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Topic Review
P-Coumaric Acid in Cosmetics
p-Coumaric acid is a natural metabolite contained in many edible plants, and its antioxidant activities in reducing oxidative stress and inflammatory reactions have been demonstrated in various experimental models. p-Coumaric acid has an optimal structure to be a competitive inhibitor of tyrosinase that catalyzes key reactions in the melanin biosynthetic pathway. Experimental evidence supports this notion as it was found to be a more potent inhibitor of tyrosinase, especially toward human enzymes, than other well-known tyrosinase inhibitors such as arbutin and kojic acid. p-Coumaric acid inhibited melanin synthesis in murine melanoma cells, human epidermal melanocytes, and 3-dimensionally reconstituted human skin models. Ex vivo skin permeation experiments and in vivo efficacy tests for p-coumaric acid confirmed its efficient transdermal delivery and functional efficacy in reducing erythema development and skin pigmentation due to ultraviolet exposure. Human studies further supported its effectiveness in hypopigmentation and depigmentation. These findings suggest that p-coumaric acid has good potential to be used as a skin-lightening active ingredient in cosmetics. 
  • 3.5K
  • 30 Jul 2021
Topic Review
Polycom
Polycom, now a part of Plantronics, was an American multinational corporation that develops video, voice and content collaboration and communication technology. Polycom was co-founded in 1990 by Brian L Hinman and Jeffrey Rodman. In 2018 Polycom was acquired by Plantronics and in 2019 the name of the combined entity was changed to Poly. On March 28, 2022 HP Inc. announced it would be acquiring Poly (company) in a deal totaling $1.7 billion USD.
  • 3.5K
  • 09 Nov 2022
Topic Review
Wireless Sensor Networks Architecture
Wireless sensor networks (WSNs) have taken a giant leap in scale, expanding their applicability to a large variety of technological domains and applications, ranging from the Internet of things (IoT) for smart cities and smart homes to wearable technology healthcare applications, underwater, agricultural and environmental monitoring and many more. This expansion is rapidly growing every passing day in terms of the variety, heterogeneity and the number of devices which such applications support. Data collection is commonly the core application in WSN and IoT networks, which are typically composed of a large variety of devices, some constrained by their resources (e.g., processing, storage, energy) and some by highly diverse demands. Many challenges span all the conceptual communication layers, from the Physical to the Applicational. In addition, the integrated unit architecture and the platform design can be subject to various stringent constraints. For example, size requirements can impose a strict constraint on the device design; low power consumption, low production cost, and self-operation can represent additional constraints.  Accordingly, the device architecture is fundamental and affects many other factors in the system. For example, power supply affects the life span; it also affects transmission range, memory, and processing unit, which in turn can affect the algorithms that can be executed on the device, etc.
  • 3.5K
  • 12 Apr 2022
Topic Review
Medical Thermometer
A medical thermometer (also called clinical thermometer) is used for measuring human or animal body temperature. The tip of the thermometer is inserted into the mouth under the tongue (oral or sub-lingual temperature), under the armpit (axillary temperature), into the rectum via the anus (rectal temperature), into the ear (tympanic temperature), or on the forehead (temporal temperature).
  • 3.5K
  • 04 Nov 2022
Topic Review
Almonds (Prunus dulcis)
Almond (Prunus dulcis) is a tree species that together with peach is included in the subgenus Amygdalus.
