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Topic Review
Reactive Oxygen Species
Reactive oxygen species (ROS) can directly activate HSCs or induce inflammation or programmed cell death, especially pyroptosis, in hepatocytes, which in turn activates HSCs and fibroblasts to produce ECM proteins.
  • 3.1K
  • 27 Jan 2022
Topic Review
Palm Oil Background
Palm oil plantations cover millions of hectares worldwide, which encompass a significant portion of global trade. Palm oil trees, or Arecaceae, are a genus of stemless, tree-like monocot plants that thrive in the tropics and are extremely valuable to humans and the ecosystem. The African oil palm, or Elaeis guineensis, is the most prominent palm species native to West Africa, cultivated for its oil-rich fruit as a semiwild food source for over 7000 years. The tree produces a profusion of fruit bunches yearly with each containing between 1000 and 3000 fruits.
  • 3.1K
  • 14 Jul 2022
Topic Review
The Factors Impacting Commuting Time
Commuting time holds a significant role in people’s daily routines, representing the duration spent traveling between home and work in the context of daily time use. In the context of rapid urbanization in developing countries, commuting time is increasing. However, excessive commuting time can have significant economic, social, and environmental consequences. For example, longer commuting time hampers per capita income growth and reduces productivity. It also impedes social interactions among residents, leading to a decline in social and economic vitality. Moreover, commuting accounts for a large proportion of urban transportation demand and is closely linked to urban carbon emissions. Additionally, it has detrimental effects on both physical and mental health, as well as the well-being of individuals. Therefore, it is crucial to investigate the factors that influence commuting time in order to mitigate its continual increase.
  • 3.1K
  • 29 Aug 2023
Topic Review
Hybrid Prognostic Approaches of Aircraft Systems and Components
Prognostic and health management (PHM) plays a vital role in ensuring the safety and reliability of aircraft systems. The process entails the proactive surveillance and evaluation of the state and functional effectiveness of crucial subsystems. The principal aim of PHM is to predict the remaining useful life (RUL) of subsystems and proactively mitigate future breakdowns in order to minimize consequences. The achievement of this objective is helped by employing predictive modeling techniques and doing real-time data analysis. The incorporation of prognostic methodologies is of utmost importance in the execution of condition-based maintenance (CBM), a strategic approach that emphasizes the prioritization of repairing components that have experienced quantifiable damage. Multiple methodologies are employed to support the advancement of prognostics for aviation systems, encompassing physics-based modeling, data-driven techniques, and hybrid prognosis. 
  • 3.1K
  • 10 Oct 2023
Topic Review
Mass Concentration
In chemistry, the mass concentration ρi (or γi) is defined as the mass of a constituent mi divided by the volume of the mixture V. For a pure chemical the mass concentration equals its density (mass divided by volume); thus the mass concentration of a component in a mixture can be called the density of a component in a mixture. This explains the usage of ρ (the lower case Greek letter rho), the symbol most often used for density.
  • 3.1K
  • 12 Oct 2022
Topic Review
Strategic Mining Options Optimization
 It is important that the strategic mine plan makes optimum use of available resources and provides continuous quality ore to drive sustainable mining and profitability. This requires the development of a well-integrated strategy of mining options for surface and/or underground mining and their interactions. Understanding the current tools and methodologies used in the mining industry for surface and underground mining options and transitions planning are essential to dealing with complex and deep-seated deposits that are amenable to both surface and underground mining. 
  • 3.1K
  • 29 Jul 2021
Topic Review
Animal Diet Analysis
Diet analysis is a critical content of animal ecology and the diet analysis methods have been constantly improving and updating. Traditional diet analysis methods include direct observation of foraging behavior, the cafeteria diet, microscopic identification of prey remains in fecal and stomach contents. The molecular-based analysis of animal diets has recently become popular, as they confer high resolution and accuracy, which is mainly achieved through the cloning sequencing or the next generation sequencing (NGS) on the amplification of prey DNA in dietary samples.
  • 3.1K
  • 01 Dec 2021
Topic Review
Catalytic Pyrolysis of Plastic Waste
Plastic is a non-degradable material that can persist in the environment for long periods of time. On the other hand, it is a very special material with a great number of advantages: it is affordable, versatile, light, and resistant. Plastic originates from petrochemicals and contains mostly hydrocarbons and some additives, such as antioxidants, flame retardants, and stabilizers, which make the material very bio-undegradable. Pyrolysis can be thermal or catalytic. Thermal pyrolysis requires higher temperatures (from 350 to 900 °C), which can lead to a low molecular weight and low quality products. Gases evolved during pyrolysis have a high calorific value, and could be used in different gas machines and engines for the generation of electricity without any other treatments or modifications. The addition of catalysts overcomes the limitations of thermal pyrolysis, by reducing either the reaction temperature or the time. The addition of catalysts improves conversion, reduces activation energy of pyrolysis, and enhances the fuel quality. The most commonly used catalysts for the pyrolysis of plastics are zeolites, polyciliate components, and clays. Compared to thermal pyrolysis, the catalytic process has the advantage of a lower process temperature, a reduction of solid residues such as carbonized char and volatile fraction, shorter time process, high product selectivity, and high-octane-number products. Zeolite-based catalysts are the best option for the pyrolysis of plastic waste, and for co-pyrolysis of combined plastic waste/biomass.
