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Topic Review
Melanin
Melanin (/ˈmɛlənɪn/ (listen); from Greek: μέλας, romanized: melas, lit. 'black, dark') is a broad term for a group of natural pigments found in most organisms. Eumelanin is produced through a multistage chemical process known as melanogenesis, where the oxidation of the amino acid tyrosine is followed by polymerization. The melanin pigments are produced in a specialized group of cells known as melanocytes. Functionally, eumelanin serves as protection against UV radiation. Melanin (neuromelanin) functions as the catalyst of all cellular functions within an organism. There are five basic types of melanin: eumelanin, pheomelanin, neuromelanin, allomelanin and pyomelanin. The most common type is eumelanin, of which there are two types— brown eumelanin and black eumelanin. Pheomelanin, which is produced when melanocytes are malfunctioning due to derivation of the gene to its recessive format is a cysteine-derivative that contains polybenzothiazine portions that are largely responsible for the of red yellow tint given to some skin or hair colors. Neuromelanin is found in the brain. Research has been undertaken to investigate its efficacy in treating neurodegenerative disorders such as Parkinson's. Allomelanin and pyomelanin are two types of nitrogen-free melanin. In the human skin, melanogenesis is initiated by exposure to UV radiation, causing the skin to darken. Eumelanin is an effective absorbent of light; the pigment is able to dissipate over 99.9% of absorbed UV radiation. Because of this property, eumelanin is thought to protect skin cells from UVA and UVB radiation damage, reducing the risk of folate depletion and dermal degradation. It is considered that exposure to UV radiation is associated with increased risk of malignant melanoma, a cancer of melanocytes (melanin cells). Studies have shown a lower incidence for skin cancer in individuals with more concentrated melanin, i.e. darker skin tone.
  • 2.7K
  • 28 Sep 2022
Topic Review
Egyptian Honeybee
The Egyptian honeybee (Apis mellifera lamarckii) is one of the honeybee subspecies known for centuries since the ancient Egypt civilization. The subspecies of the Egyptian honeybee is distinguished by certain traits of appearance and behavior that were well-adapted to the environment and unique in a way that it is resistant to bee diseases, such as the Varroa disease. The subspecies is different than those found in Europe and is native to southern Egypt.
  • 2.7K
  • 21 Oct 2022
Topic Review
The Concept of Sustainability and the Sustainable Pillars
The concept of sustainability or sustainable development is based on the German word “Nachhaltigkeit”, which was defined in the book Sylvicultura Oeconomica, by von Carlowitz. Implementing sustainability can be traced back to the year 1713, when it was used in relation to the forest industry, along with an implemented discussion of whether a forest can recover from humans’ wood consumption.
  • 2.7K
  • 29 May 2023
Topic Review
Hamzanama
The Hamzanama (Persian/Urdu: حمزه نامه Hamzenâme, Epic of Hamza) or Dastan-e-Amir Hamza (Persian/Urdu: داستان امیر حمزه Dâstâne Amir Hamze, "Adventures of Amir Hamza") narrates the legendary exploits of Amir Hamza, or Hamza ibn Abdul-Muttalib, an uncle of Muhammad. Most of the stories are extremely fanciful, "a continuous series of romantic interludes, threatening events, narrow escapes, and violent acts". The Hamzanama chronicles the fantastic adventures of Hamza as he and his band of heroes fight against the enemies of Islam. The stories, from a long-established oral tradition, were written down in Persian, the language of the courts of Persianate societies, in multiple volumes presumably in the era of Mahmud of Ghazni. In the West, the work is best known for the enormous illustrated manuscript commissioned by the Mughal emperor Akbar about 1562. The text augmented the story, as traditionally told in dastan performances. The dastan (storytelling tradition) about Amir Hamza persists far and wide up to Bengal and Arakan, as the Mughal Empire controlled those territories. The longest version of the Hamzanama exists in Urdu and contains 46 volumes in approximately over 45,000 pages.
  • 2.7K
  • 24 Oct 2022
Topic Review
Flavonoid-Auxin/Cytokinin Link and Symbiosis
Flavonoid biosynthesis is responsive to a wide range of stresses, and the numerous synthesized flavonoid species offer two main evolutionary advantages to land plants. First, flavonoids are antioxidants and thus defend plants against those adverse conditions that lead to the overproduction of reactive oxygen species. Second, flavonoids aid in protecting plants against water and nutrient deficiency by modulating root development and establishing symbiotic relations with beneficial soil fungi and bacteria. 
