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Topic Review

Kübler-Ross Model

The Kübler-Ross model, or the Five Stages of Grief, postulates a series of emotions experienced by terminally ill patients prior to death, or people who have lost a loved one, wherein the five stages are: denial, anger, bargaining, depression, and acceptance. Although commonly referenced in popular media, the existence of these stages has not been empirically demonstrated and the model is not considered helpful in explaining the grieving process. It is considered to be of historical value but outdated in scientific terms and in clinical practice. The model was first introduced by Swiss-American psychiatrist Elisabeth Kübler-Ross in her 1969 book On Death and Dying, and was inspired by her work with terminally ill patients. Motivated by the lack of instruction in medical schools on the subject of death and dying, Kübler-Ross examined death and those faced with it at the University of Chicago's medical school. Kübler-Ross's project evolved into a series of seminars which, along with patient interviews and previous research, became the foundation for her book. Although Kübler-Ross is commonly credited with creating stage models, earlier bereavement theorists and clinicians such as Erich Lindemann, Collin Murray Parkes, and John Bowlby used similar models of stages of phases as early as the 1940s. Later in her life, Kübler-Ross noted that the stages are not a linear and predictable progression and that she regretted writing them in a way that was misunderstood. "Kübler-Ross originally saw these stages as reflecting how people cope with illness and dying," observed grief researcher Kenneth J. Doka, "not as reflections of how people grieve."

5.9K
03 Nov 2022

Topic Review

The term ‘rock art’ defines non-utilitarian humanly made markings on natural rock surfaces, caused either by an additive (pictograms, made by the application of material) or a reductive process (petroglyphs, made by the removal of rock material). The former include rock paintings, pigment drawings, stencils, and beeswax figures; the latter term covers engravings, percussion petroglyphs, and finger flutings. Rock art occurs in nearly all countries. Its uneven distribution is attributable to differences in cultural conventions as well as a taphonomic attribute, i.e. a result of preservation bias. Prehistoric rock art represents by far the largest body of evidence we possess of humanity’s cultural, cognitive, and artistic beginnings. Through its relative permanence, it has profoundly influenced the beliefs and cultural conventions of subsequent societies up to the present. It is, therefore, an integral part of humanity's collective memory and the most significant surviving witness of our cultural evolution.

5.9K
07 Apr 2021

Topic Review

Tether (Cryptocurrency)

Tether (often referred to by one of its currency codes, USD₮), is an asset-backed cryptocurrency stablecoin. It was launched by the company Tether Limited Inc. in 2014. Tether Limited is owned by the Hong Kong-based company iFinex Inc., which also owns the Bitfinex cryptocurrency exchange. As of July 2022, Tether Limited has minted the USDT stablecoin on ten protocols and blockchains. Tether is described as a stablecoin because it was originally designed to be valued at USD $1.00, with Tether Limited maintaining USD $1.00 of asset reserves for each USDT issued.

5.9K
16 Nov 2022

Topic Review

Low Intensity Conflict

A low-intensity conflict (LIC) is a military conflict, usually localised, between two or more state or non-state groups which is below the intensity of conventional war. It involves the state's use of military forces applied selectively and with restraint to enforce compliance with its policies or objectives. The term can be used to describe conflicts where at least one or both of the opposing parties operate along such lines.

5.9K
27 Sep 2022

Topic Review

Classification of the Approved EGFR-TKIs

Targeting EGFR with small-molecule inhibitors is a valid strategy in cancer therapy. Since the approval of the first EGFR-TKI in 2003, a huge number of EGFR inhibitors were reported. Classification of these inhibitors could help the researchers to understand their structure-activity relationship. Herein, we introduce different types of classifications of the EGFR-TKIs, which received global approval for clinical use. In the following, the EGFR-targeting drugs are classified based on their chemistry, clinical use, target kinases, and the type of inhibition/interaction with EGFR.

