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Biography
Matt Ridley
Matthew White Ridley, 5th Viscount Ridley DL FRSL FMedSci[1] (born 7 February 1958)[2] is a British journalist and businessman. Ridley is best known for his writings on science, the environment, and economics.[3] He has written several science books including The Red Queen: Sex and the Evolution of Human Nature (1994), Genome (1999), The Rational Optimist: How Prosperity Evolves (2010) and The E
  • 3.0K
  • 29 Nov 2022
Topic Review
Natural Gas Conversion Technologies
Natural gas is a fossil fuel-based energy resource that is abundant in nature. It is a mixture of various components, predominantly methane. Natural gas has wide applications in the industries, residential buildings for heating, electricity generation, as a transportation fuel, and for various commercial purposes. The use of natural gas for electric power generation offers several advantages compared to other fossil fuels.
  • 3.0K
  • 13 Apr 2021
Topic Review
Molecularly Imprinted Polymers-Based Biosensors
The MIP (molecularly imprinted polymer)-based biosensor can be considered an artificial antibody-integrated polymeric active layer that readily sustains stability in challenging testing chemical environments, such as high-temperature limits up to ~300 °C. Since general proteins are usually denatured in irreversible forms higher than ~80 °C, MIP-based biosensors are more stable in storage and even suitable for applications requiring a high-temperature range.
  • 3.0K
  • 08 Mar 2022
Topic Review
Control Strategy for High Speed On/off Valves
Digital hydraulic technology is considered to be a potential solution to replace traditional hydraulic servo control technology in the “Industry 4.0” era. Digital valves mainly consist of incremental digital valves and high speed on/off valves (HSV), of which the former have been abandoned by academia and industry due to its low-frequency and tendency to become out-of-step. 
  • 3.0K
  • 28 Jan 2023
Topic Review
Synthesis of the Coumarin Core
Coumarin compounds are attractive organic compounds with many practical applications. Among them there are compounds with biological activity, pharmaceuticals, agrochemicals, dyes, and optoelectronic materials. For this reason, enormous and continuous attempts were made to develop new synthetic pathways and protocols to facilitate the key cyclization reaction of heterocyclic ring and its regioselective functionalization. Of the numerous proposed reactions for the preparation of coumarins, those based on transition metal catalysts have been frequently used recently. Such processes as intramolecular and intermolecular hydroarylation of alkenes or alkynes can be mentioned among the most effective reactions proceeding via the activation of the C–H bond. Knowledge about the mechanistic foundations of catalytic processes seems to be of significant importance in order to improve them and simplify the conditions. Direct functionalization of the coumarin skeleton seems to be one of the more difficult tasks in recent times.
  • 3.0K
  • 23 Mar 2022
Topic Review
Keychain
A keychain, or keyring, is a small chain, usually made from metal or plastic, that connects a small item to a keyring. The length of a keychain allows an item to be used more easily than if connected directly to a keyring. Some keychains allow one or both ends the ability to rotate, keeping the keychain from becoming twisted, while the item is being used. A keychain can also be a connecting link between a keyring and the belt of an individual. It is usually employed by personnel whose job demands frequent use of keys, such as a security guard, prison officer, janitor, or retail store manager. The chain is often retractable, and therefore may be a nylon rope, instead of an actual metal chain. The chain ensures that the keys remain attached to the individual using them, makes accidental loss less likely, and saves on wear and tear on the pockets of the user.
  • 3.0K
  • 20 Oct 2022
Topic Review
Detection of Image Steganography
As internet traffic grows daily, so does the need to protect it. Network security protects data from unauthorized access and ensures their confidentiality and integrity. Steganography is the practice and study of concealing communications by inserting them into seemingly unrelated data streams (cover media). Investigating and adapting machine learning models in digital image steganalysis is becoming more popular.
