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Topic Review
Cup Lump Natural Rubber
Cup lump is obtained when fresh latex is extracted by tapping into a long cut made in a rubber tree and letting the drips pour into a plastic cup.
  • 7.1K
  • 05 May 2023
Topic Review
Alaria alata
Alaria alata flukes are cosmopolitan parasites. In Europe, the definitive hosts are red foxes (Vulpes vulpes), wolves (Canis lupus), and raccoon dogs (Nyctereutes procyonoides), as well as animals that belong to the Felidae family. Intermediate hosts, such as snails and frogs, are the sources of infection for definitive hosts. The developmental stages of A. alata mesocercariae may occur in paratenic hosts, including many species of mammals, birds, and reptiles, as well as in wild boars (Sus scrofa), which are important from the zoonotic point of view. Alaria alata is a widespread trematode that is considered a potential cause of a human disease called alariosis, which is associated with the consumption of raw or undercooked meat of intermediate or paratenic hosts of this parasite.
  • 7.0K
  • 11 Aug 2021
Topic Review
Solubility of Oxygen and Hydrogen in Water
Produced by photosynthesis, oxygen (O2) is a fundamentally important gas in biological systems, playing roles as a terminal electron receptor in respiration and in host defence through the creation of reactive oxygen species (ROS). Hydrogen (H2) plays a role in metabolism for some organisms, such as at thermal vents and in the gut environment, but has a role in controlling growth and development, and in disease states, both in plants and animals.
  • 7.0K
  • 28 Feb 2024
Topic Review
History of the Euro
The euro came into existence on 1 January 1999, although it had been a goal of the European Union (EU) and its predecessors since the 1960s. After tough negotiations, particularly due to opposition from the United Kingdom, the Maastricht Treaty entered into force in 1993 with the goal of creating an economic and monetary union by 1999 for all EU states except the UK and Denmark (even though Denmark has a fixed exchange rate policy with the euro). In 1999 the currency was born virtually and in 2002 notes and coins began to circulate. It rapidly took over from the former national currencies and slowly expanded behind the rest of the EU. In 2009 the Lisbon Treaty finalised its political authority, the Eurogroup, alongside the European Central Bank.
  • 7.0K
  • 29 Nov 2022
Topic Review
E-Book
An electronic book, also known as an e-book or eBook, is a book publication made available in digital form, consisting of text, images, or both, readable on the flat-panel display of computers or other electronic devices. Although sometimes defined as "an electronic version of a printed book", some e-books exist without a printed equivalent. E-books can be read on dedicated e-reader devices, but also on any computer device that features a controllable viewing screen, including desktop computers, laptops, tablets and smartphones. In the 2000s, there was a trend of print and e-book sales moving to the Internet, where readers buy traditional paper books and e-books on websites using e-commerce systems. With print books, readers are increasingly browsing through images of the covers of books on publisher or bookstore websites and selecting and ordering titles online; the paper books are then delivered to the reader by mail or another delivery service. With e-books, users can browse through titles online, and then when they select and order titles, the e-book can be sent to them online or the user can download the e-book. By the early 2010s, e-books had begun to overtake hardcover by overall publication figures in the U.S. The main reasons for people buying e-books are possibly lower prices, increased comfort (as they can buy from home or on the go with mobile devices) and a larger selection of titles. With e-books, "[e]lectronic bookmarks make referencing easier, and e-book readers may allow the user to annotate pages." "Although fiction and non-fiction books come in e-book formats, technical material is especially suited for e-book delivery because it can be [electronically] searched" for keywords. In addition, for programming books, code examples can be copied. The amount of e-book reading is increasing in the U.S.; by 2014, 28% of adults had read an e-book, compared to 23% in 2013. This is increasing, because by 2014 50% of American adults had an e-reader or a tablet, compared to 30% owning such devices in 2013.
