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Topic Review
Pentacene and Its Derivatives Deposition Methods
Pentacene is a well-known conjugated organic molecule with high mobility and a sensitive photo response. It is widely used in electronic devices, such as in organic thin-film transistors (OTFTs), organic light-emitting diodes (OLEDs), photodetectors, and smart sensors. With the development of flexible and wearable electronics, the deposition of good-quality pentacene films in large-scale organic electronics at the industrial level has drawn more research attention. Several methods are used to deposit pentacene thin films. The thermal evaporation technique is the most frequently used method for depositing thin films, as it has low contamination rates and a well-controlled deposition rate. Solution-processable methods such as spin coating, dip coating, and inkjet printing have also been widely studied because they enable large-scale deposition and low-cost fabrication of devices. 
  • 3.3K
  • 18 Apr 2022
Topic Review
NATURAL CLINOPTILOLITE CHARACTERIZATION BY SEM
Clinoptilolite is the most common natural zeolite type. Owing to the very convenient Si/Al ratio, which characterizes this type of zeolite, it can be used for the fabrication of impedimetric water sensors, useful for example for breath rate mesurament and development of low-cost spirometers. The clinoptilolite adsorption properties are related to the large surface development due to the mesoporous structure. The clinoptilolite mesoporosity is a consequence of the unique lamellar texture of this mineral. The clinoptilolite lamellar texture cannot be observed by microscopical techniques like optical microscopy (OM) and scanning electron microscopy (SEM) without adequate sample preparation. Here, a very simple approach to delaminate the clinoptilolite mineral, based on the application of an impulsed compressive stress (hammer), has been used to separate the clinoptilolite single crystals and scanning electron microscopy has been used to visualize and to measure the clinoptilolite crystals.
  • 3.3K
  • 05 Jul 2021
Topic Review
Cinema Therapy
Cinema therapy or movie therapy is a form of expressive therapy - like art, music and dance therapy - for medical and mental health issues. It is also used as a form of self-help. Cinema therapy was created and popularized by Dr. Gary Solomon, the first to write on using movies as therapy. The movement started to catch up again in 2019 with the featured documentary "Calypsonians" by director Anghelo Taylor, unlike the creation of Dr. Gary Solomon, Anghelo Taylor wrote the CinemaTherapy Manifesto, that starts with one simple principle "In order for cinema therapy truly exist the filmmaker must have an internal search, question or problem to solve inside himself but that relates with the rest of humanity or with specific community. Once the filmmaker and his crew engage in the process of filmmaking, they start healing by the revelation and situations that happen along the process of making a film. In the end, the result of that process will be a medicine for all the viewers as human beings. But everything starts with the deep intention that the filmmaker has when making the film"
  • 3.3K
  • 14 Feb 2026
Topic Review
Carpobrotus edulis
Carpobrotus edulis, formerly known as Mesembryanthemum edule L, belongs to the Aizoaceae family of plants. It is a facultative halophytic invasive medicinal and edible succulent plant that is native to South Africa and is distributed worldwide. Hitherto, this plant appears to be mainly known for its ornamental use in decorations, soil stabilization and erosion control, and not for its many potential medicinal and nutritional benefits, thus suggesting its underutilization. This entry presents cogent and comprehensive information on the distribution, ethnomedicinal use, phytochemistry,pharmacology, toxicology, and nutritional value of Carpobrotus edulis and provides the rationale for further pharmacognostic research that will validate its many folkloric medicinal and nutraceutical claims, and promote its standardization into a commercially available product.
  • 3.3K
  • 21 Oct 2020
Topic Review
Remediation of Petroleum Contaminated Soils
Due to the development of the petroleum industrial, numerous petroleum pollutants are discharged into the soil, destroying the structure and properties of the soil, and even endangering the health of plants and humans. Microbial remediation and combined microbial methods remediation of petroleum-contaminated soil are currently recognized remediation technologies, which have the advantages of no secondary pollution, low cost and convenient operation. This entry includes the sources and composition of petroleum pollutants and their harm to soil, plants and humans. Subsequently, the focus is on the mechanism of microbial method and combined microbial methods to degrade petroleum pollutants. Finally, the challenges of the current combined microbial methods are pointed out.
