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Topic Review
Rhinovirus
Rhinoviruses (RVs) are non-enveloped positive sense RNA viruses with a lifecycle fully contained within the cytoplasm. Despite decades of study, the details of how RVs exit the infected cell are still unclear. Current literature strongly suggests a role for necroptosis and/or autophagy in RV release, with the caveat that all the literature is based on RV-A and RV-B strains, with no studies to date examining the interaction of RV-C strains with cell death pathways.
  • 4.2K
  • 15 Jun 2021
Topic Review
The Relationship between Empathy and Attachment
Empathy is an important channel for health improvement and social adaptation of individuals, laying a foundation for moral development and positive outcomes. A high level of empathy can promote prosocial behavior and the well-being of people while upgrading interpersonal relationships. In contrast, a low level of empathy is closely related with the externalization of aggressive behavior and social adjustment.
  • 4.2K
  • 17 Feb 2022
Topic Review
Superoxide Radical Anion O2•−
Classically, superoxide anion O2•− and reactive oxygen species ROS play a dual role. At the physiological balance level, they are a by-product of O2 reduction, necessary for cell signalling, and at the pathological level they are considered harmful, as they can induce disease and apoptosis, necrosis, ferroptosis, pyroptosis and autophagic cell death.
  • 4.2K
  • 31 Jan 2023
Topic Review
Haze in Beer
Beer is one of the oldest and also most widely consumed alcoholic beverages. It is a kind of colloid solution with complex composition and weak stability. The haze formation in beer is a serious quality problem, as it primarily affects the shelf life and flavor of beer. Hazes are caused by suspended insoluble particles of colloidal or larger size that can be perceived visually or by instruments.
  • 4.2K
  • 06 Jan 2022
Topic Review
Thienopyrimidine
Thienopyrimidine emerges as an attractive scaffold in medicinal chemistry with a wide array of pharmacological properties, such as antibacterial, antifungal, antiparasitic and antiviral. Considering the fusion between pyrimidine and thiophene rings, three different thienopyrimidines can be obtained, namely thieno[2,3-d]pyrimidines, thieno[3,2-d]pyrimidines and thieno[3,4-d]pyrimidines. Different synthetic pathways involving the construction of the pyrimidine or the thiophene ring were reported in the literature to access polysubstituted thienopyrimidines. In these approaches, the synthetic strategies mostly involved the synthesis of a thienopyrimidin-4-one derivative, where position 4 could be modified via further functionalization.
  • 4.2K
  • 13 Jan 2022
Topic Review
Operation Bertram
Operation Bertram was a Second World War deception operation practised by the Allied forces in Egypt led by Bernard Montgomery, in the months before the Second Battle of El Alamein in 1942. Bertram was devised by Dudley Clarke to deceive Erwin Rommel about the timing and location of the Allied attack. The operation consisted of physical deceptions using dummies and camouflage, designed and made by the British Middle East Command Camouflage Directorate led by Geoffrey Barkas. These were accompanied by electromagnetic deceptions codenamed Operation Canwell, using false radio traffic. All of these were planned to make the Axis believe that the attack would take place to the south, far from the coast road and railway, about two days later than the real attack. Bertram consisted of the creation of the appearance of army units where none existed and in concealing armour, artillery and matériel. Dummy tanks and guns were made mainly of local materials including calico and palm-frond hurdles. Real tanks were disguised as trucks, using light "Sunshield" canopies. Field guns and their limbers were also disguised as trucks, their real wheels visible, under a simple box-shaped "Cannibal" canopy to give the shape of a truck. Petrol cans were stacked along the sides of existing revetted trenches, hidden in the shadows. Food was stacked in piles of boxes and draped with camouflage nets to resemble trucks. Trucks were parked openly in the tank assembly area for some weeks. Real tanks were similarly parked openly, far behind the front. Two nights before the attack, the tanks replaced the trucks, being covered with "Sunshields" before dawn. The tanks were replaced that same night with dummies in their original positions, so the armour remained seemingly two or more days' journey behind the front line. To reinforce the impression that the attack was not ready, a dummy water pipeline was constructed, at an apparent rate of 5 mi (8.0 km) per day. Some days' worth remained to be built at the time of the attack; dummy tanks, guns and supplies were constructed to the south. After the battle, the captured German panzerarmee general Wilhelm Ritter von Thoma told Montgomery that he had believed the Allies had at least one more armoured division than they did and that the attack would be in the south. Rommel's stand-in, general Georg Stumme, thought the attack would not begin for several weeks. Bertram had succeeded; when announcing the victory at El Alamein in the House of Commons, Winston Churchill praised the camouflage operation.
