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Topic Review
Volcanology of Mars
Volcanic activity, or volcanism, has played a significant role in the geologic evolution of Mars. Scientists have known since the Mariner 9 mission in 1972 that volcanic features cover large portions of the Martian surface. These features include extensive lava flows, vast lava plains, and the largest known volcanoes in the Solar System. Martian volcanic features range in age from Noachian (>3.7 billion years) to late Amazonian (< 500 million years), indicating that the planet has been volcanically active throughout its history, and some speculate it probably still is so today. Both Earth and Mars are large, differentiated planets built from similar chondritic materials. Many of the same magmatic processes that occur on Earth also occurred on Mars, and both planets are similar enough compositionally that the same names can be applied to their igneous rocks and minerals. Volcanism is a process in which magma from a planet's interior rises through the crust and erupts on the surface. The erupted materials consist of molten rock (lava), hot fragmental debris (tephra or ash), and gases. Volcanism is a principal way that planets release their internal heat. Volcanic eruptions produce distinctive landforms, rock types, and terrains that provide a window on the chemical composition, thermal state, and history of a planet's interior. Magma is a complex, high-temperature mixture of molten silicates, suspended crystals, and dissolved gases. Magma on Mars likely ascends in a similar manner to that on Earth. It rises through the lower crust in diapiric bodies that are less dense than the surrounding material. As the magma rises, it eventually reaches regions of lower density. When the magma density matches that of the host rock, buoyancy is neutralized and the magma body stalls. At this point, it may form a magma chamber and spread out laterally into a network of dikes and sills. Subsequently, the magma may cool and solidify to form intrusive igneous bodies (plutons). Geologists estimate that about 80% of the magma generated on Earth stalls in the crust and never reaches the surface. As magma rises and cools, it undergoes many complex and dynamic compositional changes. Heavier minerals may crystallize and settle to the bottom of the magma chamber. The magma may also assimilate portions of host rock or mix with other batches of magma. These processes alter the composition of the remaining melt, so that any magma reaching the surface may be chemically quite different from its parent melt. Magmas that have been so altered are said to be "evolved" to distinguish them from "primitive" magmas that more closely resemble the composition of their mantle source. (See igneous differentiation and fractional crystallization.) More highly evolved magmas are usually felsic, that is enriched in silica, volatiles, and other light elements compared to iron- and magnesium-rich (mafic) primitive magmas. The degree and extent to which magmas evolve over time is an indication of a planet's level of internal heat and tectonic activity. The Earth's continental crust is made up of evolved granitic rocks that developed through many episodes of magmatic reprocessing. Evolved igneous rocks are much less common on cold, dead bodies such as the Moon. Mars, being intermediate in size between the Earth and the Moon, is thought to be intermediate in its level of magmatic activity. At shallower depths in the crust, the lithostatic pressure on the magma body decreases. The reduced pressure can cause gases (volatiles), such as carbon dioxide and water vapor, to exsolve from the melt into a froth of gas bubbles. The nucleation of bubbles causes a rapid expansion and cooling of the surrounding melt, producing glassy shards that may erupt explosively as tephra (also called pyroclastics). Fine-grained tephra is commonly referred to as volcanic ash. Whether a volcano erupts explosively or effusively as fluid lava depends on the composition of the melt. Felsic magmas of andesitic and rhyolitic composition tend to erupt explosively. They are very viscous (thick and sticky) and rich in dissolved gases. Mafic magmas, on the other hand, are low in volatiles and commonly erupt effusively as basaltic lava flows. However, these are only generalizations. For example, magma that comes into sudden contact with groundwater or surface water may erupt violently in steam explosions called hydromagmatic (phreatomagmatic or phreatic) eruptions. Erupting magmas may also behave differently on planets with different interior compositions, atmospheres, and gravitational fields.
  • 2.7K
  • 23 Nov 2022
Topic Review
Strategies for Improving Cell-Penetrating Peptides Stability and Delivery
Peptides play an important role in many fields, including immunology, medical diagnostics, and drug discovery, due to their high specificity and positive safety profile. However, for their delivery as active pharmaceutical ingredients, delivery vectors, or diagnostic imaging molecules, they suffer from two serious shortcomings: their poor metabolic stability and short half-life. Major research efforts are being invested to tackle those drawbacks, where structural modifications and novel delivery tactics have been developed to boost their ability to reach their targets as fully functional species.
  • 2.7K
  • 04 Nov 2022
Topic Review
Jerk
In physics, jerk or jolt is the rate at which an object's acceleration changes with respect to time. It is a vector quantity (having both magnitude and direction). Jerk is most commonly denoted by the symbol j and expressed in m/s3 (SI units) or standard gravities per second (g0/s).
