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Biography
Berry L. Cannon
Berry Louis Cannon (March 22, 1935 – February 17, 1969)[1][2][3] was an United States of America aquanaut who served on the SEALAB II and III projects of the U.S. Navy. Cannon died of carbon dioxide poisoning while attempting to repair SEALAB III. It was later found that his diving rig's baralyme canister, which should have absorbed the carbon dioxide Cannon exhaled, was empty.[4] Born Marc
  • 1.3K
  • 28 Nov 2022
Topic Review
Robitussin
Cold medicines are a group of medications taken individually or in combination as a treatment for the symptoms of the common cold and similar conditions of the upper respiratory tract. The term encompasses a broad array of drugs, including analgesics, antihistamines and decongestants, among many others. It also includes drugs which are marketed as cough suppressants or antitussives, but their effectiveness in reducing cough symptoms is unclear or minimal. While they have been used by 10% of American children in any given week, they are not recommended in Canada or the United States in children six years or younger because of lack of evidence showing effect and concerns of harm. One version with codeine, guaifenesin, and pseudoephedrine was the 213th most commonly prescribed medication in 2017, in the United States, with more than two million prescriptions.
  • 1.1K
  • 25 Nov 2022
Topic Review
Aristotelian Physics
Aristotelian physics is the form of natural science described in the works of the Greek philosopher Aristotle (384–link BCE). In his work Physics, Aristotle intended to establish general principles of change that govern all natural bodies, both living and inanimate, celestial and terrestrial – including all motion (change with respect to place), quantitative change (change with respect to size or number), qualitative change, and substantial change ("coming to be" [coming into existence, 'generation'] or "passing away" [no longer existing, 'corruption']). To Aristotle, 'physics' was a broad field that included subjects that would now be called the philosophy of mind, sensory experience, memory, anatomy and biology. It constitutes the foundation of the thought underlying many of his works. Key concepts of Aristotelian physics include the structuring of the cosmos into concentric spheres, with the Earth at the centre and celestial spheres around it. The terrestrial sphere was made of four elements, namely earth, air, fire, and water, subject to change and decay. The celestial spheres were made of a fifth element, an unchangeable aether. Objects made of these elements have natural motions: those of earth and water tend to fall; those of air and fire, to rise. The speed of such motion depends on their weights and the density of the medium. Aristotle argued that a vacuum could not exist as speeds would become infinite. Aristotle described four causes or explanations of change as seen on earth: the material, formal, efficient, and final causes of things. As regards living things, Aristotle's biology relied on observation of natural kinds, both the basic kinds and the groups to which these belonged. He did not conduct experiments in the modern sense, but relied on amassing data, observational procedures such as dissection, and making hypotheses about relationships between measurable quantities such as body size and lifespan.
  • 3.5K
  • 25 Nov 2022
Topic Review
Caster
A caster (also known as castor according to some dictionaries) is a wheeled device typically mounted to a larger object that enables relatively easy rolling movement of the object. Casters are essentially housings, that include a wheel and a mounting to install the caster to objects (equipment, apparatus and more). Casters are found virtually everywhere, from office desk chairs to shipyards, and from hospital beds to automotive factories. They range in size from the very small furniture casters to massive industrial casters, and individual load capacities span 100 pounds (45 kg) or less to 100,000 pounds (45 t). Wheel materials include cast iron, plastic, rubber, polyurethane, polyolefin, nylon, thermoplastic rubber, forged steel, stainless steel, aluminum, and more.
  • 1.8K
  • 25 Nov 2022
Topic Review
Canopy
In biology, the canopy is the aboveground portion of a plant cropping or crop, formed by the collection of individual plant crowns. In forest ecology, canopy also refers to the upper layer or habitat zone, formed by mature tree crowns and including other biological organisms (epiphytes, lianas, arboreal animals, etc.). The communities that inhabit the canopy layer are thought to be involved in maintaining forest diversity, resilience, and functioning. Sometimes the term canopy is used to refer to the extent of the outer layer of leaves of an individual tree or group of trees. Shade trees normally have a dense canopy that blocks light from lower growing plants.
  • 3.4K
  • 25 Nov 2022
Topic Review
Elasticity
In physics and materials science, elasticity is the ability of a body to resist a distorting influence and to return to its original size and shape when that influence or force is removed. Solid objects will deform when adequate loads are applied to them; if the material is elastic, the object will return to its initial shape and size after removal. This is in contrast to plasticity, in which the object fails to do so and instead remains in its deformed state. The physical reasons for elastic behavior can be quite different for different materials. In metals, the atomic lattice changes size and shape when forces are applied (energy is added to the system). When forces are removed, the lattice goes back to the original lower energy state. For rubbers and other polymers, elasticity is caused by the stretching of polymer chains when forces are applied. Hooke's law states that the force required to deform elastic objects should be directly proportional to the distance of deformation, regardless of how large that distance becomes. This is known as perfect elasticity, in which a given object will return to its original shape no matter how strongly it is deformed. This is an ideal concept only; most materials which possess elasticity in practice remain purely elastic only up to very small deformations, after which plastic (permanent) deformation occurs. In engineering, the elasticity of a material is quantified by the elastic modulus such as the Young's modulus, bulk modulus or shear modulus which measure the amount of stress needed to achieve a unit of strain; a higher modulus indicates that the material is harder to deform. The SI unit of this modulus is the pascal (Pa). The material's elastic limit or yield strength is the maximum stress that can arise before the onset of plastic deformation. Its SI unit is also the pascal (Pa).