  • 3.1K
  • 04 Jan 2023
Topic Review
Hydrological Model Uncertainties
Hydrological models are a simplified representation of the natural hydrological processes. These models are developed to understand processes, test hypothesis, and support water resources decision-making. However, as they are simplification of the natural processes, they are inherently uncertain. Their uncertainty primarily stems from their structure, parameter, input and calibration data observations. While parameter and structural uncertainties are related to both data information content and process conceptualizations, input and calibration data observations are a result of data information content. In order to enable an improved process understanding and better decision making, a systemic uncertainty analysis of all of the four sources is critical. 
  • 3.1K
  • 08 Jan 2021
Topic Review
Weismann Barrier
The Weismann barrier has long been regarded as a basic tenet of biology. However, upon close examination of its historical origins and August Weismann's own writings, questions arise as to whether such a status is warranted. As scientific research has advanced, the persistence of the concept of the barrier has left us with the same dichotomies Weismann contended with over 100 years ago: germ or soma, gene or environment, hard or soft inheritance. 
  • 3.1K
  • 30 Jan 2021
Topic Review
Bus Scheduling with Evolutionary Optimization
In public transport operations, vehicles tend to bunch together due to the instability of passenger demand and traffic conditions. Fluctuation of the expected waiting times of passengers at bus stops due to bus bunching is perceived as service unreliability and degrades the overall quality of service. For assessing the performance of high-frequency bus services, transportation authorities monitor the daily operations via Transit Management Systems (TMS) that collect vehicle positioning information in near real-time. This work explores the potential of using Automated Vehicle Location (AVL) data from the running vehicles for generating bus schedules that improve the service reliability and conform to various regulatory constraints. The computer-aided generation of optimal bus schedules is a tedious task due to the nonlinear and multi-variable nature of the bus scheduling problem. For this reason, this work develops a two-level approach where (i) the regulatory constraints are satisfied and (ii) the waiting times of passengers are optimized with the introduction of an evolutionary algorithm. This work also discusses the experimental results from the implementation of such an approach in a bi-directional bus line operated by a major bus operator in northern Europe.
  • 3.1K
  • 29 Oct 2020
Topic Review
Sodium Cyclamate
Sodium cyclamate (sweetener code 952) is an artificial sweetener. It is 30–50 times sweeter than sucrose (table sugar), making it the least potent of the commercially used artificial sweeteners. It is often used with other artificial sweeteners, especially saccharin; the mixture of 10 parts cyclamate to 1 part saccharin is common and masks the off-tastes of both sweeteners. It is less expensive than most sweeteners, including sucralose, and is stable under heating. Safety concerns led to it being banned in a few countries, though the European Union considers it safe.
  • 3.1K
  • 08 Oct 2022
Topic Review
Commonwealth
A commonwealth is a traditional English term for a political community founded for the common good. Historically it has sometimes been synonymous with "republic". The noun "commonwealth", meaning "public welfare general good or advantage", dates from the 15th century. Originally a phrase (the common-wealth or the common wealth – echoed in the modern synonym "public wealth") it comes from the old meaning of "wealth", which is "well-being", and is itself a loose translation of the Latin res publica (republic). The term literally meant "common well-being". In the 17th century, the definition of "commonwealth" expanded from its original sense of "public welfare" or "commonweal" to mean "a state in which the supreme power is vested in the people; a republic or democratic state". The term evolved to become a title to a number of political entities. Three countries – Australia , the Bahamas, and Dominica – have the official title "Commonwealth", as do four U.S. states and two U.S. territories. Since the early 20th century, the term has been used to name some fraternal associations of nations, most notably the Commonwealth of Nations, an organization primarily of former territories of the British Empire, which is often referred to as simply "the Commonwealth".
  • 3.1K
  • 10 Nov 2022
Topic Review
Book of Dzyan
The Book of Dzyan (comprising the Stanzas of Dzyan) is a reputedly ancient text of Tibetan origin. The Stanzas formed the basis for The Secret Doctrine (1888), one of the foundational works of the theosophical movement, by Helena Petrovna Blavatsky.
