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🔗 Chindōgu

🔗 Japan 🔗 Japan/Culture

Chindōgu (珍道具) is the practice of inventing ingenious everyday gadgets that seem to be ideal solutions to particular problems, but which may cause more problems than they solve. The term is of Japanese origin.

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🔗 Smuggling of silkworm eggs into the Byzantine Empire

🔗 Greece 🔗 Middle Ages 🔗 Middle Ages/History 🔗 Greece/Byzantine world 🔗 Textile Arts

In the mid-6th century CE, two monks, with the support of the Byzantine emperor Justinian I, acquired and smuggled living silkworms into the Byzantine Empire, which led to the establishment of an indigenous Byzantine silk industry that long held a silk monopoly in Europe.

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🔗 Free energy principle

🔗 Biology 🔗 Cognitive science 🔗 Neuroscience

The free energy principle tries to explain how (biological) systems maintain their order (non-equilibrium steady-state) by restricting themselves to a limited number of states. It says that biological systems minimise a free energy function of their internal states, which entail beliefs about hidden states in their environment. The implicit minimisation of variational free energy is formally related to variational Bayesian methods and was originally introduced by Karl Friston as an explanation for embodied perception in neuroscience, where it is also known as active inference.

The free energy principle is that systems—those that are defined by their enclosure in a Markov blanket—try to minimize the difference between their model of the world and their sense and associated perception. This difference can be described as "surprise" and is minimized by continuous correction of the world model of the system. As such, the principle is based on the Bayesian idea of the brain as an “inference engine”. Friston added a second route to minimization: action. By actively changing the world into the expected state, systems can also minimize the free energy of the system. Friston assumes this to be the principle of all biological reaction.. Friston also believes his principle applies to mental disorders as well as to artificial intelligence. AI implementations based on the active inference principle have shown advantages over other methods.

The free energy principle has been criticized for being very difficult to understand, even for experts. Discussions of the principle have also been criticized as invoking metaphysical assumptions far removed from a testable scientific prediction, making the principle unfalsifiable. In a 2018 interview, Friston acknowledged that the free energy principle is not properly falsifiable: "the free energy principle is what it is — a principle. Like Hamilton’s Principle of Stationary Action, it cannot be falsified. It cannot be disproven. In fact, there’s not much you can do with it, unless you ask whether measurable systems conform to the principle."

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🔗 Descent of Inanna into the Underworld

🔗 Ancient Near East 🔗 Assyria 🔗 Mythology 🔗 Project-independent assessment 🔗 Intertranswiki/OKA

The Descent of Inanna into the Underworld (or, in its Akkadian version, Descent of Ishtar into the Underworld) or Angalta ("From the Great Sky") is a Sumerian myth that narrates the descent of the goddess Inanna (Ishtar in Akkadian) into the Underworld to overthrow its ruler, her sister Ereshkigal, the "Queen of the Dead." But following the removal of her adornments, she perishes and her corpse is suspended on a nail. The god Enki intervenes indirectly, restoring Inanna to life. However, on her return journey, Inanna is required to deliver another living human in exchange for her freedom. She selects Dumuzi, her spouse, who is abruptly transported to the Underworld. In response to the pleas of Dumuzi's sister, Geshtinanna, his circumstances are somewhat ameliorated: he is permitted to remain in the Underworld for only a portion of the year, with his sister assuming his role for the remaining duration.

The myth exists in two main versions: one in Sumerian and the other in Akkadian. The Akkadian version was first discovered and translated in the 1860s. The existence of the longer and older Sumerian version was first established in the early 20th century, but it required approximately fifty years for epigraphists to fully reconstruct and translate it.

The story of Descent of Inanna into the Underworld offers insights into Mesopotamian culture through its numerous characters and developed plot. The influence of this culture on subsequent civilizations is evident in the traces of Mesopotamian elements found in Greece, Phoenicia, and the Old Testament. In the 20th century, the story was used by some psychoanalysis theorists to illustrate psychic mechanisms.

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🔗 List of probability distributions

🔗 Lists 🔗 Statistics

Many probability distributions that are important in theory or applications have been given specific names.

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🔗 Mass Noun

🔗 Linguistics

In linguistics, a mass noun, uncountable noun, non-count noun, uncount noun, or just uncountable, is a noun with the syntactic property that any quantity of it is treated as an undifferentiated unit, rather than as something with discrete elements. Non-count nouns are distinguished from count nouns.

Given that different languages have different grammatical features, the actual test for which nouns are mass nouns may vary between languages. In English, mass nouns are characterized by the impossibility of being directly modified by a numeral without specifying a unit of measurement and by the impossibility of being combined with an indefinite article (a or an). Thus, the mass noun "water" is quantified as "20 litres of water" while the count noun "chair" is quantified as "20 chairs". However, both mass and count nouns can be quantified in relative terms without unit specification (e.g., "so much water", "so many chairs").

Mass nouns have no concept of singular and plural, although in English they take singular verb forms. However, many mass nouns in English can be converted to count nouns, which can then be used in the plural to denote (for instance) more than one instance or variety of a certain sort of entity – for example, "Many cleaning agents today are technically not soaps [i.e. types of soap], but detergents," or "I drank about three beers [i.e. bottles or glasses of beer]".

Some nouns can be used indifferently as mass or count nouns, e.g., three cabbages or three heads of cabbage; three ropes or three lengths of rope. Some have different senses as mass and count nouns: paper is a mass noun as a material (three reams of paper, one sheet of paper), but a count noun as a unit of writing ("the students passed in their papers").

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🔗 Refal programming language

🔗 Computing

Refal ("[of] Recursive functions' algorithmic language") "is functional programming language oriented toward symbolic computations", including "string processing, language translation, [and] artificial intelligence". It is one of the oldest members of this family, first conceived of in 1966 as a theoretical tool, with the first implementation appearing in 1968. Refal was intended to combine mathematical simplicity with practicality for writing large and sophisticated programs.

One of the first functional programming languages to do so, and unlike Lisp of its time, Refal is based on pattern matching. Its pattern matching works in conjunction with term rewriting.

The basic data structure of Lisp and Prolog is a linear list built by cons operation in a sequential manner, thus with O(n) access to list's nth element. Refal's lists are built and scanned from both ends, with pattern matching working for nested lists as well as the top-level one. In effect, the basic data structure of Refal is a tree rather than a list. This gives freedom and convenience in creating data structures while using only mathematically simple control mechanisms of pattern matching and substitution.

Refal also includes a feature called the freezer to support efficient partial evaluation.

Refal can be applied to the processing and transformation of tree structures, similarly to XSLT.

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🔗 Alamut (Bartol Novel)

🔗 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.

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🔗 Gut–Brain Axis

🔗 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.

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🔗 Toast sandwich

🔗 Food and drink 🔗 United Kingdom

A toast sandwich is a sandwich made with two slices of bread in which the filling is a thin slice of toasted bread, which can be heavily buttered. An 1861 recipe says to add salt and pepper to taste.

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