  • 3.3K
  • 28 Sep 2021
Topic Review
Grinding Media in Ball Mills for Mineral Processing
The ball mill is a rotating cylindrical vessel with grinding media inside, which is responsible for breaking the ore particles. Grinding media play an important role in the comminution of mineral ores in these mills.
  • 3.3K
  • 24 Nov 2023
Topic Review
Cairn
A cairn is a man-made pile (or stack) of stones. The word cairn comes from the Scottish Gaelic: càrn [ˈkʰaːrˠn̪ˠ] (plural càirn [ˈkʰaːrˠɲ]). Cairns have been and are used for a broad variety of purposes, from prehistoric times to the present. In modern times, cairns are often erected as landmarks, a use they have had since ancient times. However, since prehistory, they have also been built and used as burial monuments; for defense and hunting; for ceremonial purposes, sometimes relating to astronomy; to locate buried items, such as caches of food or objects; and to mark trails, among other purposes. Cairns are used as trail markers in many parts of the world, in uplands, on moorland, on mountaintops, near waterways and on sea cliffs, as well as in barren deserts and tundras. They vary in size from small stone markers to entire artificial hills, and in complexity from loose conical rock piles to delicately balanced sculptures and elaborate feats of megalithic engineering. Cairns may be painted or otherwise decorated, whether for increased visibility or for religious reasons. An ancient example is the inuksuk (plural inuksuit), used by the Inuit, Inupiat, Kalaallit, Yupik, and other peoples of the Arctic region of North America. Inuksuit are found from Alaska to Greenland. This region, above the Arctic Circle, is dominated by the tundra biome and has areas with few natural landmarks.
  • 3.3K
  • 30 Nov 2022
Topic Review
Metal-Based Nanomaterials
Metal-based nanomaterials could be widely used in biomedical fields, as metal ions are essential in living organisms. Since the particle size of the virus particles ranges from tens to hundreds of nanometers, the surface activity of the metal material is enhanced after the metal is nanosized. It can be used in the inhibition of virus infection.
  • 3.3K
  • 09 Dec 2021
Topic Review
Work
In physics, work is the energy transferred to or from an object via the application of force along a displacement. In its simplest form, it is often represented as the product of force and displacement. A force is said to do positive work if (when applied) it has a component in the direction of the displacement of the point of application. A force does negative work if it has a component opposite to the direction of the displacement at the point of application of the force. For example, when a ball is held above the ground and then dropped, the work done by the gravitational force on the ball as it falls is equal to the weight of the ball (a force) multiplied by the distance to the ground (a displacement). When the force F is constant and the angle between the force and the displacement s is θ, then the work done is given by: [math]\displaystyle{ W = F s \cos{\theta} }[/math] Work is a scalar quantity, so it has only magnitude and no direction. Work transfers energy from one place to another, or one form to another. The SI unit of work is the joule (J), the same unit as for energy.
  • 3.3K
  • 25 Oct 2022
Topic Review Peer Reviewed
Challenges in Sewer System Maintenance
A sewer system is an important infrastructure of every settlement. A sewer system is a set of construction facilities used for the quick removal of wastewater from the humans’ immediate environment and its transport to a wastewater treatment plant or direct discharge into an appropriate recipient. In order for the sewer system to perform its purpose properly, its proper maintenance is required. Maintenance of a sewer system is very demanding since the system is mostly underground which makes it difficult to be accessed and maintained. The maintenance of a sewer system can be preventive (regular) or corrective (reactive). The regular maintenance occurs at certain intervals, whereas the reactive maintenance occurs in the case of some unforeseen event. This paper presents the history of sewer systems, as well as basic and alternative types of sewer systems. Furthermore, challenges that arise during sewer system maintenance and difficulties that maintenance employees face in their work are presented in this paper, as well as the ways in which sewer systems are maintained.
  • 3.3K
  • 20 Jan 2023
Topic Review
Structure-Based Virtual Screening
Molecular docking plays a significant role in early-stage drug discovery, from structure-based virtual screening (VS) to hit-to-lead optimization. VS is a computational approach used to identify chemical structures that are predicted to have particular properties. In drug discovery, it involves computationally searching large libraries of chemical structures to identify those structures that are most likely to bind to a target protein.
