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Topic Review

Fungal Metabolism

Fungi metabolism consists on a series of reactions that results in the biosynthesis of a huge number of compounds. These compounds area usually divided into primary and secondary metabolites. Primary metabolism is common to several species and usually produces compounds with the function of assuring fungi growth and development. Secondary metabolism refers to the production of compounds that are not indispensable during fungi development. Secondary metabolites are commonly referred as "natural products" and have been extensively utilized in the pharmaceutical, cosmetics and food industry. Fungal metabolism is an excellent source of compounds related to the improvement of human health, and a discussion on this application is presented below.

10.0K
18 Nov 2021

Topic Review

Vitamin B6 and Diabetes

Vitamin B6 is an essential nutrient for the human health. It is involved in more that 150 metabolic reactions which regulate the metabolism of glucose, lipids, amino acids, DNA, and neurotransmitters. In addition, vitamin B6 is an antioxidant molecule able to counteracting the formation of reactive oxygen species (ROS) and advanced glycation end-products (AGEs). Epidemiological and experimental studies indicated the reduced levels of vitamin B6 can cause diabetes. In contrast other studies show that diabetes decreases vitamin B6 levels. Thus these findings lead to envisage the existence of a vicious circle at the basis of the relationship between vitamin B6 and diabetes. This entry reports the main evidence concerning the role of vitamin B6 in diabetes and examine the underlying molecular and cellular mechanisms.

10.0K
28 Oct 2020

Topic Review

Barcelona (/ˌbɑːrsəˈloʊnə/ BAR-sə-LOH-nə, Catalan: [bəɾsəˈlonə], Spanish: [baɾθeˈlona]) is a city in Spain . It is the capital and largest city of Catalonia, as well as the second most populous municipality of Spain. With a population of 1.6 million within city limits, its urban area extends to numerous neighbouring municipalities within the Province of Barcelona and is home to around 4.8 million people, making it the sixth most populous urban area in the European Union after Paris, London, Madrid, the Ruhr area and Milan. It is one of the largest metropolises on the Mediterranean Sea, located on the coast between the mouths of the rivers Llobregat and Besòs, and bounded to the west by the Serra de Collserola mountain range, the tallest peak of which is 512 metres (1,680 feet) high. Founded as a Roman city, in the Middle Ages Barcelona became the capital of the County of Barcelona. After merging with the Kingdom of Aragon, Barcelona continued to be an important city in the Crown of Aragon as an economic and administrative centre of this Crown and the capital of the Principality of Catalonia. Barcelona has a rich cultural heritage and is today an important cultural centre and a major tourist destination. Particularly renowned are the architectural works of Antoni Gaudí and Lluís Domènech i Montaner, which have been designated UNESCO World Heritage Sites. The headquarters of the Union for the Mediterranean are located in Barcelona. The city is known for hosting the 1992 Summer Olympics as well as world-class conferences and expositions and also many international sport tournaments. Barcelona is one of the world's leading tourist, economic, trade fair and cultural centres, and its influence in commerce, education, entertainment, media, fashion, science, and the arts all contribute to its status as one of the world's major global cities. It is a major cultural and economic centre in southwestern Europe, 24th in the world (before Zürich, after Frankfurt) and a financial centre. In 2008 it was the fourth most economically powerful city by GDP in the European Union and 35th in the world with GDP amounting to €177 billion. In 2012 Barcelona had a GDP of $170 billion; and it was leading Spain in employment rate in that moment. In 2009 the city was ranked Europe's third and one of the world's most successful as a city brand. In the same year the city was ranked Europe's fourth best city for business and fastest improving European city, with growth improved by 17% per year, and the city has been experiencing strong and renewed growth for the past three years. Since 2011 Barcelona has been a leading smart city in Europe. Barcelona is a transport hub, with the Port of Barcelona being one of Europe's principal seaports and busiest European passenger port, an international airport, Barcelona–El Prat Airport, which handles over 40 million passengers per year, an extensive motorway network, and a high-speed rail line with a link to France and the rest of Europe.

10.0K
16 Nov 2022

Topic Review

In science fiction and in the beliefs of ufology, a Venusian (/vɪˈnjuːʒən, -ʃən/) or Venerian is a native inhabitant of the planet Venus. Many science fiction writers have imagined what extraterrestrial life on Venus might be like.

