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Topic Review
Oleaginous Yeasts
The production of lipids from oleaginous yeasts involves several stages starting from cultivation and lipid accumulation, biomass harvesting and finally lipids extraction. However, the complex and relatively resistant cell wall of yeasts limits the full recovery of intracellular lipids and usually solvent extraction is not sufficient to effectively extract the lipid bodies. A pretreatment or cell disruption method is hence a prerequisite prior to solvent extraction. In general, there are no recovery methods that are equally efficient for different species of oleaginous yeasts.
  • 3.0K
  • 08 Feb 2021
Topic Review
Skin Tissue Engineering Application
Skin tissue engineering has made remarkable progress in wound healing treatment with the advent of newer fabrication strategies using natural/synthetic polymers and stem cells. Currently, stem cells and biomaterials are popularly used in the skin tissue engineering approach in different wound healing treatments. In skin tissue engineering application, stem cell facilitates in the regeneration of disintegrated tissue. Whereas, biomaterials serve as a platform to improve the engraftment of implanted cells and facilitate the function of exogenous cells by mimicking the tissue microenvironment. Hence, the combination and synergistic effect of biomaterials and stem cells have the potential to broaden the application of skin tissue engineering in wound healing treatment therapies.  
  • 3.0K
  • 19 May 2021
Topic Review
Elasticity
In physics and materials science, elasticity is the ability of a body to resist a distorting influence and to return to its original size and shape when that influence or force is removed. Solid objects will deform when adequate loads are applied to them; if the material is elastic, the object will return to its initial shape and size after removal. This is in contrast to plasticity, in which the object fails to do so and instead remains in its deformed state. The physical reasons for elastic behavior can be quite different for different materials. In metals, the atomic lattice changes size and shape when forces are applied (energy is added to the system). When forces are removed, the lattice goes back to the original lower energy state. For rubbers and other polymers, elasticity is caused by the stretching of polymer chains when forces are applied. Hooke's law states that the force required to deform elastic objects should be directly proportional to the distance of deformation, regardless of how large that distance becomes. This is known as perfect elasticity, in which a given object will return to its original shape no matter how strongly it is deformed. This is an ideal concept only; most materials which possess elasticity in practice remain purely elastic only up to very small deformations, after which plastic (permanent) deformation occurs. In engineering, the elasticity of a material is quantified by the elastic modulus such as the Young's modulus, bulk modulus or shear modulus which measure the amount of stress needed to achieve a unit of strain; a higher modulus indicates that the material is harder to deform. The SI unit of this modulus is the pascal (Pa). The material's elastic limit or yield strength is the maximum stress that can arise before the onset of plastic deformation. Its SI unit is also the pascal (Pa).
  • 3.0K
  • 06 May 2023
Biography
James Heppelmann
James E. Heppelmann (born September 4, 1964) [1] is an American engineer and businessman. He is the chief executive officer (CEO) of PTC (software company) (formerly Parametric Technology) a multinational software company he joined in January of 1998 as Senior Vice President Windchill, Parametric Technology Corp. Heppelmann grew up in rural Minnesota on a small dairy farm with his seven sibli
  • 3.0K
  • 29 Dec 2022
Topic Review
Range Extender (Vehicle)
A range extender vehicle is a battery electric vehicle that includes an auxiliary power unit (APU) known as a 'range extender'. The range extender drives an electric generator which charges a battery which supplies the vehicle's electric motor with electricity. This arrangement is known as a series hybrid drivetrain. The most commonly used range extenders are internal combustion engines, but fuel-cells or other engine types can be used. Range extender vehicles are also referred to as extended-range electric vehicles (EREV), range-extended electric vehicles (REEV), and range-extended battery-electric vehicle (BEVx) by the California Air Resources Board (CARB). The key function of the range extender is to increase the vehicle's range. Range autonomy is one of the main barriers for the commercial success of electric vehicles, and extending the vehicle's range when the battery is depleted helps alleviate range anxiety. A range extending vehicle design can also reduce the consumption of the range extending fuel (such as gasoline) by using the primary fuel (such as battery power), while still maintaining the driving range of a single fuel vehicle powered by a range extending fuel such as gasoline. The range extending fuel is generally considered to be less environmentally and economically friendly to use than the primary fuel source, so the vehicle control system gives preference to using the primary fuel if it's available. However, due to range limitations with the primary fuel source, the range extending fuel allows the vehicle to get many of the cost and environmental benefits of the primary fuel, while maintaining the full driving range of the range extending fuel source. For example, in the Chevy Volt, battery power from the electric grid can be cheaper and more environmentally sustainable than burning gasoline (depending on the electric generation source), but due to the trade offs between the range of a pure electric vehicle and its battery size, adding the range extending gasoline is considered by many to be good compromise to give the Chevy Volt a significantly greater driving range. How many benefits are derived from using the primary fuel however depend on how the vehicles are driven. For example, a first generation Chevy Volt will operate 100% on battery power from the electric grid for the first 60 km (37 miles), while the second generation Volt will operate on 100% battery power for the first 85 km (53 miles) when fully recharged between trips. However, if the same Chevy Volt is driven for hundreds of miles a day it will require significant gasoline as the battery will be quickly depleted. Using the gasoline engine to generate power for the motors, the economy ratings are 6.4 L/100 km (37 mpg‑US) and 5.6 L/100 km (42 mpg‑US) for the different generation models. Therefore, it is critical to understand the driving patterns of the average commuter to fully understand the impact these range extending vehicles will have in the real world. Many range extender vehicles, including the Chevrolet Volt and the BMW i3, are able to charge their batteries from the grid as well as from the range extender, and therefore are a type of plug-in hybrid electric vehicle (PHEV). When a range extender uses conventional fuels they can re-fuel at regular fuel stations, which provides them with a similar driving range to conventional automobiles. As an REEV is only propelled by the electric motor it can do away with the weight and cost associated with the gearbox transmission system typically used in internal combustion engine cars. Further, as the range extender does not need to increase or decrease output in line with the power needs of the vehicle (this task is handled by the electric motor) the range extender can be sized to satisfy the vehicle's average power requirement rather than its peak power requirement (such as when accelerating). The range extender can also operate much closer to its most efficient rotational speed. These design features allow an REEV to convert fossil fuel energy to electric power and vehicle motion very efficiently.