  • 4.2K
  • 02 Nov 2022
Topic Review
Earwax
Earwax, also known by the medical term cerumen, is a brown, orange, red, yellowish or gray waxy substance secreted in the ear canal of humans and other mammals. It protects the skin of the human ear canal, assists in cleaning and lubrication, and provides protection against bacteria, fungi, and water. Earwax consists of dead skin cells, hair, and the secretions of cerumen by the ceruminous and sebaceous glands of the outer ear canal. Major components of earwax are long chain fatty acids, both saturated and unsaturated, alcohols, squalene, and cholesterol. Excess or compacted cerumen is the buildup of ear wax causing a blockage in the ear canal and it can press against the eardrum or block the outside ear canal or hearing aids, potentially causing hearing loss.
  • 4.2K
  • 07 Nov 2022
Topic Review
Stuttering
Stuttering, also known as stammering, is a speech disorder in which the flow of speech is disrupted by involuntary repetitions and prolongations of sounds, syllables, words, or phrases as well as involuntary silent pauses or blocks in which the person who stutters is unable to produce sounds. The term stuttering is most commonly associated with involuntary sound repetition, but it also encompasses the abnormal hesitation or pausing before speech, referred to by people who stutter as blocks, and the prolongation of certain sounds, usually vowels or semivowels. According to Watkins et al., stuttering is a disorder of "selection, initiation, and execution of motor sequences necessary for fluent speech production". For many people who stutter, repetition is the main concern. The term "stuttering" covers a wide range of severity, from barely perceptible impediments that are largely cosmetic to severe symptoms that effectively prevent oral communication. Almost 70 million people worldwide stutter, about 1% of the world's population. The impact of stuttering on a person's functioning and emotional state can be severe. This may include fears of having to enunciate specific vowels or consonants, fears of being caught stuttering in social situations, self-imposed isolation, anxiety, stress, shame, low self-esteem, being a possible target of bullying (especially in children), having to use word substitution and rearrange words in a sentence to hide stuttering, or a feeling of "loss of control" during speech. Stuttering is sometimes popularly seen as a symptom of anxiety, but there is no direct correlation in that direction. Stuttering is generally not a problem with the physical production of speech sounds or putting thoughts into words. Acute nervousness and stress are not thought to cause stuttering, but they can trigger stuttering in people who have the speech disorder, and living with a stigmatized disability can result in anxiety and high allostatic stress load (chronic nervousness and stress) that reduce the amount of acute stress necessary to trigger stuttering in any given person who stutters, worsening the situation in the manner of a positive feedback system; the name 'stuttered speech syndrome' has been proposed for this condition. Neither acute nor chronic stress, however, itself creates any predisposition to stuttering. The disorder is also variable, which means that in certain situations, such as talking on the telephone or in a large group, the stuttering might be more severe or less, depending on whether or not the person who stutters is self-conscious about their stuttering. People who stutter often find that their stuttering fluctuates and that they have "good" days, "bad" days and "stutter-free" days. The times in which their stuttering fluctuates can be random. Although the exact etiology, or cause, of stuttering is unknown, both genetics and neurophysiology are thought to contribute. There are many treatments and speech therapy techniques available that may help decrease speech disfluency in some people who stutter to the point where an untrained ear cannot identify a problem; however, there is essentially no cure for the disorder at present. The severity of the person's stuttering would correspond to the amount of speech therapy needed to decrease disfluency. For severe stuttering, long-term therapy and hard work is required to decrease disfluency.
  • 4.2K
  • 23 Nov 2022
Topic Review
Medical Robots
The combination of artificial intelligence technology and medical science has inspired the emergence of medical robots with novel functions that use new materials and have a neoteric appearance. 
  • 4.2K
  • 02 Jun 2021
Topic Review
Goose Bumps
Goose bumps, goosebumps or goose-pimples are the bumps on a person's skin at the base of body hairs which may involuntarily develop when a person is tickled, cold or experiencing strong emotions such as fear, euphoria or sexual arousal. The formation of goose bumps in humans under stress is considered to be a vestigial reflex. Its function in other apes is to raise the body's hair, and would have made human ancestors appear larger to scare off predators or to increase the amount of air trapped in the fur to make it more insulating. The reflex of producing goose bumps is known as piloerection or the pilomotor reflex, or, more traditionally, horripilation. It occurs in many mammals; a prominent example is porcupines, which raise their quills when threatened, or sea otters when they encounter sharks or other predators.
