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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.
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  • 13 Apr 2022
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.
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  • 21 Jun 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.
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  • 18 Oct 2022
Topic Review
Union of Bulgaria and Romania
The union of Bulgaria and Romania (Bulgarian: Съюз на България и Румъния, romanized: Sǎjúz na Bŭlgariya i Rumŭniya; Romanian: Unirea Bulgariei cu România) was a project for the unification of Bulgaria and Romania into a common state. This would be accomplished under a federation, a personal union or a confederation. The idea had great support, especially in Bulgaria, and there were several opportunities to realize it. Usually, proposals came from Bulgarians and it was the Romanians, who would have composed the ethnic majority, the ones that were supposed to govern. Nevertheless, it ultimately failed to appear mainly due to the differences between Bulgarians and Romanians and the opposition from external powers like Austria-Hungary and especially Russia. This idea had its precedents. Bulgarians and Romanians first lived together under the rule of the First Bulgarian Empire, which extended its power north of the Danube. After the fall of this state would come the Second Bulgarian Empire, established through the cooperation of Bulgarians and Vlachs (Romanians). The empire would also be defeated, this time by the Ottoman Empire, which ruled territories populated by Bulgarians and Romanians for centuries. Later, a popular concept emerged in the Balkans: the federalization of the region, aimed at fighting nearby empires and solving conflicts between its peoples. The idea eventually spread in Bulgaria and Romania, gaining certain support. Several proposals were made; that of Georgi Sava Rakovski stands out. After the establishment of an autonomous Bulgarian principality in 1878, projects with Romania were enhanced. In fact, during the search for the first modern Bulgarian prince, several Romanian nominations came out. These were Carol I, monarch of Romania, and Gheorghe G. Bibescu, son of a Wallachian prince. However, the one who ended up being elected was Alexander of Battenberg, of German origins. Alexander had good relations with Romania, but he was forced to abdicate in 1886 after a period of political turmoil in Bulgaria. This was caused by Russia, which intended to extend its influence over the country. However, Stefan Stambolov, a Russophobe (name of those Bulgarians who opposed Russian policies), ended up taking power. The regent Stambolov tried again to establish a personal union with Romania, and negotiations were conducted. Carol I would be the head of such state, which would have either two separate governments or a single united one. Carol I had interest in becoming ruler of Bulgaria as well, but Russia strongly opposed this. At the end, it threatened Romania with the breakdown of diplomatic relations and even with a military invasion, forcing Carol I to reject the offer. Again, a German prince, Ferdinand I, was elected prince of Bulgaria in June 1887. New approaches were attempted decades later, in the communist era, especially by Georgi Dimitrov, but they all met strong rejection from the Soviet Union. Joseph Stalin , its leader, deemed the proposal as impossible. A Bulgarian-Romanian union was thus never established. The reasons for this were the disapproval of several great powers, the differences in the national goals of the Bulgarians and Romanians and the lack of actual interest or even opposition between each other. In addition, the idea of federalization of the Balkans, which had great support in its time, lost strength all over the region after the conflicts of the beginning of the 20th century and the violent breakup of Yugoslavia. However, the emergence of the European Union, of which Bulgaria and Romania have been members since 2007, has revived such an idea, which could once again be considered in the future.
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  • 21 Nov 2022
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.
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  • 01 Nov 2020
Topic Review
Neural Tube Defects
Neural tube defects (NTDs) are the second most common congenital malformations of humans, characterized by impaired development of the central nervous system. Even though the etiology of most birth defects remains undetermined, genetic and environmental risk factors in the background of NTDs have been identified and extensively reported.
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  • 05 May 2022
Topic Review
Excavation (Archaeology)
In archaeology, excavation is the exposure, processing and recording of archaeological remains. An excavation site or "dig" is a site being studied. Such a site excavation concerns itself with a specific archaeological site or a connected series of sites, and may be conducted over as little as several weeks to over a number of years. Numerous specialized techniques with particular features are used. Resources and other practical issues do not allow archaeologists to carry out excavations whenever and wherever they choose. These constraints mean many known sites have been deliberately left unexcavated. This is with the intention of preserving them for future generations as well as recognising the role they serve in the communities that live near them. Excavation involves the recovery of several types of data from a site. These data include artifacts (objects made or modified by humans), features (modifications to the site itself such as post molds, burials, and hearths), ecofacts (evidence for the local environment and resources being used such as snail shells, seeds, and butchered bones) and, most importantly, archaeological context (relationships among the other types of data). Ideally, data from the excavation should suffice to reconstruct the site completely in three-dimensional space. The presence or absence of archaeological remains can often be suggested by remote sensing, such as ground-penetrating radar. Basic information about the development of the site may be drawn from this work but the understanding of finer features usually requires excavation though appropriate use of augering.
