Subject:
All Disciplines Arts & Humanities Biology & Life Sciences Business & Economics Chemistry & Materials Science Computer Science & Mathematics Engineering Environmental & Earth Sciences Medicine & Pharmacology Physical Sciences Public Health & Healthcare Social Sciences
Sort:
Hottest Latest Alphabetical (A-Z) Alphabetical (Z-A)
Type:
All Topic Review Biography
Topic Review
Participatory Forest Management
Participatory forest management has been considered as a practical and effective strategy for sustainable forest management, especially in situations where land tenure is not securely settled. For effective restoration projects, local communities, as the cornerstone of participatory management, should be provided with incentives to facilitate their participation and active role. We postulate that participation in mangrove restoration projects can not only provide financial rewards but also yield intangible benefits for communities, i.e., social capital upgraded. Our study with the case of coastal mangrove restoration in the Philippines concluded that local people’s participation is a viable option for natural resource management that can create benefits and favorable conditions to communities. 
  • 12.6K
  • 27 Oct 2020
Topic Review
Multiverse (Religion)
The concept of a multiverse is explored in various religious cosmologies that propose that the totality of existence comprises multiple or infinitely many universes, including our own. Usually, such beliefs include a creation myth, a history, a worldview and a prediction of the eventual fate or destiny of the world. The worldview discusses the current organizational form of our universe and may contain references to other supernatural world or worlds. These references have aided several esoteric practices, including contacts with spirit worlds, and activities concerning personal or inner spiritual development. Many of these worlds include an afterlife existence, which may be very different from existence in the physical plane or the world of the living; common afterlife realms include heaven, hell, and realm of the dead. Eschatological scenarios may include a new, different world after the end time of the current world. For example, Hindu cosmology includes the idea of an infinite cycle of births and deaths and an infinite number of universes with each cycle lasting 8.64 billion years. The cosmological ideas in various religious traditions have clearly evolved in time due to the introduction of new concepts and the exchange of ideas with other cultures. Nevertheless, perennial philosophers believe that these traditions all share a single supernatural truth or origin.
  • 12.6K
  • 21 Nov 2022
Topic Review
Cement Production in Nigeria
Cement is the most common and extensively used adhesive in the construction industry. It is employed on highways, houses, embankments, bridges, commercial establishments, and flyovers. In recent years, the Nigerian cement industry has grown from import dependency to an export-thriving epicentre within Africa. The country possesses the largest cement industry within West Africa, with at least 12 registered companies amounting to a merged cement capacity of 58.9 Mt/yr. Dangote Cement is the largest cement producer in Nigeria and West Africa, manufacturing a combined share of more than 28.5 Mt/yr of cement capacity. Also, LafargeHolcim (through its subsidiary AshakaCem & Lafarge WAPCO) and BUA Group boost 18.9 Mt/yr and 11.5 Mt/yr of integrated cement capacity, respectively.
  • 12.6K
  • 16 Sep 2021
Topic Review
Timoshenko-Ehrenfest Beam Theory
The Timoshenko-Ehrenfest beam theory was developed by Stephen Timoshenko and Paul Ehrenfest early in the 20th century. The model takes into account shear deformation and rotational bending effects, making it suitable for describing the behaviour of thick beams, sandwich composite beams, or beams subject to high-frequency excitation when the wavelength approaches the thickness of the beam. The resulting equation is of 4th order but, unlike Euler–Bernoulli beam theory, there is also a second-order partial derivative present. Physically, taking into account the added mechanisms of deformation effectively lowers the stiffness of the beam, while the result is a larger deflection under a static load and lower predicted eigenfrequencies for a given set of boundary conditions. The latter effect is more noticeable for higher frequencies as the wavelength becomes shorter (in principle comparable to the height of the beam or shorter), and thus the distance between opposing shear forces decreases. Rotary inertia effect was introduced by Bresse and Rayleigh. If the shear modulus of the beam material approaches infinity—and thus the beam becomes rigid in shear—and if rotational inertia effects are neglected, Timoshenko beam theory converges towards ordinary beam theory.
  • 12.6K
  • 20 Oct 2022
Topic Review
Decay Theory
The Decay theory is a theory that proposes that memory fades due to the mere passage of time. Information is therefore less available for later retrieval as time passes and memory, as well as memory strength, wears away. When an individual learns something new, a neurochemical "memory trace" is created. However, over time this trace slowly disintegrates. Actively rehearsing information is believed to be a major factor counteracting this temporal decline. It is widely believed that neurons die off gradually as we age, yet some older memories can be stronger than most recent memories. Thus, decay theory mostly affects the short-term memory system, meaning that older memories (in long-term memory) are often more resistant to shocks or physical attacks on the brain. It is also thought that the passage of time alone cannot cause forgetting, and that decay theory must also take into account some processes that occur as more time passes.
  • 12.5K
  • 31 Oct 2022
Topic Review
Environmental Risk Factors
Environmental health is a growing area of knowledge, continually increasing and updating the body of evidence linking the environment to human health.
