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Topic Review
Mesoamerican Genetic Studies
Mesoamerica is a historically and culturally defined geographic area comprising current central and south Mexico, Belize, Guatemala, El Salvador, and border regions of Honduras, western Nicaragua, and northwestern Costa Rica. The permanent settling of Mesoamerica was accompanied by the development of agriculture and pottery manufacturing (2500 BCE–150 CE), which led to the rise of several cultures connected by commerce and farming. Hence, Mesoamericans probably carried an invaluable genetic diversity partly lost during the Spanish conquest and the subsequent colonial period. Mesoamerican ancient DNA (aDNA) research has mainly focused on the study of mitochondrial DNA in the Basin of Mexico and the Yucatán Peninsula and its nearby territories, particularly during the Postclassic period (900–1519 CE). 
  • 7.3K
  • 24 Nov 2020
Topic Review
Metal Oxide Applications
Metal oxides play a key role in environmental remediation.
  • 7.3K
  • 08 Dec 2020
Topic Review
Direct Contact Condensers
Direct contact heat exchangers can be smaller, cheaper, and have simpler construction than the surface, shell, or tube heat exchangers of the same capacity and can operate in evaporation or condensation modes. For these reasons, they have many practical applications, such as water desalination, heat exchangers in power plants, or chemical engineering devices.
  • 7.3K
  • 23 Dec 2022
Topic Review
Bio-Composites
Bio-composites are degradable, renewable, non-abrasive, and non-toxic, with comparable properties to those of synthetic fiber composites and used in many applications in various fields. Naturals fibers are abundant and have low harvesting costs with adequate mechanical properties. Hazards of synthetic fibers, recycling issues, and toxic byproducts are the main driving factors in the research and development of bio-composites. Bio-composites are fabricated by combining natural fibers in a matrix material. The matrix material can be biodegradable, non-biodegradable, or synthetic. Synthetic matrix materials, along with natural fibers, are used to form hybrid bio-composites.
  • 7.3K
  • 09 Mar 2021
Topic Review
Artemisia vulgaris L. (common mugwort)
Artemisia vulgaris L. (common mugwort) is a species with great importance in the history of medicine and was called the “mother of herbs” in the Middle Ages. It is a common herbaceous plant that exhibits high morphological and phytochemical variability depending on the location it occurs. This species is well known almost all over the world. Its herb—Artemisiae vulgaris herba—is used as a raw material due to the presence of volatile oil, flavonoids, and sesquiterpene lactones and their associated biological activities. The European Pharmacopoeia has listed this species as a potential homeopathic raw material. Moreover, this species has been used in traditional Chinese, Hindu, and European medicine to regulate the functioning of the gastrointestinal system and treat various gynecological diseases. The general aim of this review was to analyze the progress of phytochemical and pharmacological as well as professional scientific studies focusing on A. vulgaris. Thus far, numerous authors have confirmed the beneficial properties of A. vulgaris herb extracts, including their antioxidant, hepatoprotective, antispasmolytic, antinociceptive, estrogenic, cytotoxic, antibacterial, and antifungal effects. In addition, several works have reviewed the use of this species in the production of cosmetics and its role as a valuable spice in the food industry. 
  • 7.3K
  • 05 Nov 2020
Topic Review
Technoversal Leadership
Technoversal Leadership is a theory that goes beyond leader-follower interactions and business concerns such as growth and profit. This style has a discipline to a global understanding of biodiversity loss, climate, and environmental consciousness and the leader rising with them; Technoversal Leadership theory roots where these global crises, technology, and adaptable qualities intersect.
  • 7.3K
  • 29 Jul 2022
Topic Review
Minimalist Program
In linguistics, the minimalist program (MP) is a major line of inquiry that has been developing inside generative grammar since the early 1990s, starting with a 1993 paper by Noam Chomsky. Chomsky presents MP as a program, not as a theory, following Imre Lakatos's distinction. The MP seeks to be a mode of inquiry characterized by the flexibility of the multiple directions that its minimalism enables. Ultimately, the MP provides a conceptual framework used to guide the development of linguistic theory. In minimalism, Chomsky attempts to approach universal grammar from below—that is, proposing the question "what would be the optimal answer to what the theory of i-Language should be?" For Chomsky, there are minimalist questions, but the answers can be framed in any theory. Of all these questions, the two that play the most crucial role are:
  • 7.3K
  • 20 Nov 2022
Topic Review
Sexual Fetishism
Sexual fetishism or erotic fetishism is a sexual fixation on a nonliving object or nongenital body part. The object of interest is called the fetish; the person who has a fetish for that object is a fetishist. A sexual fetish may be regarded as a non-pathological aid to sexual excitement, or as a mental disorder if it causes significant psychosocial distress for the person or has detrimental effects on important areas of their life. Sexual arousal from a particular body part can be further classified as partialism. While medical definitions restrict the term sexual fetishism to objects or body parts, fetish can, in common discourse, also refer to sexual interest in specific activities.