  • 3.0K
  • 28 Jun 2023
Topic Review
MEMS Actuators for Fiber-Optic Endoscopes
Endoscopes are used routinely in modern medicine for in-vivo imaging of luminal organs. Technical advances in the micro-electro-mechanical system (MEMS) and optical fields have enabled the further miniaturization of endoscopes, resulting in the ability to image previously inaccessible small-caliber luminal organs, enabling the early detection of lesions and other abnormalities in these tissues. A large number of optical devices have been researched and developed for imaging purposes. Among these, optical coherence tomography (OCT), confocal microscopy (CM), and photoacoustic (PA) imaging are the predominant ones. The size of an endoscope is highly dependent on the actuation and scanning method used to illuminate the target image area. Different actuation methods used in the design of small-sized cantilever-based endoscopes are reviewed in here along with their working principles, advantages and disadvantages, generated scanning patterns, and applications.
  • 3.0K
  • 13 Jan 2021
Topic Review
Blood Flow Modeling
Blood flow modeling consists of using computational techniques to investigate the blood flow behavior in a rapid and accurate fashion. This has become an area of extensive research due to the prevalence of cardiovascular diseases, responsible for a critical number of deaths every year worldwide, most of which are associated with atherosclerosis, a disease that causes unusual hemodynamic conditions in arteries. In the present review,  the application of computational simulations by using different physiological conditions of blood flow, several rheological models, and boundary conditions, were discussed.
  • 3.0K
  • 10 Apr 2021
Topic Review
Microencapsulation
Microencapsulation is a well-known technology for the lipid delivery system. It prevents the oxidation of fatty acids and maintains the quality of lipid after extraction from oil seed and processing. In flaxseed oil, the amount of ω-3 and ω-6 polyunsaturated fatty acids are 39.90–60.42% and 12.25–17.44%, respectively.
  • 3.0K
  • 18 Feb 2021
Topic Review Peer Reviewed
COVID-19 and Peace in Conflict-Affected Areas
The relationship between COVID-19 and peace has been considered from a variety of perspectives. In addition, different empirical studies on the link between the pandemic and peace in conflict-affected areas exist. However, little work has been performed on examining these studies to highlight key findings on the theme of COVID-19 and peace in conflict-affected areas. A conflict-affected area is a country, or part of a country, where widespread violence or armed conflict was present when COVID-19 emerged in December 2019, or that was transitioning from recent armed conflict to peace by the time the disease arose. What do we know, so far, about how peace has been affected by the COVID-19 pandemic in conflict-affected areas? To address this question, this paper begins by recognizing the multidimensionality of peace and clarifying that the main aspects of peace in conflict-affected areas being considered in the article are relations between conflict parties, peace efforts, and peace processes. Afterwards, the paper discusses existing evidence regarding the impact of COVID-19 and state responses to it on these components of peace in conflict-affected areas. The conflict-affected areas considered include Afghanistan, Colombia, Iraq, Israel-Palestine, Libya, Myanmar, Nigeria, South Sudan, Syria, the Philippines, Yemen, and other zones. The central finding of the article is that the existing studies on COVID-19 and peace in conflict-affected areas present mixed findings. On the one hand, the virus generated opportunities for cooperation between conflict parties in some cases, such as in the West Bank and Gaza Strip of Israel-Palestine. However, on the other hand, it created conditions that enabled conflict and impeded peace efforts and processes in many or most conflict-affected areas. The paper explains that two factors that determined how the disease affected peace in conflict-affected and non-conflict-affected areas are the pre-COVID-19 political and socio-economic conditions in an area, and how state and non-state actors responded to the pandemic. The article closes with a summary of the discussion and identification of its major limitations. 
  • 3.0K
  • 28 Sep 2022
Topic Review
Zeolitic Imidazolate Framework
Zeolitic imidazolate frameworks (ZIFs) are a class of metal-organic frameworks that are topologically isomorphic with zeolites. ZIFs are composed of tetrahedrally-coordinated transition metal ions (e.g. Fe, Co, Cu, Zn) connected by imidazolate linkers. Since the metal-imidazole-metal angle is similar to the 145° Si-O-Si angle in zeolites, ZIFs have zeolite-like topologies. As of 2010, 105 ZIF topologies have been reported in the literature. Due to their robust porosity, resistance to thermal changes, and chemical stability, ZIF’s are being investigated for applications such as carbon capture.