  • 3.3K
  • 04 Aug 2022
Topic Review
Fluorescent Polymers Conspectus
The development of luminescent materials is critical to humankind. The Nobel Prizes awarded in 2008 and 2010 for research on the development of green fluorescent proteins and super-resolved fluorescence imaging are proof of this (2014). Fluorescent probes, smart polymer machines, fluorescent chemosensors, fluorescence molecular thermometers, fluorescent imaging, drug delivery carriers, and other applications make fluorescent polymers (FPs) exciting materials. 
  • 3.3K
  • 22 Mar 2022
Topic Review
The Fourth Industrial Revolution
According to Schwab, the word, “revolution”, refers to a radical change, and revolutions occur in the world when new technologies and novel ways of perceiving the world come about, with changes in the economic systems and the social structures of the world. As was noted before, the 4IR is defined as: “Revolution that is blurring the lines between the physical, the digital, and the biological worlds. Massive advances in artificial intelligence (AI), Internet of Things (IoT), robotics, 3D printing, quantum computing, genetic engineering, and various other technologies”. One of the easiest ways of understanding the 4IR is to start gathering knowledge about the First Industrial Revolution, the Second Industrial Revolution, and then the Third Industrial Revolution.
  • 3.3K
  • 06 Apr 2022
Topic Review
Vitamin D in Long COVID-19
Coronavirus disease 2019 (COVID-19) has quickly become a global pandemic. Reports from different parts of the world indicate that a significant proportion of people who have recovered from COVID-19 are suffering from various health problems collectively referred to as “long COVID-19”. Common symptoms include fatigue, shortness of breath, cough, joint pain, chest pain, muscle aches, headaches, and so on. Vitamin D is an immunomodulatory hormone with proven efficacy against various upper respiratory tract infections. Vitamin D can inhibit hyperinflammatory reactions and accelerate the healing process in the affected areas, especially in lung tissue. Moreover, vitamin D deficiency has been associated with the severity and mortality of COVID-19 cases, with a high prevalence of hypovitaminosis D found in patients with COVID-19 and acute respiratory failure. However, no evidence has been found to support a role of vitamin D supplementation in reducing symptoms of long-COVID-19. On the other hand, having a higher vitamin D level before SARS-CoV-2 infection or raising it rapidly at the first symptoms of infection can significantly reduce the risk and severity of COVID-19.
  • 3.3K
  • 29 Apr 2022
Topic Review
E-flux
E-flux is a publishing platform and archive, artist project, curatorial platform, and enterprise founded in 1998. The news digest, events, exhibitions, schools, journal, books, and art projects produced and/or disseminated by e-flux describe strains of critical discourse surrounding contemporary art, culture, and theory internationally. Its monthly publication, e-flux journal, has produced essays commissioned since 2008 about cultural, political, and structural paradigms that inform contemporary artistic production.
  • 3.3K
  • 13 Oct 2022
Topic Review
Biblical Apocrypha
The biblical apocrypha (from the Greek ἀπόκρυφος, apókruphos, meaning "hidden") denotes the collection of apocryphal ancient books found in some editions of Christian Bibles in a separate section between the Old and New Testaments or as an appendix after the New Testament. Some Christian Churches include some or all of the same texts within the body of their version of the Old Testament. Although the term apocrypha had been in use since the 5th century, it was in Luther's Bible of 1534 that the Apocrypha was first published as a separate intertestamental section. To this date, the Apocrypha is "included in the lectionaries of Anglican and Lutheran Churches." Moreover, the Revised Common Lectionary, in use by most mainline Protestants including Methodists and Moravians, lists readings from the Apocrypha in the liturgical kalendar, although alternate Old Testament scripture lessons are provided. The preface to the Apocrypha in the Geneva Bible explained that while these books "were not received by a common consent to be read and expounded publicly in the Church," and did not serve "to prove any point of Christian religion save in so much as they had the consent of the other scriptures called canonical to confirm the same," nonetheless, "as books proceeding from godly men they were received to be read for the advancement and furtherance of the knowledge of history and for the instruction of godly manners." Later, during the English Civil War, the Westminster Confession of 1647 excluded the Apocrypha from the canon and made no recommendation of the Apocrypha above "other human writings", and this attitude towards the Apocrypha is represented by the decision of the British and Foreign Bible Society in the early 19th century not to print it (see below). Today, "English Bibles with the Apocrypha are becoming more popular again" and they are often printed as intertestamental books. Most of the books of the Protestant Apocrypha are called deuterocanonical by Catholics per the Council of Trent and all of them are called anagignoskomena by the Eastern Orthodox per the Synod of Jerusalem. The Anglican Communion accepts "the Apocrypha for instruction in life and manners, but not for the establishment of doctrine (Article VI in the Thirty-Nine Articles)", and many "lectionary readings in The Book of Common Prayer are taken from the Apocrypha", with these lessons being "read in the same ways as those from the Old Testament". The first Methodist liturgical book, The Sunday Service of the Methodists, employs verses from the Apocrypha, such as in the Eucharistic liturgy. The Protestant Apocrypha contains three books (3 Esdras, 4 Esdras and the Prayer of Manasseh) that are accepted by many Eastern Orthodox Churches and Oriental Orthodox Churches as canonical, but are regarded as non-canonical by the Catholic Church and are therefore not included in modern Catholic Bibles.
