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Topic Review
J/Psi Meson
The J/ψ (J/psi) meson /ˈdʒeɪ ˈsaɪ ˈmiːzɒn/ or psion is a subatomic particle, a flavor-neutral meson consisting of a charm quark and a charm antiquark. Mesons formed by a bound state of a charm quark and a charm anti-quark are generally known as "charmonium". The J/ψ is the most common form of charmonium, due to its spin of 1 and its low rest mass. The J/ψ has a rest mass of 3.0969 GeV/c2, just above that of the ηc (2.9836 GeV/c2), and a mean lifetime of 7.2×10−21 s. This lifetime was about a thousand times longer than expected. Its discovery was made independently by two research groups, one at the Stanford Linear Accelerator Center, headed by Burton Richter, and one at the Brookhaven National Laboratory, headed by Samuel Ting of MIT. They discovered they had actually found the same particle, and both announced their discoveries on 11 November 1974. The importance of this discovery is highlighted by the fact that the subsequent, rapid changes in high-energy physics at the time have become collectively known as the "November Revolution". Richter and Ting were awarded the 1976 Nobel Prize in Physics.
  • 3.0K
  • 09 Nov 2022
Topic Review
Mad Pride
Mad Pride is a mass movement of the users of mental health services, former users, and the aligned, and that individuals with mental illness should be proud of their 'mad' identity. It was formed in 1993 in response to local community prejudices towards people with a psychiatric history living in boarding homes in the Parkdale area of Toronto, Ontario, Canada, and an event has been held every year since then in the city except for 1996. A similar movement began around the same time in the United Kingdom. By the late 1990s similar events were being organized under the Mad Pride name around the globe, including Australia, Ireland, Portugal, Brazil, Madagascar, South Africa and the United States. Events draw thousands of participants, according to MindFreedom International, a United States mental health advocacy organization that promotes and tracks events spawned by the movement. Mad Pride activists seek to reclaim terms such as "mad", "nutter", and "psycho" from misuse, such as in tabloid newspapers and in order to switch it from a negative message into a positive one. Through a series of mass media campaigns, Mad Pride activists seek to re-educate the general public on such subjects as the causes of mental disabilities, the experiences of those using the mental health system, and the global suicide pandemic. One of Mad Pride's founding activists in the UK was Pete Shaughnessy, who later died by suicide. Mark Roberts, Robert Dellar (who died in 2016) and Simon Barnet were among the other founders of the movement. Mad Pride: A celebration of mad culture records the early Mad Pride movement. On Our Own: Patient-Controlled Alternatives to the Mental Health System, published in 1978 by Judi Chamberlin, is a foundational text in the Mad Pride movement, although it was published before the movement was launched. The first known event, specifically organized as a Pride event by people who identified as survivors, consumers or ex-patients of psychiatric practices, was held on 18 September 1993, when it was called "Psychiatric Survivor Pride Day".
  • 3.0K
  • 17 Nov 2022
Topic Review
Halitosis
Halitosis, also known as fetor ex ore, bad breath or oral malodor, is a common disorder meaning unpleasant smell from the mouth. Halitosis is a common problem that manifests as an unpleasant and disgusting odor emanating from the mouth[1]. Malodor is mainly caused by putrefactive actions of microorganisms on endogenous or exogenous proteins and peptides. Oral malodor is an embarrassing condition that affects a large percentage of the human population. This condition often results in nervousness, humiliation, and social difficulties, such as the inability to approach people and speak to them[2][3][4][5][6].
  • 3.0K
  • 11 Sep 2020
Topic Review
Climate Oscillation
A climate oscillation or climate cycle is any recurring cyclical oscillation within global or regional climate, and is a type of climate pattern. These fluctuations in atmospheric temperature, sea surface temperature, precipitation or other parameters can be quasi-periodic, often occurring on inter-annual, multi-annual, decadal, multidecadal, century-wide, millennial or longer timescales. They are not perfectly periodic and a Fourier analysis of the data does not give a sharp spectrum. A prominent example is the El Niño Southern Oscillation, involving sea surface temperatures along a stretch of the equatorial Central and East Pacific Ocean and the western coast of tropical South America, but which affects climate worldwide. Records of past climate conditions are recovered through geological examination of proxies, found in glacier ice, sea bed sediment, tree ring studies or otherwise.