  • 7.0K
  • 30 Sep 2022
Topic Review
Biblical Cosmology
Biblical cosmology is the biblical writers' conception of the cosmos as an organised, structured entity, including its origin, order, meaning and destiny. The Bible was formed over many centuries, involving many authors, and reflects shifting patterns of religious belief; consequently, its cosmology is not always consistent. Nor do the biblical texts necessarily represent the beliefs of all Jews or Christians at the time they were put into writing: the majority of those making up Hebrew Bible or Old Testament in particular represent the beliefs of only a small segment of the ancient Israelite community, the members of a late Judean religious tradition centered in Jerusalem and devoted to the exclusive worship of Yahweh. The ancient Israelites envisaged a universe made up of a flat disc-shaped Earth floating on water, heaven above, underworld below. Humans inhabited Earth during life and the underworld after death; there was no way that mortals could enter heaven, and the underworld was morally neutral; only in Hellenistic times (after c. 330 BCE) did Jews begin to adopt the Greek idea that it would be a place of punishment for misdeeds, and that the righteous would enjoy an afterlife in heaven. In this period too the older three-level cosmology in large measure gave way to the Greek concept of a spherical earth suspended in space at the center of a number of concentric heavens. The opening words of the Genesis creation narrative (Genesis 1:1–26) sum up the biblical editors' view of how the cosmos originated: "In the beginning God created the heavens and the earth"; Yahweh, the God of Israel, was solely responsible for creation and had no rivals, implying Israel's superiority over all other nations. Later Jewish thinkers, adopting ideas from Greek philosophy, concluded that God's Wisdom, Word and Spirit penetrated all things and gave them unity. Christianity in turn adopted these ideas and identified Jesus with the Logos (Word): "In the beginning was the Word, and the Word was with God, and the Word was God" (John 1).
  • 7.0K
  • 11 Jan 2024
Topic Review
Geodetic Datum
A geodetic datum or geodetic system (also: geodetic reference datum or geodetic reference system) is a coordinate system, and a set of reference points, used for locating places on the Earth (or similar objects). An approximate definition of sea level is the datum WGS 84, an ellipsoid, whereas a more accurate definition is Earth Gravitational Model 2008 (EGM2008), using at least 2,159 spherical harmonics. Other datums are defined for other areas or at other times; ED50 was defined in 1950 over Europe and differs from WGS 84 by a few hundred meters depending on where in Europe you look. Mars has no oceans and so no sea level, but at least two martian datums have been used to locate places there. Datums are used in geodesy, navigation, and surveying by cartographers and satellite navigation systems to translate positions indicated on maps (paper or digital) to their real position on Earth. Each starts with an ellipsoid (stretched sphere), and then defines latitude, longitude and altitude coordinates. One or more locations on the Earth's surface are chosen as anchor "base-points". The difference in co-ordinates between datums is commonly referred to as datum shift. The datum shift between two particular datums can vary from one place to another within one country or region, and can be anything from zero to hundreds of meters (or several kilometers for some remote islands). The North Pole, South Pole and Equator will be in different positions on different datums, so True North will be slightly different. Different datums use different interpolations for the precise shape and size of the Earth (reference ellipsoids). Because the Earth is an imperfect ellipsoid, localised datums can give a more accurate representation of the area of coverage than WGS 84. OSGB36, for example, is a better approximation to the geoid covering the British Isles than the global WGS 84 ellipsoid. However, as the benefits of a global system outweigh the greater accuracy, the global WGS 84 datum is becoming increasingly adopted. Horizontal datums are used for describing a point on the Earth's surface, in latitude and longitude or another coordinate system. Vertical datums measure elevations or depths.
  • 7.0K
  • 24 Nov 2022
Topic Review
Minkowski Diagram
The Minkowski diagram, also known as a spacetime diagram, was developed in 1908 by Hermann Minkowski and provides an illustration of the properties of space and time in the special theory of relativity. It allows a qualitative understanding of the corresponding phenomena like time dilation and length contraction without mathematical equations. Minkowski diagrams are two-dimensional graphs that depict events as happening in a universe consisting of one space dimension and one time dimension. Unlike a regular distance-time graph, the distance is displayed on the horizontal axis and time on the vertical axis. Additionally, the time and space units of measurement are chosen in such a way that an object moving at the speed of light is depicted as following a 45° angle to the diagram's axes. In this way, each object, like an observer or a vehicle, traces a certain line in the diagram, which is called its world line. Also, each point in the diagram represents a certain position in space and time, and is called an event, regardless of whether anything relevant happens there and then.
