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Topic Review
Spirulina for Skin Care
Spirulina stands out as a sustainable bioactive microalga with health-promoting properties, and an important active ingredient of natural cosmetics products. 
  • 4.5K
  • 05 Feb 2021
Topic Review
Bismuth-213
In contrast to external high energy photon or proton therapy, targeted radionuclide therapy (TRNT) is a systemic cancer treatment allowing targeted irradiation of a primary tumor and all its metastases, resulting in less collateral damage to normal tissues. The α-emitting radionuclide bismuth-213 (213Bi) has interesting properties and can be considered as a magic bullet for TRNT. 
  • 4.5K
  • 11 Jun 2021
Topic Review
Microgrids Configurations and Topologies
Microgrids have been proposed as a solution to the growing deterioration of traditional electrical power systems and the energy transition towards renewable sources. During the design of an microgrid (MG), the components and physical arrangement must be considered to achieve a proper transition between the different modes of operation. The connection of the loads, the microgenerators, and the storage elements, require rigorous analysis to obtain the operation and the desired efficiency by the network operator and the user. The way to interconnect all the elements of the network is known as MG topology.
  • 4.5K
  • 19 Apr 2022
Topic Review
East African Lion
The East African lion is a Panthera leo melanochaita population in East Africa. During the 20th century, lion populations in this part of Africa became fragmented and declined in several range countries due to loss of habitat and prey base, poaching and killing of lions to protect livestock and human life. In 2005, a Lion Conservation Strategy was developed for East and Southern Africa. Today, lion populations are stable only in large protected area complexes. The scientific name P. l. melanochaita was proposed for the Cape lion in 1842 that was eradicated in the mid-19th century. P. l. melanochaita differs genetically from P. leo leo; the two subspecies probably diverged at least 50,000 years ago.
  • 4.5K
  • 01 Dec 2022
Topic Review
Combat History of the T-26
Though nearly obsolete by the beginning of World War II, the T-26 was the most important tank of the Spanish Civil War and played a significant role during the Battle of Lake Khasan in 1938 as well as in the Winter War. The T-26 was the most numerous tank in the Red Army's armoured force during the German invasion of the Soviet Union in June 1941. The Soviet T-26 light tanks last saw combat in August 1945, in Manchuria. The T-26 was used extensively in the armies of Spain, China and Turkey. In addition, captured T-26 light tanks were used by the Finnish, German, Romanian and Hungarian armies.
  • 4.5K
  • 29 Sep 2022
Topic Review
Acetylsalicylic Acid History and Structure
Aspirin (ASA, acetylsalicylic acid ATC code: N02BA01, DrugBank ID: DB00945, brand names: Arthritis Pain, Aspi-Cor, Aspirin 81, Aspirin-Low, Bayer Plus, Bufferin, Ecortin, Eciprin, Miniprin, Vazalore), is one of the first drugs to be obtained by synthesis. It is regarded as, being the most used drug with the longest lasting commercial success.
  • 4.5K
  • 06 Dec 2022
Topic Review Peer Reviewed
Tsunami Alert Efficiency
“Tsunami Alert Efficiency” is the rapid, accurate and reliable conduct of tsunami warning messaging, from the detection of potential tsunamigenic earthquakes to dissemination to all people under threat, and the successful survival of every person at risk on the basis of prior awareness and preparedness.
  • 4.5K
  • 13 Apr 2022
Topic Review
Storm Botnet
The Storm botnet or Storm worm botnet (also known as Dorf botnet and Ecard malware) was a remotely controlled network of "zombie" computers (or "botnet") that had been linked by the Storm Worm, a Trojan horse spread through e-mail spam. At its height in September 2007, the Storm botnet was running on anywhere from 1 million to 50 million computer systems, and accounted for 8% of all malware on Microsoft Windows computers. It was first identified around January 2007, having been distributed by email with subjects such as "230 dead as storm batters Europe," giving it its well-known name. The botnet began to decline in late 2007, and by mid-2008 had been reduced to infecting about 85,000 computers, far less than it had infected a year earlier. As of December 2012, the original creators of Storm have not been found. The Storm botnet has displayed defensive behaviors that indicated that its controllers were actively protecting the botnet against attempts at tracking and disabling it, by specifically attacking the online operations of some security vendors and researchers who had attempted to investigate it. Security expert Joe Stewart revealed that in late 2007, the operators of the botnet began to further decentralize their operations, in possible plans to sell portions of the Storm botnet to other operators. It was reportedly powerful enough to force entire countries off the Internet, and was estimated to be capable of executing more instructions per second than some of the world's top supercomputers. The United States Federal Bureau of Investigation considered the botnet a major risk to increased bank fraud, identity theft, and other cybercrimes.
