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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.
  • 5.1K
  • 03 Nov 2022
Topic Review
Toxicological Risks of the Cobalt–Chromium Alloys in Dentistry
Cobalt–chromium (Co-Cr) alloys have been used for a long period of time in dentistry, but several risk factors remain involved. The toxicological risk of Co-Cr dental alloys is actually a sensitive subject with the European regulatory changes, namely regulation (EU) 2017/745 and annex VI to the CLP regulation (EC) 1972/2008. Studies assessing Co-Cr dental alloys’ biocompatibility are urgently needed.
  • 5.1K
  • 22 Feb 2023
Topic Review
Aquaculture Food Production in Portugal
World aquaculture food production rises every year, amounting, by 2018, to another all-time record of 82.1 million tonnes of farmed seafood, with Asia leading global production. In Europe, although coastal countries present historical fishing habits, aquaculture is in true expansion. Norway, the leading European producer, is the eighth main producer worldwide. Portugal is a traditional fishing country but has invested in the development of aquaculture for the past decade, attaining, by 2018, 13.3 tonnes produced, making Portugal the 16th main producer amongst European Union member states that year. Most Portuguese aquaculture facilities operate in coastal systems, resorting to extensive and semi-intensive rearing techniques. In Portugal, marine food production in transitional systems is particularly interesting as the practice has, worldwide, been continuously substituted by intensive methods. In fact, facilities in transitional systems have developed over time and products gained higher commercial value.
  • 5.1K
  • 18 Mar 2022
Topic Review
Christian
A Christian (/ˈkrɪstʃən, -tiən/ (listen)) is a person who follows or adheres to Christianity, an Abrahamic, monotheistic religion based on the life and teachings of Jesus Christ. "Christian" derives from the Koine Greek word Christós (Χριστός), a translation of the Biblical Hebrew term mashiach (Biblical Hebrew: מָשִׁיחַ). While there are diverse interpretations of Christianity which sometimes conflict, they are united in believing that Jesus has a unique significance. The term "Christian" is also used as an adjective to describe anything associated with Christianity, or in a proverbial sense "all that is noble, and good, and Christ-like." According to a 2011 Pew Research Center survey, there were 2.2 billion Christians around the world in 2010, up from about 600 million in 1910. By 2050, the Christian population is expected to exceed 3 billion. According to a 2012 Pew Research Center survey Christianity will remain the world's largest religion in 2050, if current trends continue. Today, about 37% of all Christians live in the Americas, about 26% live in Europe, 24% live in sub-Saharan Africa, about 13% live in Asia and the Pacific, and 1% live in the Middle East and North Africa. About half of all Christians worldwide are Catholic, while more than a third are Protestant (37%). Orthodox communions comprise 12% of the world's Christians. Other Christian groups make up the remainder. Christians make up the majority of the population in 158 countries and territories. 280 million Christians live as a minority. Christians have significantly influenced and contributed to human progress in many fields including philanthropy, philosophy,:15 ethics, literature, business and economics, fine arts and architecture, music, theatre and medicine, as well as science and technology, both historically and in modern times.
  • 5.1K
  • 27 Oct 2022
Topic Review
Mangrove Forest Functions and Services
Mangroves stand out as one of the most diverse and biologically significant natural systems in the world. Playing critical roles in maintaining the health and productivity of coastal ecosystems, mangroves provide a range of services and functions, including habitat for local fauna and flora, food and other goods, carbon sequestration, and protection from natural disasters such as storm surges and coastal erosion. 
  • 5.1K
  • 12 Sep 2023
Topic Review
Sheep Meat Processed Products
A concise review of the origin and type of the most important sheep and goat processed meat products produced in different countries and world regions is made. The manuscript also summarizes the most recent studies on sheep and goat processed meats on the physicochemical characterizations, sensory quality, microbiological quality and safety. Some conclusions and future trends in production, processing and commercial potentiality for sheep and goat processed meat products are discussed.