  • 7.0K
  • 10 Oct 2022
Topic Review
Bush Encroachment
Bush encroachment (also shrub encroachment, woody encroachment, bush thickening, woody plant proliferation) is a natural phenomenon characterised by the increase in density of woody plants, bushes and shrubs, at the expense of the herbaceous layer, grasses and forbs. It predominantly occurs in grasslands, savannas and woodlands and can cause biome shifts from open grasslands and savannas to closed woodlands. The term bush encroachment refers to the expansion of native plants and not the spread of alien invasive species. It is thus defined by plant density, not species. Bush encroachment is often considered an ecological regime shift and can be a symptom of land degradation. Its causes include land use intensification, such as high grazing pressure and the suppression of wildfires. Climate change is found to be an accelerating factor for woody encroachment. The impact of bush encroachment is highly context specific. It is often found to have severe negative consequences on key ecosystem services, especially biodiversity, animal habitat, land productivity and groundwater recharge. Across rangelands, woody encroachment has led to significant declines of productivity, threatening the livelihoods of affected land users. The phenomenon is observed across different ecosystems and with different characteristics and intensities globally. Various countries actively counter woody encroachment, through adapted grassland management practices and targeted bush thinning. In some cases, areas affected by woody encroachment are classified as carbon sinks and form part of national greenhouse gas inventories. However, carbon sequestration effects of woody encroachment are highly context specific and still insufficiently researched.
  • 7.0K
  • 08 Nov 2022
Topic Review
Polish Pension System
Polish’s Pension System was reformed in 1999. The new system is built from three parts. It comprises a public pension and an earnings-related system with notional accounts.  There are also voluntary employer sponsored pension plans.
  • 7.0K
  • 02 Nov 2020
Topic Review
IPTV
Internet Protocol television (IPTV) is the delivery of television content over Internet Protocol (IP) networks. This is in contrast to delivery through traditional terrestrial, satellite, and cable television formats. Unlike downloaded media, IPTV offers the ability to stream the source media continuously. As a result, a client media player can begin playing the content (such as a TV channel) almost immediately. This is known as streaming media. Although IPTV uses the Internet protocol it is not limited to television streamed from the Internet, (Internet television). IPTV is widely deployed in subscriber-based telecommunications networks with high-speed access channels into end-user premises via set-top boxes or other customer-premises equipment. IPTV is also used for media delivery around corporate and private networks. IPTV in the telecommunications arena is notable for its ongoing standardisation process (e.g., European Telecommunications Standards Institute). IPTV services may be classified into three main groups:  Live television and live media, with or without related interactivity; Time-shifted media: e.g. catch-up TV (replays a TV show that was broadcast hours or days ago), start-over TV (replays the current TV show from its beginning); Video on demand (VOD): browse and view items in a stored media catalogue.
  • 7.0K
  • 27 Oct 2022
Topic Review
Bitching Betty
Bitching Betty is a slang term used by some pilots and aircrew (mainly North American), when referring to the voices used by some aircraft warning systems. The enunciating voice, in at least some aircraft systems, may be either male or female and in some cases this may be selected according to pilot preference. If the voice is female, it may be referred to as Bitching Betty; if the voice is male, it may be referred to as Barking Bob. A female voice is heard on military aircraft such as the F-16 Fighting Falcon, the Eurofighter Typhoon and the Mikoyan MiG-29. A male voice is heard on Boeing commercial airliners and is also used in the BAE Hawk. In the United Kingdom the term Nagging Nora is sometimes used, and in New Zealand the term used for Boeing aircraft is Hank the Yank. The voice warning system used on London Underground trains, which also uses a female voice, is known to some staff as Sonya, as it "gets on ya nerves".
  • 7.0K
  • 11 Oct 2022
Topic Review
Smart Grid Management, Control, and Operation
Smart grid management, control and operation (SGMCO) are key tasks for maintaining their proper functioning as well as for their extension and expansion. The current challenges of power generation, distribution, transmission, and consumption, as well as growing energy demand, facilitate the integration of a large number of smart grids with renewable energy generators and physical information systems, while smart grids are moving toward distribution and decentralization in response to the evolving application of the Internet of Energy (IoE). SGMCO handles not only traditional management, control, and operations, but also the future challenges for smart grids: Collaboration between stakeholders, control of network imbalances (e.g. frequency and voltage regulation), data analysis and management, decentralized network management and operation, and security and privacy.
  • 7.0K
  • 10 Jan 2022
Topic Review
West African Lion
The West African lion is a Panthera leo leo population in West Africa. It is listed as Critically Endangered on the IUCN Red List. This population is isolated and probably comprises fewer than 250 mature individuals. Already in 2004, the lion population in West and Central Africa was fragmented and estimated as comprising at most 1,800 individuals. The West African lion was formerly considered a distinct lion subspecies with the scientific name P. l. senegalensis. Results of phylogenetic research indicate that the West African lion population forms a distinct clade and is closely related to Central African, North African and Asian lion populations. The lion populations in North, West and Central Africa and Asia were therefore subsumed to P. l. leo in 2017.