  • 4.5K
  • 11 Oct 2022
Topic Review
Sources for the Historicity of Jesus
Christian sources, such as the New Testament books in the Christian Bible, include detailed stories about Jesus but scholars differ on the historicity of specific episodes described in the Biblical accounts of Jesus. The only two events subject to "almost universal assent" are that Jesus was baptized by John the Baptist and was crucified by the order of the Roman Prefect Pontius Pilate. Non-Christian sources that are used to study and establish the historicity of Jesus include Jewish sources such as Josephus, and Roman sources such as Tacitus. These sources are compared to Christian sources such as the Pauline Epistles and the Synoptic Gospels. These sources are usually independent of each other (e.g. Jewish sources do not draw upon Roman sources), and similarities and differences between them are used in the authentication process. In a review of the state of research, the Jewish scholar Amy-Jill Levine stated that "no single picture of Jesus has convinced all, or even most scholars" and that all portraits of Jesus are subject to criticism by some group of scholars.
  • 4.5K
  • 23 Nov 2022
Topic Review
Alternatives to Evolution by Natural Selection
Alternatives to evolution by natural selection, also described as non-Darwinian mechanisms of evolution, have been proposed by scholars investigating biology since classical times to explain signs of evolution and the relatedness of different groups of living things. The alternatives in question do not deny that evolutionary changes over time are the origin of the diversity of life, nor deny that the organisms alive today share a common ancestor from the distant past (or ancestors, in some proposals); rather, they propose alternative mechanisms of evolutionary change over time, arguing against mutations acted on by natural selection as the most important driver of evolutionary change. (In most cases, they do not deny that mutations or natural selection occur, or that they play a role in evolutionary change, but instead deny that they are fully sufficient primary causes for the evidence of evolutionary change that is observed in the natural world.) This distinguishes them from certain other kinds of arguments that deny that large scale evolution of any sort has taken place, as in some forms of creationism, which do not propose alternative mechanisms of evolutionary change but instead deny that evolutionary change has taken place at all. Not all forms of creationism deny that evolutionary change takes places; notably, proponents of theistic evolution, such as the biologist Asa Gray, assert that evolutionary change does occur and is responsible for the history of life on Earth, with the proviso that this process has been influenced by a god or gods in some meaningful sense. Where the fact of evolutionary change was accepted but the mechanism proposed by Charles Darwin, natural selection, was denied, explanations of evolution such as Lamarckism, catastrophism, orthogenesis, vitalism, structuralism and mutationism (called saltationism before 1900) were entertained. Different factors motivated people to propose non-Darwinian mechanisms of evolution. Natural selection, with its emphasis on death and competition, did not appeal to some naturalists because they felt it immoral, leaving little room for teleology or the concept of progress in the development of life. Some who came to accept evolution, but disliked natural selection, raised religious objections. Others felt that evolution was an inherently progressive process that natural selection alone was insufficient to explain. Still others felt that nature, including the development of life, followed orderly patterns that natural selection could not explain. By the start of the 20th century, evolution was generally accepted by biologists but natural selection was in eclipse. Many alternative theories were proposed, but biologists were quick to discount theories such as orthogenesis, vitalism and Lamarckism which offered no mechanism for evolution. Mutationism did propose a mechanism, but it was not generally accepted. The modern synthesis a generation later claimed to sweep away all the alternatives to Darwinian evolution, though some have been revived as molecular mechanisms for them have been discovered.
  • 4.5K
  • 09 Oct 2022
Topic Review
Messaging Apps
Messaging apps (a.k.a. social messaging or chat applications) are apps and platforms that enable instant messaging. Messaging apps are online messaging services used primarily via mobile platforms. Many such apps have developed into broad platforms enabling status updates, chatbots, payments and conversational commerce (e-commerce via chat). They are normally centralised networks run by the servers of the platform's operators, unlike peer-to-peer protocols like XMPP. Some examples of popular messaging apps include WhatsApp, Facebook Messenger, China's WeChat and QQ Messenger, Telegram, Viber, Line, and Snapchat. The popularity of certain apps greatly differ between different countries. Certain apps have emphasis on certain uses - for example Skype focuses on video calling, Slack focuses on messaging and file sharing for work teams, and Snapchat focuses on image messages. Some social networking services offer messaging services as a component of their overall platform, such as Facebook's Facebook Messenger, while others have a direct messaging function as an additional adjunct component of their social networking platforms, like Instagram, Reddit, Tumblr, TikTok, Clubhouse and Twitter, either directly or through chat rooms. Messaging apps are the most widely used smartphone apps, with in 2018 over 1.3 billion monthly users of WhatsApp and Facebook Messenger, 980 million monthly active users of WeChat and 843 million monthly active users of QQ Mobile.
