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🔗 Aviation

A cyclorotor, cycloidal rotor, cycloidal propeller or cyclogiro, is a fluid propulsion device that converts shaft power into the acceleration of a fluid using a rotating axis perpendicular to the direction of fluid motion. It uses several blades with a spanwise axis parallel to the axis of rotation and perpendicular to the direction of fluid motion. These blades are cyclically pitched twice per revolution to produce force (thrust or lift) in any direction normal to the axis of rotation. Cyclorotors are used for propulsion, lift, and control on air and water vehicles. An aircraft using cyclorotors as the primary source of lift, propulsion, and control is known as a cyclogyro or cyclocopter. A unique aspect is that it can change the magnitude and direction of thrust without the need of tilting any aircraft structures. The patented application, used on ships with particular actuation mechanisms both mechanical or hydraulic, is named after German company Voith Turbo.

🔗 Computing 🔗 Google

Google Sidewiki was a web annotation tool from Google, launched in September 2009 and discontinued in December 2011. Sidewiki was a browser extension that allowed anyone logged into a Google Account to make and view comments about a given website in a sidebar. Despite the name, the tool was not a collaborative wiki, though the comments were editable by the author.

🔗 Linguistics 🔗 Writing systems

Although people in many parts of the world share common alphabets and numeral systems (versions of the Latin writing system are used throughout the Americas, Australia, and much of Europe and Africa; the Arabic numerals are nearly universal), styles of handwritten letterforms vary between individuals, and sometimes also vary systematically between regions.

🔗 Psychology 🔗 Sociology 🔗 Media

The spiral of silence theory is a political science and mass communication theory proposed by the German political scientist Elisabeth Noelle-Neumann. It states that an individual's perception of the distribution of public opinion influences that individual's willingness to express their own opinions, which in turn affects the perceptions and, ultimately, willingness of others to express their opinions. The main idea is that people influence each other's willingness to express opinions through social interaction. According to the spiral of silence theory, individuals will be more confident and outward with their opinion when they notice that their personal opinion is shared throughout a group. But if the individual notices that their opinion is unpopular with the group they will be more inclined to be reserved and remain silent. In other words, from the individual's perspective, "not isolating himself is more important than his own judgement", meaning his perception of how others in the group perceive him is more important to himself than the need for his opinion to be heard.

According to Glynn (1995), "the major components of the spiral of silence include (1) an issue of public interest; (2) divisiveness on the issue; (3) a quasi-statistical sense that helps an individual perceive the climate of opinion as well as estimate the majority and minority opinion; (4) 'fear of isolation' from social interaction "(though, whether this is a causal factor in the willingness to speak out is contested)"; (5) an individual's belief that a minority (or 'different') opinion isolates oneself from others; and (6) a 'hardcore' group of people whose opinions are unaffected by others' opinions."

🔗 Novels 🔗 Slovenia

Alamut is a novel by Vladimir Bartol, first published in 1938 in Slovenian, dealing with the story of Hassan-i Sabbah and the Hashshashin, and named after their Alamut fortress. The maxim of the novel is "Nothing is an absolute reality; all is permitted". This book was one of the inspirations for the video game series Assassin's Creed.

Bartol first started to conceive the novel in the early 1930s, when he lived in Paris. In the French capital, he met with the Slovene literary critic Josip Vidmar, who introduced him to the story of Hassan-i Sabbah. A further stimulation for the novel came from the assassination of Alexander I of Yugoslavia perpetrated by Croatian and Bulgarian radical nationalists, on the alleged commission of the Italian fascist government. When it was originally published, the novel was sarcastically dedicated to Benito Mussolini.

🔗 United States 🔗 Biography 🔗 Children's literature 🔗 Chicago 🔗 Biography/Actors and Filmmakers

Alan Wolf Arkin (March 26, 1934 – June 29, 2023) was an American actor, director, and screenwriter best known for his performances on stage and screen. Throughout his career spanning eight decades, he received various accolades, including an Academy Award, two Screen Actors Guild Awards, a British Academy Film Award, a Golden Globe Award, and a Tony Award.

Arkin began his career on the Broadway stage, starring in Enter Laughing in 1963 for which he won the Tony Award for Best Featured Actor in a Play, and the comedic play Luv (1964). For his work directing The Sunshine Boys, he was nominated for the Tony Award for Best Direction of a Play in 1973. He gained stardom acting in The Russians Are Coming, the Russians Are Coming (1966), Wait Until Dark (1967), The Heart Is a Lonely Hunter (1968), Popi (1969), Catch-22 (1970), The In-Laws (1979), Edward Scissorhands (1990), Glengarry Glen Ross (1992), Grosse Point Blank (1997), Thirteen Conversations About One Thing (2001), Sunshine Cleaning (2007), Get Smart (2008), and Argo (2012). For his performance in Little Miss Sunshine, he won the Academy Award for Best Supporting Actor, and BAFTA Award for Best Actor in a Supporting Role.

He was also known for his roles on television including his performances as Leon Felhendler in Escape from Sobibor (1987), and as Harry Rowen in The Pentagon Papers (2003) which he earned Primetime Emmy Award for Outstanding Lead Actor in a Limited or Series or Movie nominations. From 2015 to 2016 he voiced J.D. Salinger in the Netflix animated series BoJack Horseman. From 2018 to 2019 he starred in the Netflix comedy series The Kominsky Method, earning two consecutive Primetime Emmy Award for Outstanding Supporting Actor in a Comedy Series nominations.

🔗 Physics 🔗 Philosophy 🔗 Philosophy/Philosophy of science 🔗 Philosophy/Metaphysics

In physics and cosmology, the mathematical universe hypothesis (MUH), also known as the ultimate ensemble theory, is a speculative "theory of everything" (TOE) proposed by cosmologist Max Tegmark.

