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Topic Review
Pulmonary Artery Catheter
Pulmonary artery catheterization (PAC), or right heart catheterization, is the insertion of a catheter into a pulmonary artery. Its purpose is diagnostic; it is used to detect heart failure or sepsis, monitor therapy, and evaluate the effects of drugs. The pulmonary artery catheter allows direct, simultaneous measurement of pressures in the right atrium, right ventricle, pulmonary artery, and the filling pressure ("wedge" pressure) of the left atrium. The pulmonary artery catheter is frequently referred to as a Swan-Ganz catheter, in honor of its inventors Jeremy Swan and William Ganz, from Cedars-Sinai Medical Center.
  • 5.3K
  • 24 Nov 2022
Topic Review
Odor Compounds in Meat
The volatile composition and odor of meat and meat products is based on the precursors present in the raw meat. These are influenced by various pre-slaughter factors (species, breed, sex, age, feed, muscle type). Furthermore, post-mortem conditions (chiller aging, cooking conditions, curing, fermentation, etc.) determine the development of meat volatile organic compounds (VOCs).
  • 5.3K
  • 08 Nov 2022
Topic Review
Democratic Deficit in the European Union
The notion of a democratic deficit within the European Union (EU) is the idea that the governance of the EU lacks democratic legitimacy. This led in part to an elected European Parliament being created in 1979 and given the power to approve or reject EU legislation. Since then, usage of the term has broadened to describe newer issues facing the European Union. However voter turnout has fallen consecutively at the seven elections since the first election in 1979 and voter turnout in the 2014 election stood at 42.54% of all European voters. This is the lowest of any national election in the 28 countries of the European Union where turnout at national elections averages 68% across the EU. Opinions differ as to whether the EU has a democratic deficit or how it should be remedied if it exists. Pro-Europeans (i.e. those in favour of the EU) argue that the European Union should reform its institutions to make them more accountable, while Eurosceptics argue that the EU should reduce its powers and often campaign for withdrawal from the EU.
  • 5.3K
  • 23 Nov 2022
Topic Review
Spilled Oil in Marine Environment
Oil spill is a widespread environmental problem with significant ecological impacts. When oil is spilled in the sea,  it undergoes different  degradation processes such as dispersion, photooxidation, evaporation, dissolution, emulsion, biodegradation and other weathering processes. The most important among these processes is biodegradation, which is facilitated by naturally occurring oil-degrading bacteria.  The interaction of bacteria with hydrocarbons in oil is affected by different environmental factors.  Several studies have evaluated the effects of each factor on the biodegradation of the oil by bacterial, but none has taken all these factors together.
  • 5.3K
  • 06 Apr 2022
Topic Review
Fashion Influencer
A fashion influencer is a personality that has a large number of followers on social media, creates mainly fashion content and has the power to influence the opinion and purchase behavior of others with their recommendations. Brands endorse them to attend fashion shows, parties, designer dinners and exclusive trips and to wear their clothes on social media. If a salary has been involved, the influencer may be required to label such posts as paid or sponsored content. Before social media "they would have been called 'It girls'". Business magazine Forbes identified fashion influencers as "the new celebrity endorsements". However, influencers seem to have a closer relationship with their audience than traditional celebrities. As marketers Jung von Matt, Brandnew IO and Facelift point out: "Daily interactions across multiple channels, through photos, stories or live sessions, create a form of closeness and trust" that make influencers "often more tangible than traditional celebrities".
  • 5.3K
  • 20 Oct 2022
Topic Review
Organizational Silos
Organizational silos are herein defined and contextualized from a behavioral perspective. Specifically, silos are not only seen as barriers to communication and information flow, but they are analyzed in terms of their consequences on organizational structure, process and function. This three-tier division drawn from the literature on complex systems and networks is next adapted to fit a framework of behavior in organizations, which is a function of its environmental consequences. As learning may occur, the concept of silos can be informed by complexity theory, findings from cognitive-behavioral sciences, and a socio-cultural perspective. Moreover, the role of clusters are discussed in light of the aforementioned approaches to silos in organizations.
  • 5.3K
  • 27 Oct 2020
Topic Review
Diamond DA40
The Diamond DA40 Star is an Austrian four-seat, single-engine, light aircraft constructed from composite materials. Built in both Austria and Canada, it was developed as a four-seat version of the earlier DA20 by Diamond Aircraft Industries.