  • 4.5K
  • 09 Nov 2022
Topic Review
Building Domain-Specific Search Engines
With advances in machine learning, knowledge discovery systems have become very complicated to set up, requiring extensive tuning and programming effort. Democratizing such technology so that non-technical domain experts can avail themselves of these advances in an interactive and personalized way is an important problem. myDIG is a highly modular, open source pipeline-construction system that is specifically geared towards investigative users (e.g., law enforcement) with no programming abilities. The myDIG system allows users both to build a knowledge graph of entities, relationships, and attributes for illicit domains from a raw HTML corpus and also to set up a personalized search interface for analyzing the structured knowledge. Both qualitative and quantitative data from five case studies involving investigative experts from illicit domains, such as securities fraud and illegal firearms sales, have been used to illustrate the potential of myDIG.
  • 4.5K
  • 10 Feb 2021
Topic Review
Properties and Characteristics of C6F12O
In order to cope with the problem that no gas fire suppressant can be used in the future, perfluoro-2-methyl-3-pentanone (C6F12O), also known as FK-5112, Novec 1230 or Novec 649, with its environmentally friendly performance, zero ODP, GWP of approximately one and atmospheric lifetime of up to two weeks (as shown in Table 1), has been considered as the next generation of halon alternatives. C6F12O belongs to fluorinated ketones which is different to HFCs. Its nontoxicity, noncombustibility, excellent insulation properties and fire suppression efficiency have attracted worldwide attention. The thermophysical parameters, safety and environmental issues and other properties such as the dispersion characteristics of C6F12O are important indexes to evaluate whether it is appropriate to replace the halon. Meanwhile, these properties and parameters are critical to determine the application scenes of fire suppressant, the selection of fire extinguishment facilities and the engineering calculation of the fire extinguishment system.
  • 4.5K
  • 18 Apr 2022
Topic Review
Theoretical Foundations of Smart Village
The smart village is defined as a village in which the efforts of inhabitants and institutions are supported and integrated with information technology systems and innovation to benefit local communities. The idea of the smart village is most often associated with objectives such as improvements in welfare, energy savings, a low-emission economy, a reduction in inequalities between urban and rural areas, and an improvement in economic conditions.
  • 4.5K
  • 25 Jul 2022
Topic Review
Kepler (Spacecraft)
Kepler is a space observatory launched by NASA to discover Earth-size planets orbiting other stars. Named after astronomer Johannes Kepler, the spacecraft was launched on March 7, 2009, into an Earth-trailing heliocentric orbit. The principal investigator was William J. Borucki. Designed to survey a portion of our region of the Milky Way to discover Earth-size exoplanets in or near habitable zones and estimate how many of the billions of stars in the Milky Way have such planets, Kepler's sole scientific instrument is a photometer that continually monitors the brightness of approx 150,000 main sequence stars in a fixed field of view. These data are transmitted to Earth, then analyzed to detect periodic dimming caused by exoplanets that cross in front of their host star. Kepler is part of NASA's Discovery Program of relatively low-cost, focused primary science missions. The telescope's construction and initial operation were managed by NASA's Jet Propulsion Laboratory, with Ball Aerospace responsible for developing the Kepler flight system. The Ames Research Center is responsible for the ground system development, mission operations since December 2009, and scientific data analysis. The initial planned lifetime was 3.5 years, but greater-than-expected noise in the data, from both the stars and the spacecraft, meant additional time was needed to fulfill all mission goals. Initially, in 2012, the mission was expected to be extended until 2016, but on July 14, 2012, one of the spacecraft's four reaction wheels used for pointing the spacecraft stopped turning, and completing the mission would only be possible if all other reaction wheels remained reliable. Then, on May 11, 2013, a second reaction wheel failed, disabling the collection of science data and threatening the continuation of the mission. On August 15, 2013, NASA announced that they had given up trying to fix the two failed reaction wheels. This meant the current mission needed to be modified, but it did not necessarily mean the end of planet hunting. NASA had asked the space science community to propose alternative mission plans "potentially including an exoplanet search, using the remaining two good reaction wheels and thrusters". On November 18, 2013, the K2 "Second Light" proposal was reported. This would include utilizing the disabled Kepler in a way that could detect habitable planets around smaller, dimmer red dwarfs. On May 16, 2014, NASA announced the approval of the K2 extension. (As of January 2015), Kepler and its follow-up observations had found 1,013 confirmed exoplanets in about 440 star systems, along with a further 3,199 unconfirmed planet candidates.[upper-alpha 2] Four planets have been confirmed through Kepler's K2 mission. In November 2013, astronomers estimated, based on Kepler space mission data, that there could be as many as 40 billion rocky, Earth-size exoplanets orbiting in the habitable zones of Sun-like stars and red dwarfs within the Milky Way. It is estimated that 11 billion of these planets may be orbiting Sun-like stars. The nearest such planet may be 3.7 parsecs (12 ly) away, according to the scientists. On January 6, 2015, NASA announced the 1,000th confirmed exoplanet discovered by the Kepler Space Telescope. Four of the newly confirmed exoplanets were found to orbit within habitable zones of their related stars: three of the four, Kepler-438b, Kepler-442b and Kepler-452b, are almost Earth-size and likely rocky; the fourth, Kepler-440b, is a super-Earth. On May 10, 2016, NASA verified 1,284 new exoplanets found by Kepler, the single largest finding of planets to date. Kepler data has also helped scientists observe and understand supernovae; measurements were collected every half-hour so the light curves were especially useful for studying these types of astronomical events.
