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Topic Review
Combinatorial Peptide Library
Completely randomizing even relatively short peptides would require a library size surpassing the capacities of most platforms. Sampling the complete mutational space for peptides exceeding 8–9 residues is therefore practically impossible, and gene diversification strategies only allow for generation and subsequent interrogation of a limited subset of the entire theoretical peptide population. Directed evolution of peptides therefore strives to ascend towards peak activity through mutational steps, accumulating beneficial mutational over several generations, resulting in improved phenotype. We briefly discuss combinatorial library platforms and take an in-depth look at diversification techniques for random and focused mutagenesis. 
  • 6.3K
  • 30 Oct 2020
Topic Review
Materials Science, Glasses
Glasses are solid amorphous materials which transform into liquids upon heating through the glass transition. The International Commission on Glass defines glass as a state of matter, usually produced when a viscous molten material is cooled rapidly to below its glass transition temperature, with insufficient time for a regular crystal lattice to form. The solid-like behaviour of glasses is separated from the liquid-like behaviour at higher temperatures by the glass transition temperature, Tg. The IUPAC Compendium on Chemical Terminology defines glass transition as a second order transition in which a supercooled melt yields, on cooling, a glassy structure. It states that below the glass-transition temperature the physical properties of glasses vary in a manner similar to those of the crystalline phase. Moreover, it is deemed that the bonding structure of glasses has the same symmetry signature in terms of Hausdorff-Besikovitch dimensionality of chemical bonds as for the crystalline materials. 
  • 6.3K
  • 09 May 2024
Topic Review
2020 Nintendo Data Leak
The 2020 Nintendo data leak, more commonly referred to as the Nintendo Gigaleak is a series of leaks of data from Japanese video game company Nintendo on the anonymous imageboard website 4chan. The releasing of data started in March 2018, but became most prominent in 2020. Nine main sets of data leaked on 4chan, ranging from game and console source code to internal documentation and development tools. The name "Gigaleak" mainly refers to the second leak on July 24, 2020, which was 3 gigabytes in size. The leaks are believed to have come either from companies contracted by Nintendo in the design of these consoles, or from individuals previously convicted of intrusion into Nintendo systems. An earlier, much smaller leak had also occurred in 2018 which had the Nintendo Space World 1997 demos for Pokémon Gold and Silver leaked. The leaks are infamous for the sheer size and the amount of internal material leaked; video game journalists have described the magnitude of the leaks as unprecedented, and suggested that they might have significant effects for emulation and to preservationists, in addition to the legal questions posed by the leak. As of May 2021, Nintendo has not made any official response.
  • 6.3K
  • 14 Oct 2022
Topic Review
Euler–Mascheroni Constant
The Euler–Mascheroni constant (also called Euler's constant) is a mathematical constant recurring in analysis and number theory, usually denoted by the lowercase Greek letter gamma (γ). It is defined as the limiting difference between the harmonic series and the natural logarithm, denoted here by [math]\displaystyle{ \log: }[/math] Here, [math]\displaystyle{ \lfloor x\rfloor }[/math] represents the floor function. The numerical value of the Euler–Mascheroni constant, to 50 decimal places, is: 0.57721566490153286060651209008240243104215933593992... 
  • 6.3K
  • 02 Dec 2022
Topic Review
Electrocommunication
Electrocommunication is the communication method used by weakly-electric fish. Weakly-electric fish are a group of animals that utilize a communicating channel that is "invisible" to most other animals: electric signaling. Electric fish communicate by generating an electric field that a second individual receives with its electroreceptors. The fish interprets the message using the signal's frequencies, waveforms, delay, etc. The best studied species are two freshwater lineages- the African Mormyridae and the South American Gymnotiformes. While weakly-electric fish are the only group that have been identified to carry out both generation and reception of electric fields, other species either generate signals or receive them, but not both. Animals that either generate or receive electric fields are found only in wet or aquatic environments due to water's relatively low electrical resistance, compared to other substances (e.g. air). So far, communication between electric fish has been identified mainly to serve the purpose of conveying information such as: species courtship and biological sex motivational status (e.g. attack warning, submission, etc.) environmental conditions
  • 6.3K
  • 31 Oct 2022
Topic Review
West African Lungfish (Protopterus spp.)
The west african lungfish refers to species of freshwater fishes in the genus Protopterus, belonging to the subclass Dipnoi. These fishes are notable for their unique ability to respire using both gills and lungs, a feature that has attracted considerable scientific attention due to its evolutionary significance. Native to various freshwater habitats across Africa, African lungfishes represent a lineage of sarcopterygian fishes with deep evolutionary connections to the origins of tetrapods.