  • 5.3K
  • 04 Nov 2022
Topic Review
Irritator
Irritator is a genus of spinosaurid dinosaur that lived in what is now Brazil during the Albian stage of the Early Cretaceous Period, about 113 to 110 million years ago. It is known from a nearly complete skull found in the Romualdo Formation of the Araripe Basin. Fossil dealers had acquired this skull and sold it to the State Museum of Natural History Stuttgart. In 1996, the specimen became the holotype of the type species Irritator challengeri. The genus name comes from the word "irritation", reflecting the feelings of paleontologists who found the skull had been heavily damaged and altered by the collectors. The species name is a homage to the fictional character Professor Challenger from Arthur Conan Doyle's novels. Some paleontologists regard Angaturama limai—known from a snout tip that was described later in 1996—as a potential junior synonym of Irritator. Both animals hail from the same stratigraphic units of the Araripe Basin. It was also previously proposed that Irritator and Angaturama's skull parts belonged to the same specimen. Although this has been cast into doubt, more overlapping fossil material is needed to confirm whether they are the same animal or not. Other spinosaurid skeletal material, some of which could belong to Irritator or Angaturama, was retrieved from the Romualdo Formation, allowing for a replica skeleton to be made and mounted for display at the National Museum of Rio de Janeiro in 2009. Estimated at between 6 and 8 meters (20 and 26 ft) in length, Irritator weighed around 1 tonne (1.1 short tons), making it one of the smallest spinosaurids known. Its long, shallow and slender snout was lined with straight and unserrated conical teeth. Lengthwise atop the head ran a thin sagittal crest, to which powerful neck muscles were likely anchored. The nostrils were positioned far back from the tip of the snout, and a rigid secondary palate on the roof of the mouth would have strengthened the jaw when feeding. Belonging to a subadult, Irritator challengeri's holotype remains the most completely preserved spinosaurid skull yet found. The Angaturama snout tip expanded to the sides in a rosette-like shape, bearing long teeth and an unusually tall crest. One possible skeleton indicates it, like other spinosaurids, had enlarged first-finger claws and a sail running down its back. Irritator had been mistaken initially for a pterosaur, and later a maniraptoran dinosaur. In 1996, the animal was identified as a spinosaurid theropod. The holotype skull was thoroughly prepared before being redescribed in 2002, confirming this classification. Both Irritator and Angaturama belong to the Spinosaurinae subfamily. A generalist diet—like that of today's crocodilians—has been suggested; Irritator might have preyed mainly on fish and any other small prey animals it could catch. Fossil evidence is known of an individual that ate a pterosaur, either from hunting or scavenging it. Irritator may have had semiaquatic habits, and inhabited the tropical environment of a coastal lagoon surrounded by dry regions. It coexisted with other carnivorous theropods as well as turtles, crocodyliforms, and a large number of pterosaur and fish species.
  • 5.3K
  • 03 Nov 2022
Topic Review
List of Minerals L (Complete)
This list includes those recognised minerals beginning with the letter L. 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).
  • 5.3K
  • 05 Nov 2022
Topic Review
Southeast Asian Diet
There is a significant degree of dietary diversity across and within the various Southeast Asian countries. This is due to a myriad of factors such as a degree of past and present foreign influence, a history of maritime trade, and an abundance of local ingredients available in the region. Social stratification coupled with the many distinct ethnicities, cultures, religions further complicate meal practices by impacting the choice of foods, the structure of meals, as well as the patterns of eating behaviour. This level of variability can make it difficult for consumption patterns to be accurately defined and may reduce the effectiveness of population-wide nutrition surveillance.
  • 5.3K
  • 30 Oct 2020
Topic Review
Preconsolidation Pressure
Preconsolidation pressure is the maximum effective vertical overburden stress that a particular soil sample has sustained in the past. This quantity is important in geotechnical engineering, particularly for finding the expected settlement of foundations and embankments. Alternative names for the preconsolidation pressure are preconsolidation stress, pre-compression stress, pre-compaction stress, and preload stress. A soil is called overconsolidated if the current effective stress acting on the soil is less than the historical maximum. The preconsolidation pressure can help determine the largest overburden pressure that can be exerted on a soil without irrecoverable volume change. This type of volume change is important for understanding shrinkage behavior, crack and structure formation and resistance to shearing stresses. Previous stresses and other changes in a soil's history are preserved within the soil's structure. If a soil is loaded beyond this point the soil is unable to sustain the increased load and the structure will break down. This breakdown can cause a number of different things depending on the type of soil and its geologic history. Preconsolidation pressure cannot be measured directly, but can be estimated using a number of different strategies. Samples taken from the field are subjected to a variety of tests, like the constant rate of strain test (CRS) or the incremental loading test (IL). These tests can be costly due to expensive equipment and the long period of time they require. Each sample must be undisturbed and can only undergo one test with satisfactory results. It is important to execute these tests precisely to ensure an accurate resulting plot. There are various methods for determining the preconsolidation pressure from lab data. The data is usually arranged on a semilog plot of the effective stress (frequently represented as σ'vc) versus the void ratio. This graph is commonly called the e log p curve or the consolidation curve.
