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Topic Review
Faster-Than-Light Communication
Superluminal communication is a hypothetical process in which information is sent at faster-than-light (FTL) speeds. The current scientific consensus is that faster-than-light communication is not possible, and to date it has not been achieved in any experiment. Under present knowledge superluminal communication is impossible because, in a Lorentz-invariant theory, it could be used to transmit information into the past. This contradicts causality and leads to logical paradoxes. A number of theories and phenomena related to superluminal communication have been proposed or studied, including tachyons, quantum nonlocality, and wormholes.
  • 5.2K
  • 19 Oct 2022
Topic Review
British Sheep Breed Diversity
The UK can be proud of the fact that numerous native breeds of sheep have been developed here that possess unique phenotypic features and excellent productivity and are utilized throughout the world. Their remarkable popularity and further sustainable breeding on grass pastures of British Isles and elsewhere can benefit from genomic applications. At present, there is a rich arsenal of genetic and genomic resources, tools and applications used for livestock assessment, breeding and production including, first of all, genetic profiling of diverse breeds, and search for quantitative trait loci (QTLs) and candidate genes in farm animals. These genomic advances facilitate breed improvement and understanding of the genetic processes in the course of domestication and breed evolution.
  • 5.2K
  • 27 Feb 2024
Topic Review
Blockchain and Machine Learning for Future Smart Grids
A wide range of solutions, beyond the classical one of building more lines, cables and transformers, have been proposed to modernize the power grid with new technologies, enabling a more smart automatic networked system. These solutions, typically using new technology, go by the name “smart grids” (SG) or “smart-grid technology”. Blockchain technology (BC) is a viable solution to overcome the issues of centralized system. BC is an immutable, distributed and P2P network that provides security, privacy and trust among peers using cryptographic techniques. Machine learning (ML) techniques can be exploited to develop energy prediction algorithms and the proper scheduling of energy usage. A large amount of the energy consumption data of several users is generated from smart meters that also contain users’ private/confidential information as well as sensitive information of utility providers. This high volume of data increases the complexity of data analysis. 
  • 5.2K
  • 27 Feb 2023
Topic Review
Kitakyushu (Japan) of Industrial Heritage Tourism
Japan, Asia’s earliest industrialized country, has been transforming into a post-industrialized society. A large number of former industrial heritages in Japan have been well protected. Three industrial heritages have been listed in World Heritage by UNESCO (United Nations Educational, Scientific and Cultural Organization). Moreover, Japan has the largest number of centennial enterprises in the world, reaching 25,321, much more than that of North America and Europe. Compared with other industrialized countries, Japan’s industrial heritages are generally owned by long-lived enterprises, some of these spaces are still in service. Therefore, centennial enterprises often become the most direct stakeholders in the protection of industrial heritages, and play a key role in the transformation into new industrial space for cultural and touristic activities. In other words, under the influence of centennial enterprises, the development of industrial heritage tourism in Japan generally has strong path dependence.
  • 5.2K
  • 13 Dec 2021
Topic Review
Structure, Spectral Properties and Chemistry of Spiropyrans
Spiropyrans (SP) are a well-studied class of photochromic compounds. These compounds are usually named in conformity with the IUPAC rules for nomenclature of heterocyclic spirocompounds, as derivatives of 1′,3′,3′-trimethyl-6-nitrospiro[2H-1-benzopyran-2,2′-indoline] or 1′,3′-dihydro-1′,3′,3′-trimethyl-6-nitrospiro[2H-1-benzopyran-2,2′-indole].
  • 5.2K
  • 11 Jul 2023
Topic Review
Rainbows in Culture
The rainbow, a natural phenomenon noted for its design and its place in the sky, has been a favorite component of art and religion throughout history.
  • 5.2K
  • 14 Oct 2022
Topic Review
Yandex Self-Driving Car
Yandex self-driving car (Yandex Self-Driving Group) is a robotaxi project of the Russian-based internet corporation Yandex. The first driverless prototype launched in May 2017. As of 2018, functional service was launched in Russia with prototypes also being tested in Israel and the US. In 2019, Yandex revealed autonomous delivery robots based on the same technology stack as the company's self-driving cars. Since 2020, autonomous robots have been delivering food, groceries and parcels in Russia and the USA. In 2020, the self-driving project was spun-off into a standalone company under the name of Yandex Self-Driving Group (Yandex SDG).