  • 2.7K
  • 10 Feb 2023
Topic Review
Solid Lipid Nanoparticles vs. Nanostructured Lipid Carriers
Solid–lipid nanoparticles and nanostructured lipid carriers are delivery systems for the delivery of drugs and other bioactives used in diagnosis, therapy, and treatment procedures. These nanocarriers may enhance the solubility and permeability of drugs, increase their bioavailability, and extend the residence time in the body, combining low toxicity with a targeted delivery. Nanostructured lipid carriers are the second generation of lipid nanoparticles differing from solid lipid nanoparticles in their composition matrix. The use of a liquid lipid together with a solid lipid in nanostructured lipid carrier allows it to load a higher amount of drug, enhance drug release properties, and increase its stability. Therefore, a direct comparison between solid lipid nanoparticles and nanostructured lipid carriers is needed. 
  • 2.7K
  • 30 May 2023
Topic Review
Requirements Engineering in OTF-Computing
The idea of On-The-Fly (OTF) Computing is to compose and provide software services ad hoc, based on requirement descriptions in natural language. Since non-technical users write  their software requirements themselves and in unrestricted natural language, deficits occur such as inaccuracy and incompleteness. These deficits are usually tackled by natural language processing methods, which have to face specific challenges in OTF Computing because maximum automation is the goal there. In the following, we present current automatic approaches for solving inaccuracies and incompleteness in natural language requirement descriptions.
  • 2.7K
  • 30 Oct 2020
Topic Review
Electric Vehicles
E-mobility sustainability assessment is becoming more comprehensive with research integrating social aspects without focusing only on technical, economic, and/or environmental perspectives. The transportation sector is indeed one of the leading and most challenging greenhouse-gas polluters, and e-mobility is seen as one of the potential solutions; however, a social perspective must be further investigated to improve the perception of and acceptance of electric vehicles. 
  • 2.7K
  • 04 Feb 2021
Topic Review
Applications of Magnesium and Alloys
Since its discovery, magnesium has played an influential role in society. In its early days, military applications and wars fueled its growth. For example, magnesium was weaponized to construct incendiary bombs, flares, and ammunitions that were subsequently deployed in World War II, and it caused massive conflagrations and widespread devastations. Post-War, magnesium’s availability and unique blend of properties were explored and were found to be highly attractive for an extensive range of applications. Today, magnesium is used for engineering applications in automotive, aerospace, and consumer electronics. In addition, it has a role in organic chemistry and pharmaceuticals and is used to construct several general-purpose applications, such as sporting goods, household products, and office equipment.
  • 2.7K
  • 09 Oct 2021
Topic Review
Ocean Wave Power Generation Systems
According to the theory of mechanical vibration, only when the wave power generation system resonates with the ocean wave can the energy of the ocean wave be converted into electric energy to the greatest extent. Several topics are discussed: the current situation of ocean wave power generation system tests in real ocean waves; the optimization design of linear generator for converting ocean wave energy into electrical energy; some optimization control methods to improve the operational efficiency of ocean wave power generation systems; and the current policy and financial support of ocean wave power generation in some countries. 
  • 2.7K
  • 04 Jan 2022
Topic Review
Queen Snake
The queen snake (Regina septemvittata) is a species of nonvenomous semiaquatic snake, a member of the subfamily Natricinae of the family Colubridae. The species is endemic to North America.
  • 2.7K
  • 24 Oct 2022
Topic Review
First-Price Sealed-Bid Auction
A first-price sealed-bid auction (FPSBA) is a common type of auction. It is also known as blind auction. In this type of auction, all bidders simultaneously submit sealed bids, so that no bidder knows the bid of any other participant. The highest bidder pays the price they submitted.:p2
  • 2.7K
  • 01 Dec 2022
Topic Review
TERT Promoter Mutations in Gliomas
Telomere length maintenance systems perform an essential function in preserving genome stability. Abnormalities in the functioning of these systems, such as telomerase reactivation, usually play a key role in the course of oncogenesis.TERTp mutations are not found in ordinary human cells, but are often associated with malignant tumor progression and increased cell proliferation in CNS tumor diseases, especially in gliomas. The availability of molecular evaluation of the TERTp mutational status of CNS tumor lesions contributes to more accurate and reliable diagnosis and timely decisions regarding patient follow-up with selection of the most appropriate and applicable treatment protocols.
  • 2.7K
  • 12 Apr 2022
Topic Review
Betaine in Cereal Grains
Betaine is a non-essential nutrient which performs several important physiological functions in organisms. Abundant data exist to suggest that betaine has a potential for prevention of chronic diseases and that its dietary intake may contribute to overall health enhancement. 