  • 12.5K
  • 03 Dec 2022
Topic Review
Pharmakon
Pharmakon, in philosophy and critical theory, is a composite of three meanings: remedy, poison, and scapegoat. The first and second senses refer to the everyday meaning of pharmacology (and to its sub-field, toxicology), deriving from the Greek source term φάρμακον (phármakon), denoting any drug, while the third sense refers to the pharmakos ritual of human sacrifice. A further sub-sense of pharmakon as remedy which is of interest to some current authors is given by the Liddell-Scott-Jones Greek–English Lexicon as "a means of producing something". In recent philosophical work, the term centers on Jacques Derrida's "Plato's Pharmacy", and the notion that writing is a pharmakon. Whereas a straightforward view on Plato's treatment of writing (in Phaedrus) suggests that writing is to be rejected as strictly poisonous to the ability to think for oneself in dialogue with others (i.e. to anamnesis), Bernard Stiegler argues that "the hypomnesic appears as that which constitutes the condition of the anamnesic"—in other words, externalised time-bound communication is necessary for original creative thought, in part because it is the primordial support of culture. Michael Rinella has written a book-length review of the pharmakon within a historical context, with an emphasis on the relationship between pharmakoi in the standard drug sense and the philosophical understanding of the term. Adrian Mróz, a Polish-American philosopher and musician, analyses its application to art and argues that pharmakon is any physical, mental, or behavioral object which can cut (techne). In other words, pharmaka are agential and responsible for changes in consciousness.
  • 12.5K
  • 07 Nov 2022
Topic Review
Alpha (Ethology)
In studies of social animals, the highest ranking individual of a dominance hierarchy is sometimes designated as the alpha. Males, females, or both, can be alphas, depending on the species. Where one male and one female fulfill this role together, they are sometimes referred to as the alpha pair. Other animals in the same social group may exhibit deference or other species-specific subordinate behavior towards the alpha or alphas. Alpha animals usually gain preferential access to food and other desirable items or activities, though the extent of this varies widely between species. Male or female alphas may gain preferential access to sex or mates; in some species, only alphas or an alpha pair reproduce. Alphas may achieve their status by superior physical strength and aggression, or through social efforts and building alliances within the group, or more often, simply by breeding and being the parent of all in their pack. The individual with alpha status sometimes changes, often through a fight between the dominant and a subordinate animal. These fights are often to the death, depending on the animal.
  • 12.5K
  • 04 Nov 2022
Topic Review
Mercedes-Benz CLS-Class (W219)
The C219 Mercedes-Benz CLS-Class is the first generation of the CLS-Class range of four-door coupe features a fastback body style by Mercedes-Benz, and was produced between 2004 and 2010. The CLS-Class has only four seats and is marketed by Mercedes as a four-door coupé. For this reason, in Germany and in whole Europe the model code name is C219 while in US the CLS is more commonly named as W219 model. It was the first model globally to introduce this four-door coupe style and VW followed with the Volkswagen CC model in 2008. The car is less practical than the W211 E-Class that it is based on, with less legroom, headroom, and boot space. The CLS-Class is priced above the E-Class, but below the S-Class in the Mercedes model range. It was replaced by the Mercedes-Benz CLS-Class (W218) in 2011.
  • 12.4K
  • 04 Nov 2022
Topic Review
Pi-Stacking
In chemistry, pi stacking (also called π–π stacking) refers to the presumptive attractive, noncovalent interactions (orbital overlap) between the pi bonds of aromatic rings. However this is a misleading description of the phenomena since direct stacking of aromatic rings (the "sandwich interaction") is electrostatically repulsive. What is more commonly observed (see figure to the right) is either a staggered stacking (parallel displaced) or pi-teeing (perpendicular T-shaped) interaction both of which are electrostatic attractive For example, the most commonly observed interactions between aromatic rings of amino acid residues in proteins is a stagered stacked followed by a perpendular orientation. Sandwiched orientations are relatively rare. Pi stacking is repulsive as it places carbon atoms with partial negative charges from one ring on top of other partial negatively charged carbon atoms from the second ring and hydrogen atoms with partial postive charges on top of other hydrogen atoms that likewise carry partial positive charges. In staggered stacking, one of the two aromatic rings is offset sideways so that the carbon atoms with partial negative charge in the first ring are placed above hydrogen atoms with partial positive charge in the second ring so that the electrostatic interactions become attractive. Likewise, pi-teeing interactions in which the two rings are oriented perpendicultar to either other is electrostatically attractive as it places partial postively charged hydrogen atoms in close proximity to partially negatively charged carbon atoms. An alternative explanation for the preference for staggered stacking is due to the balance between van der Waals interactions (attractive dispersion plus Pauli repulsion). These staggered stacking and π-teeing interactions between aromatic rings are important in nucleobase stacking within DNA and RNA molecules, protein folding, template-directed synthesis, materials science, and molecular recognition. Despite the wide use of term pi stacking in the scientific literature, there is no theoretical justification for its use.
  • 12.4K
  • 12 Oct 2022
  • Page
  • of
  • 5352
Featured Entry Collections
>>

Featured Books

>>
Encyclopedia of Social Sciences
Encyclopedia of COVID-19
Encyclopedia of Fungi
Encyclopedia of Digital Society, Industry 5.0 and Smart City
Video Production Service
Feedback