5.9K
25 Nov 2021

Topic Review

In mathematics, the sine is a trigonometric function of an angle. The sine of an acute angle is defined in the context of a right triangle: for the specified angle, it is the ratio of the length of the side that is opposite that angle, to the length of the longest side of the triangle (the hypotenuse). For an angle [math]\displaystyle{ x }[/math], the sine function is denoted simply as [math]\displaystyle{ \sin x }[/math]. More generally, the definition of sine (and other trigonometric functions) can be extended to any real value in terms of the length of a certain line segment in a unit circle. More modern definitions express the sine as an infinite series, or as the solution of certain differential equations, allowing their extension to arbitrary positive and negative values and even to complex numbers. The sine function is commonly used to model periodic phenomena such as sound and light waves, the position and velocity of harmonic oscillators, sunlight intensity and day length, and average temperature variations throughout the year. The function sine can be traced to the jyā and koṭi-jyā functions used in Gupta period Indian astronomy (Aryabhatiya, Surya Siddhanta), via translation from Sanskrit to Arabic, and then from Arabic to Latin. The word "sine" (Latin "sinus") comes from a Latin mistranslation by Robert of Chester of the Arabic jiba, which is a transliteration of the Sanskrit word for half the chord, jya-ardha.

5.9K
11 Oct 2022

Topic Review

Comparison between Traditional (Passive) Learning and Active Learning

Active learning has been increasingly important in tertiary education due to its powerfully favourable impact on students’ learning attitudes and efficacy. The way that a classroom is set up has a direct impact on how well students learn and how well teachers teach. The continuous evaluation of students’ learning performance is essential for guiding future classroom renovations and creating a cutting-edge learning environment for both students and teachers.

5.9K
20 Jun 2023

Topic Review

Broadcasting is the distribution of audio or video content to a dispersed audience via any electronic mass communications medium, but typically one using the electromagnetic spectrum (radio waves), in a one-to-many model. Broadcasting began with AM radio, which came into popular use around 1920 with the spread of vacuum tube radio transmitters and receivers. Before this, all forms of electronic communication (early radio, telephone, and telegraph) were one-to-one, with the message intended for a single recipient. The term broadcasting evolved from its use as the agricultural method of sowing seeds in a field by casting them broadly about. It was later adopted for describing the widespread distribution of information by printed materials or by telegraph. Examples applying it to "one-to-many" radio transmissions of an individual station to multiple listeners appeared as early as 1898. Over the air broadcasting is usually associated with radio and television, though more recently, both radio and television transmissions have begun to be distributed by cable (cable television). The receiving parties may include the general public or a relatively small subset; the point is that anyone with the appropriate receiving technology and equipment (e.g., a radio or television set) can receive the signal. The field of broadcasting includes both government-managed services such as public radio, community radio and public television, and private commercial radio and commercial television. The U.S. Code of Federal Regulations, title 47, part 97 defines "broadcasting" as "transmissions intended for reception by the general public, either direct or relayed". Private or two-way telecommunications transmissions do not qualify under this definition. For example, amateur ("ham") and citizens band (CB) radio operators are not allowed to broadcast. As defined, "transmitting" and "broadcasting" are not the same. Transmission of radio and television programs from a radio or television station to home receivers by radio waves is referred to as "over the air" (OTA) or terrestrial broadcasting and in most countries requires a broadcasting license. Transmissions using a wire or cable, like cable television (which also retransmits OTA stations with their consent), are also considered broadcasts but do not necessarily require a license (though in some countries, a license is required). In the 2000s, transmissions of television and radio programs via streaming digital technology have increasingly been referred to as broadcasting as well.

5.9K
24 Nov 2022

Topic Review

Hamilton Family

The Hamiltons of the United States are a family of Scottish origin, whose most prominent member was Alexander Hamilton (1755/1757–1804), one of the Founding Fathers of the United States. Their ancestors and relations in Scotland included the Lairds of Kerelaw Castle in Stevenston, North Ayrshire, of the Cambuskeith branch of Clan Hamilton.

