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🔗 Tadoma

🔗 Disability 🔗 Deaf

Tadoma is a method of communication used by deafblind individuals, in which the deafblind person places their little finger on the speaker's lips and their fingers along the jawline. The middle three fingers often fall along the speaker's cheeks with the little finger picking up the vibrations of the speaker's throat. It is sometimes referred to as tactile lipreading, as the deafblind person feels the movement of the lips, as well as vibrations of the vocal cords, puffing of the cheeks and the warm air produced by nasal sounds such as 'N' and 'M'. There are variations in the hand positioning, and it is a method sometimes used by people to support their remaining hearing.

In some cases, especially if the speaker knows sign language, the deaf-blind person may use the Tadoma method with one hand, to feel the speaker's face, and, at the same time, the deaf-blind person may use their other hand to feel the speaker sign the same words. In this way, the two methods reinforce each other, giving the deaf-blind person a better chance of understanding what the speaker is trying to communicate.

In addition, the Tadoma method can provide the deaf-blind person with a closer connection with speech than they might otherwise have had. This can, in turn, help them to retain speech skills that they developed before going deaf, and in special cases, to learn how to speak brand new words.

It is a difficult method to learn and use, and is rarely used nowadays. However, a small number of deafblind people successfully use Tadoma in everyday communication.

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🔗 Mponeng Gold Mine

🔗 Mining 🔗 South Africa

Mponeng is a gold mine in South Africa's Gauteng province. Previously known as Western Deep Levels #1 Shaft, the underground and surface works were commissioned in 1987. It extends over 4 kilometres (2.5 mi) below the surface, and is considered to be one of the most substantial gold mines in the world. It is also currently the world's deepest mine from ground level, reaching a depth of 4 km (2.5 mi) below ground level. The trip from the surface to the bottom of the mine takes over an hour.

Over 5400 metric tonnes of rock are excavated from Mponeng each day. At a price of $19.4 per gram of gold, the mine only needs to extract 10 grams of gold per ton excavated to remain profitable. The mine contains at least two gold reefs, with the deepest one metre thick.

Harmony Gold purchased Mponeng from AngloGold Ashanti in September 2020. Along with AGA's Mine Waste Solutions, Harmony paid approximately $300m.

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🔗 Valid Email Addresses

🔗 Technology 🔗 Internet 🔗 Computing 🔗 Computing/Networking

An email address identifies an email box to which email messages are delivered. A wide variety of formats were used in early email systems, but only a single format is used today, following the specifications developed for Internet mail systems since the 1980s. This article uses the term email address to refer to the addr-spec defined in RFC 5322, not to the address that is commonly used; the difference is that an address may contain a display name, a comment, or both.

An email address such as John.Smith@example.com is made up of a local-part, an @ symbol, then a case-insensitive domain. Although the standard requires the local part to be case-sensitive, it also urges that receiving hosts deliver messages in a case-independent fashion, e.g., that the mail system at example.com treat John.Smith as equivalent to john.smith; some mail systems even treat them as equivalent to johnsmith. Mail systems often limit their users' choice of name to a subset of the technically valid characters, and in some cases also limit which addresses it is possible to send mail to.

With the introduction of internationalized domain names, efforts are progressing to permit non-ASCII characters in email addresses.

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🔗 Terence Tao

🔗 Biography 🔗 Mathematics 🔗 Australia 🔗 Biography/science and academia

Terence Chi-Shen Tao (born 17 July 1975) is an Australian-American mathematician who has worked in various areas of mathematics. He currently focuses on harmonic analysis, partial differential equations, algebraic combinatorics, arithmetic combinatorics, geometric combinatorics, probability theory, compressed sensing and analytic number theory. As of 2015, he holds the James and Carol Collins chair in mathematics at the University of California, Los Angeles.

Tao was a recipient of the 2006 Fields Medal and the 2014 Breakthrough Prize in Mathematics. He is also a 2006 MacArthur Fellow. Tao has been the author or co-author of 275 research papers.

Tao is the second mathematician of Han Chinese descent to win the Fields medal after Shing-Tung Yau, and the first Australian citizen to win the medal.

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🔗 Mars Trilogy

🔗 Novels 🔗 Novels/Science fiction 🔗 Science Fiction 🔗 Solar System/Mars 🔗 Solar System

The Mars trilogy is a series of science fiction novels by Kim Stanley Robinson that chronicles the settlement and terraforming of the planet Mars through the personal and detailed viewpoints of a wide variety of characters spanning almost two centuries. Ultimately more utopian than dystopian, the story focuses on egalitarian, sociological, and scientific advances made on Mars, while Earth suffers from overpopulation and ecological disaster.