  • 5.2K
  • 27 Oct 2022
Topic Review
Left-Brain Interpreter
The left-brain interpreter is a neuropsychological concept developed by the psychologist Michael S. Gazzaniga and the neuroscientist Joseph E. LeDoux. It refers to the construction of explanations by the left brain hemisphere in order to make sense of the world by reconciling new information with what was known before. The left-brain interpreter attempts to rationalize, reason and generalize new information it receives in order to relate the past to the present. Left-brain interpretation is a case of the lateralization of brain function that applies to "explanation generation" rather than other lateralized activities. Although the concept of the left-brain interpreter was initially based on experiments on patients with split-brains, it has since been shown to apply to the everyday behavior of people at large.
  • 5.2K
  • 21 Oct 2022
Topic Review
Photonic Laser Thruster
A photonic laser thruster (PLT) is an amplified photonic propulsion thruster for space propulsion that works on the principle of a photon-pushed sail, generating thrust directly from the momentum of a photon from a laser reflected from a mirror. The thruster, invented by Young K. Bae differs from other solar sail and laser propulsion thrusters in that an amplification process is used, in which the incident beam is re-used by being reflected by a stationary mirror, with an amplification stage at each reflection. Because of the recycling of energy, the photonic laser thruster has been demonstrated to be more energy efficient than other laser-pushed sail concepts. The near-term usage of the photonic laser thruster the earth-orbit applications include propellant-free and thrust-plume-contamination-free spacecraft maneuvering for precision formation flying, large optical and RF synthetic aperture construction, and stationkeeping. The usage of the photonic laser thruster for main space propulsion would require scaling-up of the laser power and controlling laser diffraction over interplanetary and interstellar distances. Photonic laser thrusters have a very high specific impulse, and can permit spacecraft to reach much higher speeds that approach a fraction of the light speed, unlike conventional rockets, which are limited by the Tsiolkovsky rocket equation.
  • 5.2K
  • 01 Nov 2022
Topic Review
Tuskegee Syphilis Experiment
The Tuskegee Study of Untreated Syphilis in the African American Male was a clinical study conducted between 1932 and 1972 by the United States Public Health Service. The purpose of this study was to observe the natural history of untreated syphilis; the African-American men in the study were only told they were receiving free health care from the Federal government of the United States. The Public Health Service started the study in 1932 in collaboration with Tuskegee University (then the Tuskegee Institute), a historically black college in Alabama. Investigators enrolled in the study a total of 600 impoverished, African-American sharecroppers from Macon County, Alabama. Of these men, 399 had latent syphilis, with a control group of 201 men who were not infected. As an incentive for participation in the study, the men were promised free medical care, but were deceived by the PHS, who disguised placebos, ineffective methods, and diagnostic procedures as treatment. The men who had syphilis were never informed of their diagnosis, despite the risk of infecting others, and the fact that the disease could lead to blindness, deafness, mental illness, heart disease, bone deterioration, collapse of the central nervous system, and death.. According to the Centers for Disease Control and Prevention, the men were told that they were being treated for "bad blood,” a colloquialism that described various conditions such as syphilis, anemia and fatigue. "Bad blood"—specifically the collection of illnesses the term included—was a leading cause of death within the southern African-American community. The men were initially told that the study was only going to last six months, but it was extended to 40 years. After funding for treatment was lost, the study was continued without informing the men that they would never be treated. None of the infected men were treated with penicillin despite the fact that by 1947, the antibiotic had become the standard treatment for syphilis. Study clinicians could have chosen to treat all syphilitic subjects and close the study, or split off a control group for testing with penicillin. Instead, they continued the study without treating any participants; they withheld treatment and information about it from the subjects. In addition, scientists prevented participants from accessing syphilis treatment programs available to other residents in the area. The study continued, under numerous Public Health Service supervisors, until 1972, when a leak to the press resulted in its termination on November 16 of that year. The victims of the study, all African-American, included numerous men who died of syphilis, 40 wives who contracted the disease and 19 children born with congenital syphilis. The 40-year Tuskegee Study of Untreated Syphilis in the African American Male study was a major violation of ethical standards. Researchers knowingly failed to treat participants appropriately after penicillin was proven to be an effective treatment for syphilis and became widely available. Moreover, participants remained ignorant of the study clinicians’ true purpose, which was to observe the natural course of untreated syphilis. The revelation in 1972 of study failures by a whistleblower, Peter Buxtun, led to major changes in U.S. law and regulation concerning the protection of participants in clinical studies. Now studies require informed consent, communication of diagnosis and accurate reporting of test results. The Tuskegee Syphilis Study, cited as "arguably the most infamous biomedical research study in U.S. history," led to the 1979 Belmont Report and to the establishment of the Office for Human Research Protections (OHRP). It also led to federal laws and regulations requiring institutional review boards for the protection of human subjects in studies involving them. The OHRP manages this responsibility within the United States Department of Health and Human Services (HHS). On May 16, 1997, President Bill Clinton formally apologized on behalf of the United States to victims of the study.