  • 3.0K
  • 09 Nov 2022
Topic Review
Premature Ovarian Insufficiency and Infertility
Reproductive aging is on the rise globally and inseparable from the entire aging process. An extreme form of reproductive aging is premature ovarian insufficiency (POI), which to date has mostly been of idiopathic etiology, thus hampering further clinical applications and associated with enormous socioeconomic and personal costs. In the field of reproduction, timely diagnosis with a clear understanding of the various comorbidities that can arise from estrogen deficiency and the important functional role of inflammation-induced ovarian deterioration are research hotspots for appropriate counseling and preventing this prematurely ovarian aging disease. It is evident that more research is required to allow pre-emptive identification of the at-risk population and to identify mechanisms that, if addressed promptly, can prolong ovarian function and fertility.
  • 3.0K
  • 30 Dec 2022
Topic Review
Integrated Photovoltaic-Fuel Cell Systems
Integrated photovoltaic-fuel cell (IPVFC) system uses photovoltaics and fuel cells to majorly generate power and hydrogen, using solar energy as the prime mover. IPVFC amongst other integrated energy generation methodologies are renewable and clean energy technologies that have received diverse research and development attentions over the last few decades due to their potential applications in a hydrogen economy.
  • 3.0K
  • 29 Oct 2021
Topic Review
ZnO and TiO2 Green Synthesis
Over the last two decades, oxide nanostructures have been continuously evaluated and used in many technological applications. The advancement of the controlled synthesis approach to design desired morphology is a fundamental key to the discipline of material science and nanotechnology. These nanostructures can be prepared via different physical and chemical methods; however, a green synthesis approach is a promising way to produce these nanostructures with desired properties with time and energy savings and/or less use of hazardous chemicals. In this regard, ZnO and TiO2 nanostructures are prominent candidates for various applications given their thermal stability, non-toxicity and cost-effective. 
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  • 06 May 2021
Topic Review
Beneficial Biological Effects of Helichrysum italicum
Helichrysum italicum (family Asteraceae), due to its various beneficial biological effects, represents an important plant in the traditional medicine of Mediterranean countries. There is a renewed interest in this medicinal plant, especially in investigations involving the isolation and identification of its bioactive compounds from extracts and essential oils, as well as in experimental validation of their pharmacological activities. The research is focused on the beneficial biological effects of Helichrysum italicum extracts, essential oils, and their major bioactive polyphenolic compounds, ranging from antioxidative, anti-inflammatory, and anticarcinogenic activities to their antiviral, antimicrobial, insecticidal, and antiparasitic effects.
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  • 08 Mar 2023
Topic Review
Ocotillol-Type Triterpenoids
Ginseng is one of the most widely consumed herbs in the world and plays an important role in counteracting fatigue and alleviating stress. The main active substances of ginseng are its ginsenosides. Ocotillol-type triterpenoid is a remarkably effective ginsenoside from Vietnamese ginseng that has received attention because of its potential antibacterial, anticancer and anti-inflammatory properties, among others. The semisynthesis, modification and biological activities of ocotillol-type compounds have been extensively studied in recent years.
  • 3.0K
  • 09 Dec 2020
Topic Review
Amino Acid Transporters
The conventional function of amino acid transporters in mammalian cells is in the maintenance of amino acid homeostasis. Every cell has a need for amino acids from extracellular sources, particularly for the essential amino acids that mammalian cells are not able to synthesize. This need cannot be met without the participation of specific transporters in the plasma membrane because of the hydrophilic nature of these amino acids, a feature that prevents their simple diffusion across the hydrophobic lipid bilayer. 
  • 3.0K
  • 02 Mar 2022
Topic Review
Mars (Planet)
Mars is the fourth planet from the Sun in our solar system and is named after Mars, the Roman god of war. Mars is also known as the "Red Planet" due to its reddish appearance when seen from Earth. The prefix areo-, from the Greek god of war, Ares, refers to Mars in the same way geo- refers to Earth. Until the first flyby of Mars by Mariner 4 in 1965, it was thought that Mars had channels of liquid water. Observations later showed that these channels do not exist. Still, of all the planets in our solar system other than Earth, Mars is the most likely to harbor liquid water, and perhaps life. Its rotational period and seasonal cycles are also similar to those of the Earth. It has the highest mountain in the solar system, Olympus Mons, the largest canyon in the solar system, Valles Marineris, and polar ice caps. Mars has two moons, Phobos and Deimos, which are small and oddly-shaped. These may be captured asteroids similar to 5261 Eureka, a Mars trojan asteroid. Mars can be seen from Earth by the naked eye. Its apparent magnitude reaches -2.9, a brightness surpassed only by Venus, the Moon, and the Sun. For much of the year, Jupiter may appear brighter to the naked eye than Mars. Mars is currently host to four orbiting spacecraft, more than any planet other than Earth. It is also home to the two Mars Exploration Rovers, Spirit and Opportunity.
