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Topic Review
Crocodile
Crocodiles (family Crocodylidae) or true crocodiles are large semiaquatic reptiles that live throughout the tropics in Africa, Asia, the Americas and Australia. The term crocodile is sometimes used even more loosely to include all extant members of the order Crocodilia, which includes the alligators and caimans (family Alligatoridae), the gharial and false gharial (family Gavialidae) among other extinct taxa. Although they appear similar, crocodiles, alligators and the gharial belong to separate biological families. The gharial, with its narrow snout, is easier to distinguish, while morphological differences are more difficult to spot in crocodiles and alligators. The most obvious external differences are visible in the head, with crocodiles having narrower and longer heads, with a more V-shaped than a U-shaped snout compared to alligators and caimans. Another obvious trait is that the upper and lower jaws of the crocodiles are the same width, and the teeth in the lower jaw fall along the edge or outside the upper jaw when the mouth is closed; therefore, all teeth are visible, unlike an alligator, which possesses in the upper jaw small depressions into which the lower teeth fit. Also, when the crocodile's mouth is closed, the large fourth tooth in the lower jaw fits into a constriction in the upper jaw. For hard-to-distinguish specimens, the protruding tooth is the most reliable feature to define the species' family. Crocodiles have more webbing on the toes of the hind feet and can better tolerate saltwater due to specialized salt glands for filtering out salt, which are present, but non-functioning, in alligators. Another trait that separates crocodiles from other crocodilians is their much higher levels of aggression. Crocodile size, morphology, behaviour and ecology differ somewhat among species. However, they have many similarities in these areas as well. All crocodiles are semiaquatic and tend to congregate in freshwater habitats such as rivers, lakes, wetlands and sometimes in brackish water and saltwater. They are carnivorous animals, feeding mostly on vertebrates such as fish, reptiles, birds and mammals, and sometimes on invertebrates such as molluscs and crustaceans, depending on species and age. All crocodiles are tropical species that, unlike alligators, are very sensitive to cold. They separated from other crocodilians during the Eocene epoch, about 55 million years ago. Many species are at the risk of extinction, some being classified as critically endangered.
  • 6.5K
  • 21 Oct 2024
Topic Review
Cousin
Most generally, in the lineal kinship system used in the English-speaking world, a cousin is a type of familial relationship in which two relatives are two or more familial generations away from their most recent common ancestor. Commonly, "cousin" refers to a first cousin – a relative of the same generation whose most recent common ancestor with the subject is a grandparent. Degrees and removals are separate measures used to more precisely describe the relationship between cousins. Degree measures the separation, in generations, from the most recent common ancestor(s) to a parent of one of the cousins (whichever is closest), while removal measures the difference in generations between the cousins themselves, relative to their most recent common ancestor(s). To illustrate usage, a second cousin is a cousin with a degree of two; there are three (not two) generations from the common ancestor(s). When the degree is not specified, first cousin is assumed. A cousin "once removed" is a cousin with one removal. When the removal is not specified, no removal is assumed. Various governmental entities have established systems for legal use that can precisely specify kinship with common ancestors any number of generations in the past; for example, in medicine and in law, a first cousin is a type of third-degree relative.
  • 6.5K
  • 25 Oct 2022
Topic Review
Verb–Subject–Object
In linguistic typology, a verb–subject–object (VSO) language is one in which the most typical sentences arrange their elements in that order, as in Ate Sam oranges (Sam ate oranges). VSO is the third-most common word order among the world's languages, after SOV (as in Hindi and Japanese) and SVO (as in English and Mandarin). Families where all or many of the languages are VSO include the following: Spanish resembles Semitic languages such as Arabic in allowing for both VSO and SVO structures: "Jesús vino el jueves"/"Vino Jesús el jueves, "Tu madre dice que no vayas"/"Dice tu madre que no vayas". Many languages, such as Greek, have relatively free word order, where VSO is one of many possible orders. Low level programming languages such as assembly tend to follow VSO order in how they assign bits in a memory word. Although the bit sizes vary between architectures, the general form consists of an opcode (verb) followed by a combination of memory or register addresses (subjects) and/or values (objects).
