Have a deep view into what people are curious about.

🔗 Geology 🔗 Rocks and minerals 🔗 Iceland

Iceland spar, formerly called Iceland crystal (Icelandic: silfurberg [ˈsɪlvʏrˌpɛrk], lit. 'silver-rock') and also called optical calcite, is a transparent variety of calcite, or crystallized calcium carbonate, originally brought from Iceland, and used in demonstrating the polarization of light.

🔗 United States 🔗 Spaceflight 🔗 Automobiles

Elon Musk's Tesla Roadster is an electric sports car that served as the dummy payload for the February 2018 Falcon Heavy test flight and became an artificial satellite of the Sun. "Starman", a mannequin dressed in a spacesuit, occupies the driver's seat. The car and rocket are products of Tesla and SpaceX, respectively, both companies founded by Elon Musk. The 2008-model Roadster was previously used by Musk for commuting to work and is the only production car in space.

The car, mounted on the rocket's second stage, acquired enough velocity to escape Earth's gravity and enter an elliptical heliocentric orbit crossing the orbit of Mars. The orbit reaches a maximum distance from the Sun at aphelion of 1.66 astronomical units (au). During the early portion of the voyage outside the Earth's atmosphere, live video was transmitted back to the mission control center and live-streamed for slightly over four hours.

Advertising analysts noted Musk's sense of brand management and use of new media for his decision to launch a Tesla into space. While some commenters voiced concern that the car contributed to space debris, others saw it as a work of art. Musk explained he wanted to inspire the public about the "possibility of something new happening in space" as part of his larger vision for spreading humanity to other planets.

🔗 Psychology 🔗 Education

Bloom's taxonomy is a set of three hierarchical models used to classify educational learning objectives into levels of complexity and specificity. The three lists cover the learning objectives in cognitive, affective and sensory domains. The cognitive domain list has been the primary focus of most traditional education and is frequently used to structure curriculum learning objectives, assessments and activities.

The models were named after Benjamin Bloom, who chaired the committee of educators that devised the taxonomy. He also edited the first volume of the standard text, Taxonomy of Educational Objectives: The Classification of Educational Goals.

🔗 Psychology 🔗 Disability

Working memory training is intended to improve a person's working memory. Working memory is a central intellectual faculty, linked to IQ, ageing, and mental health. It has been claimed that working memory training programs are effective means, both for treating specific medical conditions associated with working memory deficit, and for general increase in cognitive capacity among healthy neurotypical adults.

Individual studies of the topic show different, and sometime contradictory, results, and as one meta study puts it, asking the question “Does cognitive training improve intelligence?” is as inappropriate as asking “Does medicine cure disease?”, since none of them specify which particular intervention (which medicine or working memory training program) is being evaluated, for alleviating which condition is it applied (ADHD, stroke, general cognitive improvement etc.), and under what circumstances is it administered (selection criteria, adherence rate, outcome variables etc.).

In an influential metastudy from 2012, highly critical to cognitive training, analysed 23 studies with 30 group comparisons, and concluded that clinical memory training programs produce reliable short-term improvements in working memory skills in children and adults with ADHD, but also that there is no evidence that such effects can be maintained long-term without additional follow-up training. Three years later, another metastudy reached the opposite conclusion, that working memory training does have consistent and useful effects, not just on the type of working memory tests that are practiced, but also at other non-trained tasks and everyday life. Since then, a range of additional clinical experiments have been completed, with larger sample sizes, clearly defined control groups, and more uniform treatment of outcome variables. While the evidence is still far from unanimous, there are several experimental studies of working memory training that have shown beneficial effects for people with ADHD, those who have suffered stroke or traumatic brain injury, children who have undergone cancer treatment, as well as for normally developing children.

Noblesse oblige (; French: [nɔblɛs ɔbliʒ]) is a French expression used in English meaning that nobility extends beyond mere entitlements and requires the person who holds such a status to fulfill social responsibilities. For example, a primary obligation of a nobleman could include generosity towards those around him.

The Oxford English Dictionary states that the term suggests "noble ancestry constrains to honourable behaviour; privilege entails responsibility."

The Dictionnaire de l'Académie française defines it thus:

1. Whoever claims to be noble must conduct himself nobly.
2. (Figuratively) One must act in a fashion that conforms to one's position and privileges with which one has been born, bestowed and/or has earned.

🔗 Books 🔗 Psychology

The Origin of Consciousness in the Breakdown of the Bicameral Mind is the 1976 book by the Princeton psychologist, psychohistorian and consciousness theorist Julian Jaynes (1920-1997). The book addresses the problematic nature of consciousness – “the ability to introspect” – which in Jaynes’s view must be distinguished from sensory awareness and other processes of cognition. Jaynes presents his proposed solution: that consciousness is a “learned behavior” based more on language and culture than on biology; this solution, in turn, points to the origin of consciousness in ancient human history rather than in metaphysical or evolutionary processes; furthermore, archaeological and historical evidence indicates that prior to the “learning” of consciousness, human mentality was what Jaynes called "the bicameral mind" – a mentality based on verbal hallucination.

The first edition was released in January 1977 in English. Two later editions, in 1982 and in 1990, were released by Jaynes with additions but without alterations. It was Jaynes's only book, and it is still in print, in several languages. In addition to numerous reviews and commentaries, there are several summaries of the book's material, for example, in the journal Behavioral and Brain Sciences, in lectures and discussions published in Canadian Psychology, and in Art/World.