  • 3.5K
  • 02 Mar 2021
Topic Review
Bloodlands
Bloodlands: Europe Between Hitler and Stalin is a book by Yale historian Timothy D. Snyder that was first published by Basic Books on October 28, 2010. In the book, Snyder examines the political, cultural and ideological context tied to a specific region of Central and Eastern Europe, where Joseph Stalin 's Soviet Union and Adolf Hitler's Nazi Germany committed mass killings of an estimated 14 million noncombatants between 1933 and 1945, the majority outside the death camps of the Holocaust. Snyder's thesis is that the "bloodlands", a region that is now Poland , Belarus , Ukraine , the Baltic states (Estonia, Latvia, and Lithuania), northeastern Romania, and the westernmost fringes of Russia , is the area that the regimes of Stalin and Hitler, despite their conflicting goals, interacted to increase suffering and bloodshed many times worse than any seen in western history. Snyder notes similarities between the two totalitarian regimes and also the enabling interactions that reinforced the destruction and the suffering that were brought to bear on noncombatants. Making use of many new primary and secondary sources from Central and Eastern Europe, Snyder brings scholarship to many forgotten, misunderstood, or incorrectly-remembered parts of the history, and he particularly notes that most of the victims were killed outside the concentration camps of the respective regimes. The book earned many positive reviews and has been called "revisionist history of the best kind". It was awarded numerous prizes, including the 2013 Hannah Arendt Prize for Political Thought.
  • 3.5K
  • 28 Nov 2022
Topic Review
Sportsmanship
Sportsmanship is an aspiration or ethos that a sport or activity will be enjoyed for its own sake. This is with proper consideration for fairness, ethics, respect, and a sense of fellowship with one's competitors. A "sore loser" refers to one who does not take defeat well, whereas a "good sport" means being a "good winner" as well as being a "good loser" (someone who shows courtesy towards another in a sports game).
  • 3.5K
  • 16 Nov 2022
Topic Review Peer Reviewed
Gross Pathology in COVID-19
The global infectious disease COVID-19 is caused by SARS-CoV-2, a new member of the Coronaviridae family. Though presented as a novel disease that primarily affects the respiratory system, multi-organ involvement has been well-noticed and documented since the beginning of the pandemic. When performed properly with adequate safety measures, autopsy provides the most valuable information to decipher the pathogenesis of this novel disease, therefore providing a basis for clinical management. In addition to reviewing the macroscopic changes in organs and tissues involved in COVID-19, the relevant microscopic alterations and possible pathogenesis are also discussed.
  • 3.5K
  • 31 Oct 2022
Topic Review
Kikuchi Lines
Kikuchi lines are patterns of electrons formed by scattering. They pair up to form bands in electron diffraction from single crystal specimens, there to serve as "roads in orientation-space" for microscopists uncertain of what they are looking at. In transmission electron microscopes, they are easily seen in diffraction from regions of the specimen thick enough for multiple scattering. Unlike diffraction spots, which blink on and off as one tilts the crystal, Kikuchi bands mark orientation space with well-defined intersections (called zones or poles) as well as paths connecting one intersection to the next. Experimental and theoretical maps of Kikuchi band geometry, as well as their direct-space analogs e.g. bend contours, electron channeling patterns, and fringe visibility maps are increasingly useful tools in electron microscopy of crystalline and nanocrystalline materials. Because each Kikuchi line is associated with Bragg diffraction from one side of a single set of lattice planes, these lines can be labeled with the same Miller or reciprocal-lattice indices that are used to identify individual diffraction spots. Kikuchi band intersections, or zones, on the other hand are indexed with direct-lattice indices i.e. indices which represent integer multiples of the lattice basis vectors a, b and c. Kikuchi lines are formed in diffraction patterns by diffusely scattered electrons, e.g. as a result of thermal atom vibrations. The main features of their geometry can be deduced from a simple elastic mechanism proposed in 1928 by Seishi Kikuchi, although the dynamical theory of diffuse inelastic scattering is needed to understand them quantitatively. In x-ray scattering, these lines are referred to as Kossel lines (named after Walther Kossel).
  • 3.5K
  • 09 Nov 2022
Topic Review
Globalization and the COVID-19 Pandemic
The rapidly spreading COVID-19 pandemic in 2020 not only brought many countries in the world to a state of health crisis, but also increasingly drove economic and social crisis. The roots of these crises, however, run far deeper and can be traced to decades of neoliberal political and economic actions and driving forces of globalization. Increasing globalization and liberalization of markets led to the increasing privatization of many public goods while collectivizing risks such as environmental disasters, pandemics and economic crises. 