  • 6.5K
  • 04 Nov 2022
Topic Review
Pole Weapon
A pole weapon or pole arm is a close combat weapon in which the main fighting part of the weapon is fitted to the end of a long shaft, typically of wood, thereby extending the user's effective range and striking power. Pole weapons are predominantly melee weapons, with a subclass of spear-like designs fit for both thrusting and throwing. Because many pole weapons were adapted from agricultural implements or other fairly abundant tools, and contained relatively little metal, they were cheap to make and readily available. When warfare would break out and the belligerents had a poorer class who could not pay for dedicated military weapons, leaders would often appropriate tools as cheap weapons. The cost of training was comparatively minimal, since these conscripted farmers had spent most of their lives using these "weapons" in the fields. This made polearms the favored weapon of peasant levies and peasant rebellions the world over. Pole arms can be divided into three broad categories: those designed for extended reach and thrusting tactics used in pike square or phalanx combat; those designed to increase leverage (thanks to hands moving freely on a pole) to maximize centrifugal force against cavalry; and those designed for throwing tactics used in skirmish line combat. Because their versatility, high effectiveness and cheap cost, polearms experimentation led to many variants and were the most frequently used weapons on the battlefield: bills, picks, dane axes, spears, glaives, guandaos, pudaos, poleaxes, halberds, harpoons, sovnyas, tridents, naginatas, bardiches, war scythes, and lances are all varieties of pole arms. Pole arms were common weapons on post-classical battlefields of Asia and Europe. Their range and impact force made them effective weapons against armored warriors on horseback, because they could be dismounted and/or penetrate said armor. The Renaissance saw a plethora of varieties. Pole arms in modern times are largely constrained to ceremonial military units such as the Papal Swiss Guard or Yeomen of the Guard, or traditional martial arts. Chinese martial arts in particular have preserved a wide variety of weapons and techniques.
  • 6.5K
  • 09 Nov 2022
Topic Review
Pre–Indo-European Languages
Pre-Indo-European languages are any of several ancient languages, not necessarily related to one another, that existed in prehistoric Europe and South Asia before the arrival of speakers of Indo-European languages. The oldest Indo-European language texts date from the 19th century BC in Kültepe in modern-day Turkey, and while estimates vary widely, spoken Indo-European languages are believed to have developed at the latest by the third millennium BC (see Proto-Indo-European Urheimat hypotheses). Thus the Pre-Indo-European languages must have developed earlier than, or in some cases alongside, the Indo-European languages that ultimately displaced them. A handful of these languages still survive; in Europe, Basque retains a localized strength with fewer than a million native speakers, while the Dravidian languages of South Asia remain very widespread there, with over 200 million native speakers. Some of the pre-Indo-European languages are attested only as linguistic substrates in Indo-European languages. A few others (such as Etruscan, Minoan, Iberian, etc.) are also attested from inscriptions.
  • 6.5K
  • 02 Nov 2022
Topic Review
Systemic Lupus Erythematosus Pathogenesis
Systemic lupus erythematosus (SLE) is a genetically predisposed, female-predominant disease, characterized by multiple organ damage, that in its most severe forms can be life-threatening. The pathogenesis of SLE is complex and involves cells of both innate and adaptive immunity. The distinguishing feature of SLE is the production of autoantibodies, with the formation of immune complexes that precipitate at the vascular level, causing organ damage. 
  • 6.5K
  • 04 Apr 2023
Topic Review
Metallic Nanowires
The fundamental properties of a material can dramatically change when its dimensions are reduced nanometer scale. Metallic nanowires are one-dimensional nanostructures with diameters that are typically in a range of 10-200 nm, and lengths in a range of 5-100 µm. Metallic nanowires have many unique properties that are not seen in their bulk counterparts, such as good thermal and electrical conductivity, high aspect ratio, low sheet resistance, excellent optical transparency, etc. In the past two decades, research into metallic nanowires has encouraged breakthrough technologies in a variety of fields, including flexible transparent conductive films and electrodes, optoelectronic devices, molecular electronics, solar cells,  touch screens, biomedical science, chemical sensors, heat transfer enhancement, etc.
  • 6.5K
  • 29 Oct 2020
Topic Review
Serer Creation Myth
The Serer creation myth is the traditional creation myth of the Serer people of Senegal, the Gambia and Mauritania. Many Serers who adhere to the tenets of the Serer religion believe these narratives to be sacred. Some aspects of Serer religious and Ndut traditions are included in the narratives contained herein but are not limited to them. Serer creation myth developed from Serer oral traditions, Serer religion, legends, cosmogonies. The specifics of the myth are also found in two main Serer sources: A nax and A leep. The former is a short narrative for a short myth or proverbial expression, whilst the later is for a more developed myth. Broadly, they are equivalent to verbs and logos respectively[clarification needed], especially when communicating fundamental religious education such as the supreme being and the creation of the Universe. In addition to being fixed-Serer sources, they set the structure of the myth. The creation myth of the Serer people is intricately linked to the first trees created on Planet Earth by Roog. Earth's formation began with a swamp. The Earth was not formed until long after the creation of the first three worlds: the waters of the underworld; the air which included the higher world (i.e. the sun, the moon and the stars) and earth. Roog is the creator and fashioner of the Universe and everything in it. The creation is based on a mythical cosmic egg and the principles of chaos.
