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Topic Review Peer Reviewed
Marine Fungi: Opportunities and Challenges
Marine fungi play a crucial role in energy flow and nutrient recycling, mediating the cycling of dissolved organic matter in marine environments. However, despite being a prolific group of organisms, marine fungi have been largely neglected for a long time. Besides their importance in the marine food web, marine fungi represent an active source of natural products. Over the last years, researchers have focused on studying marine organisms to discover new metabolites with antibacterial, antiviral, and anticancer activities. Moreover, with the advances in high-throughput sequencing technologies and mass spectrometry techniques, genomic and metabolomic approaches have revealed to be of paramount importance in natural products discovery. The marine mycobiome includes many organisms still to be identified, and the ones already known are still underutilized in biotechnological applications. For this reason, it is undeniable that exploring the marine mycobiome including new habitats and substrates, even those of remote access, is fundamental for describing the true magnitude of the Earth’s mycobiome.
  • 4.4K
  • 13 Apr 2022
Topic Review
Access Economy
The access economy is a business model where goods and services are traded on the basis of access rather than ownership: it refers to renting things temporarily rather than selling them permanently. The term arose as a correction to the term sharing economy because major players in the sharing economy, such as Airbnb, Zipcar, and Uber, are commercial enterprises whose businesses do not involve any sharing. This model uses a technology platform, often accessed via mobile phone, to connect suppliers willing to rent assets (e.g., apartments for rent or cars for transportation services) with consumers. This movement was worth around $26 billion a year in 2015. The number of persons involved in the access economy is not easily measured. The "access economy" or "on-demand economy" poses regulatory and political challenges, such as: defining the nature of the employment relationship; designing regulations to safeguard parties to these transactions; the loss of taxes and corporate access that results from moving away from small locally owned companies to large remote technology companies; and the bypassing of local regulations (such as the requirement for taxi drivers to provide wheelchair vans, or provide drivers 24-7).
  • 4.4K
  • 04 Nov 2022
Topic Review
Social Closure
Social closure refers to the process by which groups or social categories seek to establish and maintain boundaries to protect their privileged position and restrict access to resources, opportunities, or social status. This phenomenon involves mechanisms such as exclusion, discrimination, or credentialism, aimed at preserving the advantages of certain groups while limiting the mobility and opportunities of others. Social closure can manifest in various domains, including education, employment, and social institutions, contributing to social stratification and inequality within societies.
  • 4.4K
  • 08 Feb 2024
Topic Review
Central African Lion
The Central African lion is a Panthera leo leo population in northern parts of Central and East Africa. This population has been fragmented into small and isolated groups since the 1950s. It is threatened by loss of habitat and prey base and trophy hunting. In 2005, a Lion Conservation Strategy was developed for West and Central Africa. Results of phylogeographic research indicate that the Central African lion clade forms a phylogenetic group with lion samples from West and North Africa, the Middle East and India . This group diverged from lions in southern parts of East and Southern Africa at least 50,000 years ago. Morphometric analysis of lion skulls corroborates the assessment of two major evolutionary lion clusters, one in Sub-Saharan Africa and the other in North Africa and Asia.
  • 4.4K
  • 31 Oct 2022
Topic Review
Euro
The euro (sign: €; code: EUR) is the official currency of 19 of 27 member states of the European Union, as well as some of the territories of the EU. This group of states is known as the eurozone or euro area. It is the second largest and second most traded currency in the foreign exchange market after the United States dollar . The euro is subdivided into 100 cents. The currency is also officially used by the institutions of the European Union and its territories, four other European countries, as well as unilaterally by two others, and is consequently used daily by some 343 million Europeans (As of 2018). Outside Europe, a number of overseas territories of EU members also use the euro as their currency. Additionally, 240 million people worldwide (As of 2018) use currencies pegged to the euro. The euro is the second largest reserve currency as well as the second most traded currency in the world after the United States dollar. (As of August 2018), with more than €1.2 trillion in circulation, the euro has one of the highest combined values of banknotes and coins in circulation in the world, having surpassed the U.S. dollar.[note 14] The name euro was officially adopted on 16 December 1995 in Madrid. The euro was introduced to world financial markets as an accounting currency on 1 January 1999, replacing the former European Currency Unit (ECU) at a ratio of 1:1 (US$1.1743). Physical euro coins and banknotes entered into circulation on 1 January 2002, making it the day-to-day operating currency of its original members, and by May 2002 it had completely replaced the former currencies. While the euro dropped subsequently to US$0.83 within two years (26 October 2000), it has traded above the U.S. dollar since the end of 2002, peaking at US$1.60 on 18 July 2008. In late 2009, the euro became immersed in the European sovereign-debt crisis, which led to the creation of the European Financial Stability Facility as well as other reforms aimed at stabilising and strengthing the currency.