  • 3.1K
  • 21 Nov 2022
Topic Review
Byproduct Oxygen for Green Hydrogen Electrolysis
Water electrolysis for hydrogen production with renewable electricity is regularly studied. The inclusion of byproduct electrolytic oxygen capture and sale is of interest for parallel decarbonisation efforts elsewhere in the industry and could contribute to reducing green hydrogen costs. A deterministic hydrogen electrolysis system model is constructed to compare oxygen inclusion/exclusion scenarios. This uses wind and solar-PV electricity generation timeseries, a power-dependent electrolysis model to determine the energy efficiency of gas yield, and power allocation for gas post-processing energy within each hourly timestep. This maintains a fully renewable (and therefore low/zero carbon) electricity source for electrolysis and gas post-processing. The model is validated (excluding oxygen) against an existing low-cost GW-scale solar-hydrogen production scenario and an existing hydrogen production costs study with offshore wind generation at the multi-MW scale. For both comparisons, oxygen inclusion is then evaluated to demonstrate both the benefits and drawbacks of capture and utilisation, for different scenario conditions, and high parameter sensitivity can be seen regarding the price of renewable electricity.
  • 3.1K
  • 18 Jan 2024
Topic Review
Pegasus
Pegasus, the winged horse of Greek mythology, is a prominent constellation in the northern sky, known for its distinctive "Great Square" asterism. As one of the 48 constellations cataloged by the ancient Greek astronomer Ptolemy, Pegasus has a rich cultural and astronomical significance. Its association with the mythical creature Pegasus, ridden by heroes such as Perseus and Bellerophon, adds to its allure and makes it a captivating subject for stargazers.
  • 3.1K
  • 15 Mar 2024
Topic Review
Coffee Berry Borer (Hypothenemus hampei)
Coffee berry borer (CBB) is the most serious insect pest of coffee worldwide, causing more than US$500M in damages annually. Reduction in the yield and quality of coffee results from the adult female CBB boring into the coffee fruit and building galleries for reproduction, followed by larval feeding on the bean itself.
  • 3.1K
  • 23 Dec 2020
Topic Review
Optical Biomedical Sensors
The optical biomedical sensor industry has grown enormously over the past few years and is expected to grow more in the forthcoming days because of the extensive need for point-of-care testing devices. Researchers all over the world are working on the implementation of highly sensitive, reliable, portable, and inexpensive biomedical appliances, which can revolutionize this market. Optical biosensing is a vast topic, and numerous optical sensing techniques have been presented over the years.These techniques and corresponding technological platforms enabling the manufacturing of optical biomedical sensors of different types.the most representative cases are integrated optical biosensors, vertical grating couplers, plasmonic sensors, surface plasmon resonance optical fiber biosensors, and metasurface biosensors, Photonic crystal-based biosensors, thin metal films biosensors, and fiber Bragg grating biosensors，these optical biomedical sensors might enable the identification of symptoms of deadly illnesses in their early stages; thus, potentially saving a patient’s life. 
  • 3.1K
  • 05 May 2021
Topic Review
Lake Taupo
Lake Taupo, often spelled Taupō, is a lake in the North Island of New Zealand. It is in the caldera of the Taupo Volcano. The lake is the namesake of the town of Taupō, which sits on a bay in the lake's north-eastern shore. With a surface area of 616 square kilometres (238 sq mi), it is the largest lake by surface area in New Zealand, and the second largest freshwater lake by surface area in geopolitical Oceania after Lake Murray in Papua New Guinea. Motutaiko Island lies in the south east area of the lake. Lake Taupo has a perimeter of approximately 193 kilometres and a maximum depth of 186 metres. It is drained by the Waikato River (New Zealand's longest river), and its main tributaries are the Waitahanui River, the Tongariro River, and the Tauranga Taupo River. It is a noted trout fishery with stocks of introduced brown and rainbow trout. The level of the lake is controlled by Mercury Energy, the owner of the eight hydroelectric dams on the Waikato River downstream of Lake Taupo, using gates built in 1940–41. The gates are used to reduce flooding, conserve water and ensure a minimum flow of 50 m3/s (1,800 cu ft/s) in the Waikato River. The resource consent allows the level of the lake to be varied between 355.85 and 357.25 metres (1,167.5 and 1,172.1 ft) above sea level.
  • 3.1K
  • 08 Nov 2022
Topic Review
Bambara Groundnut for Food Security
Bambara groundnut is one such imperative and neglected legume crop that contributes positively to improving global food and nutrient safety. As a “complete food”, this crop has recently been treated as a new millennium crop, and furthermore, it is more adjusted to poor soil and climatic conditions than other dominant crops. Bambara groundnut is a repository of vital nutrients that provides carbohydrates, crucial amino acids, proteins, and energy as well as minerals and vitamins to developed and low-income countries where animal proteins are not readily available. 
  • 3.1K
  • 28 May 2021
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