  • 5.2K
  • 07 Nov 2022
Topic Review
Impact of the Internet on Hip Hop
The World Wide Web has changed the genre of hip hop. It has given hip-hop artists the ability to create and share music at incredible rates. Through the constant influx of new music being posted online by artists, new styles and genres of hip hop have been created.
  • 5.2K
  • 30 Nov 2022
Topic Review
Biodiesel from Castor Oil
An attractive alternative to the use of fossil fuels is biodiesel, which can be obtained from a variety of feedstock through different transesterification systems such as ultrasound, microwave, biological, chemical, among others. The efficient and cost-effective biodiesel production depends on several parameters such as free fatty acid content in the feedstock, transesterification reaction efficiency, alcohol: oil ratio, catalysts type, and several parameters during the production process. However, biodiesel production from vegetable oils is under development, causing the final price of biodiesel to be higher than diesel derived from petroleum. An alternative to decrease the production costs will be the use of economical feedstocks and simple production processes. Castor oil is an excellent raw material in terms of price and quality, but especially this non-edible vegetable oil does not have any issues or compromise food security. Recently, the use of castor oil has attracted attention for producing and optimizing biodiesel production, due to the high content of ricinoleic fatty acid and the possibility to esterify with only methanol, which assures low production costs. Additionally, biodiesel from castor oil has different advantages over conventional diesel. Some of them are biodegradable, non-toxic, renewable, they can be used alone, low greenhouse gas emission, among others. This review discusses and analyzes different transesterification processes, technologies, as well as different technical aspects during biodiesel production using castor oil as a feedstock.
  • 5.2K
  • 28 Oct 2020
Topic Review
Lysenkoism
Lysenkoism (Russian: Лысенковщина, romanized: Lysenkovshchina, [ɫɨˈsɛnkəfɕːʲɪnə], Ukrainian: лисенківщина, Template:IPA-uk) was a political campaign led by Trofim Lysenko against genetics and science-based agriculture in the mid-20th century, rejecting natural selection in favour of a form of Lamarckism, as well as expanding upon the techniques of vernalization and grafting. In time, the term has come to be identified as any deliberate distortion of scientific facts or theories for purposes that are deemed politically, religiously or socially desirable. More than 3,000 mainstream biologists were dismissed or imprisoned, and numerous scientists were executed in the campaign to suppress scientific opponents. The president of the Agriculture Academy, Nikolai Vavilov, who had been Lysenko's mentor, but later denounced him, was sent to prison and died there, while Soviet genetics research was effectively destroyed. Research and teaching in the fields of neurophysiology, cell biology, and many other biological disciplines were harmed or banned. Other countries of the Eastern Bloc including the People's Republic of Poland, the Republic of Czechoslovakia, and the German Democratic Republic accepted Lysenkoism as the official "new biology", to varying degrees, as did the People's Republic of China for some years. The government of the USSR supported the campaign, and Joseph Stalin personally edited a speech by Lysenko in a way that reflected his support for what would come to be known as Lysenkoism, despite his skepticism toward Lysenko's assertion that all science is class-oriented in nature. Lysenko served as the director of the Soviet Union's Lenin All-Union Academy of Agricultural Sciences.
  • 5.2K
  • 02 Nov 2022
Topic Review
Chi square statistic
The Chi-Square test is based on a series of assumptions frequently used in the statistical analysis of experimental data. The main weakness of the chi-square test is that is very accurate only in convergence (in large size samples), and for small sample sizes is exposed to errors of both types (type I and type II). On two scenarios of use - goodness of fit and contingencies assessment (2x2 tables of contingency) - here are discussed different aspects involving it. Further knowledge on the regard of the type of the error in contingencies assessment push further the analysis of the data, while in the same time opens the opportunity to devise a method for filling the gaps in contingencies (e.g. censored data), both scenarios being discussed here in detail. A program designed to fill the gaps in the assumption of the association is provided.