  • 2.7K
  • 01 Nov 2022
Topic Review
The Coming of Age of Biosimilars
The first biosimilar, Sandoz’s Omnitrope  (human growth hormone), was approved in 2006 by both the FDA and EMA; it was approved by the FDA under the 505(b)(2) generic product legislation and by the EU as a biosimilar. Later, Sandoz received the first licensing of Zarzio/Zarxio (filgrastim) in 2015; this was the first biosimilar product approved under the 351(k) BLA legislation in the US. Biosimilars have come of age from 2005 to the present, with 84 approvals in the EU and 35 in the US, representing almost 90% of the world market. While the acceptance of biosimilars in the US is catching up with that in the EU, the cost benefits remain elusive due to the high development barrier and complex distribution system involved, mainly in the US. In the EU, the cost of biosimilars has already dropped 70% or more, and interchangeability is a routine in some European jurisdictions, unlike in the US, where a separate regulatory approval is required.
  • 2.7K
  • 27 Apr 2022
Topic Review
Lighting Strategy in Plant Factory with Artificial Light
A plant factory with artificial light (PFAL) is defined as an advanced agricultural production system with a precisely controlled environment, playing an important role in vertical farming and urban food supply. Artificial light is one of the core technologies in PFALs and accounts for a large part of energy consumption; elevating the light utilization efficiency of plants is vital for the sustainable development of PFALs. Meanwhile, the enclosed structure of the plant factory resulted in the independence of its light environment, indicating that the light environment in PFALs can be custom-made. Lighting strategy is an attempt to reprogram the light environmental parameters in unconventional ways, resulting in innovative lighting modes for energy-saving, high-yield, and high-quality production in PFALs. 
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  • 30 May 2022
Topic Review
Gym-Goers’ Motivation to Exercise
To better understand the fitness industry, it is necessary to investigate how appearance and weight management motivations could influence gym-goers’ intention to exercise. Sedentary lifestyle contributes to greater health risks and hence physical exercise motivations becomes an important aspect to study. Beyond its direct managerial implication to fitness trainers and gyms, it would benefit the public sector, educational institutions, health philanthropists and also international organisations interested in the societal wellbeing agenda.
  • 2.7K
  • 15 Jul 2022
Topic Review
Motor Torpedo Boat
User:RMCD bot/subject notice Motor Torpedo Boat (MTB) was the name given to fast torpedo boats by the Royal Navy and the Royal Canadian Navy. The 'motor' in the formal designation, referring to the use of petrol engines, was to distinguish them from the majority of other naval craft that used steam turbines or reciprocating steam engines. The capitalised term is generally used for the Royal Navy (RN) boats and abbreviated to "MTB". During the Second World War, the US Navy built such craft, identified by the hull classification symbol "PT", for "Patrol, Torpedo". German motor torpedo boats of the Second World War were called S-boote (Schnellboote, "fast boats") by the Kriegsmarine and "E-boats" by the Allies. Italian MTBs of this period were known as Motoscafo Armato Silurante ("MAS boats", torpedo armed motorboats). French MTBs were known as vedettes lance torpilles ("torpedo-launching fast boats"). Soviet MTBs were known as торпедные катеры (torpyedniye katyery; "torpedo cutters", often abbreviated as TKA). Romanian MTBs were known as vedete torpiloare ("torpedo fast boats"). After the end of the War in 1945, a number of the Royal Navy's MTBs were stripped and the empty hulls sold for use as houseboats.
  • 2.7K
  • 28 Oct 2022
Topic Review
Job Design
Job design (also referred to as work design or task design) is a core function of industrial and organizational psychology, and refers to the "content and organization of one's work tasks, activities, relationships, and responsibilities" (p. 662). Job design has been linked to a wide range of organizational outcomes, including productivity, safety, and innovation, as well as a range of outcomes that are important to individual workers, such as job satisfaction, personal development, and motivation. Its principles are geared towards how the nature of a person's job affects their attitudes and behavior at work, particularly relating to characteristics such as skill variety and autonomy.
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  • 28 Oct 2022
Topic Review
ABCDE Model of Sarcoidosis Care
The importance of comprehensive care in sarcoidosis is generally acknowledged [12,13]. Here, we describe the ABCDE model, that can be used to structure comprehensive sarcoidosis management in order to improve quality of life and outcomes for patients (Figure 1). This model includes the following components: the Assessment of symptoms and patient’s needs, Backing patients by providing support and education, treatment of Complaints and Comorbidities, Disease-modifying treatment, and the involvement of Extrapulmonary specialists. As disease activity, organ involvement, and patients’ preferences may vary during the disease course, regular reassessment is essential. The ABCDE model can provide guidance to clinicians during the first work-up and follow-up of patients with sarcoidosis.