The three novels are Red Mars (1992), Green Mars (1993), and Blue Mars (1996). The Martians (1999) is a collection of short stories set in the same fictional universe. Red Mars won the BSFA Award in 1992 and Nebula Award for Best Novel in 1993. Green Mars won the Hugo Award for Best Novel and Locus Award for Best Science Fiction Novel in 1994. Blue Mars also won the Hugo and Locus Awards in 1997.

Icehenge (1984), Robinson's first novel about Mars, is not set in this universe but deals with similar themes and plot elements. The trilogy shares some similarities with Robinson's more recent novel 2312 (2012); for instance, the terraforming of Mars and the extreme longevity of the characters in both novels.

🔗 Topological quantum computer

🔗 Mathematics 🔗 Physics

A topological quantum computer is a theoretical quantum computer that employs two-dimensional quasiparticles called anyons, whose world lines pass around one another to form braids in a three-dimensional spacetime (i.e., one temporal plus two spatial dimensions). These braids form the logic gates that make up the computer. The advantage of a quantum computer based on quantum braids over using trapped quantum particles is that the former is much more stable. Small, cumulative perturbations can cause quantum states to decohere and introduce errors in the computation, but such small perturbations do not change the braids' topological properties. This is like the effort required to cut a string and reattach the ends to form a different braid, as opposed to a ball (representing an ordinary quantum particle in four-dimensional spacetime) bumping into a wall. Alexei Kitaev proposed topological quantum computation in 1997. While the elements of a topological quantum computer originate in a purely mathematical realm, experiments in fractional quantum Hall systems indicate these elements may be created in the real world using semiconductors made of gallium arsenide at a temperature of near absolute zero and subjected to strong magnetic fields.

🔗 Eazel, ex-Apple led Linux startup

🔗 Companies 🔗 Technology 🔗 Apple Inc. 🔗 Computing 🔗 Computing/Software 🔗 Computing/Free and open-source software 🔗 Linux

Eazel was an American software company operating from 1999 to 2001 in Palo Alto and then Mountain View, California. The company's flagship product is the Nautilus file manager for the GNOME desktop environment on Linux, which was immediately adopted and maintained by the free software movement. As the core of Eazel's business model, it is an early example of cloud storage services in the form of personal file storage, transparently and portably stored on the Internet. Renamed to Files, this application continues to be a centerpiece of some free Linux-based desktop environments.

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🔗 Enteric nervous system

🔗 Animal anatomy 🔗 Neuroscience 🔗 Anatomy 🔗 Anatomy/Neuroanatomy

The enteric nervous system (ENS) or intrinsic nervous system is one of the main divisions of the autonomic nervous system (ANS) and consists of a mesh-like system of neurons that governs the function of the gastrointestinal tract. It is capable of acting independently of the sympathetic and parasympathetic nervous systems, although it may be influenced by them. The ENS is also called the second brain.It is derived from neural crest cells.

The enteric nervous system is capable of operating independently of the brain and spinal cord, but does rely on innervation from the autonomic nervous system via the vagus nerve and prevertebral ganglia in healthy subjects. However, studies have shown that the system is operable with a severed vagus nerve. The neurons of the enteric nervous system control the motor functions of the system, in addition to the secretion of gastrointestinal enzymes. These neurons communicate through many neurotransmitters similar to the CNS, including acetylcholine, dopamine, and serotonin. The large presence of serotonin and dopamine in the gut are key areas of research for neurogastroenterologists.

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🔗 The Magic SysRq key

🔗 Computing 🔗 Computing/Software 🔗 Linux

The magic SysRq key is a key combination understood by the Linux kernel, which allows the user to perform various low-level commands regardless of the system's state. It is often used to recover from freezes, or to reboot a computer without corrupting the filesystem. Its effect is similar to the computer's hardware reset button (or power switch) but with many more options and much more control.

This key combination provides access to powerful features for software development and disaster recovery. In this sense, it can be considered a form of escape sequence. Principal among the offered commands are means to forcibly unmount file systems, kill processes, recover keyboard state, and write unwritten data to disk. With respect to these tasks, this feature serves as a tool of last resort.

The magic SysRq key cannot work under certain conditions, such as a kernel panic or a hardware failure preventing the kernel from running properly.

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