🔗 Medicine

Pyrotherapy (artificial fever) is a method of treatment by raising the body temperature or sustaining an elevated body temperature using a fever. In general, the body temperature was maintained at 41 °C (105 °F). Many diseases were treated by this method in the first half of the 20th century. In general, it was done by exposing the patient to hot baths, warm air, or (electric) blankets. The technique reached its peak of sophistication in the early 20th century with malariotherapy, in which Plasmodium vivax, a causative agent of malaria, was allowed to infect already ill patients in order to produce intense fever for therapeutic ends. The sophistication of this approach lay in using effective anti-malarial drugs to control the P. vivax infection, while maintaining the fever it causes to the detriment of other, ongoing, and then-incurable infections present in the patient, such as late-stage syphilis. This type of pyrotherapy was most famously used by psychiatrist Julius Wagner-Jauregg, who won the Nobel Prize for Medicine in 1927 for his elaboration of the procedure in treating neurosyphilitics.

🔗 Mathematics 🔗 Economics 🔗 Game theory

A Vickrey auction or sealed-bid second-price auction (SBSPA) is a type of sealed-bid auction. Bidders submit written bids without knowing the bid of the other people in the auction. The highest bidder wins but the price paid is the second-highest bid. This type of auction is strategically similar to an English auction and gives bidders an incentive to bid their true value. The auction was first described academically by Columbia University professor William Vickrey in 1961 though it had been used by stamp collectors since 1893. In 1797 Johann Wolfgang von Goethe sold a manuscript using a sealed-bid, second-price auction.

Vickrey's original paper mainly considered auctions where only a single, indivisible good is being sold. The terms Vickrey auction and second-price sealed-bid auction are, in this case only, equivalent and used interchangeably. In the case of multiple identical goods, the bidders submit inverse demand curves and pay the opportunity cost.

Vickrey auctions are much studied in economic literature but uncommon in practice. Generalized variants of the Vickrey auction for multiunit auctions exist, such as the generalized second-price auction used in Google's and Yahoo!'s online advertisement programmes (not incentive compatible) and the Vickrey–Clarke–Groves auction (incentive compatible).

🔗 Skepticism 🔗 Neuroscience 🔗 Physiology

The gut–brain axis is the two-way biochemical signaling that takes place between the gastrointestinal tract (GI tract) and the central nervous system (CNS). The term "gut–brain axis" is occasionally used to refer to the role of the gut microbiota in the interplay as well. The "microbiota–gut–brain (MGB or BGM) axis" explicitly includes the role of gut microbiota in the biochemical signaling events that take place between the GI tract and the CNS. Broadly defined, the gut–brain axis includes the central nervous system, neuroendocrine system, neuroimmune systems, the hypothalamic–pituitary–adrenal axis (HPA axis), sympathetic and parasympathetic arms of the autonomic nervous system, the enteric nervous system, vagus nerve, and the gut microbiota.

Chemicals released in the gut by the microbiome can vastly influence the development of the brain, starting from birth. A review from 2015 states that the microbiome influences the central nervous system by “regulating brain chemistry and influencing neuro-endocrine systems associated with stress response, anxiety and memory function”. The gut, sometimes referred to as the “second brain”, functions off of the same type of neural network as the central nervous system, suggesting why it plays a significant role in brain function and mental health.

The bidirectional communication is done by immune, endocrine, humoral and neural connections between the gastrointestinal tract and the central nervous system. More research suggests that the gut microorganisms influence the function of the brain by releasing the following chemicals: cytokines, neurotransmitters, neuropeptides, chemokines, endocrine messengers and microbial metabolites such as "short-chain fatty acids, branched chain amino acids, and peptidoglycans”. The intestinal microbiome can then divert these products to the brain via the blood, neuropod cells, nerves, endocrine cells and more to be determined. The products then arrive at important locations in the brain, impacting different metabolic processes. Studies have confirmed communication between the hippocampus, the prefrontal cortex and the amygdala (responsible for emotions and motivation), which acts as a key node in the gut-brain behavioral axis.

While IBS is the only disease confirmed to be directly influenced by the gut microbiome, many disorders (such as anxiety, autism, depression and schizophrenia) have been linked to the gut-brain axis as well. The impact of the axis, and the various ways in which one can influence it, remains a promising research field which could result in future treatments for psychiatric, age-related, neurodegenerative and neurodevelopmental disorders. For example, according to a study from 2017, “probiotics have the ability to restore normal microbial balance, and therefore have a potential role in the treatment and prevention of anxiety and depression”.

The first of the brain–gut interactions shown, was the cephalic phase of digestion, in the release of gastric and pancreatic secretions in response to sensory signals, such as the smell and sight of food. This was first demonstrated by Pavlov through Nobel prize winning research in 1904.

Scientific interest in the field had already led to review in the second half of the 20th century. It was promoted further by a 2004 primary research study showing that germ-free (GF) mice showed an exaggerated HPA axis response to stress compared to non-GF laboratory mice.

As of October 2016, most of the work done on the role of gut microbiota in the gut–brain axis had been conducted in animals, or on characterizing the various neuroactive compounds that gut microbiota can produce. Studies with humans – measuring variations in gut microbiota between people with various psychiatric and neurological conditions or when stressed, or measuring effects of various probiotics (dubbed "psychobiotics" in this context) – had generally been small and were just beginning to be generalized. Whether changes to the gut microbiota are a result of disease, a cause of disease, or both in any number of possible feedback loops in the gut–brain axis, remained unclear.