  • 6.5K
  • 01 Nov 2022
Topic Review
Apoptosis
Apoptosis is a multistep process that involves two major pathways to trigger a cascade of events leading to the fragmentation of chromatin, nuclear membrane, and cell shrinkage. However, when this physiological process tended to be dysregulated, many pathological transformations happen to develop cancer.
  • 6.5K
  • 23 Jun 2021
Topic Review
Fake News and Potentially Manipulative Content
At the core of numerous definitions of fake news lies a statement that it contains information that does not correlate with facts and that it is directed towards disinforming the public in a conscious manner, which implies that the major features of fake news are untruthfulness/incorrectness and intended deception. For this reason, Jaster and Lanuis attribute the lack of truth and lack of truthfulness to the notion of fake news and, using this as a starting point, they claim that fake news is “wrong or deceptive (lack of truth) and that it is released with the intention of deceiving or, eventually, discrediting or neglecting the truth (lack of truthfulness)”. In her efforts to draw a line between fake news and the contents similar to it, Milica Kulić defines the former as “incorrect information containing unprovable, mostly completely fabricated data or claims, as well as quotations, released with a view to deceiving audiences”.
  • 6.5K
  • 26 Jan 2022
Topic Review
The Acquisition of Negation
Although negation in natural languages is a complex and heterogeneous phenomenon, the first instances of linguistic negation appear in children’s speech quite early, by 18 and 24 months of life. Nevertheless, its acquisition is a gradual and challenging process, as it takes time for children to fully grasp the semantic meanings of the different negative words to be able to use them correctly across different sentential contexts. Moreover, in order to understand how to negate a sentence, children must also learn how negation can have scope over different parts of the sentences, leaving the others unaffected. The picture becomes even more complicated for children when multiple negative structures come into play, in which the negative meaning is conveyed by the combination of two (or more) negative elements. The interpretation of these complex syntactic constructions is indeed not always straightforward since a different arrangement of the same negative elements may yield different semantic interpretations of the same sentence.
  • 6.5K
  • 16 Jun 2022
Topic Review
Extended-Range Electric Vehicles
Extended-range electric vehicles (EREVs), commonly known as series hybrid electric vehicles (Series-HEV), have better autonomy than electric vehicles (EV) without range extenders (REs). EREVs can go from one city to another or make long journeys in general.
  • 6.5K
  • 03 Aug 2021
Topic Review
Mechanism of Cotton Combustion
As a cellulose-based polymer, the combustion of cotton is an exothermic oxidation process that takes place upon heating, consuming flammable gases, liquids, and solid residues produced during the pyrolysis of the textile material, thus generating heat.
  • 6.5K
  • 27 Jul 2023
Topic Review
G-Protein-Coupled Receptors
G-protein-coupled receptors (GPCRs), which make up the largest superfamily of human membrane proteins, play pivotal roles in mediating intracellular signaling and inducing cell proliferation, cell growth, and cell motility through the association and subsequent dissociation of G-proteins in response to external stimuli.
  • 6.5K
  • 05 Feb 2021
Topic Review
Love Live
Love Live! School Idol Project is a Japanese multimedia project co-developed by ASCII Media Works' Dengeki G's Magazine, music label Lantis, and animation studio Sunrise. The project revolves around a group of nine schoolgirl friends who become idols in order to save their school from shutting down. It launched in the August 2010 issue of Dengeki G's Magazine, and went on to produce music CDs, anime music videos, two manga adaptations, and video games. A 13-episode anime television series produced by Sunrise, directed by Takahiko Kyōgoku, and written by Jukki Hanada aired in Japan between January and March 2013, with a second season airing between April and June 2014. Both anime series and film are licensed in North America, the United Kingdom, Australia and New Zealand by NIS America, MVM Entertainment and Madman Entertainment, respectively. An animated film titled Love Live! The School Idol Movie was distributed by Shochiku and released in June 2015. A follow-up project focusing on a new set of idols, titled Love Live! Sunshine!!, launched in 2015.
