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Topic Review
Anatomy of the Rumen Affecting the Microbiome
The rumen is a complex organ that is critical for its host to convert low-quality feedstuffs into energy. The conversion of lignocellulosic biomass to volatile fatty acids and other end products is primarily driven by the rumen microbiome and its interaction with the host. Importantly, the rumen is demarcated into five distinct rumen sacs as a result of anatomical structure, resulting in variable physiology among the sacs. 
  • 4.4K
  • 23 Mar 2023
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
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.
  • 4.4K
  • 21 Nov 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.
  • 4.4K
  • 21 Jun 2022
Topic Review
Human-Centered Machine Learning
Human-centered Machine Learning (HCML) is about developing adaptable and usable Machine Learning systems for human needs while keeping the human/user at the center of the entire product/service development cycle.
  • 4.4K
  • 06 Oct 2021
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 Peer Reviewed
Benefits of Badminton for Preventing Cognitive Decline and Dementia
Badminton is one of the most popular racket sports played by all age groups worldwide. Anyone can practice and play badminton as a leisure or competitive sport, regardless of age, experience, or skill level. It does not require physical contact among players or expensive equipment. Compared with closed-skill exercises (e.g., running and swimming), open-skill exercises (e.g., badminton and table tennis) have been reported to significantly improve cognitive function and prevent cognitive decline. This mini review aimed to investigate the findings related to badminton intervention for cognitive function, with attention to the modifiable risk factors of dementia in adults. Additionally, we outlined the characteristics of badminton’s physical demands. This narrative review encompassed studies reported from 2013 to 2023 from multiple databases, including PubMed and Google Scholar. Keywords such as “badminton”, “dementia”, “cognitive function”, “physical activity”, and “depression” were used to identify relevant articles. Various studies, including randomized controlled trials, cohort studies, and case–control studies, were selected to provide a comprehensive overview of badminton intervention. Quantitative data analysis suggests that at a cognitive level, high-intensity badminton can enhance cognitive function with at least 10 min of play once weekly or 20 min of play once weekly on average, whereas moderate-intensity badminton can be effective when played for at least 30 min once weekly or 35 min twice weekly on average. For modifiable risk factors, recreational badminton for about 3 h weekly could effectively manage blood pressure. For body fat percentage and fasting serum glucose levels, recreational badminton for about 10 h weekly exerted positive effects. For depressive states, a moderate-intensity badminton program for 100 min weekly was effective. For lipid profiles associated with dementia occurrence, prolonged badminton intervention for more than 3 months may be beneficial. The characteristics presented here indicate that intervention with regular badminton exercise could effectively improve cognitive function and prevent cognitive decline in older adults.
  • 4.4K
  • 18 Jun 2024
Topic Review Peer Reviewed
Bioplastic as a Substitute for Plastic in Construction Industry
Bioplastics have proven to be a viable substitute for plastics in some sectors, although their use in construction is still limited. The construction sector currently uses 23% of the world’s plastic production, both for the materials themselves and for their packaging and protection. A considerable part is not recycled and is dispersed into the environment or ends up in landfills. In response to the environmental problems caused by oil-based plastic pollution, the development of biocomposite materials such as bioplastics represents a paradigm shift. This entry aims to explain what bioplastics are, providing a classification and the description of the different properties and applications. It also lays out the most interesting uses of these materials in the construction field. 
  • 4.4K
  • 02 Aug 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
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
Natural Polymers Used in Edible Food Packaging
Natural polymers like polysaccharides and proteins, i.e., alginate; carrageenan; chitosan; starch; pea protein, are important materials obtained from renewable plant, algae and animal sources, as well as from agroindustrial residues. Historically, some of them have been widely used by ancient populations for food packaging until these were replaced by petroleum-based plastic materials after World War II. Nowadays, biobased materials for food packaging have attracted attention. Their use was boosted especially because of the environmental pollution caused by inappropriate disposal of plastic packaging. Biobased materials are welcome to the design of food packaging because they possess many advantages, such as biodegradability, biocompatibility and low toxicity. Depending on the formulation, certain biopolymer-based packaging may present good barrier properties, antimicrobial and antioxidant activities Thus, polysaccharides and proteins can be combined to form diverse composite films with improved mechanical and biological behaviors, making them suitable for packaging of different food products. 
