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Topic Review
Evolution of Dinosaurs
Dinosaurs evolved within a single lineage of archosaurs 243-233 Ma (million years ago) from the Anisian to the Carnian ages, the latter part of the middle Triassic. Dinosauria is a well-supported clade, present in 98% of bootstraps. It is diagnosed by many features including loss of the postfrontal on the skull and an elongate deltopectoral crest on the humerus. In March 2017, scientists reported a new way of classifying the dinosaur family tree, based on newer and more evidence than available earlier. According to the new classification, the original dinosaurs, arising 200 million years ago, were small, two-footed omnivorous animals with large grasping hands. Descendants (for the non-avian dinosaurs) lasted until 66 million years ago.
  • 6.4K
  • 14 Oct 2022
Topic Review
Euro Health Consumer Index
Euro Health Consumer Index (EHCI) is a comparison of European health care systems based on waiting times, results, and generosity. The information is presented as a graphic index. EHCI was produced 2005–2009 and 2012–2016 by Health Consumer Powerhouse. The 2014 ranking included 37 countries measured by 48 indicators. It claims to measure the "consumer friendliness" of healthcare systems. It does not claim to measure which European state has the best healthcare system, but it does produce specialist Indexes on Diabetes, Cardiac Care, HIV, Headache and Hepatitis. In 2006 France was the champion with 768 points out of 1000. In the 2015 results the same performance would have given the 13th position among 35 countries because of the widespread improvements in standards. While no bias in favour of any health system was alleged, the index was criticised in the British Medical Journal by Martin McKee and others from the European Observatory on Health Systems and Policies in February 2016. Points they made included: A survey by the Centre for Population Change in 2019 produced results consistent with the index.
  • 6.4K
  • 09 Nov 2022
Topic Review
The Pathogenesis of Epilepsy
Epilepsy is a chronic neurological disorder characterized by recurring spontaneous seizures. Drug resistance appears in 30% of patients and it can lead to premature death, brain damage or a reduced quality of life. The purpose of the study was to analyze the drug resistance mechanisms, especially neuroinflammation, in the epileptogenesis. The information bases of biomedical literature Scopus, PubMed, Google Scholar and SciVerse were used. To obtain full-text documents, electronic resources of PubMed Central and Research Gate were used. The article examines the recent research of the mechanisms of drug resistance in epilepsy and discusses the hypotheses of drug resistance development (genetic, epigenetic, target hypothesis, etc.). Drug-resistant epilepsy is associated with neuroinflammatory, autoimmune and neurodegenerative processes. Neuroinflammation causes immune, pathophysiological, biochemical and psychological consequences. Focal or systemic unregulated inflammatory processes lead to the formation of aberrant neural connections and hyperexcitable neural networks. Inflammatory mediators affect the endothelium of cerebral vessels, destroy contacts between endothelial cells and induce abnormal angiogenesis (the formation of “leaky” vessels), thereby affecting the blood–brain barrier permeability. Thus, the analysis of pro-inflammatory and other components of epileptogenesis can contribute to the further development of the therapeutic treatment of drug-resistant epilepsy.
  • 6.4K
  • 26 May 2021
Topic Review
Broken/Angular Diameter
The angular diameter, angular size, apparent diameter, or apparent size is an angular measurement describing how large a sphere or circle appears from a given point of view. In the vision sciences, it is called the visual angle, and in optics, it is the angular aperture (of a lens). The angular diameter can alternatively be thought of as the angle through which an eye or camera must rotate to look from one side of an apparent circle to the opposite side. Angular radius equals half of the angular diameter.
  • 6.4K
  • 04 Nov 2022
Topic Review
Militarization of Police
The militarization of police is the use of military equipment and tactics by law enforcement officers. This includes the use of armored personnel carriers (APCs), assault rifles, submachine guns, flashbang grenades, grenade launchers, sniper rifles, and SWAT (special weapons and tactics) teams. The militarization of law enforcement is also associated with intelligence agency–style information gathering aimed at the public and political activists and with a more aggressive style of law enforcement. Criminal justice professor Peter Kraska has defined militarization of police as "the process whereby civilian police increasingly draw from, and pattern themselves around, the tenets of militarism and the military model". Observers have noted the militarizing of the policing of protests. Since the 1970s, riot police have fired at protesters using guns with rubber bullets or plastic bullets. Tear gas, which was developed by the United States Army for riot control in 1919, is still widely used against protesters. The use of tear gas in warfare is prohibited by various international treaties that most states have signed; however, its law enforcement or military use for domestic or non-combat situations is permitted. Concerns about the militarization of police have been raised by both ends of the political spectrum in the United States , with both the libertarian Cato Institute and the American Civil Liberties Union (ACLU) voicing criticisms of the practice. The Fraternal Order of Police has spoken out in favor of equipping law enforcement officers with military equipment, claiming that it increases the officers' safety and enables them to protect members of the public and other first responders (e.g., firefighters and emergency medical services personnel). However, a 2017 study showed that police forces which received military equipment were more likely to have violent encounters with the public, regardless of local crime rates. A 2018 study found that militarized police units in the United States were more frequently deployed to communities with large shares of African-Americans, even after controlling for local crime rates. Many countries also have a gendarmerie, which is a military force with law enforcement duties among the civilian population. France classifies some weapons as "intermediary force weapons" such as its LBD 40 refitted version of the Swiss B&T GL06 military grenade launcher, which is used in riot police situations or against individual persons in more specific interventions. While not having the full power of military guns, some weapons are heavier than regular police weaponry and are still lethal. These are often referred to with the "limited lethality" appellation.