  • 4.4K
  • 23 Nov 2022
Topic Review
Homophily
Homophily is the tendency for individuals to associate and form social bonds with others who share similar characteristics or traits, such as age, gender, ethnicity, education level, or interests. This phenomenon reflects the natural inclination of individuals to seek out and interact with others who are like themselves, contributing to the formation of homogenous social networks and communities.
  • 4.4K
  • 08 Feb 2024
Topic Review Peer Reviewed
Ladislaus II Jagiełło (1386–1434)
Ladislaus II Jagiełło (1386–1434). Ladislaus II Jagiełło is the founder of the Jagiellonian dynasty that had ruled over Poland and the Grand Duchy of Lithuania (until 1572), Bohemia (1471–1526) and Hungary (1440–1444, 1490–1526). A Grand Duke of Lithuania from 1377, and from 1386 a king of Poland and lord of Lithuania, which he ruled jointly with his cousin Witold (Vytautas), the son of Kęstutis. Five medieval portraits of Jagiełło survive, four of which date from the period of his reign in the Polish–Lithuanian state and one was executed posthumously. The earliest image, on Jagiełło’s Great Seal, was made in connection with his coronation as king of Poland (1386). Two portraits in the Holy Trinity Chapel at the Castle of Lublin (1418) are part of a wall paintings scheme commissioned by the monarch and executed by a team of painters brought from Ruthenia. Furthermore, the sumptuous tomb (before 1430) in Cracow was commissioned by the king. Its top slab bears an effigy of Jagiełło with his suggestively rendered countenance, which undoubtedly reflects the actual facial features of the elderly monarch. An image of the king represented as one of the Three Magi in a panel of an altarpiece in the tomb chapel of Casimir IV Jagiellonian, Jagiełło’s son and his successor on the Polish throne, dates from 1470. The chapel dedicated to the Holy Cross, erected at Cracow Cathedral, was in all likelihood commissioned by Casimir himself and his consort Elizabeth of Austria. 
  • 4.4K
  • 13 Apr 2022
Topic Review
Life Cycle Assessment of State-of-the-Art Steel Production Routes
Using the life cycle assessment (LCA) methodology, the impacts of the primary steel production via the blast furnace route and the scrap-based secondary steel production via the electric arc furance (EAF) route are assessed. Methodological as well as technical differences are analysed and their impacts on the results.
  • 4.4K
  • 08 Nov 2022
Topic Review
Cell Cycle
The cell cycle is the series of events that take place in a cell, which drives it to divide and produce two new daughter cells. The typical cell cycle in eukaryotes is composed of the following phases: G1, S, G2, and M phase.
  • 4.4K
  • 03 Dec 2021
Topic Review
Repeated SARS Outbreaks in China
Within last 17 years two widespread epidemics of severe acute respiratory syndrome (SARS) occurred in China, which were caused by related coronaviruses (CoVs): SARS-CoV and SARS-CoV-2. Although the origin(s) of these viruses are still unknown and their occurrences in nature are mysterious, some general patterns of their pathogenesis and epidemics are noticeable. Both viruses utilize the same receptor—angiotensin-converting enzyme 2 (ACE2)—for invading human bodies. Both epidemics occurred in cold dry winter seasons celebrated with major holidays, and started in regions where dietary consumption of wildlife is a fashion. Thus, if bats were the natural hosts of SARS-CoVs, cold temperature and low humidity in these times might provide conducive environmental conditions for prolonged viral survival in these regions concentrated with bats. The widespread existence of these bat-carried or -released viruses might have an easier time in breaking through human defenses when harsh winter makes human bodies more vulnerable. Once succeeding in making some initial human infections, spreading of the disease was made convenient with increased social gathering and holiday travel. These natural and social factors influenced the general progression and trajectory of the SARS epidemiology. However, some unique factors might also contribute to the origination of SARS in Wuhan. These factors are discussed in different scenarios in order to promote more research for achieving final validation.