  • 4.4K
  • 10 Jan 2022
Topic Review
Dry Permanent Magnetic Separator
Dry magnetic separation is a technology that sorts magnetic minerals from gangue using air as the medium instead of water. When raw ore is fed to the magnetic separator, the magnetic particles are subjected to magnetic force due to the nonuniform magnetic field. When the magnetic force exceeds the competitive force (i.e., gravity and fluid drag force), the particles are captured on or attracted towards the surface of the drum and consequently enter the magnetic product. Meanwhile, the gangue or poor intergrowth particles are not subjected to magnetic force and are separated into the non-magnetic product under the action of competitive force. In other words, magnetic minerals and gangue have different trajectories in a magnetic separator, thereby achieving the purpose of separation. Dry magnetic separation has been recently adopted by plants to cope with cost and environmental pressures.
  • 4.4K
  • 24 Oct 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.
  • 4.4K
  • 12 Jan 2022
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
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
Methanol
Methanol, an alcohol with an odor similar to that of ethanol, has been described to exist in low concentrations in the human organism and occurs naturally at a low level in most spirits, without conferring health risk if it exists within the legal limits. 
  • 4.4K
  • 20 Jan 2021
Topic Review
International Harvester Metro Van
International Harvester's Metro Van is a step van, also known as walk-in or multi-stop delivery truck. This vehicle type was one of the earlier, mass-produced forward control vehicles, once commonly used for milk or bakery delivery, as well as ambulance services, mobile offices, and radio transmitter vans. Typically, they were 1/2-, 3/4-, or 1-ton panel trucks that allowed the driver to stand or sit while driving the vehicle. Variations included a passenger bus called a Metro Coach, a Metro partial cab-chassis with front-end sections (for end-user customization), and a cab-over truck called a "walk-in cab". The truck (also called a chassis cab) variation could be configured with a separate box or container for cargo transport or left open to be fitted with other equipment such as a compactor for a garbage truck or a stake bed.
  • 4.4K
  • 05 Dec 2022
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
Topic Review
Major Synthetic Fuels
A concise yet comprehensive overview of major synthetic fuels currently in production worldwide. The fuels are virtually categorised in an intelligible manner with detailed descriptions of their chemical equations, feedstocks, production processes, applications, and global market leaders.
  • 4.4K
  • 27 Mar 2023
Topic Review
Urban Wastewater Treatment in Greece
Although Greece has accomplished the wastewater infrastructure construction in a large extent, as 91% of the country’s population is already connected to urban wastewater treatment plants (WWTPs), many problems still need to be faced, such as the limited reuse of treated wastewater and of the surplus sludge (biosolids) produced, the relative higher energy consumption in the existing rather aged WWTPs infrastructure and the proper management of failing or inadequately designed septic tank/soil absorption systems, still in use in several (mostly rural) areas, lacking sewerage systems. Moreover, the wastewater treatment sector should be examined in the general framework of sustainable environmental development; therefore, Greece’s future challenges in this sector ought to be reconsidered. Thus, the review of Greece’s urban wastewater history, even from the ancient times, up to current developments and trends, will be shortly addressed. Noting also that the remaining challenges should be analyzed in respect to the country’s specific needs (e.g. interaction with the extensive tourism sector), as well as to the European Union’s relevant framework policies and to the respective international technological trends, aiming to consider the wastewater treatment plants (WWTPs) not only as sites for the treatment/removal of pollutants to prevent environmental pollution, but also as industrial places where energy is efficiently used (or even produced), resources’ content can be potentially recovered and reused (e.g. nutrients, treated water, biosolids) and the environmental sustainability is being overall practiced.
  • 4.4K
  • 04 Aug 2020
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