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  • 23 Oct 2020
Topic Review
Plasan Sand Cat
The SandCat (Hebrew: פלסן קרקל‎) is a composite armored vehicle designed by the then Plasan Sasa (now Plasan) of Israel. The SandCat, which is presented as a single bi-capitalized word, was shown publicly for the first time at AUSA during October 2005. The latest models were shown for the first time at Eurosatory 2018. The SandCat is based on a commercial Ford F-Series chassis. Approximately 700 SandCats have been produced since 2004, and while Plasan has never released complete details, these are known to be in service with at least 16 users across five continents, and in a wide variety of roles that range from Police/internal security to combat/patrol.
  • 2.7K
  • 15 Nov 2022
Topic Review
Coronavirus Invasion
Single-strand RNA (ssRNA) viruses such as the coronavirus family replicate the virus genomes by taking advantage of host cells. For example, after coronavirus approaches the ribosome of the epithelial cells or other host cells, it uses the ribosome of the host cell to replicate polyproteins. The replication and subsequent processes of precursor polyproteins can occur in the epithelial cells. After the coronavirus’ polyproteins are expressed, two enzymes — specifically, coronavirus main proteinase (3CLpro) and the papain-like protease (PLpro) — are thought to be involved in cleaving the polyproteins into smaller products used for replicating new viruses. In order to generate the daughter RNA genome, the coronavirus expresses an RNA-dependent RNA polymerase (RdRp), which is a crucial replicase that catalyzes the synthesis of a complementary RNA strand using the virus RNA template
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  • 28 Oct 2020
Topic Review
Preparation Methods for Large-Area Perovskite Solar Cells
Solar energy is one of the most encouraging, abundant, green, and renewable sources for decreasing or even replacing traditional energy in the future. The energy provided by the sun in one hour is sufficient to supply the Earth’s needs for an entire year. The recent rapid development in perovskite solar cells (PSCs) has led to significant research interest due to their notable photovoltaic performance, currently exceeding 25% power conversion efficiency for small-area PSCs. The materials used to fabricate PSCs dominate the current photovoltaic market, especially with the rapid increase in efficiency and performance.
  • 2.7K
  • 12 Apr 2022
Topic Review
Resources Cycle
Resources cycle means volatility in the resources sector over a period of time based on metrics such as value or production volume. Resource cycles present considerable heterogeneity with differing time lines but generally run from a low point (production, demand or value) through a period of increase, before returning to a comparable low point. Since the turn of the century this concept has driven discourse and research into housing markets, investment opportunities and socioeconomic change in resource towns of a country as the impacts of mining driven change become increasingly pronounced.
  • 2.7K
  • 23 Aug 2021
Topic Review
Nehru Memorial Museum & Library
The Nehru Memorial Museum & Library (NMML) is a museum and library in New Delhi, India , which aims to preserve and reconstruct the history of the Indian independence movement. Housed within the Teen Murti House complex, it is an autonomous institution under the Indian Ministry of Culture, and was founded in 1964 after the death of India's first prime minister, Jawaharlal Nehru. It aims to foster academic research on modern and contemporary history. Today, the Nehru Memorial Library is the world’s leading resource centre on India’s first prime minister. Its archives contain the bulk of Mahatma Gandhi's writings, as well as private papers of C. Rajagopalachari, B. C. Roy, Jayaprakash Narayan, Charan Singh, Sarojini Naidu and Rajkumari Amrit Kaur. In March 2010 it launched a digitization project of its archives, and by June 2011, 867,000 pages of manuscripts and 29,807 photographs had been scanned and 500,000 pages had been uploaded on the digital library website. Amongst noted publications of the NMML are Selected Works of Jawaharlal Nehru, Man of Destiny by Ruskin Bond, Nehru Anthology (1980) and Nehru Anthology. Nehru Memorial Museum & Library has over the years supported scholars and historians across India. Through its fellowship programme, the Nehru Memorial Fellowship, it has funded some of India’s best academics such as Chief Information Commissioner OP Kejriwal. It is also one of the best libraries in Delhi for the social sciences as it has a huge collection on labour related issues in the form of PhD dissertations, reports, books, journals and news papers. On 26 April 2016 a dagger gifted to former prime minister Jawaharlal Nehru by Saudi Arabia was stolen from the Nehru Memorial Museum and Library.