  • 4.4K
  • 01 Nov 2020
Topic Review
Applications of Photosynthetic Systems
       In biological and life science applications photosynthesis is an important process that involves the absorption and transformation of sunlight into chemical energy. During the photosynthesis process, the light photons are captured by the green chlorophyll pigments in their photosynthetic antennae and further funneled to the reaction center. One of the mostimportant light harvesting complexes that are highly important in the study of photosynthesis is the membrane-attached Fenna-Matthews-Olson (FMO) complex found in the green sulfur bacteria. In this review, we discuss the mathematical formulations and computational modeling of some of the light harvesting complexes including FMO. The most recent research developments in the photosynthetic light harvesting complexes are thoroughly discussed. The theoretical background related to the spectral density, quantum coherence and density functional theory (DFT) has been elaborated.Further, details about the transfer and excitation of energy in different sites of the FMO complex along with other vital photosynthetic light harvesting complexes have also been provided. In particular, we will review recent results on spectral density, quantum coherence, quantum entanglement and excitonic energies of different pigments in the light harvesting complexes. We will also discuss the issues pertinent to the highest occupied orbital (HOMO) and lowest unoccupiedorbital (LUMO) energies for all the bacteriochlorophyll utilizing the time-dependent DFT. These results would be helpful in studying the excitonic dynamics of the light harvesting complexes among different applications. Finally, we conclude this review by providing the current and potential applications in environmental science, energy, health and medicine, where such mathematical and computational studies of the photosynthesis and the light harvesting complexes can be readily integrated.
  • 4.4K
  • 26 Oct 2020
Topic Review
The Mechanisms of Clozapine-Induced Neutropenia
Despite its severe adverse effects, such as agranulocytosis, clozapine is the primary treatment for treatment-resistant schizophrenia. Clozapine is the gold standard for treatment-resistant schizophrenia. It was discovered over a half-century ago by researchers at Wander AG, a Swiss pharmaceutical company. After a decade, the use of clozapine began to fade away due to its alarming side effect but was re-introduced in the year 1989 for the treatment of refractory psychosis. Numerous comparative studies between clozapine and other antipsychotics have reported superior efficacy of clozapine in treatment-resistant schizophrenia.
  • 4.4K
  • 10 Nov 2021
Topic Review
Microneedles
Microneedles (MNs) represent micron-sized structures, consisting of a variety of materials, that have been recently emerged as physical enhances for a painless and safe transdermal delivery of drugs through the skin.
  • 4.4K
  • 02 Dec 2020
Topic Review
Jump Point Search Algorithm
The JPS algorithm is a pathfinding algorithm that uses pruned neighbor rules as the search direction of nodes and the position of forced neighbors as the judgment of jump points.
  • 4.4K
  • 21 Jun 2022
Topic Review
Sadhu
A sadhu (IAST: sādhu (male), sādhvī or sādhvīne (female)), also spelled saddhu, is a religious ascetic, mendicant (monk) or any holy person in Hinduism and Jainism who has renounced the worldly life. They are sometimes alternatively referred to as jogi, sannyasi or vairagi. It literally means one who practises a ″sadhana″ or keenly follows a path of spiritual discipline. Although the vast majority of sādhus are yogīs, not all yogīs are sādhus. The sādhu is solely dedicated to achieving mokṣa (liberation), the fourth and final aśrama (stage of life), through meditation and contemplation of Brahman. Sādhus often wear simple clothing, such saffron-coloured clothing in Hinduism, white or nothing in Jainism, symbolising their sannyāsa (renunciation of worldly possessions). A female mendicant in Hinduism and Jainism is often called a sadhvi, or in some texts as aryika.
  • 4.4K
  • 10 Nov 2022
Topic Review
Flocculation Harvesting Techniques for Microalgae
Microalgae have been considered as one of the most promising biomass feedstocks for various industrial applications such as biofuels, animal/aquaculture feeds, food supplements, nutraceuticals, and pharmaceuticals. Several biotechnological challenges associated with algae cultivation, including the small size and negative surface charge of algal cells as well as the dilution of its cultures, need to be circumvented, which increases the cost and labor. Therefore, efficient biomass recovery or harvesting of diverse algal species represents a critical bottleneck for large-scale algal biorefinery process. Among different algae harvesting techniques (e.g., centrifugation, gravity sedimentation, screening, filtration, and air flotation), the flocculation-based processes have acquired much attention due to their promising efficiency and scalability. 
  • 4.4K
  • 13 Sep 2020
Topic Review
DEFLATE
In computing, Deflate is a lossless data compression file format that uses a combination of LZSS and Huffman coding. It was designed by Phil Katz, for version 2 of his PKZIP archiving tool. Deflate was later specified in RFC 1951 (1996). Katz also designed the original algorithm used to construct Deflate streams. This algorithm was patented as U.S. Patent 5,051,745, and assigned to PKWARE, Inc. As stated in the RFC document, an algorithm producing Deflate files was widely thought to be implementable in a manner not covered by patents. This led to its widespread use, for example in gzip compressed files and PNG image files, in addition to the ZIP file format for which Katz originally designed it. The patent has since expired.