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  • 14 Oct 2022
Topic Review
Infrared Heating Applications in Food Processing
Infrared (IR) technology is highly energy-efficient, less water-consuming, and environmentally friendly compared to conventional heating. Further, it is also characterized by homogeneity of heating, high heat transfer rate, low heating time, low energy consumption, improved product quality, and food safety. Infrared technology is used in many food manufacturing processes, such as drying, boiling, heating, peeling, polyphenol recovery, freeze-drying, antioxidant recovery, microbiological inhibition, sterilization grains, bread, roasting of food, manufacture of juices, and cooking food. 
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  • 17 Dec 2021
Topic Review
Skin-Lightening Active Ingredients in Japan
Japanese pharmaceutical cosmetics, often referred to as quasi-drugs, contain skin-lightening active ingredients formulated to prevent sun-induced pigment spots and freckles. Their mechanisms of action include suppressing melanin production in melanocytes and promoting epidermal growth to eliminate melanin more rapidly. For example, arbutin and rucinol are representative skin-lightening active ingredients that inhibit melanin production, and disodium adenosine monophosphate and dexpanthenol are skin-lightening active ingredients that inhibit melanin accumulation in the epidermis. In contrast, oral administration of vitamin C and tranexamic acid in pharmaceutical products can lighten freckles and melasma, and these products are more effective than quasi-drugs. On the basis of their clinical effectiveness, skin-lightening active ingredients can be divided into four categories according to their effectiveness and adverse effects.
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  • 08 Aug 2022
Topic Review
Proofs Involving the Moore–Penrose Inverse
In linear algebra, the Moore–Penrose inverse is a matrix that satisfies some but not necessarily all of the properties of an inverse matrix. This article collects together a variety of proofs involving the Moore–Penrose inverse.
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  • 01 Dec 2022
Topic Review
Precambrian Supereon
The Precambrian (or Pre-Cambrian, sometimes abbreviated pЄ, or Cryptozoic) is the earliest part of Earth's history, set before the current Phanerozoic Eon. The Precambrian is so named because it preceded the Cambrian, the first period of the Phanerozoic eon, which is named after Cambria, the Latinised name for Wales, where rocks from this age were first studied. The Precambrian accounts for 88% of the Earth's geologic time. The Precambrian (colored green in the timeline figure) is an informal unit of geologic time, subdivided into three eons (Hadean, Archean, Proterozoic) of the geologic time scale. It spans from the formation of Earth about 4.6 billion years ago (Ga) to the beginning of the Cambrian Period, about 541 million years ago (Ma), when hard-shelled creatures first appeared in abundance.
  • 7.3K
  • 18 Oct 2022
Topic Review
Machine Learning Techniques in Cybersecurity
Machine learning is of rising importance in cybersecurity. The primary objective of applying machine learning in cybersecurity is to make the process of malware detection more actionable, scalable and effective than traditional approaches, which require human intervention. The cybersecurity domain involves machine learning challenges that require efficient methodical and theoretical handling. Several machine learning and statistical methods, such as deep learning, support vector machines and Bayesian classification, among others, have proven effective in mitigating cyber-attacks. The detection of hidden trends and insights from network data and building of a corresponding data-driven machine learning model to prevent these attacks is vital to design intelligent security systems.
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  • 01 Aug 2022
Topic Review
High Frequency Active Auroral Research Program
The High Frequency Active Auroral Research Program (HAARP) was initiated as an ionospheric research program jointly funded by the United States Air Force , the U.S. Navy, the University of Alaska Fairbanks, and the Defense Advanced Research Projects Agency (DARPA). It was designed and built by BAE Advanced Technologies (BAEAT). Its original purpose was to analyze the ionosphere and investigate the potential for developing ionospheric enhancement technology for radio communications and surveillance. As a university-owned facility, HAARP is a high-power, high-frequency transmitter used for study of the ionosphere. The most prominent instrument at HAARP is the Ionospheric Research Instrument (IRI), a high-power radio frequency transmitter facility operating in the high frequency (HF) band. The IRI is used to temporarily excite a limited area of the ionosphere. Other instruments, such as a VHF and a UHF radar, a fluxgate magnetometer, a digisonde (an ionospheric sounding device), and an induction magnetometer, are used to study the physical processes that occur in the excited region. Work on the HAARP facility began in 1993. The current working IRI was completed in 2007; its prime contractor was BAE Systems Advanced Technologies. As of 2008, HAARP had incurred around $250 million in tax-funded construction and operating costs. In May 2014, it was announced that the HAARP program would be permanently shut down later in the year. After discussions between the parties, ownership of the facility and its equipment was transferred to the University of Alaska Fairbanks in August 2015. HAARP is a target of conspiracy theorists, who claim that it is capable of "weaponizing" weather. Commentators and scientists say that advocates of this theory are uninformed, as claims made fall well outside the abilities of the facility, if not the scope of natural science.