  • 5.3K
  • 17 Oct 2022
Topic Review
Paraprobiotics
Paraprobiotics are defined as “inactivated microbial cells (non-viable) that confer a health benefit to the consumer” and hold the ability to regulate the adaptive and innate immune systems, to exhibit anti-inflammatory, antiproliferative and antioxidant properties, and to exert antagonistic effect against pathogens, thus confirming that viability of probiotics is not an absolute pre-requisite for promoting health effects. 
  • 5.3K
  • 05 May 2021
Topic Review
Love Bombing
Love bombing is an attempt to influence a person by demonstrations of attention and affection. It can be used in different ways and for either positive or negative purposes. Psychologists have identified love bombing as a possible part of a cycle of abuse and have warned against it. Critics of cults use the phrase with the implication that the "love" is feigned and that the practice is psychological manipulation in order to create a feeling of unity within the group against a society perceived as hostile. In 2011 clinical psychologist Oliver James advocated love bombing in his book Love Bombing: Reset Your Child's Emotional Thermostat, as a means for parents to rectify emotional problems in their children.
  • 5.3K
  • 20 Oct 2022
Topic Review
Panopticon
The Panopticon is a type of institutional building and a system of control designed by the English philosopher and social theorist Jeremy Bentham in the late 18th century. The scheme of the design is to allow all (pan-) inmates of an institution to be observed (-opticon) by a single watchman without the inmates being able to tell whether or not they are being watched. Although it is physically impossible for the single watchman to observe all the inmates' cells at once, the fact that the inmates cannot know when they are being watched means that they are motivated to act as though they are being watched at all times. Thus, they are effectively compelled to regulate their own behaviour. The name may also allude to the many-eyed giant Panoptes in Greek mythology, some of whose eyes were always awake, making him a highly effective watchman. The design consists of a circular structure with an "inspection house" at its centre, from which the manager or staff of the institution is able to watch the inmates. The inmates, who are stationed around the perimeter of the structure, are unable to see into the inspection house. Bentham conceived the basic plan as being equally applicable to hospitals, schools, sanatoriums, and asylums, but he devoted most of his efforts to developing a design for a Panopticon prison. It is his prison that is now most widely meant by the term "panopticon". Bentham described the Panopticon as "a new mode of obtaining power of mind over mind, in a quantity hitherto without example". Elsewhere, in a letter, he described the Panopticon prison as "a mill for grinding rogues honest".
  • 5.3K
  • 24 Nov 2022
Topic Review Peer Reviewed
Main Carotenoids Produced by Microorganisms
Carotenoids are the pigments present in plants, animals, and microorganisms which are responsible for a broad variety of colors found in nature. Their capacity as antioxidants mainly established their marketable success as health, food, and feed supplements, and cosmetics components. Currently, chemical synthesis dominates the worldwide market; however, due to the high biological value of natural carotenoids, the production scheme is moving towards microbial production as a profitable alternative. 
  • 5.3K
  • 13 Apr 2022
Topic Review
Management Accounting Practices in the Hospitality Industry
The tourism and hospitality industries are key to the economies of many countries, and governments are interested in these sectors because of their multiplier effect. Management accounting allows the control, the anticipation of problems, and the opening up of perspectives in companies; this tool is very powerful in preparing accounting information to improve the company’s costs, revenues, and results.
  • 5.3K
  • 18 Feb 2022
Topic Review
Synergism (Theology)
In Christian theology, synergism is the position of those who hold that salvation involves some form of cooperation between divine grace and human freedom. It stands opposed to monergism, a doctrine most commonly associated with the Lutheran and Reformed Protestant traditions, whose soteriologies have been strongly influenced by the North African bishop and Latin Church Father Augustine of Hippo (354–430). Lutheranism, however, confesses a monergist salvation and synergist damnation (see below). Synergism is upheld by the Orthodox and Roman Catholic Churches, and by the Methodist and Pentecostal traditions of Protestantism. It is an integral part of Arminian theology. Synergism and semipelagianism each teach some collaboration in salvation between God and man, but semipelagian thought teaches that the beginning half of faith is an act of human will. The Council of Orange (529), Lutheran Formula of Concord (1577), and other local councils each condemned semipelagianism as heresy.