  • 4.4K
  • 30 Nov 2022
Topic Review
Anchovy
An anchovy is a small, common forage fish of the family Engraulidae. Most species are found in marine waters, but several will enter brackish water and some in South America are restricted to fresh water. The more than 140 species are placed in 17 genera; they are found in the Atlantic, Indian and Pacific Oceans, and in the Black Sea and the Mediterranean Sea. Anchovies are usually classified as oily fish.
  • 4.4K
  • 07 Nov 2022
Topic Review
Patient Protection and Affordable Care Act
The Patient Protection and Affordable Care Act, also known as the Affordable Care Act (ACA) or colloquially as Obamacare, is a United States federal statute enacted by the 111th United States Congress and signed into law by President Barack Obama on March 23, 2010. Together with the Health Care and Education Reconciliation Act of 2010 amendment, it represents the U.S. healthcare system's most significant regulatory overhaul and expansion of coverage since the passage of Medicare and Medicaid in 1965. PPACA's major provisions came into force in 2014. By 2016, the uninsured share of the population had roughly halved, with estimates ranging from 20 to 24 million additional people covered. The law also enacted a host of delivery system reforms intended to constrain healthcare costs and improve quality. After the law went into effect, increases in overall healthcare spending slowed, including premiums for employer-based insurance plans. The increased coverage was due, roughly equally, to an expansion of Medicaid eligibility and to changes to individual insurance markets. Both received new spending, funded through a combination of new taxes and cuts to Medicare provider rates and Medicare Advantage. Several Congressional Budget Office reports said that overall these provisions reduced the budget deficit, that repealing PPACA would increase the deficit, and that the law reduced income inequality by taxing primarily the top 1% to fund roughly $600 in benefits on average to families in the bottom 40% of the income distribution. The act largely retained the existing structure of Medicare, Medicaid and the employer market, but individual markets were radically overhauled. Insurers were made to accept all applicants without charging based on pre-existing conditions or demographic status (except age). To combat the resultant adverse selection, the act mandated that individuals buy insurance (or pay a fine/tax) and that insurers cover a list of "essential health benefits". Before and after enactment PPACA faced strong political opposition, calls for repeal and legal challenges. In National Federation of Independent Business v. Sebelius, the Supreme Court ruled that states could choose not to participate in PPACA's Medicaid expansion, although it upheld the law as a whole. The federal health exchange, HealthCare.gov, faced major technical problems at the beginning of its rollout in 2013. Polls initially found that a plurality of Americans opposed the act, although its individual provisions were generally more popular and the law gained majority support by 2017.
  • 4.4K
  • 05 Nov 2022
Topic Review
Commercial Polymeric Membrane for Gas Separation
CO2 has been highly emitted to the environment, with the distribution of 25% being from electricity and heat production, 24% from agriculture, forestry, and other land usages, 21% by industry, 14% from transportation, 10% by other energies, and 6% from building. CO2 removal from natural gas is needed due to issues such as corrosion, catalyst poisoning and its effects on lowering the heating value of fuel. Several mass-transfer technologies can be used for this purpose, namely, membrane, absorption, adsorption and cryogenic. Membrane-based separation methods are more energy-efficient than heat-driven separations. Membrane-based separation uses 90% less energy than its distillation counterpart.
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  • 12 Jan 2022
Topic Review
Hydraulic Accumulators in Hydraulic Systems
Electric motors used in industrial machines and devices, as well as internal combustion engines (ICE) used in vehicles, mobile machines, and marine devices, participate in the transformation of mechanical power into hydraulic power. In power transmission, hydraulic drive systems have a high power density. Hydraulic pumps, as energy sources in hydraulic drive systems, are widely used due to their high working pressure and high flow rate. The hydraulic accumulator (HA) is a device that is used to store energy in the hydraulic system in the form of pressure energy. 
  • 4.4K
  • 14 Sep 2023
Topic Review
The Biological Effects of Retinoids in the Skin
In the early 20th century, retinol (commonly known as vitamin A) was isolated and characterized as an essential nutrient for human health. Retinoids are natural and synthetic vitamin A derivatives that are effective for the prevention and the treatment of non-melanoma skin cancers. The effects of retinoid signaling on skin physiology have been studied extensively.