  • 4.2K
  • 29 Nov 2022
Topic Review
Vegetables Irrigated with Untreated Wastewater
Vegetables are commonly cultivated with untreated wastewater and consumed by human beings who often ignore their harmful impacts on health. The industrialization and urbanization in developing countries have led to the release of increasing amounts of heavy metals (HM) into the environment. Regular monitoring of metal concentration levels in contaminated soils and edible plants is essential to prevent their excessive build-up in the diet and food chains.
  • 4.2K
  • 25 Dec 2020
Topic Review Peer Reviewed
Joanna I of Anjou (1343–1382)
Joanna I of Anjou (1325–1382), countess of Provence and the fourth sovereign of the Angevin dynasty in south Italy (since 1343), became the heir to the throne of the Kingdom of Sicily, succeeding her grandfather King Robert “the Wise” (1277–1343). The public and official images of the queen and the “symbolic” representations of her power, commissioned by her or by her entourage, contributed to create a new standard in the cultural references of the Angevin iconographic tradition aiming to assimilate models shared by the European ruling class. In particular, the following works of art and architecture will be analyzed: the queen’s portraits carved on the front slabs of royal sepulchers (namely those of her mother Mary of Valois and of Robert of Anjou) and on the liturgical furnishings in the church of Santa Chiara in Naples; the images painted in numerous illuminated manuscripts, in the chapter house of the friars in the Franciscan convent of Santa Chiara in Naples, in the lunette of the church in the Charterhouse of Capri. The church of the Incoronata in Naples does not show, at the present time, any portrait of the queen or explicit reference to Joanna as a patron. However, it is considered the highest symbolic image of her queenship. 
  • 4.2K
  • 13 Apr 2022
Topic Review
The Autonomic Nervous System Interaction with Immunity
The autonomic nervous system (ANS) and the immune system are deeply interrelated. The ANS regulates both innate and adaptive immunity through the sympathetic and parasympathetic branches, and an imbalance in this system can determine an altered inflammatory response as typically observed in chronic conditions such as systemic autoimmune diseases. Rheumatoid arthritis, systemic lupus erythematosus, and systemic sclerosis all show a dysfunction of the ANS that is mutually related to the increase in inflammation and cardiovascular risk. Moreover, an interaction between ANS and the gut microbiota has direct effects on inflammation homeostasis. Recently vagal stimulation techniques have emerged as an unprecedented possibility to reduce ANS dysfunction, especially in chronic diseases characterized by pain and a decreased quality of life as well as in chronic inflammation.
  • 4.2K
  • 07 Mar 2022
Topic Review
Recession of 1937–38
The recession of 1937–1938 was an economic downturn that occurred during the Great Depression in the United States. By the spring of 1937, production, profits, and wages had regained their early 1929 levels. Unemployment remained high, but it was slightly lower than the 25% rate seen in 1933. The American economy took a sharp downturn in mid-1937, lasting for 13 months through most of 1938. Industrial production declined almost 30 percent, and production of durable goods fell even faster. Unemployment jumped from 14.3% in May 1937 to 19.0% in June 1938. Manufacturing output fell by 37% from the 1937 peak and was back to 1934 levels. Producers reduced their expenditures on durable goods, and inventories declined, but personal income was only 15% lower than it had been at the peak in 1937. In most sectors, hourly earnings continued to rise throughout the recession, partly compensating for the reduction in the number of hours worked. As unemployment rose, consumer expenditures declined, leading to further cutbacks in production.
  • 4.2K
  • 25 Oct 2022
Biography
Ziauddin Sardar
Ziauddin Sardar (Urdu: ضیاء الدین سردار‎; born 31 October 1951) is a British-Pakistani scholar, award-winning writer, cultural critic and public intellectual who specialises in Muslim thought, the future of Islam, futurology and science and cultural relations. The author of more than 50 books,[1] Prospect magazine has named him as one of Britain's top 100 public intellectuals and
  • 4.2K
  • 11 Nov 2022
Topic Review
Biofuels for Internal Combustion Engine
Biofuel, a cost-effective, safe, and environmentally benign fuel produced from renewable sources, has been accepted as a sustainable replacement and a panacea for the damaging effects of the exploration for and consumption of fossil-based fuels.