  • 6.3K
  • 15 Sep 2025
Topic Review
Hydrometallurgy of Lithium Batteries
Spent lithium batteries can cause pollution to the soil and seriously threaten the safety and property of people. They contain valuable metals, such as cobalt and lithium, which are nonrenewable resources, and their recycling and treatment have important economic, strategic, and environmental benefits. The hydrometallurgy process uses reagents such as hydrochloric acid (HCl), nitric acid (HNO3), sulfuric acid (H2SO4), phosphoric acid (H3PO4), organic acids, and hydrogen peroxide (H2O2) to extract and separate the cathode metals, usually operating below 100 °C, and can recover lithium in addition to the other transition metals.
  • 6.3K
  • 15 Mar 2022
Topic Review
Dracorex
Dracorex is a controversial dinosaur genus of the family Pachycephalosauridae, from the Late Cretaceous of North America. The type (and only known) species is Dracorex hogwartsia, meaning "dragon king of Hogwarts". This dinosaur is named for the wizard school in Harry Potter books. It is known from one nearly complete skull (the holotype TCMI 2004.17.1), as well as four cervical vertebrae: the atlas, third, eighth and ninth. These were discovered in the Hell Creek Formation in South Dakota by three amateur paleontologists from Sioux City, in the U.S. state of Iowa. The skull was subsequently donated to the Children's Museum of Indianapolis for study in 2004, and was formally described by Bob Bakker and Robert Sullivan in 2006. However, Jack Horner et al. suspect that it is a juvenile Pachycephalosaurus and an analysis of pachycephalosaur fossils by a joint team from the University of California, Berkeley and the Museum of the Rockies has questioned the validity of two named genera of pachycephalosaur, Dracorex and Stygimoloch. According to the team, specimens of Dracorex and Stygimoloch might actually represent earlier growth stages of Pachycephalosaurus. This has been supported in a 2016 analysis of the youngest Pachycephalosaurus material known, which indicates that the unique features of Dracorex represent instead ontogenetically variant features on a Pachycephalosaurus growth curve.
  • 6.3K
  • 03 Nov 2022
Topic Review
Islamic Primary Schools in the Netherlands
Because of the constitutional Freedom of education in the Netherlands, everyone can establish a school and is entitled to full state funding. There now are 52 primary Islamic schools, with around 12,500 pupils mostly of Turkish and Moroccan descent. They focus on developing an Islamic religious identity, and high educational quality and pupil achievement. Because most pupils come from socioeconomic disadvantaged backgrounds, the schools receive nearly twice as much budget than schools with a predominantly non-disadvantaged population. The existence of Islamic schools has always been controversial. Their output in terms of academic achievement is relatively high, however. In an absolute sense they achieve below the “average” Dutch school, but when compared with schools with the same disadvantaged pupil population, they achieve better. Lately, there have been problems with secondary Islamic schools in the Netherlands. As a result, several politicians propose to abolish the Freedom of education act.  
  • 6.3K
  • 03 Nov 2020
Topic Review
One-Dimensional (1D) Nanostructured Materials
At present, the world is at the peak of production of traditional fossil fuels. Much of the resources that humanity has been consuming (oil, coal, and natural gas) are coming to an end. The human being faces a future that must necessarily go through a paradigm shift, which includes a progressive movement towards increasingly less polluting and energetically viable resources. In this sense, nanotechnology has a transcendental role in this change. For decades, new materials capable of being used in energy processes have been synthesized, which undoubtedly will be the cornerstone of the future development of the planet.
  • 6.3K
  • 23 Jun 2021
Topic Review
Irreligion
Irreligion or nonreligion is the absence or rejection of religion, or indifference to it. Irreligion takes many forms, ranging from the casual and unaware to full-fledged philosophies such as atheism and agnosticism, secular humanism and antitheism. Social scientists tend to define irreligion as a purely naturalist worldview that excludes a belief in anything supernatural. The broadest and loosest definition, serving as an upper limit, is the lack of religious identification, though many non-identifiers express metaphysical and even religious beliefs. The narrowest and strictest is subscribing to positive atheism. According to the Pew Research Center's 2012 global study of 230 countries and territories, 16% of the world's population does not identify with any religion. The population of the religiously unaffiliated, sometimes referred to as "nones", grew significantly in recent years. Measurement of irreligiosity requires great cultural sensitivity, especially outside the West, where the concepts of "religion" or "the secular" are not always rooted in local culture.
  • 6.3K
  • 17 Nov 2022
Topic Review
Phosphate-Solubilizing Microorganisms in Agriculture
Phosphates are known to be essential for plant growth and development, with phosphorus compounds being involved in various physiological and biochemical reactions. Phosphates are known as one of the most important factors limiting crop yields.