  • 3.3K
  • 21 Oct 2022
Topic Review
The Blood of Olympus
The Blood of Olympus is an American fantasy-adventure novel written by Rick Riordan, based on Greek and Roman mythology. It was released on October 7, 2014, is the fifth and final novel in The Heroes of Olympus series. It is followed by The Hidden Oracle of The Trials of Apollo. The seven demigods of the Prophecy of Seven—Percy Jackson, Annabeth Chase, Jason Grace, Leo Valdez, Piper McLean, Hazel Levesque, and Frank Zhang—go on their final adventure to defeat Gaea/Terra while Nico di Angelo, Reyna Avila Ramírez-Arellano, and Coach Gleeson Hedge attempt to bring the Athena Parthenos to Camp Half-Blood in order to prevent a war between the Roman and Greek demigods. The novel is narrated in third-person, alternating between the points of view of Jason, Piper, Leo, Reyna, and Nico, making it the first time in the series that someone other than one of the seven demigods of the prophecy is the viewpoint character.
  • 3.3K
  • 24 Nov 2022
Topic Review
Industrial Production of Antibiotics in Fungi
The natural fermentation of antibiotics, along with semi-synthetic and synthetic approaches, is one of the most important methods for their production. The majority of the antibiotic market comes from the fermentation of high-yielding (HY) fungal strains. These strains have been obtained since the 1950s from wild-type (WT) isolates as a result of classical strain improvement (CSI) programs primarily involving multi-round random mutagenesis and screening.
  • 3.3K
  • 19 Dec 2023
Topic Review
Digital Hydraulic Technology
The digital hydraulic technology as a system which controls a discrete fluid with a modulated, discrete, digital signal directly to realize active and intelligent control of the system output. The hydraulic components with such technical characteristics can be defined as digital hydraulic components. The system composed by digital hydraulic components can also be defined as digital hydraulic system. What is more, the essential feature of digital hydraulic technology is intelligent control; technology which can only realize on/off control cannot be classified as digital hydraulic technology.
  • 3.3K
  • 05 May 2022
Topic Review
Laser Melting Deposition
Ceramics and ceramic-reinforced metal matrix composites (CMMCs) demonstrate high wear resistance, excellent chemical inertness, and exceptional properties at elevated temperatures. These characteristics are suitable for their utilization in biomedical, aerospace, electronics, and other high-end engineering industries. The aforementioned performances make them difficult to fabricate via conventional manufacturing methods, requiring high costs and energy consumption. To overcome these issues, laser additive manufacturing (LAM) techniques, with high-power laser beams, were developed and extensively employed for processing ceramics and ceramic-reinforced CMMCs-based coatings. In respect to other LAM processes, laser melting deposition (LMD) excels in several aspects, such as high coating efficiency and lower labor cost. Nevertheless, difficulties such as poor bonding between coating and substrate, cracking, and reduced toughness are still encountered in some LMD coatings.
  • 3.3K
  • 24 Mar 2021
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