🔗 Dentistry

Palmer notation (sometimes called the "Military System" and named for 19th-century American dentist Dr. Corydon Palmer from Warren, Ohio) is a dental notation (tooth numbering system). Despite the adoption of the FDI World Dental Federation notation (ISO 3950) in most of the world and by the World Health Organization, the Palmer notation continued to be the overwhelmingly preferred method used by orthodontists, dental students and practitioners in the United Kingdom as of 1998.

The notation was originally termed the Zsigmondy system after Hungarian dentist Adolf Zsigmondy, who developed the idea in 1861 using a Zsigmondy cross to record quadrants of tooth positions. Adult teeth were numbered 1 to 8, and the child primary dentition (also called deciduous, milk or baby teeth) were depicted with a quadrant grid using Roman numerals I, II, III, IV, V to number the teeth from the midline. Palmer changed this to A, B, C, D, E, which made it less confusing and less prone to errors in interpretation.

The Palmer notation consists of a symbol (⏌⎿ ⏋⎾) designating in which quadrant the tooth is found and a number indicating the position from the midline. Adult teeth are numbered 1 to 8, with deciduous (baby) teeth indicated by a letter A to E. Hence the left and right maxillary central incisor would have the same number, "1", but the right one would have the symbol "⏌" underneath it, while the left one would have "⎿".

🔗 Computing 🔗 Computer science 🔗 Cryptography 🔗 Cryptography/Computer science

Diffie–Hellman key exchange is a method of securely exchanging cryptographic keys over a public channel and was one of the first public-key protocols as conceived by Ralph Merkle and named after Whitfield Diffie and Martin Hellman. DH is one of the earliest practical examples of public key exchange implemented within the field of cryptography.

Traditionally, secure encrypted communication between two parties required that they first exchange keys by some secure physical means, such as paper key lists transported by a trusted courier. The Diffie–Hellman key exchange method allows two parties that have no prior knowledge of each other to jointly establish a shared secret key over an insecure channel. This key can then be used to encrypt subsequent communications using a symmetric key cipher.

Diffie–Hellman is used to secure a variety of Internet services. However, research published in October 2015 suggests that the parameters in use for many DH Internet applications at that time are not strong enough to prevent compromise by very well-funded attackers, such as the security services of large governments.

The scheme was published by Whitfield Diffie and Martin Hellman in 1976, but in 1997 it was revealed that James H. Ellis, Clifford Cocks, and Malcolm J. Williamson of GCHQ, the British signals intelligence agency, had previously shown in 1969 how public-key cryptography could be achieved.

Although Diffie–Hellman key agreement itself is a non-authenticated key-agreement protocol, it provides the basis for a variety of authenticated protocols, and is used to provide forward secrecy in Transport Layer Security's ephemeral modes (referred to as EDH or DHE depending on the cipher suite).

The method was followed shortly afterwards by RSA, an implementation of public-key cryptography using asymmetric algorithms.

Expired U.S. Patent 4,200,770 from 1977 describes the now public-domain algorithm. It credits Hellman, Diffie, and Merkle as inventors.

🔗 Home Living

The Monobloc (From mono- (“one”) + bloc (“block”), meaning an object forged in a single piece) chair is a lightweight stackable polypropylene chair, usually white in colour, often described as the world's most common plastic chair.

Based on original designs by the Canadian designer D.C. Simpson in 1946, variants of the one-piece plastic chair went into production with Allibert Group and Grosfillex Group in the 1970s. They were inspired by the Chair Universal 4867 design by Joe Colombo in 1965, but no patents were filed for a monobloc chair design. Since then, millions have been manufactured in countries including Russia, Taiwan, Australia, Mexico, the United States, Italy, France, Germany, Morocco, Turkey, Israel, India and China. The Monobloc chair is named because it is injection moulded from thermoplastic polypropylene, the granules being heated to about 220 degrees Celsius, and the melt injected into a mold. The gate of the mould is usually located in the seat, so ensuring smooth flow to all parts of the tool.

Close to a billion Monoblocs have been sold in Europe alone, with one Italian manufacturer producing over ten million a year. Many design variants of the basic idea exist. The chairs cost approximately $3.50 to produce, making them affordable across the world. The stackable design aids setting up large gatherings and storage of the chairs afterwards. In developing countries with high population growth, monoblocs are used to seat thousands of church attendees at a time. Social theorist Ethan Zuckerman describes the chair as having achieved a cultural global ubiquity.

🔗 United States 🔗 Food and drink 🔗 Popular Culture 🔗 United States/Kentucky 🔗 United States/Louisville

The KFC Original Recipe is a secret mix of ingredients that fast food restaurant chain KFC uses to produce fried chicken.

By the very late 1930s, Harland Sanders' gas station in Corbin, Kentucky was so well known for its fried chicken that Sanders decided to remove the gas pumps and build a restaurant and motel in their place. While perfecting his secret recipe with 11 herbs and spices, Sanders found that pan frying chicken was too slow, requiring 30 minutes per order. Deep frying the chicken required half the time but produced dry, unevenly done chicken. In 1939, he found that using a pressure fryer produced tasty, moist chicken in eight or nine minutes. By July 1940, Sanders finalized what came to be known as his Original Recipe.

After Sanders formed a partnership with Pete Harman, they began marketing the chicken in the 1950s as Kentucky Fried Chicken; the company shipped the spices already mixed to restaurants to preserve the recipe's secrecy. He claimed that the ingredients "stand on everybody's shelf".

Sanders used vegetable oil for frying chicken. By 1993, for economic reasons, many KFC outlets had chosen to use a blend of palm and soybean oil. In Japan, the oil used is mainly the more expensive cottonseed and corn oil, as KFC Japan believes that this offers superior taste quality.