  • 3.5K
  • 23 Jul 2021
Topic Review
Andalusian Arabic
Andalusian Arabic, also known as Andalusi Arabic, was a variety or varieties of Arabic spoken in Al-Andalus, the regions of the Iberian Peninsula (modern Spain and Portugal) under Muslim rule (and for some time after) from the 9th century to the 17th century. It became an extinct language in Iberia after the expulsion of the former Hispanic Muslims, which took place over a century after the Granada War by the Catholic Monarchs of Spain. Once widely spoken in Iberia, the expulsions and persecutions of Arabic speakers caused an abrupt end to the language's use on the peninsula. Its use continued to some degree in North Africa after the expulsion, although Andalusi speakers were rapidly assimilated by the Maghrebi communities to which they fled.
  • 3.5K
  • 10 Oct 2022
Topic Review
Thallium
Thallium, as a pharmaceutical cosmetic product, is applied for facial hair removal and fungal infections of the scalp. Thallium acetate is currently used as a catalyst in organic synthesis in the oxidation of olefins and hydrocarbons, and in epoxidation and polymerization reactions. Detection of Tl is a challenging task because its concentration in environmental samples may be at a nanogram per gram level or lower.
  • 3.5K
  • 23 Nov 2021
Topic Review
Crow
A crow is a medium to large-sized bird of the genus Corvus within the family Corvidae, characterized by predominantly black plumage, a strong bill, and high intelligence. Crows are widely distributed across most continents, inhabiting forests, grasslands, agricultural lands, and urban environments. They are omnivorous, highly adaptable, and noted for complex social behaviors and advanced cognitive abilities.
  • 3.5K
  • 26 Sep 2025
Topic Review
Muscle
Muscle is a soft tissue found in most animals, and is one of the four basic animal tissues, along with nervous tissue, epithelium, and connective tissue. Muscle cells contain protein filaments called myofilaments of actin and myosin that slide past one another, producing a contraction that changes both the length and the shape of the cell. Muscles function to produce force and motion. They are primarily responsible for maintaining and changing posture, locomotion, as well as movement of internal organs, such as the contraction of the heart and the movement of food through the digestive system via peristalsis. Muscle tissue is derived from the embryonic mesodermal germ layer in a process known as myogenesis. There are three types of muscle, of which skeletal and cardiac muscle are striated and smooth muscle is not. Muscle action can be classified as being either voluntary or involuntary. Cardiac and smooth muscles contract without conscious thought and are termed involuntary, whereas the skeletal muscles contract upon command. Skeletal muscles in turn can be divided into fast and slow twitch fibers. Muscles are predominantly powered by the oxidation of fats and carbohydrates, but anaerobic chemical reactions are also used, particularly by fast twitch fibers. These chemical reactions produce adenosine triphosphate (ATP) molecules that are used to power the movement of the myosin heads. The term muscle is derived from the Latin musculus meaning "little mouse" perhaps because of the shape of certain skeletal muscles or because contracting muscles look like mice moving under the skin.
  • 3.5K
  • 22 Oct 2022
Topic Review
Stretching and Inflammation
Stretching is one of the popular elements in physiotherapy and rehabilitation. When correctly guided, it can help minimize or slow down the disabling effects of chronic health conditions. Most likely, the benefits are associated with reducing inflammation.
  • 3.5K
  • 13 Sep 2022
Topic Review
Melatonin as a Neurotrophic Factor
Melatonin, N-acetyl-5-hydroxytryptamine, is a hormone that synchronizes the internal environment with the photoperiod. It is synthesized in the pineal gland and greatly depends on the endogenous circadian clock located in the suprachiasmatic nucleus and the retina’s exposure to different light intensities. Among its most studied functions are the regulation of the waking-sleep rhythm and body temperature. Furthermore, melatonin has pleiotropic actions, which affect, for instance, the modulation of the immune and the cardiovascular systems, as well as the neuroprotection achieved by scavenging free radicals.