  • 6.4K
  • 11 Oct 2022
Topic Review
Corporate Social Responsibility in Saudi Arabia
In Saudi Arabia, as in the international arena, corporate social responsibility (CSR) is a trending phenomenon that has been transforming and influencing government policies, business strategic management, and societal relationships.
  • 6.4K
  • 13 May 2022
Topic Review
Deep Residual Learning for Image Recognition
In 2015, a deep residual network (ResNet) was proposed for image recognition. It is a type of convolutional neural network (CNN) where the input from the previous layer is added to the output of the current layer. Deep Residual Networks have recently been shown to significantly improve the performance of neural networks trained on ImageNet, with results beating all previous methods on this dataset by large margins in the image classification task. 
  • 6.4K
  • 22 Sep 2022
Topic Review
History of the Aircraft Carrier
Aircraft carriers are warships that evolved from balloon-carrying wooden vessels into nuclear-powered vessels carrying scores of fixed- and rotary-wing aircraft. Since their introduction they have allowed naval forces to project air power great distances without having to depend on local bases for staging aircraft operations. Balloon carriers were the first ships to deploy manned aircraft, used during the 19th and early 20th century, mainly for observation purposes. The advent of fixed-wing aircraft in 1903 was followed in 1910 by the first flight from the deck of a US Navy cruiser. Seaplanes and seaplane tender support ships, such as HMS Engadine, followed. The development of flat top vessels produced the first large fleet ships. This evolution was well underway by the early to mid-1920s, resulting in the commissioning of ships such as Hōshō (1922), HMS Hermes (1924), Béarn (1927), and the Lexington-class aircraft carriers (1927). Most early aircraft carriers were conversions of ships that were laid down (or had even served) as different ship types: cargo ships, cruisers, battlecruisers, or battleships. During the 1920s, several navies started ordering and building aircraft carriers that were specifically designed as such. This allowed the design to be specialized to their future role, and resulted in superior ships. During the Second World War, these ships would become the backbone of the carrier forces of the US, British, and Japanese navies, known as fleet carriers. World War II saw the first large-scale use of aircraft carriers and induced further refinement of their launch and recovery cycle leading to several design variants. The USA built small escort carriers, such as USS Bogue, as a stop-gap measure to provide air support for convoys and amphibious invasions. Subsequent light aircraft carriers, such as USS Independence, represented a larger, more "militarized" version of the escort carrier concept. Although the light carriers usually carried the same size air groups as escort carriers, they had the advantage of higher speed as they had been converted from cruisers under construction.
  • 6.4K
  • 07 Nov 2022
Topic Review
Make
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.
  • 6.4K
  • 28 Sep 2022
Topic Review
Void
Cosmic voids are vast spaces between filaments (the largest-scale structures in the universe), which contain very few or no galaxies. The cosmological evolution of the void regions differs drastically from the evolution of the Universe as a whole: there is a long stage when the curvature term dominates, which prevents the formation of galaxy clusters and massive galaxies. Hence, although even the emptiest regions of voids contain more than ~15% of the average matter density of the Universe, the voids look almost empty for an observer. Voids typically have a diameter of 10 to 100 megaparsecs (30 to 300 million light years); particularly large voids, defined by the absence of rich superclusters, are sometimes called supervoids. They were first discovered in 1978 in a pioneering study by Stephen Gregory and Laird A. Thompson at the Kitt Peak National Observatory. Voids are believed to have been formed by baryon acoustic oscillations in the Big Bang, collapses of mass followed by implosions of the compressed baryonic matter. Starting from initially small anisotropies from quantum fluctuations in the early universe, the anisotropies grew larger in scale over time. Regions of higher density collapsed more rapidly under gravity, eventually resulting in the large-scale, foam-like structure or "cosmic web" of voids and galaxy filaments seen today. Voids located in high-density environments are smaller than voids situated in low-density spaces of the universe. Voids appear to correlate with the observed temperature of the cosmic microwave background (CMB) because of the Sachs–Wolfe effect. Colder regions correlate with voids and hotter regions correlate with filaments because of gravitational redshifting. As the Sachs–Wolfe effect is only significant if the universe is dominated by radiation or dark energy, the existence of voids is significant in providing physical evidence for dark energy.