5.9K
14 Oct 2022

Topic Review

Properties and Synthesis of Photocatalysts

The photocatalysts must be characterized by the ability to absorb radiation from a wide spectral range of light, the appropriate position of the semiconductor energy bands in relation to the redox reaction potentials, and the long diffusion path of charge carriers, besides the thermodynamic, electrochemical, and photoelectrochemical stabilities.

5.9K
30 Dec 2022

Topic Review

Silappatikāram (Tamil: சிலப்பதிகாரம், IPA: ʧiləppət̪ikɑːrəm, lit. "the Tale of an Anklet"), also referred to as Silappathikaram or Silappatikaram, is the earliest Hindu-Jain Tamil semi-legendary epic. It is a poem of 5,730 lines in almost entirely akaval (aciriyam) meter. The epic is a tragic love story of an ordinary couple, Kannaki and her husband Kovalan. The Silappathikaram has more ancient roots in the Tamil bardic tradition, as Kannaki and other characters of the story are mentioned or alluded to in the Sangam literature such as in the Naṟṟiṇai and later texts such as the Kovalam Katai. It is attributed to a prince-turned-monk Iḷaṅkõ Aṭikaḷ, and was probably composed in the 5th or 6th century CE. The Silappatikaram is set in a flourishing seaport city of the early Chola kingdom. Kannaki and Kovalan are a newly married couple, in love, and living in bliss. Over time, Kovalan meets Matavi (Madhavi) – a courtesan. He falls for her, leaves Kannaki and moves in with Matavi. He spends lavishly on her. Kannaki is heartbroken, but as the chaste woman, she waits despite her husband's unfaithfulness. During the festival for Indra, the rain god, there is a singing competition. Kovalan sings a poem about a woman who hurt her lover. Matavi then sings a song about a man who betrayed his lover. Each interprets the song as a message to the other. Kovalan feels Matavi is unfaithful to him, and leaves her. Kannaki is still waiting for him. She takes him back. Kannagi and Kovalan leave the city and travel to Madurai of the Pandya kingdom. Kovalan is penniless and destitute. He confesses his mistakes to Kannagi. She forgives him and tells him the pain his unfaithfulness gave her. Then she encourages her husband to rebuild their life together and gives him one of her jeweled anklets to sell to raise starting capital. Kovalan sells it to a merchant, but the merchant falsely frames him as having stolen the anklet from the queen. The king arrests Kovalan and then executes him, without the due checks and processes of justice. When Kovalan does not return home, Kannagi goes searching for him. She learns what has happened. She protests the injustice and then proves Kovalan's innocence by throwing in the court the other jeweled anklet of the pair. The king accepts his mistake. Kannagi curses the king and curses the people of Madurai, tearing off her breast and throwing it at the gathered public. The king dies. The society that had made her suffer, suffers in retribution as the city of Madurai is burnt to the ground because of her curse. In the third section of the epic, gods and goddesses meet Kannagi and she goes to heaven with god Indra. The royal family of the Chera kingdom learns about her, resolves to build a temple with Kannagi as the featured goddess. They go to the Himalayas, bring a stone, carve her image, call her goddess Pattini, dedicate a temple, order daily prayers, and perform a royal sacrifice. The Silappathikaram is an ancient literary Jain masterpiece. It is to the Tamil culture what the Iliad is to the Greek culture, states R. Parthasarathy. It blends the themes, mythologies and theological values found in the Jain, Buddhist and Hindu religious traditions. It is a Tamil story of love and rejection, happiness and pain, good and evil like all classic epics of the world. Yet unlike other epics that deal with kings and armies caught up with universal questions and existential wars, the Silappathikaram is an epic about an ordinary couple caught up with universal questions and internal, emotional war. The Silappathikaram legend has been a part of the Tamil oral tradition. The palm-leaf manuscripts of the original epic poem, along with those of the Sangam literature, were rediscovered in monasteries in the second half of the 19th century by UV Swaminatha Aiyar – a pandit and Tamil scholar. After being preserved and copied in temples and monasteries in the form of palm-leaf manuscripts, Aiyar published its first partial edition on paper in 1872, the full edition in 1892. Since then the epic poem has been translated into many languages including English.