  • 3.0K
  • 25 Oct 2022
Topic Review
Protein S-Glutathionylation
S-glutathionylation, the post-translational modification forming mixed disulfides between protein reactive thiols and glutathione, regulates redox-based signaling events in the cell and serves as a protective mechanism against oxidative damage. S-glutathionylation alters protein function, interactions, and localization across physiological processes, and its aberrant function is implicated in various human diseases.
  • 3.0K
  • 10 Nov 2020
Topic Review
Endothelial Cell Dysfunction
Endothelial Cell (EC) dysfunction is one of the first triggers initiating the process of Pulmonary Arterial Hypertension (PAH). EC dysfunction leads to the activation of several cellular signalling pathways in the endothelium, resulting in the uncontrolled proliferation of ECs, pulmonary artery smooth muscle cells, and fibroblasts, and eventually leads to vascular remodelling and the occlusion of the pulmonary blood vessels. Other factors that are related to EC dysfunction in PAH are an increase in endothelial to mesenchymal transition, inflammation, apoptosis, and thrombus formation.
  • 3.0K
  • 18 Jan 2021
Topic Review
Microalgae
Recently, microalgal biotechnology has received increasing interests in producing valuable, sustainable and environmentally friendly bioproducts. The development of economically viable production processes entails resolving certain limitations of microalgal biotechnology, and fast evolving genetic engineering technologies have emerged as new tools to overcome these limitations. 
  • 3.0K
  • 05 May 2022
Topic Review
Thermal Conductivity Measurement
There are a number of possible ways to measure thermal conductivity, each of them suitable for a limited range of materials, depending on the thermal properties and the medium temperature. Three classes of methods exist to measure the thermal conductivity of a sample: steady-state, time-domain, and frequency-domain methods.
  • 3.0K
  • 24 Oct 2022
Topic Review
Wild Turkey
The wild turkey (Meleagris gallopavo) is an upland ground bird native to North America, one of two extant species of turkey, and the heaviest member of the order Galliformes. It is the ancestor to the domestic turkey, which was originally derived from a southern Mexican subspecies of wild turkey (not the related ocellated turkey). Although native to North America, the turkey probably got its name from the domesticated variety being imported to Britain in ships coming from the Levant via Spain. The British at the time therefore associated the wild turkey with the country Turkey and the name prevails. An alternative theory posits that another bird, a guinea fowl native to Madagascar introduced to England by Turkish merchants, was the original source, and that the term was then transferred to the New World bird by English colonizers with knowledge of the previous species.
  • 3.0K
  • 16 Nov 2022
Topic Review
Seven Widely Used Open-Source Platforms
Simulation platforms are critical and indispensable tools for application developments of unmanned aerial vehicles (UAVs) because the UAVs are generally costly, have certain requirements for the test environment, and need professional licensed operators. Thus, developers prefer (or have) to test their applications on simulation platforms before implementing them on real machines. Seven widely used open-source simulation platforms, including Webots, Gazebo, CoppeliaSim, ARGoS, MRDS, MORSE, and USARSim.
  • 3.0K
  • 27 Apr 2023
Topic Review
Machine Learning-Based Forecasting of Renewable Energy
With the increasing penetration of renewable energy sources (RES) into the electricity grid, accurate forecasting of their generation becomes crucial for efficient grid operation and energy management. Traditional forecasting methods have limitations, and thus machine learning (ML) and deep learning (DL) algorithms have gained popularity due to their ability to learn complex relationships from data and provide accurate predictions.
  • 3.0K
  • 27 Apr 2023
Topic Review
Citizenship
Citizenship is a relationship between an individual and a state to which the individual owes allegiance and in turn is entitled to its protection.(quoted) Each state determines the conditions under which it will recognize persons as its citizens, and the conditions under which that status will be withdrawn. Recognition by a state as a citizen generally carries with it recognition of civil, political, and social rights which are not afforded to non-citizens. In general, the basic rights normally regarded as arising from citizenship are the right to a passport, the right to leave and return to the country/ies of citizenship, the right to live in that country and to work there. Some countries permit their citizens to have multiple citizenships, while others insist on exclusive allegiance. A person who does not have citizenship of any state is said to be stateless, while one who lives on state borders whose territorial status is uncertain is a border-lander.
  • 3.0K
  • 18 Nov 2022
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