  • 4.4K
  • 11 Oct 2022
Topic Review
Raksha Bandhan
Raksha Bandhan, also Rakshabandhan, or Rakhi, is a popular, traditionally Hindu, annual rite, or ceremony, which is central to a festival of the same name, celebrated in parts of South Asia, and among people influenced by South Asian culture around the world. On this day, sisters of all ages tie a talisman, or amulet, called the rakhi, around the wrists of their brothers, symbolically protecting them, receiving a gift in return, and traditionally investing the brothers with a share of the responsibility of their potential care. Raksha Bandhan is observed on the last day of the Hindu lunar calendar month of Shraavana, which typically falls in August. The expression "Raksha Bandhan," Sanskrit, literally, "the bond of protection, obligation, or care," is now principally applied to this ritual. Until the mid-20th-century, the expression was more commonly applied to a similar ritual, also held on the same day, with precedence in ancient Hindu texts, in which a domestic priest ties amulets, charms, or threads on the wrists of his patrons, or changes their sacred thread, and receives gifts of money; in some places, this is still the case. In contrast, the sister-brother festival, with origins in folk culture, had names which varied with location, with some rendered as Saluno, Silono, and Rakri. A ritual associated with Saluno included the sisters placing shoots of barley behind the ears of their brothers. Of special significance to married women, Raksha Bandhan is rooted in the practice of territorial or village exogamy, in which a bride marries out of her natal village or town, and her parents, by custom, do not visit her in her married home. In rural north India, where village exogamy is strongly prevalent, large numbers of married Hindu women travel back to their parents' homes every year for the ceremony. Their brothers, who typically live with the parents or nearby, sometimes travel to their sisters' married home to escort them back. Many younger married women arrive a few weeks earlier at their natal homes and stay until the ceremony. The brothers serve as lifelong intermediaries between their sisters' married and parental homes, as well as potential stewards of their security. In urban India, where families are increasingly nuclear, the festival has become more symbolic, but continues to be highly popular. The rituals associated with this festival have spread beyond their traditional regions and have been transformed through technology and migration, the movies, social interaction, and promotion by politicized Hinduism, as well as by the nation state. Among women and men who are not blood relatives, there is also a transformed tradition of voluntary kin relations, achieved through the tying of rakhi amulets, which have cut across caste and class lines, and Hindu and Muslim divisions. In some communities or contexts, other figures, such as a matriarch, or a person in authority, can be included in the ceremony in ritual acknowledgement of their benefaction.
  • 4.4K
  • 18 Oct 2022
Topic Review Peer Reviewed
Energy Storage Flywheel Rotors – Mechanical Design
Definition: Energy storage flywheel systems are mechanical devices that typically utilize an electrical machine (motor/generator unit) to convert electrical energy in mechanical energy and vice versa. Energy is stored in a fast-rotating mass known as the flywheel rotor. The rotor is subject to high centripetal forces requiring careful design, analysis, and fabrication to ensure the safe operation of the storage device.
  • 4.4K
  • 13 Apr 2022
Topic Review
Photon
A photon (from grc φῶς, φωτός  'light') is an elementary particle that is a quantum of the electromagnetic field, including electromagnetic radiation such as light and radio waves, and the force carrier for the electromagnetic force. Photons are massless,[lower-alpha 1] so they always move at the speed of light in vacuum, 299792458 m/s (or about 186,282 mi/s). The photon belongs to the class of bosons. Like all elementary particles, photons are currently best explained by quantum mechanics, and exhibit wave–particle duality, their behavior featuring properties of both waves and particles. The modern photon concept originated during the first two decades of the 20th century with the work of Albert Einstein, who built upon the research of Max Planck. While trying to explain how matter and electromagnetic radiation could be in thermal equilibrium with one another, Planck proposed that the energy stored within a material object should be regarded as composed of an integer number of discrete, equal-sized parts. To explain the photoelectric effect, Einstein introduced the idea that light itself is made of discrete units of energy. In 1926, Gilbert N. Lewis popularized the term photon for these energy units. Subsequently, many other experiments validated Einstein's approach. In the Standard Model of particle physics, photons and other elementary particles are described as a necessary consequence of physical laws having a certain symmetry at every point in spacetime. The intrinsic properties of particles, such as charge, mass, and spin, are determined by gauge symmetry. The photon concept has led to momentous advances in experimental and theoretical physics, including lasers, Bose–Einstein condensation, quantum field theory, and the probabilistic interpretation of quantum mechanics. It has been applied to photochemistry, high-resolution microscopy, and measurements of molecular distances. Moreover, photons have been studied as elements of quantum computers, and for applications in optical imaging and optical communication such as quantum cryptography.
  • 4.4K
  • 23 Oct 2022
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