  • 6.2K
  • 24 Aug 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. 
  • 6.2K
  • 22 Sep 2022
Topic Review
Independent Legal Reasoning in Islamic Law
Ijtihad (Arabic: اجتهاد ijtihād, [ʔidʒ.tihaːd]; lit. physical or mental effort) is an Islamic legal term referring to independent reasoning by an expert in Islamic law, or the thorough exertion of a jurist's mental faculty in finding a solution to a legal question. It is contrasted with taqlid (imitation, conformity to legal precedent). According to classical Sunni theory, ijtihad requires expertise in the Arabic language, theology, revealed texts, and principles of jurisprudence (usul al-fiqh), and is not employed where authentic and authoritative texts (Qur'an and Hadith) are considered unambiguous with regard to the question, or where there is an existing scholarly consensus (ijma). Ijtihad is considered to be a religious duty for those qualified to perform it. An Islamic scholar who is qualified to perform ijtihad is called a mujtahid. Throughout the first five Islamic centuries, the practice of ijtihad continued both theoretically and practically amongst Sunni Muslims. The controversy surrounding ijtihad and the existence of mujtahids started, in its primitive form, around the beginning of the sixth/twelfth century. By the 14th century, development of Sunni jurisprudence prompted leading Sunni jurists to state that the main legal questions had been addressed and the scope of ijtihad was gradually restricted. In the modern era, this gave rise to a perception among Western scholars and lay Muslim public that the so-called "gate of ijtihad" was closed at the start of the classical era. While recent scholarship established that the practice of Ijtihad had never ceased in Islamic history, the extent and mechanisms of legal change in the post-formative period remain a subject of debate. Differences amongst the jurists prevented Muslims from reaching any consensus(Ijma) on the issues of continuity of Ijtihad and existence of Mujtahids. Thus, Ijtihad remained a key aspect of Islamic jurisprudence throughout the centuries. Ijtihad was practiced throughout the Early modern period and claims for ijtihad and its superiority over taqlid were voiced unremittingly. Starting from the 18th century, Islamic reformers began calling for abandonment of taqlid and emphasis on ijtihad, which they saw as a return to Islamic origins. Public debates in the Muslim world surrounding ijtihad continue to the present day. The advocacy of ijtihad has been particularly associated with Islamic modernist and Salafiyya movements. Among contemporary Muslims in the West there have emerged new visions of ijtihad which emphasize substantive moral values over traditional juridical methodology. Shia jurists did not use the term ijtihad until the 12th century. With the exception of Zaydi jurisprudence, the early Imami Shia were unanimous in censuring Ijtihad in the field of law (Ahkam). After the Shiite embracal of various doctrines of Mu'tazila and classical Sunnite Fiqh (jurisprudence), this led to a change. After the victory of the Usulis who based law on principles (usul) over the Akhbaris ("traditionalists") who emphasized on reports or traditions (khabar) by the 19th century, Ijtihad would become a mainstream Shia practice.
  • 6.2K
  • 22 Nov 2022
Topic Review
Traditional Mexican Diet
Grains, legumes, and vegetables were the most representative food groups in the traditional Mexican diet (TMexD), as these were mentioned in most (75%) of the studies, including all the subgroups evaluated. Additionally, maize (mostly as tortillas), beans, squash, tomato, chile, and onion are potentially fundamental elements of the TMexD, as these were the only individual foods cited in most studies, including all the subgroups evaluated. Indeed, maize (a grain), beans (a legume), and squash (a vegetable) have long represented the basic foods in Mexico, as they form part of the ancient agro-ecosystem known as Milpa. Other groups that were also mentioned in all the studies and subgroup analyses were maize products, fruits, beverages, fish and seafood, meats, sweets and sweeteners, and herbs and condiments. However, these were mentioned in different frequencies in the different subgroups assessed (i.e., in ≥75% of studies in some subgroups while in only 50% of studies in others). 