  • 4.2K
  • 28 Sep 2021
Topic Review
Radio Direction Finder
A radio direction finder (RDF) is a device for finding the direction, or bearing, to a radio source. The act of measuring the direction is known as radio direction finding or sometimes simply direction finding (DF). Using two or more measurements from different locations, the location of an unknown transmitter can be determined; alternately, using two or more measurements of known transmitters, the location of a vehicle can be determined. RDF is widely used as a radio navigation system, especially with boats and aircraft. RDF systems can be used with any radio source, although the size of the receiver antennas are a function of the wavelength of the signal; very long wavelengths (low frequencies) require very large antennas, and are generally used only on ground-based systems. These wavelengths are nevertheless very useful for marine navigation as they can travel very long distances and "over the horizon", which is valuable for ships when the line-of-sight may be only a few tens of kilometres. For aircraft, where the horizon at altitude may extend to hundreds of kilometres, higher frequencies can be used, allowing much smaller antennas. An automatic direction finder, often capable of being tuned to commercial AM radio transmitters, is a feature of almost all modern aircraft. For the military, RDF systems are a key component of signals intelligence systems and methodologies. The ability to locate the position of an enemy transmitter has been invaluable since World War I, and it played a key role in World War II's Battle of the Atlantic. It is estimated that the UK's advanced "huff-duff" systems were directly or indirectly responsible for 24% of all U-boats sunk during the war. Modern systems often use phased array antennas to allow rapid beam forming for highly accurate results. These are generally integrated into a wider electronic warfare suite. Several distinct generations of RDF systems have been used over time, following new developments in electronics. Early systems used mechanically rotated antennas that compared signal strengths from different directions, and several electronic versions of the same concept followed. Modern systems use the comparison of phase or doppler techniques which are generally simpler to automate. Modern pseudo-Doppler direction finder systems consist of a number of small antennas fixed to a circular card, with all of the processing performed by software. Early British radar sets were also referred to as RDF, which was a deception tactic. However, the terminology was not inaccurate; the Chain Home systems used separate omnidirectional broadcasters and large RDF receivers to determine the location of the targets.
  • 4.2K
  • 10 Oct 2022
Topic Review Peer Reviewed
Machine Learning for Additive Manufacturing
Additive manufacturing (AM) is the name given to a family of manufacturing processes where materials are joined to make parts from 3D modelling data, generally in a layer-upon-layer manner. AM is rapidly increasing in industrial adoption for the manufacture of end-use parts, which is therefore pushing for the maturation of design, process, and production techniques. Machine learning (ML) is a branch of artificial intelligence concerned with training programs to self-improve and has applications in a wide range of areas, such as computer vision, prediction, and information retrieval. Many of the problems facing AM can be categorised into one or more of these application areas. Studies have shown ML techniques to be effective in improving AM design, process, and production but there are limited industrial case studies to support further development of these techniques.
  • 4.2K
  • 13 Apr 2022
Topic Review
Anthocyanidins and Anthocyanins
Anthocyanidins are colored molecules having medium-size and belonging to the class of flavonoids.
  • 4.2K
  • 24 May 2021
Topic Review
History of Intersex Surgery
The history of intersex surgery is intertwined with the development of the specialities of pediatric surgery, pediatric urology, and pediatric endocrinology, with our increasingly refined understanding of sexual differentiation, with the development of political advocacy groups united by a human qualified analysis, and in the last decade by doubts as to efficacy, and controversy over when and even whether some procedures should be performed. Prior to the medicalization of intersex, Canon and common law referred to a person's sex as male, female or hermaphrodite, with legal rights as male or female depending on the characteristics that appeared most dominant. The foundation of common law, the Institutes of the Lawes of England described how a hermaphrodite could inherit "either as male or female, according to that kind of sexe which doth prevaile." Single cases have been described by legal cases sporadically over the centuries. Modern ideas of medicalization of intersex and birth defects can be traced to French anatomist Isidore Geoffroy Saint-Hilaire (1805–1861), who pioneered the field of teratology. Since the 1920s surgeons have attempted to "fix" an increasing variety of conditions. Success has often been partial and surgery is often associated with minor or major, transient or permanent complications. Techniques in all fields of surgery are frequently revised in a quest for higher success rates and lower complication rates. Some surgeons, well aware of the immediate limitations and risks of surgery, feel that significant rates of imperfect outcomes are no scandal (especially for the more severe and disabling conditions). Instead they see these negative outcomes as a challenge to be overcome by improving the techniques. Genital reconstruction evolved within this tradition. In recent decades, nearly every aspect of this perspective has been called into question, with increasing concern regarding the human rights implications of medical interventions.
  • 4.2K
  • 01 Nov 2022
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