  • 2.7K
  • 15 Jul 2021
Topic Review
Spare Parts with Additive Manufacturing of Aviation Industry
Additive manufacturing (AM) is a digital technology of layered fabrication by adding material where no cutting tool is required as in the case of a subtractive manufacturing process. AM is bridging the digital and physical world as a 3D computer-aided manufacturing (CAM) method. The usage of AM has made the supply chain of the aviation spare parts industry simpler, more effective, and efficient.
  • 2.7K
  • 12 May 2022
Topic Review
Ion-selective Electrodes
An Ion-selective electrode (ISE) is a transducer (sensor) which converts the activity of a specific ion dissolved in a solution into an electrical potential which can be measured by a voltmeter or pH meter. The voltage is theoretically dependent on the logarithm of the ionic activity, according to the Nernst equation. The sensing part of the electrode is usually made as an ion-specific membrane, along with a reference electrode. Ion-selective electrodes are used in biochemical and biophysical research, where measurements of ionic concentration in an aqueous solution are required, usually on a real time basis.
  • 2.7K
  • 10 Oct 2022
Topic Review
CAR-T Cells in Pancreatic cancer
Pancreatic cancer has the worst prognosis and lowest survival rate among all types of cancers and thus, there exists a strong need for novel therapeutic strategies. Chimeric antigen receptor (CAR)-modified T cells present a new potential option after successful FDA-approval in hematologic malignancies, however, current CAR T cell clinical trials in pancreatic cancer failed to improve survival and were unable to demonstrate any significant response. The physical and environmental barriers created by the distinct tumor microenvironment (TME) as a result of the desmoplastic reaction in pancreatic cancer present major hurdles for CAR T cells as a viable therapeutic option in this tumor entity. Cancer cells and cancer-associated fibroblasts express extracellular matrix molecules, enzymes, and growth factors, which can attenuate CAR T cell infiltration and efficacy. Recent efforts demonstrate a niche shift where targeting the TME along CAR T cell therapy is believed or hoped to provide a substantial clinical added value to improve overall survival.
  • 2.7K
  • 16 Oct 2020
Topic Review
Antimicrobial Resistance
The discovery of antibiotics has revolutionized the medicine and treatment of microbial infections. However, the current scenario has highlighted the difficulties in marketing new antibiotics and an exponential increase in the appearance of resistant strains. Here, the main antibiotic resistance mechanisms are briefly listed with some examples. 
  • 2.7K
  • 05 Nov 2020
Topic Review
Atypical Chronic Myeloid Leukemia
Atypical chronic myeloid leukemia, BCR-ABL1 negative (aCML) is a rare myelodysplastic syndrome (MDS)/myeloproliferative neoplasm (MPN) with a high rate of transformation to acute myeloid leukemia, and poor survival. Until now, the diagnosis has been based on morphological grounds only, possibly making the real frequency of the disease underestimated. Only recently, new insights in the molecular biology of MDS/MPN syndromes have deepened our knowledge of aCML, enabling us to have a better molecular profile of the disease. The knowledge gleaned from next generation sequencing has complemented morphologic and laboratory WHO criteria for myeloid neoplasms and can provide greater specificity in distinguishing aCML from alternative MDS/MPN or MPNs. The most commonly mutated genes (> 20%) in aCML are SETBP1, ASXL1, N/K-RAS, SRSF2, and TET2, and less frequently (< 10%) CBL, CSFR3, JAK2, EZH2, and ETNK1. Several of these mutations affect the JAK-STAT, MAPK, and ROCK signaling pathways, which are targetable by inhibitors that are already in clinical use and may lead to a personalized treatment of aCML patients unfit for allogeneic transplant, which is currently the only curative option for fit patients. 
  • 2.7K
  • 27 Oct 2020
Topic Review
Recycled Concrete Aggregates Applications in Asphalt Paving
The sustainability of road pavements is highly influenced by the proper selection of the materials used in the production and construction. The material circularity principle aims to completely or partially replace traditional aggregates and fillers with wastes or by-products. Adapting asphalt mixtures to incorporate waste materials reduces the consumption of naturally mined materials, minimizing the carbon footprint and pavement industry’s impact on the environment. Furthermore, the use of waste materials minimizes landfill volumes and limits the disposal of waste produced from various sources. Thus, this document discusses the use of recycled concrete aggregates (RCA) from construction and demolition waste (CDW) as alternative aggregates for application in asphalt paving.
  • 2.7K
  • 06 May 2022
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