  • 3.0K
  • 21 Nov 2022
Topic Review
Redoutable-Class Submarine (1931)
The Redoutable-class submarines were a group of 31 submarines built between 1924 and 1937 for the French Navy. Most of the class saw service during the Second World War. The class is also known in French as the Classe 1 500 tonnes, and they were designated as "First Class submarines", or "large submarine cruisers". They are known as the Redoutable class in reference to the lead boat Redoutable, in service from 1931 to 1942. The class is divided into two sub-class series, Type I, known as Le Redoutable and Type II, Pascal. Modern submarines when they were designed, they quickly became outdated, and were approaching obsolescence by the beginning of the Second World War. The conditions of the Armistice of 22 June 1940 prevented the Vichy government from carrying out a modernization programme. 24 out of the 29 units that served in the war were lost. Used in the defence of the Second French colonial empire under the Vichy regime, submarines of the class saw action against Allied offensives at the Battles of Dakar, Libreville and Madagascar. Many of the submarines of the class came under Allied control after the Allied landings in North Africa. Few however saw much further active service after this due to a period of refitting and alterations done in the United States between February 1943 and March 1945. One exception was Casabianca, which took part in the liberation of Corsica. The surviving submarines were largely used for training purposes after the war, with the last of them being disarmed in 1952.
  • 3.0K
  • 29 Nov 2022
Topic Review
Removal of Confederate Monuments and Memorials
For decades in the U.S., there have been isolated incidents of removal of Confederate monuments and memorials, although generally opposed in public opinion polls, and several U.S. States have passed laws over 115 years to hinder or prohibit further removals. In the wake of the Charleston church shooting in June 2015, several municipalities in the United States removed monuments and memorials on public property dedicated to the Confederate States of America. The momentum accelerated in August 2017 after the Unite the Right rally in Charlottesville, Virginia. The removals were driven by the belief that the monuments glorify white supremacy and memorialize a government whose founding principle was the perpetuation and expansion of slavery. Many of those who object to the removals, like President Trump, claim that the artifacts are part of the cultural heritage of the United States. Detractors claim that the vast majority of these Confederate monuments were built during the era of Jim Crow (1877–1954) and the Civil Rights Movement (1954–1968) not as memorials but as a means of intimidating African Americans and reaffirming white supremacy. The monuments have thus become highly politicized; according to Eleanor Harvey, a senior curator at the Smithsonian American Art Museum and a scholar of Civil War history: "If white nationalists and neo-Nazis are now claiming this as part of their heritage, they have essentially co-opted those images and those statues beyond any capacity to neutralize them again". Civil War historian James I. Robertson Jr. referred to the current climate to dismantle or destroy Confederate monuments as an "age of idiocy" and motivated by "elements hell-bent on tearing apart unity that generations of Americans have painfully constructed" and the monuments were not a "Jim Crow signal of defiance." In some Southern states, state law restricts or prohibits altogether the removal or alteration of public Confederate monuments. According to Stan Deaton, senior historian at the Georgia Historical Society, "These laws are the Old South imposing its moral and its political views on us forever more. This is what led to the Civil War, and it still divides us as a country. We have competing visions not only about the future but about the past." As Southern novelist William Faulkner famously put it, in the American South "the past is never dead. It's not even past."
  • 3.0K
  • 30 Nov 2022
Topic Review
Hypopigmented mycosis fungoides
Hypopigmented mycosis fungoides (HMF) is a variant of cutaneous T-cell lymphoma (CTCL), a heterogeneous group of extranodal non-Hodgkin’s lymphomas. HMF and classic (erythematous patch/plaque) Mycosis Fungoides (MF) display contrasting clinical characteristics: (i) HMF presents with light colored to achromic patches, as opposed to classic MF, which presents with erythematous scaly patches, plaques, tumors or erythroderma, (ii) HMF primarily affects individuals with darker skin types (Fitzpatrick phototypes IV-VI), while classic MF affects mostly Caucasians, (iii) HMF is commonly seen in pediatric/adolescents and young adults, whereas classic MF is more prevalent in elderly individuals, and (iv) the predominant malignant cells in HMF are CD8+T-cells, as opposed to CD4+T-cells in classic MF. Our recent review paper highlights that active antitumor immune response, specifically a Th1/cytotoxic antitumor immune response seen robustly in HMF, is likely responsible for the differential behavior between these two MF variants. Furthermore, we propose that the hypopigmentation (clinical sign) may serve as a surrogate marker for the presence of antitumor immune response and may portend better prognosis. 