  • 6.2K
  • 05 Aug 2021
Topic Review
Around the World Sailing Record
The first around the world sailing record for circumnavigation of the world was Juan Sebastián Elcano and the remaining members of Ferdinand Magellan's crew who completed their journey in 1522. The first solo record was set by Joshua Slocum in the Spray (1898). The current record holders are IDEC 3, skippered by Francis Joyon in 40 days, 23 hours, 30 minutes and 30 seconds for a crewed journey, and François Gabart with Macif in 42 days, 16 hours, 40 minutes and 35 seconds for a solo journey. Most races or solo attempts start from Europe. Due to the configuration of the continents, sailing around the world consists of sailing on the Southern Ocean around the Antarctica continent, passing south of Cape Horn, Cape of Good Hope and Cape Leeuwin. Since 1918 the Panama Canal is an option but the locks must be entered and exited using engine power. Large stretches of the canal can be crossed under sail power. Sailing around the world can be done by two directions: eastward or westward. The dominant winds and currents (outside tropical areas) make the voyage eastwards on the Southern hemisphere faster, most skippers and yachts who race prefer this route. Today, the multihulls perform much better than monohulls and hold the best times. Leisure yacht skippers who prefer tropical seas more often go westward, using the trade winds (and the Panama canal). The Jules Verne Trophy is awarded to the skipper who breaks the previous Jules Verne record, starting from an imaginary line between the Créac'h lighthouse on Ouessant (Ushant) Island, France , and the Lizard Lighthouse, United Kingdom . This has not always been the OUTRIGHT record. The records are homologated by the World Sailing Speed Record Council (WSSRC). According to the WSSRC, for around the world sailing records, there is a rule saying that the length must be at least 21,600 nmi calculated along the shortest possible track from the starting port and back that does not cross land and does not go below 63°S. The great-circle distance formulas are to be used, assuming that the great circle length is 21,600 nmi. It is allowed to have one single waypoint to lengthen the calculated track. The equator must be crossed. In reality, this means that the boat should pass a waypoint at or not far from the antipode of the starting port of the journey (the exact position depends on how short the shortest possible track is). For example, the Vendée Globe starts at 46°N 2°W, has a waypoint at 57°S 180°E, and barely makes the distance requirement. The participants don't have to go to the antipode at 46°S 178°E since the rounding of Africa gives extra distance.
  • 6.2K
  • 11 Nov 2022
Topic Review
COTS-Based Architectural Framework
This research tackles issues such as the reliability and efficiency of real-time control systems based on commercial off-the-shelf (COTS) components. A strong emphasis is placed on finding novel efficient solutions based on standardized and commercially available off-the-shelf hardware/software components. In this direction, this research applies credible and feasible methodologies (e.g., model-based design, component-based design, formal verification, real-time scheduling, prototyping, and validation) in an innovative enhanced way. As an important outcome, a versatile integrative design approach and architectural framework (VIDAF) is proposed, which supports the development and implementation of reliable real-time control systems and applications using commercial off-the-shelf components. The feasibility and applicability of the proposed system’s architecture are evaluated and validated through a system application in embedded real-time control in manufacturing. The research outcomes are expected to have a positive impact on emerging areas such as the Industrial Internet of Things (IIoT).
  • 6.2K
  • 28 Oct 2020
Topic Review
Scunthorpe Problem
The Scunthorpe problem is the unintentional blocking of websites, e-mails, forum posts or search results by a spam filter or search engine because their text contains a string (or substring) of letters that appear to have an obscene or otherwise unacceptable meaning. Names, abbreviations, and technical terms are most often cited as being affected by the issue. The problem arises since computers can easily identify strings of text within a document, but interpreting words of this kind requires considerable ability to interpret a wide range of contexts, possibly across many cultures, which is an extremely difficult task. As a result, broad blocking rules may result in false positives affecting innocent phrases.
  • 6.2K
  • 14 Oct 2022
Topic Review
Antibody–Drug Conjugates
An armed antibody or antibody–drug conjugate (ADC) is a vectorized chemotherapy, which results from the grafting of a cytotoxic agent onto a monoclonal antibody via a judiciously constructed spacer arm. ADCs have made considerable progress in 10 years. While in 2009 only gemtuzumab ozogamicin (Mylotarg®) was used clinically, in 2020, 9 Food and Drug Administration (FDA)-approved ADCs are available, and more than 80 others are in active clinical studies. This review will focus on FDA-approved ADCs, their limitations including their toxicity and associated resistance mechanisms, as well as new emerging strategies to address these issues and attempt to widen their therapeutic window. Finally, we will discuss their combination with conventional chemotherapy or checkpoint inhibitors, to allow ADCs to get a little closer to the magic bullet imagined by Paul Ehrlich at the beginning of the 20th century.
  • 6.2K
  • 10 Apr 2021
Topic Review
Detection of Adulteration of Honey
Nowadays, adulteration of honey is a major concern among authorities in order to ensure its quality by imposing specific standards that allow the honey to be competitive in the market. Traditionally, the identification of adulteration of honey is performed by physicochemical methods. However, spectroscopic techniques are considerably more practical when detecting impurities in honey due to fraudulent acts, as these techniques are easy to execute,  more rapid, and more reliable than physicochemical methods.
  • 6.2K
  • 17 Jan 2022
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