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Topic Review
Patent Foramen Ovale
A patent foramen ovale (PFO) is a commonly discovered potential opening between the right atrium (RA) and left atrium (LA) on routine echocardiographic surveillance in an otherwise asymptomatic infant or child. The importance of a PFO in some critical congenital heart defects (CHD), especially in neonates, is well recognized. 
  • 3.3K
  • 24 Apr 2022
Topic Review
Cell
The cell (from the Latin word cellula meaning 'small room') is the basic structural and functional unit of life forms. Every cell consists of a cytoplasm enclosed within a membrane, which contains many biomolecules such as proteins and nucleic acids. Cells can acquire specified function and carry out various tasks within the cell such as replication, DNA repair, protein synthesis, and motility. Cells are capable of specialization and mobility within the cell. Most cells are measured in micrometers due to their small size. Most plant and animal cells are only visible under a light microscope, with dimensions between 1 and 100 micrometres. Electron microscopy gives a much higher resolution showing greatly detailed cell structure. Organisms can be classified as unicellular (consisting of a single cell such as bacteria) or multicellular (including plants and animals). Most unicellular organisms are classed as microorganisms. The number of cells in plants and animals varies from species to species; it has been approximated that the human body contains an estimated 37 trillion (3.72×1013) cells. The brain accounts for around 80 billion of these cells. The study of cells and how they work has led to many other studies in related areas of biology, including: discovery of DNA, cancer systems biology, aging and developmental biology. Cell biology is the study of cells, which were discovered by Robert Hooke in 1665, who named them for their resemblance to cells inhabited by Christian monks in a monastery. Cell theory, first developed in 1839 by Matthias Jakob Schleiden and Theodor Schwann, states that all organisms are composed of one or more cells, that cells are the fundamental unit of structure and function in all living organisms, and that all cells come from pre-existing cells. Cells emerged on Earth about 4 billion years ago.
  • 3.3K
  • 23 Nov 2022
Topic Review
Zinc and Dog Food
Zinc is an essential trace element, required for enzymatic, structural, and regulatory functions. As body reserves are scarce, an adequate zinc status relies on proper dietary supply and efficient homeostasis. Several biomarkers have been proposed that enable the detection of poor zinc status, but more sensitive and specific ones are needed to detect marginal deficiencies. The zinc content of commercial dry dog foods has great variability, with a more frequent non-compliance with the maximum authorized limit than with the nutritional requirement. The bioavailability of dietary zinc also plays a crucial role in ensuring an adequate zinc status. 
  • 3.3K
  • 21 Apr 2021
Topic Review
Vehicles Exhaust Particulate Matter Emissions
In the automotive field the term “particulate matter (PM)” is used for the collected matter on a flow-through filter under specific conditions, and the term “particle” for aerosol particles measured while airborne (suspended matter). Particles are divided into “volatile” and “non-volatile” (or solid) at tailpipe conditions (high temperature, high concentration). Species that at tailpipe conditions appear volatile, may partition toward the particulate phase at atmospheric conditions (low temperature), and the term semi-volatile better characterizes them. The term “semi-volatiles” (instead of “volatiles”) will be used loosely in this text to indicate species not counted after dilution and thermal pre-treatment at 300–400 °C. The term ultrafine particles (i.e., particles < 100 nm) is not so common in the automotive community. Even though the majority of particles has sizes <100 nm, the tail extends to larger sizes. A recent review argued that a better definition for ultrafine particles (focusing on the automotive field) would be particles <500 nm.
  • 3.3K
  • 09 Feb 2022
Topic Review
A Bioinformatics Workflow of Metabolomics Analysis
Metabolomics is an emerging field that quantifies numerous metabolites systematically. The key purpose of metabolomics is to identify the metabolites corresponding to each biological phenotype, and then provide an analysis of the mechanisms involved. Although metabolomics is important to understand the involved biological phenomena, the approach’s ability to obtain an exhaustive description of the processes is limited. Thus, an analysis-integrated metabolomics, transcriptomics, proteomics, and other omics approach is recommended. Such integration of different omics data requires specialized statistical and bioinformatics software. 