  • 5.3K
  • 24 Nov 2022
Topic Review
Extracellular Matrix and Its Artificial Substitutes
The existence of orderly structures such as tissues and organs is made possible by cell adhesion, i.e. the process by which cells attach to neighbouring cells and a supporting substance in the form of the extracellular matrix. The extracellular matrix is a three-dimensional structure composed of collagens, elastin and various proteoglycans and glycoproteins. It is a storehouse for multiple signalling factors. Tissue disruption often prevents the natural reconstitution of the matrix. The use of appropriate implants is then required. The possibilities of regenerating damaged tissues using an artificial matrix substitute are described, detailing the host response to the implant. An important issue is the surface properties of such an implant and the possibilities of their modification.
  • 5.3K
  • 25 Mar 2022
Topic Review
Cancer Biomarkers
Cancer is one of the major public health issues in the world. It has become the second leading cause of death, with approximately 75% of cancer deaths transpiring in low- or middle-income countries. It causes a heavy global economic cost estimated at more than a trillion dollars per year. The conventional diagnostic technologies such as MRI (magnetic resonance imaging), CT (computerized tomography) scan, ultrasound and biopsy were not effective for cancer detection at primary stages; this is because of their dependency on tumorigenic properties or phenotypic characters of a tumor. Cancer is a very complex disease, with many epigenetic as well as genetic modifications which might alter the cell signaling process, related to development and resulting in tumorigenic transformation and malignancy. For almost all cancer patients, researchers and clinicians expect tests or methods that might diagnose cancer significantly earlier, provide better prognosis, and that can allow for increased survival rates. Cancer markers have been used in the oncology field. Biomarkers are molecules of biologic emergence found in blood, tissues, various body fluids such as urine, cerebrospinal fluid, or different body tissues that are elevated is the indicative of an abnormal disease or condition with cancer. 
  • 5.3K
  • 24 Mar 2023
Topic Review
Carbonatite-Related REE Deposits
The rare earth elements (REEs) have unique and diverse properties that make them function as an “industrial vitamin” and thus, many countries consider them as strategically important resources. China, responsible for more than 60% of the world’s REE production, is one of the REE‐rich countries in the world. Most REE (especially light rare earth elements (LREE)) deposits are closely related to carbonatite in China. Such a type of deposit may also contain appreciable amounts of industrially critical metals, such as Nb, Th and Sc. According to the genesis, the carbonatite‐related REE deposits can be divided into three types: primary magmatic type, hydrothermal type and carbonatite weathering‐crust type. This paper provides an overview of the carbonatite‐related endogenetic REE deposits, i.e., primary magmatic type and hydrothermal type. The carbonatite‐related endogenetic REE deposits are mainly distributed in continental margin depression or rift belts, e.g., Bayan Obo REE‐Nb‐Fe deposit, and orogenic belts on the margin of craton such as the Miaoya Nb‐REE deposit. The genesis of carbonatite‐related endogenetic REE deposits is still debated. It is generally believed that the carbonatite magma is originated from the low‐degree partial melting of the mantle. During the evolution process, the carbonatite rocks or dykes rich in REE were formed through the immiscibility of carbonate-silicate magma and fractional crystallization of carbonate minerals from carbonatite magma. The ore‐forming elements are mainly sourced from primitive mantle, with possible contribution of crustal materials that carry a large amount of REE. In the magmatic-hydrothermal system, REEs migrate in the form of complexes, and precipitate corresponding to changes of temperature, pressure, pH and composition of the fluids. A simple magmatic evolution process cannot ensure massive enrichment of REE to economic values. Fractional crystallization of carbonate minerals and immiscibility of melts and hydrothermal fluids in the hydrothermal evolution stage play an important role in upgrading the REE mineralization. Future work of experimental petrology will be fundamental to understand the partitioning behaviors of REE in magmatic-hydrothermal system through simulation of the metallogenic geological environment. Applying “comparative metallogeny” methods to investigate both REE fertile and barren carbonatites will enhance the understanding of factors controlling the fertility.
  • 5.3K
  • 17 Nov 2020
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