  • 5.2K
  • 24 Dec 2020
Topic Review
Chlorine Dioxide
Chlorine dioxide was discovered in 1811 by Sir Humphry Davy and since the mid-20th century, it has been widely used in the paper industry as a bleach and for the treatment of drinking water. 
  • 5.2K
  • 21 Dec 2022
Topic Review
IoT-Enabled Smart Cities
Smart cities have been significantly developed and have greatly expanded their potential. In fact, novel advancements to the Internet of things (IoT) have paved the way for new possibilities, representing a set of key enabling technologies for smart cities and allowing the production and automation of innovative services and advanced applications for the different city stakeholders. 
  • 5.1K
  • 21 Feb 2022
Topic Review
Western European Colonialism and Colonization
File:SierraLeoneHofstra3.1.tiff European colonialism and colonization was the policy or practice of acquiring full or partial political control over other societies and territories, creating a colony, occupying it with settlers, and exploiting it economically. Research suggests, the current conditions of postcolonial countries have roots in colonial actions and policies. For example, colonial policies, such as the type of rule implemented, the nature of investments, and identity of the colonizers, are cited as impacting postcolonial states. Examination of the state-building process, economic development, and cultural norms and mores shows the direct and indirect consequences of colonialism on the postcolonial states.
  • 5.1K
  • 04 Nov 2022
Topic Review
Species Problem
The species problem is the set of questions that arises when biologists attempt to define what a species is. Such a definition is called a species concept; there are at least 26 recognized species concepts. A species concept that works well for sexually reproducing organisms such as birds is useless for species that reproduce asexually, such as bacteria. The scientific study of the species problem has been called microtaxonomy. One common, but sometimes difficult, question is how best to decide which species an organism belongs to, because reproductively isolated groups may not be readily recognizable, and cryptic species may be present. There is a continuum from reproductive isolation with no interbreeding, to panmixis, unlimited interbreeding. Populations can move forward or backwards along this continuum, at any point meeting the criteria for one or another species concept, and failing others. Many of the debates on species touch on philosophical issues, such as nominalism and realism, and on issues of language and cognition. The current meaning of the phrase "species problem" is quite different from what Charles Darwin and others meant by it during the 19th and early 20th centuries. For Darwin, the species problem was the question of how new species arose. Darwin was however one of the first people to question how well-defined species are, given that they constantly change.
  • 5.1K
  • 02 Nov 2022
Topic Review
The Epididymis
The epididymis is a convoluted, crescent-shaped structure that connects the testis to the vas deferens and has four main anatomical regions each with unique characteristics and functions: the initial segment, caput (head), corpus (body) and cauda (tail).
  • 5.1K
  • 05 Nov 2020
Topic Review
Christian
A Christian (/ˈkrɪstʃən, -tiən/ (listen)) is a person who follows or adheres to Christianity, an Abrahamic, monotheistic religion based on the life and teachings of Jesus Christ. "Christian" derives from the Koine Greek word Christós (Χριστός), a translation of the Biblical Hebrew term mashiach (Biblical Hebrew: מָשִׁיחַ). While there are diverse interpretations of Christianity which sometimes conflict, they are united in believing that Jesus has a unique significance. The term "Christian" is also used as an adjective to describe anything associated with Christianity, or in a proverbial sense "all that is noble, and good, and Christ-like." According to a 2011 Pew Research Center survey, there were 2.2 billion Christians around the world in 2010, up from about 600 million in 1910. By 2050, the Christian population is expected to exceed 3 billion. According to a 2012 Pew Research Center survey Christianity will remain the world's largest religion in 2050, if current trends continue. Today, about 37% of all Christians live in the Americas, about 26% live in Europe, 24% live in sub-Saharan Africa, about 13% live in Asia and the Pacific, and 1% live in the Middle East and North Africa. About half of all Christians worldwide are Catholic, while more than a third are Protestant (37%). Orthodox communions comprise 12% of the world's Christians. Other Christian groups make up the remainder. Christians make up the majority of the population in 158 countries and territories. 280 million Christians live as a minority. Christians have significantly influenced and contributed to human progress in many fields including philanthropy, philosophy,:15 ethics, literature, business and economics, fine arts and architecture, music, theatre and medicine, as well as science and technology, both historically and in modern times.
  • 5.1K
  • 27 Oct 2022
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