  • 3.3K
  • 25 May 2022
Topic Review
Water on Mars
To assess Mars’ potential for both harboring life and providing useable resources for future human exploration, it is of paramount importance to comprehend the water situation on the planet. Therefore, studies have been conducted to determine any evidence of past or present water existence on Mars. While the presence of abundant water on Mars very early in its history is widely accepted, on its modern form, only a fraction of this water can be found, as either ice or locked into the structure of Mars’ plentiful water-rich materials. Water on the planet is evaluated through various evidence such as rocks and minerals, Martian achondrites, low volume transient briny outflows (e.g., dune flows, reactivated gullies, slope streaks, etc.), diurnal shallow soil moisture (e.g., measurements by Curiosity and Phoenix Lander), geomorphic representation (possibly from lakes and river valleys), and groundwater, along with further evidence obtained by probe and rover discoveries. One of the most significant lines of evidence is for an ancient streambed in Gale Crater, implying ancient amounts of “vigorous” water on Mars. Long ago, hospitable conditions for microbial life existed on the surface of Mars, as it was likely periodically wet. However, its current dry surface makes it almost impossible as an appropriate environment for living organisms; therefore, scientists have recognized the planet’s subsurface environments as the best potential locations for exploring life on Mars. As a result, modern research has aimed towards discovering underground water, leading to the discovery of a large amount of underground ice in 2016 by NASA, and a subglacial lake in 2018 by Italian scientists. Nevertheless, the presence of life in Mars’ history is still an open question. In this unifying context, the current review summarizes results from a wide variety of studies and reports related to the history of water on Mars, as well as any related discussions on the possibility of living organisms' existence on the planet.
  • 3.3K
  • 06 Feb 2022
Topic Review
MALDI–TOF Mass Spectrometry in Microbiology
Mass spectrometry (MS) is an analytical technique that has emerged as a powerful tool in clinical microbiology for identifying peptides and proteins, which makes it a promising tool for microbial identification. Matrix assisted laser desorption ionization–time of flight MS (MALDI–TOF MS) offers a cost- and time-effective alternative to conventional methods, such as bacterial culture and even 16S rRNA gene sequencing, for identifying viruses, bacteria and fungi and detecting virulence factors and mechanisms of resistance. 
  • 3.3K
  • 24 Nov 2021
Topic Review
Adhesion in Bitumen/Aggregate System
The five main theories describing the interaction mechanisms in the bitumen/aggregate system was conducted: theory of weak boundary layers, mechanical theory, electrostatic theory, chemical bonding theory, and thermodynamic theory (adsorption theory). The adhesion assessment methods in the bitumen/aggregate system are described, which can be divided into three main groups: determination of adhesion forces for bitumen with different materials, determination of bitumen resistance to the exfoliating action of water with different materials, and determination of adhesion as a fundamental value (contact angle measurements, interfacial fracture energy, adsorption capacity and others).
  • 3.3K
  • 04 Jan 2023
Topic Review Peer Reviewed
Brazilian Urban Policy: Sustainability as a Driving Force
Defining global themes such as Urban Policy, Urban Sustainability, and even the Right to the City (RTTC) is fundamental to stimulating and establishing a continuous dialogue with the scientific community, mainly in the social sciences. Thus, understanding the dynamics around the scope of urban sustainability requires an analysis that is focused on multiple global realities. Taking a holistic view of Brazilian Urban Policy, this entry looks at the historical contexts that make urban sustainability the driving force behind this policy. In addition, an interdisciplinary consideration of urban sustainability is proposed using an analysis that is based on the connection between urban policies and social functions that reflect the idea of a sustainable city. The results of this analysis also point to the need for a continuous debate on the subject that primarily promotes new discoveries; this is so that the driving force of urban policy can gain new meanings and new guidelines can be implemented.
  • 3.3K
  • 23 May 2023
Topic Review
Automatic Crop Harvesting
Agriculture 4.0 is transforming farming livelihoods thanks to the development and adoption of technologies such as artificial intelligence, the Internet of Things and robotics, traditionally used in other productive sectors. Soft robotics and soft grippers in particular are promising approaches to lead to new solutions in this field due to the need to meet hygiene and manipulation requirements in unstructured environments and in operation with delicate products. Soft grippers are those end-effectors that use materials and actuation methods that are soft, flexible and compliant and that enable the holding of an object to be manipulated. In this context, soft technologies can be defined as the set of theories, techniques and procedures that enable key functions of soft robotic grippers, such as actuation, gripping and shape control methods.
