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🔗 Vaccine-Preventable Diseases

🔗 Medicine

A vaccine-preventable disease is an infectious disease for which an effective preventive vaccine exists. If a person acquires a vaccine-preventable disease and dies from it, the death is considered a vaccine-preventable death.

The most common and serious vaccine-preventable diseases tracked by the World Health Organization (WHO) are: diphtheria, Haemophilus influenzae serotype b infection, hepatitis B, measles, meningitis, mumps, pertussis, poliomyelitis, rubella, tetanus, tuberculosis, and yellow fever. The WHO reports licensed vaccines being available to prevent, or contribute to the prevention and control of, 27 vaccine-preventable infections.

🔗 The knowledge argument

🔗 Philosophy 🔗 Philosophy/Logic 🔗 Philosophy/Philosophy of mind

The knowledge argument (also known as Mary's room or Mary the super-scientist) is a philosophical thought experiment proposed by Frank Jackson in his article "Epiphenomenal Qualia" (1982) and extended in "What Mary Didn't Know" (1986). The experiment is intended to argue against physicalism—the view that the universe, including all that is mental, is entirely physical. The debate that emerged following its publication became the subject of an edited volume—There's Something About Mary (2004)—which includes replies from such philosophers as Daniel Dennett, David Lewis, and Paul Churchland.

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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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🔗 List of multiple discoveries

🔗 Lists 🔗 History of Science 🔗 Science

Historians and sociologists have remarked the occurrence, in science, of "multiple independent discovery". Robert K. Merton defined such "multiples" as instances in which similar discoveries are made by scientists working independently of each other. "Sometimes," writes Merton, "the discoveries are simultaneous or almost so; sometimes a scientist will make a new discovery which, unknown to him, somebody else has made years before."

Commonly cited examples of multiple independent discovery are the 17th-century independent formulation of calculus by Isaac Newton, Gottfried Wilhelm Leibniz and others, described by A. Rupert Hall; the 18th-century discovery of oxygen by Carl Wilhelm Scheele, Joseph Priestley, Antoine Lavoisier and others; and the theory of the evolution of species, independently advanced in the 19th century by Charles Darwin and Alfred Russel Wallace.

Multiple independent discovery, however, is not limited to such famous historic instances. Merton believed that it is multiple discoveries, rather than unique ones, that represent the common pattern in science.

Merton contrasted a "multiple" with a "singleton"—a discovery that has been made uniquely by a single scientist or group of scientists working together.

A distinction is drawn between a discovery and an invention, as discussed for example by Bolesław Prus. However, discoveries and inventions are inextricably related, in that discoveries lead to inventions, and inventions facilitate discoveries; and since the same phenomenon of multiplicity occurs in relation to both discoveries and inventions, this article lists both multiple discoveries and multiple inventions.

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🔗 Whois++

The WHOIS++ protocol is a distributed directory system, originally designed to provide a "white pages" search mechanism to find humans, but which could actually be used for arbitrary information retrieval tasks. It was developed in the early 1990s by BUNYIP Information Systems and is documented in the IETF.

WHOIS++ was devised as an extension to the pre-existing WHOIS system. WHOIS was an early networked directory service, originally maintained by SRI International for the Defense Data Network. The WHOIS protocol is still widely used to allow domain ownership records in the Internet to be easily queried.

WHOIS++ attempted to address some of the short comings in the original WHOIS protocol that had become apparent over the years. It supported multiple languages and character sets to help with I18N issues, had a more advanced query syntax, and the ability to generate "forward knowledge" in the form of 'centroid' data structures that could be used to route queries from one server to another. The protocol was designed to be backward compatible with the older WHOIS standard, so that WHOIS++ clients could still extract meaningful information from the already deployed WHOIS servers.

Whilst WHOIS++ as a white pages directory service never really took off compared to competitors such as X.500, it did gain a notable amount of use in the United Kingdom as the underlying search and retrieval protocol of a number of subject based gateways funded as part of the Jisc Electronic library programme. This was achieved using software called ROADS that provided WHOIS++ base and index servers and CGI based web interfaces to WHOIS++ clients. The use of centroids to provide forward knowledge and query routing allowed a subject gateway to not only provide resources to academic users from their own database but also point them at other JISC funded subject gateways that might have useful information.

The WHOIS++ protocol is now designated by the IETF as a historic protocol and is no longer deployed in new systems or developed.

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🔗 Corsi–Rosenthal Box

🔗 Technology 🔗 Medicine

The Corsi–Rosenthal Box, also called a Corsi–Rosenthal Cube or a Comparetto Cube, is a design for a do-it-yourself air purifier that can be built comparatively inexpensively. It was designed during the COVID-19 pandemic with the goal of reducing the levels of airborne viral particles in indoor settings.

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🔗 Cantor function, a.k.a. devil's staircase: increasing function with 0 derivative

🔗 Mathematics 🔗 Systems 🔗 Systems/Chaos theory

In mathematics, the Cantor function is an example of a function that is continuous, but not absolutely continuous. It is a notorious counterexample in analysis, because it challenges naive intuitions about continuity, derivative, and measure. Though it is continuous everywhere and has zero derivative almost everywhere, its value still goes from 0 to 1 as its argument reaches from 0 to 1. Thus, in one sense the function seems very much like a constant one which cannot grow, and in another, it does indeed monotonically grow, by construction.

It is also referred to as the Cantor ternary function, the Lebesgue function, Lebesgue's singular function, the Cantor–Vitali function, the Devil's staircase, the Cantor staircase function, and the Cantor–Lebesgue function. Georg Cantor (1884) introduced the Cantor function and mentioned that Scheeffer pointed out that it was a counterexample to an extension of the fundamental theorem of calculus claimed by Harnack. The Cantor function was discussed and popularized by Scheeffer (1884), Lebesgue (1904) and Vitali (1905).

🔗 Perverse Incentive

🔗 History 🔗 Economics 🔗 Philosophy 🔗 Business 🔗 Philosophy/Ethics

A perverse incentive is an incentive that has an unintended and undesirable result that is contrary to the intentions of its designers. The cobra effect is the most direct kind of perverse incentive, typically because the incentive unintentionally rewards people for making the issue worse. The term is used to illustrate how incorrect stimulation in economics and politics can cause unintended consequences.

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🔗 Seed7 programming language

🔗 Computing

Seed7 is an extensible general-purpose programming language designed by Thomas Mertes. It is syntactically similar to Pascal and Ada. Along with many other features, it provides an extension mechanism. Seed7 supports introducing new syntax elements and their semantics into the language, and allows new language constructs to be defined and written in Seed7. For example, programmers can introduce syntax and semantics of new statements and user defined operator symbols. The implementation of Seed7 differs significantly from that of languages with hard-coded syntax and semantics.

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🔗 Foetry.com

🔗 Internet 🔗 Computing 🔗 Literature

Foetry.com, sometimes referred to as just Foetry, was a website that attempted to identify fraudulent and unethical practices in poetry contests. It was active from April 1, 2004 until May 18, 2007.

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