5.9K
08 Oct 2022

Topic Review

Thermodynamic Dissipation Theory of Life

The Thermodynamic Dissipation Theory of the Origin and Evolution of Life argues that the escence of the origin of life was the microscopic dissipative structuring under UVC light of organic pigments (now known as the fundamental molecules of life - those common to all three domains) and their proliferation over the entire Earth surface, driven by the thermodynamic imperative of dissipating this part of the Archean solar spectrum into heat. With time, dissipative structuring led to ever more complex biosynthetic pathways for creating pigments and their support structures (and processes) which could dissipate not only the UVC region but also other UV regions and the visible wavelengths, until today reaching the "red edge" (at approximately 700 nm). The heat of dissipation of photons absorbed on organic pigments in water then catalyzes a host of coupled secondary dissipative processes such as; the water cycle, ocean and wind currents, hurricanes, etc. pushing the limit for dissipation of the incident light even further towards the infrared. The thermodynamic dissipation theory thus assgins an explicit thermodynamic function to life; the dissipative structuring, proliferation, and evolution of molecular pigments and their complexes from common precursor carbon based molecules under the impressed short wavelength solar photon potential to perform the explicit thermodynamic function of dissipating this light into long wavelength infrared light (heat). In a general sense, the origin of life is no different than the origin of other dissipative structuring processes like hurricanes and the water cycle, except that these latter processes deal with structuring involving hydrogen bonding while life deals with structuring involving covalent bonding. The external photon potential supplied continuously by the environment (our Sun), and its dissipation into heat by the assembly of dissipative structures, are, therefore, both integral components necessary for understanding life. Difficult problems related to the origin of life, such as enzyme-less replication of RNA and DNA, homochirality of the fundamental molecules, and the origin of amino acid -codon assignments (information encoding in RNA and DNA), also find simple explanations within this same dissipative thermodynamic framework once the existence of a relation between primordial RNA and DNA replication and UV-C photon dissipation is established.

5.9K
04 Feb 2021

Topic Review

Methods for Recycling Heterogenous Catalysts

The rapid separation and efficient recycling of catalysts after a catalytic reaction are considered important requirements along with the high catalytic performances. In this view, although heterogeneous catalysis is generally less efficient if compared to the homogeneous type, it is generally preferred since it benefits from the easy recovery of the catalyst. Recycling of heterogeneous catalysts using traditional methods of separation such as extraction, filtration, vacuum distillation, or centrifugation is tedious and time-consuming. They are uneconomic processes and, hence, they cannot be carried out in the industrial scale.

5.9K
23 Jun 2021

Topic Review

Virtual Power Plants (VPPs)

A virtual power plants (VPPs) is an alternative for the management of Distributed Energy Resources (DER) in the electricity system, which operates based on the concept of the “virtual cloud”. Its specific role is visibility and the technical and commercial integration of DERs in the power system. It is capable of grouping and managing the technical potential of different DERs (microgrids included), regardless of the voltage level at which they are interconnected with the network and without a geographical restriction between the elements. It is modeled as a single virtual element associated with the distribution network to guarantee a safe, efficient, cooperative and complementary operation between its elements, both in commercial and technical aspects. The VPP has the capacity to participate in the electricity market as a manager of controllable loads and as a provider of energy, power reserve and ancillary services.