10.0K
21 Oct 2022

Topic Review

Declaration of War

A declaration of war is a formal act by which one state goes to war against another. The declaration is a performative speech act (or the signing of a document) by an authorized party of a national government, in order to create a state of war between two or more states. The legality of who is competent to declare war varies between nations and forms of government. In many nations, that power is given to the head of state or sovereign. In other cases, something short of a full declaration of war, such as a letter of marque or a covert operation, may authorise war-like acts by privateers or mercenaries. The official international protocol for declaring war was defined in the Hague Convention (III) of 1907 on the Opening of Hostilities. Since 1945, developments in international law such as the United Nations Charter, which prohibits both the threat and the use of force in international conflicts, have made declarations of war largely obsolete in international relations. The UN Security Council, under powers granted in articles 24 and 25, and Chapter VII of the Charter, may authorize collective action to maintain or enforce international peace and security. Article 51 of the United Nations (UN) Charter also states that: "Nothing in the present Charter shall impair the inherent right to individual or collective self-defence if an armed attack occurs against a state." Few nations have formally declared war upon another since then. In addition to this, non-state or terrorist organizations may claim to or be described as "declaring war" when engaging in violent acts. These declarations may have no legal standing in themselves, but they may still act as a call to arms for supporters of these organizations.

10.0K
11 Dec 2025

Topic Review

Supercapacitor Applications and Developments

The storage of enormous energies is a significant challenge for electrical generation. Researchers have studied energy storage methods and increased efficiency for many years. In recent years, researchers have been exploring new materials and techniques to store more significant amounts of energy more efficiently. In particular, renewable energy sources and electric vehicle technologies are triggering these scientific studies. Scientists and manufacturers recently proposed the supercapacitor (SC) as an alternating or hybrid storage device.

10.0K
28 Mar 2022

Topic Review

Extraction Methods for Anthocyanins

Anthocyanins are considered high added-value compounds due to their sensory qualities, colors, and nutritional properties; they are considered bioactive ingredients. They are found in high concentrations in many by-products across the food industry. At present, expensive raw materials and production technologies make the extraction of natural anthocyanins relatively expensive.

10.0K
18 Feb 2022

Topic Review

Ground-Penetrating Radar in Soil Studies

Information on the spatiotemporal variability of soil properties and states within the agricultural landscape is vital to identify management zones supporting precision agriculture (PA). Ground-penetrating radar (GPR) and electromagnetic induction (EMI) techniques have been applied to assess soil properties, states, processes, and their spatiotemporal variability.

9.9K
14 Jun 2023

Topic Review

A company's earnings before interest, taxes, depreciation, and amortization (commonly abbreviated EBITDA, pronounced /iːbɪtˈdɑː/, /əˈbɪtdɑː/, or /ˈɛbɪtdɑː/) is an accounting measure calculated using a company's earnings, before interest expenses, taxes, depreciation, and amortization are subtracted, as a proxy for a company's current operating profitability (i.e., how much profit it makes with its present assets and its operations on the products it produces and sells, as well as providing a proxy for cash flow). Though often shown on an income statement, it is not considered part of the Generally Accepted Accounting Principles (GAAP) by the SEC.

9.9K
08 Oct 2022

Topic Review

Iranian Plateau

The Iranian Plateau or the Persian Plateau is a geological feature in Central Asia, South Asia, and Western Asia. It is the part of the Eurasian Plate wedged between the Arabian and Indian plates, situated between the Zagros Mountains to the west, the Caspian Sea and the Kopet Dag to the north, the Armenian Highlands and the Caucasus Mountains in the northwest, the Strait of Hormuz and the Persian Gulf to the south and the Indo-Gangetic Plain to the east in Indian subcontinent. As a historical region, it includes Parthia, Media, Persis, the heartlands of Iran and some of the previous territories of Greater Iran. The Zagros Mountains form the plateau's western boundary, and its eastern slopes may be included in the term. The Encyclopædia Britannica excludes "lowland Khuzestan" explicitly and characterizes Elam as spanning "the region from the Mesopotamian Plain to the Iranian Plateau". From the Caspian in the northwest to Balochistan in the south-east, the Iranian Plateau extends for close to 2,000 km. It encompasses the greater part of Iran, all of Afghanistan, and Pakistan west of the Indus River containing some 3,700,000 square kilometres (1,400,000 sq mi). In spite of being called a "plateau", it is far from flat but contains several mountain ranges, the highest peak being Damavand in the Alborz at 5610 m, and the Dasht-e Lut east of Kerman in Central Iran falling below 300 m.

9.9K
22 Nov 2022

Topic Review

List of Minerals A (Complete)

This list includes those recognised minerals beginning with the letter A. The International Mineralogical Association is the international group that recognises new minerals and new mineral names, however minerals discovered before 1959 did not go through the official naming procedure, although some minerals published previously have been either confirmed or discredited since that date. This list contains a mixture of mineral names that have been approved since 1959 and those mineral names believed to still refer to valid mineral species (these are called "grandfathered" species). The list is divided into groups: The data was exported from mindat.org on 29 April 2005; updated up to 'IMA2018'. The minerals are sorted by name, followed by the structural group (rruff.info/ima and ima-cnmnc by mineralienatlas.de, mainly) or chemical class (mindat.org and basics), the year of publication (if it's before of an IMA approval procedure), the IMA approval and the Nickel–Strunz code. The first link is to mindat.org, the second link is to webmineral.com, and the third is to the Handbook of Mineralogy (Mineralogical Society of America).

