the term "working body" when referring to the system.

    System (journal)

    System (ISSN 0346-251X) is a peer-reviewed academic journal covering the applications of educational technology and applied linguistics to problems of foreign language teaching and learning. It was established in 1973 and is published quarterly by Elsevier.

    References

    External links

  • Official website
  • Online access at ScienceDirect
  • Physical system

    In physics, a physical system is a portion of the physical universe chosen for analysis. Everything outside the system is known as the environment. The environment is ignored except for its effects on itself. In a physical system, a lower probability states that the vector is equivalent to a higher complexity.

    The split between system and environment is the analyst's choice, generally made to simplify the analysis. For example, the water in a lake, the water in half of a lake, or an individual molecule of water in the lake can each be considered a physical system. An isolated system is one that has negligible interaction with its environment. Often a system in this sense is chosen to correspond to the more usual meaning of system, such as a particular machine.

    In the study of quantum coherence the "system" may refer to the microscopic properties of an object (e.g. the mean of a pendulum bob), while the relevant "environment" may be the internal degrees of freedom, described classically by the pendulum's thermal vibrations.

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