  • 5.1K
  • 06 Dec 2023
Topic Review
Apple Bioactive Compounds
Population studies have associated a diet high in fruits to lower incidence of cancer. Specifically, research shows that secondary plant metabolites known as phytochemicals, which are commonly found in fruits, have onco-preventive and chemo-protective effects. Apple is a commonly consumed fruit worldwide that is available all year round and is a rich source of phytochemicals. The health benefits of apples are thought to be mainly due to their phytochemical composition. Additionally, apple consumption is associated with lower incidence of some cancers based on animal and cell culture studies.
  • 5.1K
  • 30 Nov 2021
Topic Review
The State of Drinking Water in Kazakhstan
Kazakhstan has rich drinking water resources, but its uneven distribution and quality is an acute problem that needs to be solved. This article presents the current state of drinking water in the country, especially in its northern region - Akmola region, as based on statistical data, it has the worst indicators of drinking water and the reasons for such values are clarified. The only solution to this situation is a complete modernization of the water supply system through strict control of design and estimate documentation and proper planning of construction.
  • 5.1K
  • 02 Sep 2025
Topic Review
BM-30 Smerch
The BM-30 Smerch (Russian: Смерч, "tornado", "whirlwind"), 9K58 Smerch or 9A52-2 Smerch-M is a Soviet heavy multiple rocket launcher. The system is intended to defeat personnel, armored, and soft targets in concentration areas, artillery batteries, command posts and ammunition depots. It was designed in the early 1980s and entered service in the Soviet Army in 1989. When first observed by the West in 1983, it received the code MRL 280mm M1983. It is expected to be superseded by the 9A52-4 Tornado.
  • 5.1K
  • 15 Nov 2022
Topic Review
Honey and Atherosclerosis
Honey, a natural sweetener has been used universally as a complete food and in complementary medicine since early antiquity. Honey contains over 180 substances, including sugars mainly fructose and glucose, water and a plethora of minor constituents such as vitamins, minerals and phytochemicals.  Atherosclerosis is a chronic disease occurring in the inner lining of arterial walls due to the progressive plaque formation. Multiple risk factors are implicated in the pathogenesis of atherosclerosis, including oxidative stress, inflammatory responses, hypercholesterolemia, hypertension, diabetes and cigarette smoking.
  • 5.1K
  • 29 Oct 2021
Topic Review
Blading (Professional Wrestling)
In professional wrestling, blading is the practice of intentionally cutting oneself to provoke bleeding. It is also known as "juicing", "gigging", or "getting color". Similarly, a blade is an object used for blading and a bladejob is a specific act of blading. The act is usually done a good length into the match as the blood will mix with the flowing sweat to make it look like much more blood is flowing from the wound than there actually is. The preferred area for blading is usually the forehead, as scalp wounds bleed profusely and heal easily. Legitimate, unplanned bleeding which occurs outside the storyline is called "juicing the hard way".
  • 5.1K
  • 24 Oct 2022
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.
  • 5.1K
  • 24 Nov 2022
Topic Review
Traditional Healing Practices in Fiji
Traditional Healing Practices in Fiji means the therapies using ceremonies; plant-, animal-, or mineral-based medicines; energy therapies (also called biofield therapies). They are based on the belief that there are energy fields that flow through and around your body. When energy is flowing freely through your body, you have good emotional, physical and spiritual health. When you are ill, the energy flow is blocked 
  • 5.1K
  • 28 Sep 2021
Topic Review
Teleparallel Equivalent of General Relativity
The teleparallel equivalent of general relativity (TEGR) is an alternative geometrical formulation of the relativistic theory of gravitation. A brief description of the  TEGR is presented. The building blocks of the theory and few main achievements are discussed.