  • 6.5K
  • 20 Oct 2022
Topic Review
Marine Algae and Plants
Marine algae and plants are a diverse collection of marine life that, together with cyanobacteria, form the main primary producers at base of the ocean food chain. Marine primary producers are important because they underpin almost all marine animal life by generating most of the oxygen and food that animals need to exist. Some algae and plants are also ecosystem engineers which change the environment and provide habitats for other marine life. Marine algae includes the largely invisible and often unicellular microalgae, which together with cyanobacteria form the ocean phytoplankton, as well as the larger, more visible and complex multicellular macroalgae commonly called seaweed. Seaweeds are found along coastal areas, living on the floor of continental shelves and washed up in intertidal zones. Some seaweeds drift with plankton in the sunlit surface waters (epipelagic zone) of the open ocean. Back in the Silurian, some phytoplankton evolved into red, brown and green algae. These algae then invaded the land and started evolving into the land plants we know today. Later in the Cretaceous some of these land plants returned to the sea as mangroves and seagrasses. These are found along coasts in intertidal regions and in the brackish water of estuaries. In addition, some seagrasses, like seaweeds, can be found at depths up to 50 metres on both soft and hard bottoms of the continental shelf.
  • 6.5K
  • 20 Oct 2022
Topic Review
Malaysia Waste Management Practices
The three main municipalities of Malaysia, Kuala Lumpur, Penang, and Melaka, were discussed in their actions in household waste management practices and strategies in social, economy, information technology, and governance to achieve success for a better sustainability of the environment.
  • 6.4K
  • 06 Jun 2022
Topic Review
Abnormality (Behavior)
Abnormality (or dysfunctional behavior) is a behavioral characteristic assigned to those with conditions that are regarded as rare or dysfunctional. Behavior is considered to be abnormal when it is atypical or out of the ordinary, consists of undesirable behavior, and results in impairment in the individual's functioning. Abnormality in behavior, is that in which is considered deviant from specific societal, cultural and ethical expectations. These expectations are broadly dependent on age, gender, traditional and societal categorizations. The definition of abnormal behavior is an often debated issue in abnormal psychology, because of these subjective variables. Abnormal behavior should not be confused with unusual behavior. Behavior that is out of the ordinary is not necessarily indicative of a mental or psychological disorder. Abnormal behavior, on the other hand, while not a mental disorder in itself, is often an indicator of a possible mental and/or psychological disorder. A psychological disorder is defined as an "ongoing dysfunctional pattern of thought, emotion, and behavior that causes significant distress, and is considered deviant in that person's culture or society". It is important to note that abnormal behavior, as it relates to psychological disorders, would be "ongoing" and a cause of "significant distress". A mental disorder describes a patient who has a medical condition whereby the medical practitioner makes a judgement that the patient is exhibiting abnormal behavior based on the DSM-5 criteria. Thus, simply because a behavior is unusual it does not make it abnormal; it is only considered abnormal if it meets these criteria. The Diagnostic and Statistical Manual of Mental Disorders, or DSM-5, is used by both researchers and clinicians in diagnosing a potential mental disorder. The criteria needed to be met in the DSM-5 varies for each mental disorder. Unlike physical abnormalities in ones health whose symptoms are objective, psychology health professionals cannot use objective symptoms when evaluating someone for abnormalities in behavior.
  • 6.4K
  • 03 Nov 2022
Topic Review
Wearable Devices for Non-Invasive Sensing
The development of wearable sensors is aimed at enabling continuous real-time health monitoring, which leads to timely and precise diagnosis anytime and anywhere. Unlike conventional wearable sensors that are somewhat bulky, rigid, and planar, research for next-generation wearable sensors has been focused on establishing fully-wearable systems. To attain such excellent wearability while providing accurate and reliable measurements, fabrication strategies should include (1) proper choices of materials and structural designs, (2) constructing efficient wireless power and data transmission systems, and (3) developing highly-integrated sensing systems.
  • 6.4K
  • 09 Feb 2021
Topic Review
Single-Letter Second-Level Domain
Single-letter second-level domains are domain names in which the second-level domain consists of only one letter, such as x.com. In 1993, the Internet Assigned Numbers Authority (IANA) explicitly reserved all single-letter and single-digit second-level domain names in the top-level domains com, net, and org, and grandfathered those that had already been assigned. In December 2005, ICANN considered auctioning these domains.
  • 6.4K
  • 03 Nov 2022
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