  • 2.9K
  • 06 May 2023
Topic Review
Degrees of Freedom (Physics and Chemistry)
In physics and chemistry, a degree of freedom is an independent physical parameter in the formal description of the state of a physical system. The set of all states of a system is known as the system's phase space, and the degrees of freedom of the system are the dimensions of the phase space. The location of a particle in three-dimensional space requires three position coordinates. Similarly, the direction and speed at which a particle moves can be described in terms of three velocity components, each in reference to the three dimensions of space. If the time evolution of the system is deterministic (where the state at one instant uniquely determines its past and future position and velocity as a function of time) such a system has six degrees of freedom. If the motion of the particle is constrained to a lower number of dimensions – for example, the particle must move along a wire or on a fixed surface – then the system has fewer than six degrees of freedom. On the other hand, a system with an extended object that can rotate or vibrate can have more than six degrees of freedom. In classical mechanics, the state of a point particle at any given time is often described with position and velocity coordinates in the Lagrangian formalism, or with position and momentum coordinates in the Hamiltonian formalism. In statistical mechanics, a degree of freedom is a single scalar number describing the microstate of a system. The specification of all microstates of a system is a point in the system's phase space. In the 3D ideal chain model in chemistry, two angles are necessary to describe the orientation of each monomer. It is often useful to specify quadratic degrees of freedom. These are degrees of freedom that contribute in a quadratic function to the energy of the system. Depending on what one is counting, there are several different ways that degrees of freedom can be defined, each with a different value.
  • 4.6K
  • 25 Nov 2022
Topic Review
Nestorianism
Nestorianism is a Christian theological doctrine that upholds several distinctive teachings in the fields of Christology and Mariology. It opposes the concept of hypostatic union and emphasizes a radical distinction between two natures (human and divine) of Jesus Christ. That Christological position is defined as radical dyophisitism. Nestorianism was named after Christian theologian Nestorius (386–450), Patriarch of Constantinople from 428 to 431, who was influenced by Christological teachings of Theodore of Mopsuestia at the School of Antioch. Nestorius' teachings brought him into conflict with other prominent church leaders, most notably Cyril of Alexandria, who criticized especially his rejection of the title Theotokos ("Mother of God") for Mary, the mother of Jesus. Nestorius and his teachings were eventually condemned as heretical at the Council of Ephesus in 431, and again at the Council of Chalcedon in 451, which led to the Nestorian Schism; churches supporting Nestorian teachings broke with the rest of the Christian Church. Following that, many of Nestorius's supporters relocated to the Sasanian Empire, where they affiliated with the local Christian community, known as the Church of the East. Over the next decades the Church of the East became increasingly Nestorian in doctrine, leading to it becoming known alternatively as the Nestorian Church.
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  • 25 Nov 2022
Topic Review
CRAFFT Screening Test
The CRAFFT Screening Test is a short clinical assessment tool designed to screen for substance-related risks and problems in adolescents. CRAFFT stands for the key words of the 6 items in the second section of the assessment - Car, Relax, Alone, Forget, Friends, Trouble. As of 2016, an updated version of the CRAFFT known as the “CRAFFT 2.0” has been released. The older version of the questionnaire contains 9 items in total, answered in a "yes" or "no" format. The first three items (Part A) evaluate alcohol and drug use over the past year and the other six (Part B) ask about situations in which the respondent used drugs or alcohol and any consequences of the usage. The CRAFFT 2.0 screening tool begins with past-12-month frequency items (Part A), rather than the previous “yes/no” question for any use over the past year and the other six (Part B) ask about situations in which the respondent used drugs or alcohol and any consequences of usage. The CRAFFT can function as a self-report questionnaire or an interview to be administered by a clinician. Both employ a skip pattern: those whose Part A score is "0" (no use) answer the Car question only of Part B, while those who report any use in Part A also answer Part B's five CRAFFT questions. Each "yes" answer is scored as "1" point and a CRAFFT total score of two or higher identifies "high risk" for a substance use disorder and warrants further assessment.
  • 1.2K
  • 25 Nov 2022
Topic Review
Grandiosity
In the field of psychology, the term grandiosity refers to an unrealistic sense of superiority, characterized by a sustained view of one's self as better than others, which is expressed by disdainfully criticising them, overinflating one's own capability and belittling them as inferior; and refers to a sense of personal uniqueness, the belief that few other people have anything in common with oneself, and that one can only be understood by a few, very special people. The personality trait of grandiosity is principally associated with narcissistic personality disorder (NPD), but also is a feature in the occurrence and expression of antisocial personality disorder, and the manic and hypomanic episodes of bipolar disorder.
  • 3.3K
  • 25 Nov 2022
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