  • 3.3K
  • 28 Apr 2021
Topic Review
Radicalism (Historical)
Radicalism (from Latin radix, "root") was a historical political movement within liberalism during the late 18th and early 19th centuries and a precursor to social liberalism. Its identified radicals were proponents of democratic reform in what subsequently became the parliamentary Radicals in the United Kingdom. During the 19th century in the United Kingdom, continental Europe and Latin America, the term radical came to denote a progressive liberal ideology inspired by the French Revolution . Historically, radicalism emerged in an early form with the French Revolution and the similar movements it inspired in other countries. It grew prominent during the 1830s in the United Kingdom with the Chartists and Belgium with the Revolution of 1830, then across Europe in the 1840s–1850s during the Revolutions of 1848. In contrast to the social conservatism of existing liberal politics, radicalism sought political support for a radical reform of the electoral system to widen suffrage. It was also associated with republicanism, liberalism, left-wing politics, modernism, secular humanism, anti-militarism, civic nationalism, abolition of titles, rationalism and the resistance to a single established state religion, redistribution of property and freedom of the press. In 19th-century France, radicalism had emerged as a minor political force by the 1840s as the extreme left of the day (in contrast to the socially-conservative liberalism of the Moderate Republicans and Orléanist monarchists and the anti-parliamentarianism of the Legitimist monarchists and Bonapartists). By the 1890s, the French radicals were not organised under a single nationwide structure, but rather they had become a significant political force in parliament. In 1901, they consolidated their efforts by forming the country's first major extra-parliamentary political party, the Republican, Radical and Radical-Socialist Party which became the most important party of government during the second half (1899 to 1940) of the French Third Republic. The success of the French Radicals encouraged radicals elsewhere to organise themselves into formal parties in a range of other countries in the late 19th and early 20th century, with radicals holding significant political office in Bulgaria, Denmark, Germany, Greece, Ireland, Italy, Netherlands, Portugal, Romania, Russia, Spain, Sweden and Switzerland. During the interwar period, European radical parties organised the Radical Entente, their own political international. As social democracy emerged as a distinct political force in its own right, the differences that once existed between historical left-wing radicalism and conservative liberalism diminished. Between 1940 and 1973, radicalism became defunct in most of its European heartlands, with its role and philosophy taken on by social-democratic and conservative-liberal parties.
  • 3.3K
  • 01 Dec 2022
Topic Review
Green Customer Value
Green Customer Value means the attitude of customers towards green products has effects on their green purchase intention. The green customer's perceived value, including environmental value and perceived environmental image, have significant and positive influences on attitude towards the green product. 
  • 3.3K
  • 27 Oct 2020
Topic Review
Externalizing Disorders
Externalizing disorders (or externalising disorders) are mental disorders characterized by externalizing behaviors, maladaptive behaviors directed toward an individual's environment, which cause impairment or interference in life functioning. In contrast to individuals with internalizing disorders who internalize (keep inside) their maladaptive emotions and cognitions, such feelings and thoughts are externalized (manifested outside) in behavior in individuals with externalizing disorders. Externalizing disorders are often specifically referred to as disruptive behavior disorders (attention-deficit/hyperactivity disorder, oppositional defiant disorder, and conduct disorder) or conduct problems which occur in childhood. Externalizing disorders, however, are also manifested in adulthood. For example, alcohol- and substance-related disorders and antisocial personality disorder are adult externalizing disorders. Externalizing psychopathology is associated with antisocial behavior, which is different from and often confused for asociality.