  • 4.4K
  • 01 Nov 2022
Topic Review
Chemotherapy-Induced Peripheral Neuropathy
Chemotherapy-induced peripheral neuropathy (CIPN) is a common adverse event of several first-line chemotherapeutic agents, including platinum compounds, taxanes, vinca alkaloids, thalidomide, and bortezomib, which negatively affects the quality of life and clinical outcome.
  • 4.4K
  • 22 Feb 2021
Topic Review
Olive orchards under climate change
The olive tree (Olea europaea L.) is an ancient traditional crop in the Mediterranean Basin. In the Mediterranean region, traditional olive orchards are distinguishable by their prevailing climatic conditions. Olive trees are indeed considered one of the most suitable and best-adapted species to the Mediterranean-type climate. However, new challenges are predicted to arise from climate change, threatening this traditional crop. The Mediterranean Basin is considered a climate change “hotspot,” as future projections hint at considerable warming and drying trends. Changes in olive tree suitability have already been reported over the last few decades. In this context, climate change may become particularly challenging for olive growers.
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  • 14 Jan 2021
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.
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  • 13 Apr 2022
Topic Review
Michelia × alba (M. alba)
Michelia × alba (M. alba) is a flowering tree best known for its essential oil, which has long been used as a fragrance ingredient for perfume and cosmetics. 
  • 4.4K
  • 10 Jun 2022
Topic Review
Single-Zone HVAC Systems
Single-zone HVAC systems are installed in most residential buildings, which implies regulating all the rooms of the house with a single thermostat and with static ventilation registers.
  • 4.4K
  • 27 Oct 2020
Topic Review
Mercury's Magnetic Field
Mercury's magnetic field is approximately a magnetic dipole (meaning the field has only two magnetic poles) apparently global, on planet Mercury. Data from Mariner 10 led to its discovery in 1974; the spacecraft measured the field's strength as 1.1% that of Earth's magnetic field. The origin of the magnetic field can be explained by dynamo theory. The magnetic field is strong enough near the bow shock to slow the solar wind, which induces a magnetosphere.
  • 4.4K
  • 15 Nov 2022
Topic Review
Ceramic Materials for Biomedical Applications
The word “biomaterial” refers to a substance or a mix of materials of synthetic or natural origin interacting with biological systems. The main purpose of biomaterials is to support the healing or replacement of an organ in a human body that has been altered by a disease or an accidental event and to successfully restore function and sometimes aesthetic features without endangering human life. Biomaterials can be classified according to their chemical nature as metallic, polymeric, ceramic, and composite, and can also be biologically derived. The term “ceramic” (from the Greek word κεραμικό: “keramikò,” which means “burnt stuff”), a word that is also found in ancient texts, indicates any heat-treated material derived from clayey raw materials through a process called firing. Generally speaking, ceramics are inorganic materials consisting of metallic and non-metallic components chemically bonded together by means of ionic or prevalently ionic bonds with a variable degree of covalent character. 
  • 4.4K
  • 07 Apr 2023
Topic Review
Carbon Fiber Reinforced Polymer
Carbon fiber reinforced polymer (American English), Carbon fibre reinforced polymer (Commonwealth English), or carbon fiber reinforced plastic, or carbon fiber reinforced thermoplastic (CFRP, CRP, CFRTP, or often simply carbon fiber, carbon composite, or even carbon), is an extremely strong and light fiber-reinforced plastic which contains carbon fibers. The spelling 'fibre' is typically used outside the US. CFRPs can be expensive to produce, but are commonly used wherever high strength-to-weight ratio and stiffness (rigidity) are required, such as aerospace, superstructures of ships, automotive, civil engineering, sports equipment, and an increasing number of consumer and technical applications. The binding polymer is often a thermoset resin such as epoxy, but other thermoset or thermoplastic polymers, such as polyester, vinyl ester, or nylon, are sometimes used. The composite material may contain aramid (e.g. Kevlar, Twaron), ultra-high-molecular-weight polyethylene (UHMWPE), aluminium, or glass fibers in addition to carbon fibers. The properties of the final CFRP product can also be affected by the type of additives introduced to the binding matrix (resin). The most common additive is silica, but other additives such as rubber and carbon nanotubes can be used. The material is also referred to as graphite-reinforced polymer or graphite fiber-reinforced polymer (GFRP is less common, as it clashes with glass-(fiber)-reinforced polymer).
  • 4.4K
  • 28 Nov 2022
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