5.9K
18 Feb 2022

Topic Review

The term “smart window” was coined by Granqvist in 1985. From the early 1980s, smart glazing has been a rapidly developing innovative technology that is aimed to help manage energy transfer through the building’s envelope, evading unnecessary “cooling and heating of indoor air”. The use of smart glass, which helps to regulate the amount of light (and heat) entering a building, is one of the possible ways to reduce energy consumption in buildings while maintaining an appropriate level of comfort for users. Smart glass greatly influences the building envelope performance in (i) thermal management, (ii) daylight harvesting and regulation, (iii) reduction of glare, (iv) maintenance of views, (v) power capture, and finally (vi) activating the envelope as an information display. Some technologies are currently available on the market, although—in light of the many shortcomings of the existing solutions—smart glass is the subject of ongoing “intensive research aimed at improving the technology and its widespread use”.

5.9K
23 Sep 2021

Topic Review

In software development, Make is a build automation tool that automatically builds executable programs and libraries from source code by reading files called Makefiles which specify how to derive the target program. Though integrated development environments and language-specific compiler features can also be used to manage a build process, Make remains widely used, especially in Unix and Unix-like operating systems. Besides building programs, Make can be used to manage any project where some files must be updated automatically from others whenever the others change.

5.9K
28 Sep 2022

Topic Review

Poisonous Plants of the Indian Himalaya

Indian Himalayan region (IHR) supports a wide diversity of plants and most of them are known for their medicinal value. Humankind has been using medicinal plants since the inception of civilization. Various types of bioactive compounds are found in plants, which are directly and indirectly beneficial for plants as well as humans. These bioactive compounds are highly useful and being used as a strong source of medicines, pharmaceuticals, agrochemicals, food additives, fragrances, and flavoring agents. Apart from this, several plant species contain some toxic compounds that affect the health of many forms of life as well as cause their death. These plants are known as poisonous plants, because of their toxicity to both humans and animals.

5.9K
27 Jul 2022

Topic Review

Gas Turbines with Water Injection and Full Evaporation

The concept behind humidifying gas turbines is that increasing the amount of water/steam injected into the turbine increases the amount of mass it moves. This results in a rise in the specific power output because the effort exerted by the compressor remains the same, and it takes far less effort to raise the pressure of a liquid than it does of a gas. The efficiency of the cycle may be improved by recovering the energy contained in the gas turbine’s exhaust and either preheating the injection water, making injection steam, or the recuperator’s preheating of the combustion oxidizer. The introduction of water prior to the combustor of a recuperated gas turbine lowers the compressed air’s temperature at the input of the recuperator. This results in an increase in the rate at which energy is recovered from the exhaust gas.

5.9K
27 Dec 2022

Topic Review

Landsat 8 and Landsat 9

With the launch of Landsat 9 in September 2021, an optimal opportunity for in-flight cross-calibration occurred when Landsat 9 flew underneath Landsat 8 while being moved into its final orbit. Since the two instruments host nearly identical imaging systems, the underfly event offered ideal cross-calibration conditions. Using the underfly imagery collected by the instruments to estimate cross-calibration parameters for Landsat 9 for a calibration update scheduled at the end of the on-orbit initial verification (OIV) period was studied. Three types of uncertainty were considered: geometric, spectral, and angular (bidirectional reflectance distribution function—BRDF). Differences caused by geometric uncertainty were found to be negligible for this application.

5.9K
01 Jun 2022

Topic Review

Solar Reflectance Measurement

The relative amount of solar radiation reflected by a surface is specified as solar reflectance, or albedo. The latter term sometimes refers only to visible sunlight (Vis), while the former generally refers to the entire spectrum of solar radiation, including near-infrared (NIR) and ultraviolet (UV) radiation. However, the scientific and technical communities consider albedo and solar reflectance synonymous, with both referring to the entire solar spectrum. Solar reflectance is usually expressed as a value between zero, for a surface absorbing all incoming radiation, and one, for a perfect reflector—or as a percentage between 0 and 100%. For an opaque surface, solar reflectance is complementary to solar absorptance—that is, the ratio of absorbed to total incident solar energy. Several instruments are available for its measurement, in the laboratory on in situ, according to several standard test methods.

5.9K
23 Nov 2021

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