  • 3.5K
  • 19 Nov 2022
Topic Review
Moshi Monsters
Moshi Monsters is a British website aimed at children aged 6-12, with over 80 million registered users in 150 territories worldwide. Users choose from one of six virtual pet monsters (Diavlo, Luvli, Katsuma, Poppet, Furi and Zommer) they can create, name and nurture. Once their pet has been customized, players can navigate their way around Monstro City, take daily puzzle challenges to earn 'Rox' (a virtual currency), play games, personalize their room and communicate with other users in a safe environment (most of the time). Following its online success, Moshi Monsters has expanded commercially with physical products, including toys, Moshi Monsters Magazine (the number-one selling kids' magazine in the UK in 2011), a best-selling DS video game, a number 4 music album, books, membership cards, bath soap, chocolate calendars, trading cards, figures of many Moshlings, mobile games, and a Moshi Monsters feature film. In December 2012, eight Moshi Monster toys were included in McDonald's Happy Meals in the United States and Canada.
  • 3.5K
  • 30 Nov 2022
Topic Review
Lignin
Lignin is an extremely abundant substance that has a chemical functionality that endows it with the necessary properties to be an attractive platform material for the new millennium. We must continue to explore and exploit its potentiality as a stand-alone material, raw feedstock for refining to chemicals, polymeric filler, and co-composite material. This review highlights hardwood-derived lignin, a little explored form of lignin, as a promising platform material.
  • 3.5K
  • 13 Aug 2020
Topic Review
Life Cycle Assessment of Cellulose
The huge plastic production and plastic pollution are considered important global issues due to environmental aspects. One practical and efficient way to address them is to replace fossil-based plastics with natural-based materials, such as cellulose. The applications of different cellulose products have recently received increasing attention because of their desirable properties, such as biodegradability and sustainability.
  • 3.5K
  • 19 Feb 2021
Topic Review
Flavor
A food flavoring or food flavouring, [lower-alpha 1] in short flavoring or flavouring, or alternatively aroma is a food additive used to improve the taste or smell of food. It changes the perceptual impression of food as determined primarily by the chemical senses of the gustatory and olfactory system. The trigeminal nerves, which detect chemical irritants in the mouth and throat, as well as temperature and texture, are also important to the overall perception of food. Of the three chemical senses, smell is the main determinant of a food item's flavor. Aromas are the volatile components of the food. The aroma of a food is determined by the aroma compounds it contains and the personal ability to detect them. While an aroma primarily acts through te olfactory system, it also affects the taste at the same time. Along with additives, other components like sugars determine the taste of food. Five basic tastes – sweet, sour, bitter, salty and umami (savory) are universally recognized, although some cultures also include pungency and oleogustus ("fattiness"). The number of food smells is unbounded; a food's flavor, therefore, can be easily altered by changing its smell while keeping its taste similar. This is exemplified in artificially flavored jellies, soft drinks and candies, which, while made of bases with a similar taste, have dramatically different flavors due to the use of different scents or fragrances. The flavorings of commercially produced food products are typically created by flavorists. A flavoring is defined as a substance that gives another substance taste, altering the characteristics of the solute, causing it to become sweet, sour, tangy, etc. Although the term, in common language, denotes the combined chemical sensations of taste and smell, the same term is used in the fragrance and flavors industry to refer to edible chemicals and extracts that alter the flavor of food and food products through the sense of smell. Owing to the high cost, or unavailability of natural flavor extracts, most commercial flavorants are "nature-identical", which means that they are the chemical equivalent of natural flavors, but chemically synthesized rather than being extracted from source materials. Identification of components of natural foods, for example a raspberry, may be done using technology such as headspace techniques, so the flavorist can imitate the flavor by using a few of the same chemicals present. In the EU legislation, the term "natural-identical flavouring" does not exist. The legislation is specified on what is a "flavouring" and a "natural flavouring". A flavor is a quality of something that affects the sense of taste.
  • 3.5K
  • 04 Nov 2022
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