  • 4.5K
  • 20 Oct 2022
Topic Review
Tea EGCG and Coffee CGA
Tea and coffee are consumed worldwide and epidemiological and clinical studies have shown their health beneficial effects, including anti-cancer effects. Epigallocatechin gallate (EGCG) and chlorogenic acid (CGA) are the major components of green tea polyphenols and coffee polyphenols, respectively, and believed to be responsible for most of these effects. Although a large number of cell-based and animal experiments have provided convincing evidence to support the anti-cancer effects of green tea, coffee, EGCG, and CGA, human studies are still controversial and some studies have suggested even an increased risk for certain types of cancers such as esophageal and gynecological cancers with green tea consumption and bladder and lung cancers with coffee consumption. 
  • 4.5K
  • 20 Oct 2020
Topic Review
Root Exudates and Soil Organic Carbon
Root exudates, as an important form of material input from plants to the soil, regulate the carbon input and efflux of plant rhizosphere soil and play an important role in maintaining the carbon and nutrient balance of the whole ecosystem. Root exudates are notoriously difficult to collect due to their underlying characteristics (e.g., low concentration and fast turnover rate) and the associated methodological challenges of accurately measuring root exudates in native soils. As a result, up until now, it has been difficult to accurately quantify the soil organic carbon input from root exudates to the soil in most studies. The contribution and ecological effects of root exudates to soil organic carbon input and efflux have been paid more and more attention. 
  • 4.5K
  • 17 Feb 2023
Topic Review
IMAGE
IMAGE (Imager for Magnetopause-to-Aurora Global Exploration) is a NASA Medium Explorers mission that studied the global response of the Earth's magnetosphere to changes in the solar wind. It was believed lost but as of August 2018 might be recoverable. It was launched 25 March 2000 by a Delta II rocket from Vandenberg Air Force Base on a two-year mission. Almost six years later, it unexpectedly ceased operations in December 2005 during its extended mission and was declared lost. The spacecraft was part of NASA's Sun-Earth Connections Program, and during its run had over 400 research articles published in peer-reviewed journals using its data. It had special cameras that provided various breakthroughs in understanding the dynamics of plasma around the Earth. The Principal Investigator was Jim Burch of the Southwest Research Institute. In January 2018, an amateur satellite tracker found it to be transmitting some signals back to Earth. NASA made attempts to communicate with the spacecraft and determine its payload status, but has had to track down and adapt old hardware and software to the current systems. On 25 February, contact with IMAGE was again lost, but if reestablished, NASA may decide to fund a restarted mission.
  • 4.5K
  • 13 Oct 2022
Topic Review
Electromyography
Electromyography (EMG) is a bioelectrical signal to assess electrical activity produced by skeletal muscles. In the study of muscle fatigue, the electrophysiological measurement of muscles play a crucial role in collecting electrical signals from skeletal muscles. Since EMG signals usually contain a certain amount of noise, it is essential to obtain high quality data in the early stage. In addition, people prefer a painless and comfortable method when recording muscle contraction signals.  This review addresses the EMG data collection methods with good quality and less pain, their applications, and the examples of actual EMG data analysis.
  • 4.5K
  • 20 Feb 2021
Topic Review
Pakistan’s Heritage Management
Improving archaeology policies means fostering search and exploration of ancient sites, promoting protection and preservation actions of architectural remains, and management of cultural heritage.
  • 4.5K
  • 19 Apr 2022
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