  • 2.7K
  • 11 Nov 2022
Topic Review
Intelligent Packaging for Perishable Products
The preservation of perishable products to maintain their quality is of paramount importance for food safety and security, and is attracting more attention with the increasing concerns on food quality, healthcare and life. Advances in technology and materialsin recent years have led to the development and implementation of intelligent packaging for perishable products that can monitor or evencontrol their quality in supply chain. In this paper, the techniques used in intelligent packaging (i.e., indicators, sensors, and identification technology) and the major printing methods for fabricating electronics (i.e., inkjet printing, screen printing, and gravure printing) are reviewed with a focus on the packagingof perishable products. Althoughthehigh manufacturing costs pose a big challenge for their commercialization and large-scale deployment, it is expected that the technological progressesin printing electronicswill significantly reduce the manufacturing cost of intelligent packaging to a threshold of acceptance by markets and the broad applications of intelligent packaging can facilitate the traction and monitoring of perishable products for better control of the product quality and improved management of supply chain.
  • 2.7K
  • 30 Oct 2020
Topic Review
Neuropsychology of Emotion and Emotion-Regulation
In classic neuropsychological terms, emotion regulation is a higher cortical function that depends on the concerted work of widespread cortical, subcortical, and deep subcortical brain areas. This suggests that we should not only consider the historically relevant question of hemispheric laterality, but also the contribution of specific cognitive skills and brain regions. Thus far, there is emerging evidence to support the link between particular emotion-regulation strategies (e.g., reappraisal and suppression) and well-known basic neuropsychological processes (e.g., inhibition and verbal fluency).
  • 2.7K
  • 04 Sep 2021
Topic Review
Sports Analytics
Sports analytics are a collection of relevant, historical, statistics that can provide a competitive advantage to a team or individual. Through the collection and analyzation of these data, sports analytics inform players, coaches and other staff in order to facilitate decision making both during and prior to sporting events. The term "sports analytics" was popularized in mainstream sports culture following the release of the 2011 film, Moneyball, in which Oakland Athletics General Manager Billy Beane (played by Brad Pitt) relies heavily on the use of analytics to build a competitive team on a minimal budget. There are two key aspects of sports analytics — on-field and off-field analytics. On-field analytics deals with improving the on-field performance of teams and players, including questions such as "which player on the Red Sox contributed most to the team's offense?" or "who is the best wing player in the NBA?", etc. Off-field analytics deals with the business side of sports. Off-field analytics focuses on helping a sport organization or body surface patterns and insights through data that would help increase ticket and merchandise sales, improve fan engagement, etc. Off-field analytics essentially uses data to help rightsholders take decisions that would lead to higher growth and increased profitability. As technology has advanced over the last number of years data collection has become more in-depth and can be conducted with relative ease. Advancements in data collection have allowed for sports analytics to grow as well, leading to the development of advanced statistics and machine learning, as well as sport specific technologies that allow for things like game simulations to be conducted by teams prior to play, improve fan acquisition and marketing strategies, and even understand the impact of sponsorship on each team as well as its fans. Another significant impact sports analytics have had on professional sports is in relation to sport gambling. In depth sports analytics have taken sports gambling to new levels, whether it be fantasy sports leagues or nightly wagers, bettors now have more information at their disposal to help aid decision making. A number of companies and webpages have been developed to help provide fans with up to the minute information for their betting needs.
  • 2.7K
  • 14 Nov 2022
Topic Review
Retinal Prostheses
A retinal prosthesis, also known as a bionic eye, is a device that can be implanted to partially restore vision in patients with retinal diseases that have resulted in the loss of photoreceptors (e.g., age-related macular degeneration and retinitis pigmentosa). There have been major breakthroughs in retinal prosthesis technology, with the creation of numerous types of implants, including epiretinal, subretinal, and suprachoroidal sensors. These devices can stimulate the remaining cells in the retina with electric signals to create a visual sensation.
  • 2.7K
  • 07 Nov 2023
Topic Review
GDL for Proton Exchange Membrane Fuel Cells
Proton exchange membrane fuel cells (PEMFCs) are an attractive type of fuel cell that have received successful commercialization, benefitted from its unique advantages (including an all solid-state structure, a low operating temperature and low environmental impact). In general, the structure of PEMFCs can be regarded as a sequential stacking of functional layers, among which the gas diffusion layer (GDL) plays an important role in connecting bipolar plates and catalyst layers both physically and electrically, offering a route for gas diffusion and drainage and providing mechanical support to the membrane electrode assemblies. 
  • 2.7K
  • 13 Dec 2022
Topic Review
Methods for Enhanced Oil Recovery from Reservoirs
Development systems, placement and choice of operating mode of wells essentially depend on the geological structure of the reservoir, its volume and properties of oils. An important role in this is the construction of a geological model of the production facility. The used hydrodynamic models of development are based on physical laws, about which oil producers sometimes don’t even suspect, and the authors of the models are not always able to convey it to the real producers. 
  • 2.7K
  • 26 Jun 2023
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