  • 7.3K
  • 21 Nov 2022
Topic Review
Basalt
Basalt (/bəˈsɔːlt, ˈbæsɒlt, -sɔːlt/) is a mafic extrusive igneous rock formed from the rapid cooling of magnesium-rich and iron-rich lava exposed at or very near the surface of a terrestrial planet or a moon. More than 90% of all volcanic rock on Earth is basalt. Basalt lava has a low viscosity, due to its low silica content, resulting in rapid lava flows that can spread over great areas before cooling and solidification. Flood basalt describes the formation in a series of lava basalt flows.
  • 7.3K
  • 09 Nov 2022
Topic Review
Criticism of Facebook
Facebook (and parent company Meta Platforms) has been the subject of criticism and legal action. Criticisms include the outsize influence Facebook has on the lives and health of its users and employees, as well as Facebook's influence on the way media, specifically news, is reported and distributed. Notable issues include Internet privacy, such as use of a widespread "like" button on third-party websites tracking users, possible indefinite records of user information, automatic facial recognition software, and its role in the workplace, including employer-employee account disclosure. The use of Facebook can have negative psychological effects that include feelings of sexual jealousy, and stress, a lack of attention, and social media addiction that in some cases is comparable to drug addiction. Facebook's operations have also received coverage. The company's electricity usage, tax avoidance, real-name user requirement policies, censorship policies, handling of user data, and its involvement in the United States PRISM surveillance program have been highlighted by the media and by critics. Facebook has come under scrutiny for 'ignoring' or shirking its responsibility for the content posted on its platform, including copyright and intellectual property infringement, hate speech, incitement of rape, violence against minorities, terrorism, fake news, Facebook murder, crimes, and violent incidents live-streamed through its Facebook Live functionality. The company and its employees have also been subject to litigation cases over the years, with its most prominent case concerning allegations that CEO Mark Zuckerberg broke an oral contract with Cameron Winklevoss, Tyler Winklevoss, and Divya Narendra to build the then-named "HarvardConnection" social network in 2004, instead allegedly opting to steal the idea and code to launch Facebook months before HarvardConnection began. The original lawsuit was eventually settled in 2009, with Facebook paying approximately $20 million in cash and 1.25 million shares. A new lawsuit in 2011 was dismissed. Some critics point to problems which they say will result in the demise of Facebook. Facebook has been banned by several governments for various reasons, including Syria, China, Iran and Russia.
  • 7.3K
  • 14 Oct 2022
Topic Review
Carbon Anode
Carbon anode refers to a broad family of essentially pure carbon, whose members can be tailored to vary widely in their strength, density, conductivity, pore structure, and crystalline development. These attributes contribute to their widespread applicability. Specific characteristics are imparted to the finished product by controlling the selection of precursor materials (including cokes, polymers and fibers) and the method of processing. In general, carbon anode electrodes are characterized by low cost production, high surface area, a wide working potential window in many media, high electrocatalytic activities for different redox-active chemical and biochemical systems, and chemical inertness.Moreover, their surface chemistry enables the functionalization of these carbon platforms via strong covalent or noncovalent methods with surface modifiers, which improves their electrochemical performance. Recent achievements of carbon anode materials and their structural design for better performances of aluminium production, lithium-ion secondary batteries, lithium cobalt oxide batteries, nano-tube production, substitution of amorphous electrode materials, photoanodes production, solar cells, fuel cells, supercapacitors, sensors and pumps, neurochemical monitors, etc., are finding enormous applications in industrial, commercial and social sectors. 
  • 7.3K
  • 31 Aug 2021
Topic Review
Aestheticization of Violence
The aestheticization of violence in high culture art or mass media has been the subject of considerable controversy and debate for centuries. In Western art, graphic depictions of the Passion of Christ have long been portrayed, as have a wide range of depictions of warfare by later painters and graphic artists. Theater and, in modern times, cinema have often featured battles and violent crimes, while images and descriptions of violence have always been a part of literature. Margaret Bruder states that the aestheticization of violence in film is the depiction of violence in a "stylistically excessive", "significant and sustained way" in which audience members are able to connect references from the "play of images and signs" to artworks, genre conventions, cultural symbols, or concepts.
  • 7.3K
  • 15 Nov 2022
Topic Review
The Challenges and Opportunities of Era 5.0
People are in an increasingly disruptive context, in an Era in which the world presents challenging and growing levels of uncertainty, unpredictability, and complexity. As a result, society is facing, at all levels and in all areas, more and more global challenges, challenging its stability and prosperity, whether at a technological, economic, social, environmental, or educational level. The new Era, Era 5.0, which places the human being at the center of innovation and technological transformation, can and must make its contribution to improving the quality of life, solving social problems, and human well-being, with the support of technology.
  • 7.3K
  • 09 Dec 2022
Topic Review
List of R1a Frequency by Population
Haplogroup R1a is one of the major classifications (called clades) of Y-chromosome types found in human male lines. It is widespread all across Eurasia. Many sample studies therefore carry information on the incidence of R1a and/or its subclassifications, in particular the dominant branching line represented by the haplogroups R1a1 and R1a1a. The table below collates information from a number of such sample studies, with incidence frequencies in sample data reported as percentages, along with the associated sample sizes.
  • 7.3K
  • 09 Nov 2022
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