  • 5.1K
  • 30 Oct 2020
Topic Review
List of Selected Stars for Navigation
Fifty-eight selected navigational stars are given a special status in the field of celestial navigation. Of the approximately 6,000 stars visible to the naked eye under optimal conditions, the selected stars are among the brightest and span 38 constellations of the celestial sphere from the declination of −70° to +89°. Many of the selected stars were named in antiquity by the Babylonians, Greeks, Romans, and Arabs. The star Polaris, often called the "North Star", is treated specially due to its proximity to the north celestial pole. When navigating in the Northern Hemisphere, special techniques can be used with Polaris to determine latitude or gyrocompass error. The other 57 selected stars have daily positions given in nautical almanacs, aiding the navigator in efficiently performing observations on them. A second group of 115 "tabulated stars" can also be used for celestial navigation, but are often less familiar to the navigator and require extra calculations. For purposes of identification, the positions of navigational stars — expressed as declination and sidereal hour angle — are often rounded to the nearest degree. In addition to tables, star charts provide an aid to the navigator in identifying the navigational stars, showing constellations, relative positions, and brightness.
  • 5.1K
  • 26 Oct 2022
Topic Review
Health Effects of 8-Prenylnaringenin
8-Prenylnaringenin is a natural compound biosynthesised in the lupulin glands of the hop inflorescences. It is the substance with the highest estrogenic activity known so far in the plant kingdom. As estrogens have many targets in animals and humans, the health effects of 8-prenylnaringenin can be either beneficial or adverse depending on the physiological status of the consumers.
  • 5.1K
  • 08 Feb 2023
Topic Review
Borderland
The word “borderland” has many meanings; however, it is most often considered from the geographical and sociological, or, in other words, spatial and cultural perspective. The borderland is an area or a territory located near the border or far away from the centre. Within the borderland, socio-cultural contact takes place between various nations or ethnic groups. This is where the “new people and their culture” are formed. A borderland is sometimes precisely delimited, e.g., based on natural objects such as rivers or mountain ranges, or on administrative attributes. It is, however, most frequently determined on the basis of settlement geography. Its actual area and range are determined by migrations, colonisation, and cultural diversity of its inhabitants .
  • 5.0K
  • 19 Jul 2021
Topic Review
Closed Graph
In mathematics, particularly in functional analysis and topology, closed graph is a property of functions. A function f : X → Y between topological spaces has a closed graph if its graph is a closed subset of the product space X × Y. A related property is open graph. This property is studied because there are many theorems, known as closed graph theorems, giving conditions under which a function with a closed graph is necessarily continuous. One particularly well-known class of closed graph theorems are the closed graph theorems in functional analysis.
  • 5.0K
  • 18 Oct 2022
Topic Review
Purification of Biodiesel Glycerol from Waste Oils
To facilitate the glycerol purification, it is important to know the composition of glycerol from the biodiesel obtained from waste oils and how these oils and the type of biodiesel synthesis influence the glycerol composition. First, different glycerol impurities were studied based on the oil origin and the used catalysts. Thus, the glycerol impurities are detailed to show their influence on the glycerol or on its transformation in other products. Different glycerol characterization techniques were used to determine the purity level and properties of glycerol. The main interest of this part is to describe different methods to purify glycerol and to understand its composition and its utilization.
  • 5.0K
  • 20 May 2022
Topic Review
Internal Monologue
An internal monologue, also called self-talk, inner speech, inner discourse or internal discourse, is a person's inner voice which provides a running verbal monologue of thoughts while they are conscious. It is usually tied to a person's sense of self. It is particularly important in planning, problem solving, self-reflection, self-image, critical thinking, emotions, and subvocalization (reading in one's head). As a result, it is relevant to a number of mental disorders, such as depression, and treatments like cognitive behavioural therapy which seek to alleviate symptoms by providing strategies to regulate cognitive behaviour. It may reflect both conscious and subconscious beliefs. In some cases people may think of inner speech as coming from an external source, as with schizophrenic auditory hallucinations. Additionally, not everyone has a verbal internal monologue (see § Absence of an internal monologue). The looser flow of thoughts and experiences, verbal or not, is called a stream of consciousness, which can also refer to a related technique in literature. In a theory of child development formulated by Lev Vygotsky, inner speech has a precursor in private speech (talking to oneself) at a young age.
  • 5.0K
  • 15 Nov 2022
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