  • 6.4K
  • 18 Oct 2022
Topic Review
Intermittent Energy Source
An intermittent energy source is any source of energy that is not continuously available for conversion into electricity and outside direct control because the used primary energy cannot be stored. Intermittent energy sources may be predictable but cannot be dispatched to meet the demand of an electric power system. The use of intermittent sources in an electric power system usually displaces storable primary energy that would otherwise be consumed by other power stations. Another option is to store electricity generated by non-dispatchable energy sources for later use when needed, e.g. in the form of pumped storage, compressed air or in batteries. A third option is the sector coupling e.g. by electric heating for district heating schemes. The use of small amounts of intermittent power has little effect on grid operations. Using larger amounts of intermittent power may require upgrades or even a redesign of the grid infrastructure.
  • 6.4K
  • 26 Oct 2022
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."
  • 6.4K
  • 03 Nov 2022
Biography
François Truffaut
François Roland Truffaut (French: [fʁɑ̃.swa ʁɔ.lɑ̃ tʁyfo]; 6 February 1932 – 21 October 1984) was a French film director, screenwriter, producer, actor, and film critic. He is widely regarded as one of the founders of the French New Wave.[1] In a film career lasting over a quarter of a century, he remains an icon of the French film industry, having worked on over 25 films. Truffaut's
  • 6.4K
  • 23 Nov 2022
Topic Review
Sex Ratio
The sex ratio is the ratio of males to females in a population. In most sexually reproducing species, the ratio tends to be 1:1. This tendency is explained by Fisher's principle. For various reasons, however, many species deviate from anything like an even sex ratio, either periodically or permanently. Examples include parthenogenic species, periodically mating organisms such as aphids, some eusocial wasps such as Polistes fuscatus and Polistes exclamans, bees, ants, and termites. The human sex ratio is of particular interest to anthropologists and demographers. In human societies, however, sex ratios at birth may be considerably skewed by factors such as the age of mother at birth, and by sex-selective abortion and infanticide. Exposure to pesticides and other environmental contaminants may be a significant contributing factor as well. As of 2014, the global sex ratio at birth is estimated at 107 boys to 100 girls (1,000 boys per 934 girls).
  • 6.4K
  • 19 Oct 2022
Topic Review
Porridge
Porridge (historically also spelled porage, porrige, or parritch) is a food commonly eaten as a breakfast cereal dish, made by boiling ground, crushed or chopped starchy plants—typically grain—in water or milk. It is often cooked or served with added flavorings such as sugar, honey, (dried) fruit or syrup to make a sweet cereal, or it can be mixed with spices or vegetables to make a savoury dish. It is usually served hot in a bowl, depending on its consistency. Oat porridge, or oatmeal, is one of the most common types of porridge. Gruel is a thinner version of porridge.
  • 6.4K
  • 02 Nov 2022
Topic Review
Jallianwala Bagh: Roots of a Historic Massacre
Today, April 13th, 2025, marks the 106th anniversary of the Jallianwala Bagh Massacre, a day etched in the collective memory of India as a brutal and defining moment in its struggle for independence.
  • 6.4K
  • 13 Apr 2025
Topic Review
Artificial Island Developments
Artificial island development (AID) to tackle rampant urbanization on scarce land puts all marine biodiversity at huge risk and is recognized as a global conservation issue worldwide.
  • 6.4K
  • 16 May 2022
Topic Review
Philosophy of History
Philosophy of history is the philosophical study of history and the past. The term was coined by Voltaire.
  • 6.4K
  • 19 Oct 2022
Topic Review
48,XXYY Syndrome
48,XXYY syndrome is a chromosomal condition that causes infertility, developmental and behavioral disorders, and other health problems in males.
  • 6.4K
  • 23 Dec 2020
Topic Review
Hypocrisy
Hypocrisy is the contrivance of a false appearance of virtue or goodness, while concealing real character or inclinations, especially with respect to religious and moral beliefs; hence, in a general sense, hypocrisy may involve dissimulation, pretense, or a sham. Hypocrisy is the practice of engaging in the same behavior or activity for which one criticizes another. In moral psychology, it is the failure to follow one's own expressed moral rules and principles. According to British political philosopher David Runciman, "Other kinds of hypocritical deception include claims to knowledge that one lacks, claims to a consistency that one cannot sustain, claims to a loyalty that one does not possess, claims to an identity that one does not hold". American political journalist Michael Gerson says that political hypocrisy is "the conscious use of a mask to fool the public and gain political benefit". Hypocrisy has been a subject of folk wisdom and wisdom literature from the beginnings of human history. Increasingly, since the 1980s, it has also become central to studies in behavioral economics, cognitive science, cultural psychology, decision making, ethics, evolutionary psychology, moral psychology, political sociology, positive psychology, social psychology, and sociological social psychology.
  • 6.4K
  • 21 Nov 2022
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