  • 3.3K
  • 25 Oct 2022
Topic Review
Surfactants in Corrosion Inhibitors
Surfactants are commonly used as corrosion inhibitors due to their ability to adsorb onto metal surfaces and form a protective barrier. When surfactants are added to a solution, they can reduce the surface tension and promote the wetting of the metal surface by the solution. This allows the surfactant molecules to be attracted to the metal surface, where they can adsorb and form a protective layer. Surfactants can also help to inhibit corrosion by reducing the electrochemical activity of the metal surface. This can be achieved by either reducing the rate of anodic or cathodic reactions, or by reducing the rate of ion transport across the metal-solution interface. By inhibiting these electrochemical processes, the surfactant can slow down the rate of corrosion and prevent further degradation of the metal surface. In addition to their inhibitive properties, surfactants can also improve the performance of other corrosion inhibitors. For example, surfactants can enhance the adsorption of organic inhibitors onto metal surfaces, which can increase their effectiveness. Surfactants can also improve the solubility and stability of inorganic inhibitors, which can improve their dispersibility in a solution.
  • 3.3K
  • 24 Mar 2023
Topic Review
Using of Glycerol in the Esterification of Rosin
Rosin is a compound that originates from pine trees. It is obtained after the volatile component (turpentine) has been distilled. Rosin is translucent and its color ranges from brilliant yellow to brown. The substance exhibits insolubility in water but is soluble in a variety of organic solvents including alcohol, ether, acetone, benzene, chloroform, turpentine, and others. Gum rosin is an important agricultural commodity which is widely used as a raw material for various industries. However, gum rosin has low stability, crystallizes easily, and tends to oxidize. This is due to carboxyl groups and conjugated double bonds in gum rosin’s structure. Therefore, to reduce these weaknesses, it is necessary to modify the rosin compound to achieve better stability via the esterification process.
  • 3.3K
  • 23 Nov 2023
Topic Review
Great Disappointment
The Great Disappointment in the Millerite movement was the reaction that followed Baptist preacher William Miller's proclamations that Jesus Christ would return to the Earth by 1844, what he called the Advent. His study of the Daniel 8 prophecy during the Second Great Awakening led him to the conclusion that Daniel's "cleansing of the sanctuary" was cleansing of the world from sin when Christ would come, and he and many others prepared, but October 22, 1844 came, and they were disappointed. These events paved the way for the Adventists who formed the Seventh-day Adventist Church. They contended that what had happened on October 22 was not Jesus' return, as Miller had thought, but the start of Jesus' final work of atonement, the cleansing in the heavenly sanctuary, leading up to the Second Coming.
  • 3.3K
  • 10 Nov 2022
Topic Review
Sex Education
Sexual education can be defined as any combination of learning experiences aimed at facilitating voluntary behavior conducive to sexual health. Sex education during adolescence has centered on the delivery of content (abstinence-only vs. comprehensive instruction) by teachers, parents, health professionals or community educators, and on the context (within school and beyond) of such deliver.
  • 3.3K
  • 01 Apr 2021
Topic Review
Radio-Absorbing Materials and Technologies for Their Production
Radio waves cover a fairly wide spectrum of the frequency range (the range of waves used is from ultra-long to millimeter; the range is from centimeters and meters to thousands of kilometers) and are harmonic signals modulated in amplitude and frequency. The main source of powerful electromagnetic radiation is an antenna that radiates a flow of electromagnetic energy in a directionally or non-directionally into the surrounding space.
  • 3.3K
  • 17 Aug 2022
Topic Review
Major Pathological Hallmarks of Multiple Sclerosis
Multiple Sclerosis (MS) is a chronic autoimmune disease affecting the central nervous system which is characterized by demyelinating lesions and axonal damage. MS is a complex disease characterized by important pathophysiological heterogeneity affecting the clinical appearance, progression and therapeutic response for each patient. Therefore, there is a strong unmet need to define specific biomarkers that will reflect the different features of the disease. Experimental autoimmune encephalomyelitis (EAE) is the most commonly used experimental model for the study of MS, as it resembles the pathological features of human MS in many aspects and has allowed for the elucidation of pathogenesis pathways and the validation of certain targets for MS therapies. 
  • 3.3K
  • 18 Oct 2022
Topic Review
Middle Mongol Language
Middle Mongol or Middle Mongolian was a Mongolic koiné language spoken in the Mongol Empire. Originating from Genghis Khan's home region of northeastern Mongolia, it diversified into several Mongolic languages after the collapse of the empire. In comparison to Modern Mongolian, it is known to have had no long vowels, different vowel harmony and verbal systems and a slightly different case system.
  • 3.3K
  • 03 Nov 2022
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