  • 3.0K
  • 21 Oct 2020
Topic Review
Nanomaterials Combined with Bacteriocins
Bacteriocins are antimicrobial peptides or proteinaceous materials produced by bacteria against pathogens. These molecules have high efficiency and specificity and are equipped with many properties useful in food-related applications, such as food preservatives and additives, as well as biomedical applications, such as serving as alternatives to current antibacterial, antiviral, anti-cancer, and antibiofilm agents. Despite their advantages as alternative therapeutics over existing strategies, several limitations of bacteriocins, such as the high cost of isolation and purification, narrow spectrum of activity, low stability and solubility, and easy enzymatic degradation, need to be improved. Nanomaterials are promising agents in many biological applications. They are widely used in the conjugation or decoration of bacteriocins to augment the activity of bacterioc-ins or reduce problems related to their use in biomedical applications. Therefore, bacteriocins combined with nanomaterials have emerged as promising molecules that can be used in various biomedical applications.
  • 3.0K
  • 11 Oct 2021
Topic Review
Carboxylases for CO2 Biotransformation
The rapid growth of atmospheric CO2 concentration by continuous consumption of fossil fuels is one of the main causes of global warming. Turning CO2 into fuels and chemicals through biotransformation offers a win-win strategy to both decrease atmospheric CO2 and efficiently exploit carbon resources. The overall efficiency of CO2 biotransformation in vitro and CO2 assimilation in vivo is generally determined by the biochemical properties of carboxylases. Herein, we summarized carboxylases based on catalytic mechanism and CO2 biotransformation in vitro and CO2 assimilation in vivo based on newly mined or designed carboxylases. 
  • 3.0K
  • 04 Mar 2021
Topic Review
Tracked Locomotion Systems for Ground Mobile Robots
Service robotics is presently one of the fastest-growing technological fields. Nevertheless, while Automated Guided Vehicles (AGV) moving on flat and compact grounds are already commercially available and widely used to move components and products inside industrial buildings, the extensive application of ground mobile robots in environments that are unstructured or structured for humans is a promising challenge for the next years. The important application fields are agriculture, planetary exploration, reconnaissance in dangerous situations, such as radioactive or chemical contamination, homeland security and military operations, demining, intervention in case of terrorist attacks, and surveillance.
  • 3.0K
  • 26 Aug 2022
Topic Review
Safe Mode (Spacecraft)
Safe mode is an operating mode of a modern unmanned spacecraft during which all non-essential systems are shut down and only essential functions such as thermal management, radio reception and attitude control are active. Safe mode is entered automatically upon the detection of a predefined operating condition or event that may indicate loss of control or damage to the spacecraft. Usually the trigger event is a system failure or detection of operating conditions considered dangerously out of the normal range. Cosmic rays penetrating spacecraft electrical systems can create false signals or commands and thus cause a trigger event. The central processor electronics are especially prone to such events. Another trigger is the lack of a received command within a given time window. Lack of received commands can be caused by hardware failures or mis-programming of the spacecraft, as in the case of the Viking 1 lander. The process of entering safe mode, sometimes referred to as safing, involves a number of immediate physical actions taken to prevent damage or complete loss. Power is removed from non-essential subsystems. Regaining attitude control, if lost, is the highest priority because it is necessary to maintain thermal balance and proper illumination of the solar panels. A tumbling or cartwheeling spacecraft can quickly roast, freeze or exhaust its battery power and be lost forever.
  • 3.0K
  • 02 Nov 2022
Biography
Julius Edgar Lilienfeld
Julius Edgar Lilienfeld (April 18, 1882 – August 28, 1963) was a Jewish Austro-Hungarian-born German-American physicist and electronic engineer, credited with the first patents on the field-effect transistor (FET) (1925) and electrolytic capacitor (1931). Because of his failure to publish articles in learned journals and because high-purity semiconductor materials were not available yet, his
  • 3.0K
  • 10 Nov 2022
Topic Review
Proposed Melbourne Rail Extensions
Several proposals have been put forward by various groups to expand the Melbourne rail network—proposals for additional rail lines, extensions to existing lines, as well as electrification to existing lines and new stations on existing lines. Some of these plans were so seriously considered at various times that they appeared in the Melway street directory, and on suburban train destination rolls.
  • 3.0K
  • 31 Oct 2022
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