9.9K
05 Dec 2022

Topic Review

IQ and the Wealth of Nations

IQ and the Wealth of Nations is a 2002 book by psychologist Richard Lynn and political scientist Tatu Vanhanen. The authors argue that differences in national income (in the form of per capita gross domestic product) are correlated with differences in the average national intelligence quotient (IQ). They further argue that differences in average national IQs constitute one important factor, but not the only one, contributing to differences in national wealth and rates of economic growth. The book has drawn widespread criticism from other academics. Critiques have included questioning of the methodology used, the incompleteness of the data, and the conclusions drawn from the analysis. The 2006 book IQ and Global Inequality is a follow-up to IQ and the Wealth of Nations by the same authors.

9.9K
14 Oct 2022

Topic Review

Collagen is the major fibrillar protein in most living organisms. Among the different types of collagen, type I collagen is the most abundant one in the tissues of marine invertebrates. The present overview has focused on a brief history of collagen, basic structure and synthesis, nomenclature, types, and classifications, sources of collagen with the emphasis on sea cucumber collagen, and related functional properties.

9.9K
13 Oct 2020

Topic Review

Take This Lollipop

Take This Lollipop is a 2011 interactive horror short film and Facebook app written and directed by Jason Zada. It uses the Facebook Connect application to bring viewers themselves into the film, through use of pictures and messages from their own Facebook profiles. Starring actor Bill Oberst Jr. as 'The Facebook Stalker', the film acts to personalize and underscore the dangers inherent in posting too much personal information about oneself on the internet. The information gathered from a viewer's Facebook profile by the film's app is used once, and then deleted. The title is derived from the 1963 song "Please Little Girl Take This Lollipop", written and performed by singer-songwriter Bobby Jameson, which is used in the film. According to Zada, Take This Lollipop was taken offline "a few months" prior to August 2018. The film's website now hosts a Facebook post by him, saying that the data needed had become "quite hard to access" and had affected the functionality of the film.

9.9K
20 Oct 2022

Topic Review

Lithium Recovery via Chemical Precipitation

Lithium is a vital raw material used for a wide range of applications, such as the fabrication of glass, ceramics, pharmaceuticals, and batteries for electric cars. The accelerating electrification transition and the global commitment to decarbonization have caused an increasing demand for lithium. The current supply derived from brines and hard rock ores is not enough to meet the global demand unless alternate resources and efficient techniques to recover this valuable metal are implemented.

9.9K
21 Feb 2023

Topic Review

The Heritage Foundation

The Heritage Foundation (abbreviated to Heritage) is an American conservative think tank based in Washington, D.C., primarily geared towards public policy. The foundation took a leading role in the conservative movement during the presidency of Ronald Reagan, whose policies were taken from Heritage's policy study Mandate for Leadership. Since then, The Heritage Foundation has continued to have a significant influence in U.S. public policy making, and is considered to be one of the most influential conservative public policy organizations in the United States .

9.9K
07 Nov 2022

Topic Review

ThinkCentre M Series

The M-series of desktops are part of Lenovo's ThinkCentre product line. Formerly an IBM brand, Lenovo acquired the ThinkCentre desktop brand following its purchase of IBM's Personal Computing Division (PCD) in 2005. Following its acquisition of IBM's PCD, Lenovo has released M-series desktops in multiple form factors, ranging from traditional tower, to small form factor, and all-in-ones (AIOs).

9.9K
02 Nov 2022

Topic Review

SpyCatcher-SpyTag System

The SpyCatcher-SpyTag system was developed as a method for protein ligation. It is based on a modified domain from a Streptococcus pyogenes surface protein (SpyCatcher), which recognizes a cognate 13-amino-acid peptide (SpyTag). Upon recognition, the two form a covalent isopeptide bond between the side chains of a lysine in SpyCatcher and an aspartate in SpyTag. This technology has been used, among other applications, to create covalently stabilized multi-protein complexes, for modular vaccine production, and to label proteins (e.g., for microscopy).

9.9K
19 Oct 2022

Topic Review

Methods of Residual Stress Measurement

This entry introduces several commonly used residual stress measurement methods.

9.9K
01 Nov 2020

Topic Review

Sensor Technology in Autonomous Vehicles

With the significant advancement of sensor and communication technology and the reliable application of obstacle detection techniques and algorithms, automated driving is becoming a pivotal technology that can revolutionize the future of transportation and mobility. Sensors are fundamental to the perception of vehicle surroundings in an automated driving system, and the use and performance of multiple integrated sensors can directly determine the safety and feasibility of automated driving vehicles.

9.8K
31 Mar 2021

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