  • 7.0K
  • 17 Oct 2022
Topic Review
Production of Electrolytic Manganese Dioxide
The ferromanganese (FeMn) alloy is produced through the smelting-reduction of manganese ores in submerged arc furnaces. This process generates large amounts of furnace dust that is environmentally problematic for storage. Due to its fineness and high volatile content, this furnace dust cannot be recirculated through the process, either. Conventional MnO2 production requires the pre-reduction of low-grade ores at around 900 °C to convert the manganese oxides present in the ore into their respective acid-soluble forms; however, the furnace dust is a partly reduced by-product. A hydrometallurgical route is proposed to valorize the waste dust for the production of battery-grade MnO2. By using dextrin, a cheap organic reductant, the direct and complete dissolution of the manganese in the furnace dust is possible without any need for high-temperature pre-reduction. The leachate is then purified through pH adjustment followed by direct electrowinning for electrolytic manganese dioxide (EMD) production. An overall manganese recovery rate of >90% is achieved. 
  • 7.0K
  • 08 Jul 2021
Topic Review
University Social Responsibility
University Social Responsibility (USR) enhances educational development and the impact of universities on society. As a stakeholder in USR, it is imperative to develop a comprehensive literacy scale that reflects the development of students’ citizenship in social engagement.
  • 7.0K
  • 26 Apr 2022
Topic Review
Food Marketing
It would seem important to analyse the relationships between food marketing and consumer choice, highlighting the role of brands in these frameworks. For this purpose, a literature review was carried out considering 147 documents from Scopus database for the topics of search “food marketing” and“choices” (search performed on 16 October 2020). As main insights, it is worth highlighting that the main issues addressed by the literature, concerning food marketing and consumer choices, are the following: economic theory; label and packaging; marketing strategies; agriculture and food industry; market segments; social dimensions; brand and branding. In turn, food marketing heavily conditions consumer choices; however, these related instruments are better manipulated by larger companies. In addition, this entry highlights that bigger companies have dominant positions in these markets which are not always beneficial to the consumers’ objectives.
  • 7.0K
  • 07 May 2021
Topic Review
List of Largest Stars
Below is a list of the largest stars currently known, ordered by radius. The unit of measurement used is the radius of the Sun (approximately 695,700 km; 432,300 mi). The angular diameters of stars can be measured directly using stellar interferometry. Other methods can use lunar occultations or from eclipsing binaries, which can be used to test indirect methods of finding stellar radii. Only a few useful supergiant stars can be occulted by the Moon, including Antares A (Alpha Scorpii A). Examples of eclipsing binaries are Epsilon Aurigae (Almaaz), VV Cephei, and V766 Centauri (HR 5171). Angular diameter measurements can be inconsistent because the boundary of the very tenuous atmosphere (opacity) differs depending on the wavelength of light in which the star is observed. Uncertainties remain with the membership and order of the list, especially when deriving various parameters used in calculations, such as stellar luminosity and effective temperature. Often stellar radii can only be expressed as an average or be within a large range of values. Values for stellar radii vary significantly in different sources and for different observation methods. All the sizes stated in this list have various inaccuracies and may be disputed. This list is still a work in progress and various parameters are extremely disputed.
  • 7.0K
  • 21 Nov 2022
Topic Review
Micro-Electromechanical Systems Vibrating Gyroscopes
Micro-electromechanical systems (MEMS) vibrating gyroscopes have gained a lot of attention because of their low power consumption, easy integration, and low fabrication cost. The usage of the gyroscope equipped with an inertial measurement unit has increased tremendously, with applications ranging from household devices to smart electronics to military equipment. However, reliability issues are still a concern when operating this inertial sensor in harsh environments, such as to control the movement and alignment of mini-satellites in space, tracking firefighters at an elevated temperature, and assisting aircraft navigation in gusty turbulent air. 
  • 7.0K
  • 18 Oct 2022
Topic Review
Conifers Phytochemicals
The phytochemical constituents present in conifer extracts are nontoxic at therapeutic levels, with polyphenolic compounds having significant biological activities. Stilbenes, terpenes, alkaloids, lignins and flavanoids, such as quercetin, rutin, resveratrol, and the compounds PYC and enzogenol, are the phytochemical components of conifer extracts reported to have sedative, antidiabetic, anticancer and anesthetic effects. In addition, phytochemicals present in conifer extracts assist in the regulation of glucose and lipid metabolism, insulin secretion, stimulating β cells, the NF-kB signaling pathway, the inhibition of gluconeogenic enzymes, ROS protective action as well as targeting and modulating cytokines which affect neuron cells and reduce oxidative stress.
  • 7.0K
  • 01 Jun 2021
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