  • 3.0K
  • 28 Oct 2022
Topic Review
Oscillatory Spinning Drop Interfacial Rheology
The oscillatory spinning drop method has been proven recently to be an accurate technique to measure dilational interfacial rheological properties. It is the only available equipment for measuring dilational moduli in low interfacial tension systems, as is the case in applications dealing with surfactant-oil-water three-phase behavior like enhanced oil recovery, crude oil dehydration, or extreme microemulsion solubilization. Different systems can be studied with this method with the lower density phase as the spinning drop, i.e, oil-in-water, microemulsion-in-water, oil-in-microemulsion, including systems with the presence of complex natural surfactants like asphaltene aggregates or particles. The technique allows studying the characteristics and properties of water/oil interfaces, particularly when the oil contains asphaltenes and when surfactants are present. We have found that using the oscillating spinning drop method to measure interfacial rheology properties can help make precise measurements in a reasonable amount of time. This is of significance when systems with long equilibration times, e.g., asphaltene or high molecular weight surfactant-containing systems are measured, or with systems formulated with a demulsifier which is generally associated with optimum formulation and a low interfacial tension.
  • 3.0K
  • 08 Sep 2024
Topic Review
Agarose Hydrogels
Numerous compounds present in the ocean are contributing to the development of the biomedical field. Agarose, a polysaccharide derived from marine red algae, plays a vital role in biomedical applications because of its reversible temperature-sensitive gelling behavior, excellent mechanical properties, and high biological activity. Natural agarose hydrogel has a single structural composition that prevents it from adapting to complex biological environments.
  • 3.0K
  • 26 May 2023
Biography
Beatrice Wood
Beatrice Wood (March 3, 1893 – March 12, 1998) was an United States artist and studio potter involved in the Avant Garde movement in the United States; she founded and edited The Blind Man magazine in New York City with French artist Marcel Duchamp and writer Henri-Pierre Roché in 1917.[1] She had earlier studied art and theater in Paris, and was working in New York as an actress. She later w
  • 3.0K
  • 25 Nov 2022
Topic Review
DNS Tunnelling Detection
The Domain Name System (DNS) protocol is fundamental to the operation of the Internet with the primary purpose of translating domain names to IP addresses. This important service facilitates access to the Internet by using website names or any arbitrary domain names. The DNS protocol communicates internal requests to external remote servers and creates a landscape for attackers to perform malicious activities such as stealing credentials and sensitive data. One of the most effective DNS attack types is DNS tunnelling, where the attacker creates a tunnel between the client’s network and the attacker’s machine, utilising command and control channels to obscure data and bypass the firewall and intrusion detection systems.
  • 3.0K
  • 01 Mar 2024
Topic Review
Globalization of the Football Transfer Market
The football transfer market has been affected by the increased freedom of movement, trade and communications between different countries since the 1990s. This globalization of the transfer market has impacted the way in which football clubs trade with one another and the relationship between players and their clubs. When professional leagues were first founded, there were significant restrictions preventing footballers from joining whomever they liked. These limitations were put in place by both the clubs these players were tied to, and the leagues in which they played. International labor movement regulations and the difficulties of scouting less developed nations also hindered the development of a liberalized transfer market.
  • 3.0K
  • 11 Nov 2022
Topic Review Peer Reviewed
Residential Segregation
Residential segregation refers to the disproportionate distribution of population groups across a geographical area. Groups can be segregated on the basis of any characteristic (such as occupation, income, religion, age or ethnicity) and at any geographical scale. In most cases, segregation is, however, measured with regard to residential areas of a city. The extent of the unequal distribution of selected characteristics can be expressed by different statistical measures. Sociologists, economists and demographers have long studied how social groups tend to be differentiated in residential space and developed a broad range of explanations. As a consequence, segregation has been explained by a variety of theories, which are discussed in this paper. The topics examined by empirical research include temporal dynamics, geographical patterns, societal causes and effects on life chances. This entry focuses on major conceptual facts regarding residential segregation and only marginally discusses the methodological issues connected with its measurement.
  • 3.0K
  • 02 Nov 2023
Topic Review
Recovery of Palladium from the Spent Automobile Catalysts
The spent automobile catalysts (SAC) is the major secondary source of palladium and the production of SAC is increasing rapidly over years. The price of palladium keeps rising over the years, which demonstrates its preciousness and urgent industrial demand. Recovering palladium from the spent automobile catalysts benefits a lot from economic and environmental protection aspects.  Hydrometallurgical methods such as chloride leaching with oxidants possess a high selectivity of palladium and low consumption of energy, and are cost-effective and flexible for different volume feeds compared with pyrometallurgical methods. The recovery ratios of palladium and other platinum-group metals should be the focus of competition since their prices have been rapidly increased over the years, and hence more efficient extractants with high selectivity of palladium even in the complexed leachate should be proposed in the future. 
  • 3.0K
  • 12 Apr 2022
Topic Review
Non-Mechanical Hybrid Hydrogen Compression
Non-mechanical hybrid hydrogen compressors consists of a first electrochemical compression stage followed by a second one based on the adsorption-desorption of hydrogen on microporous materials. They allow compressing hydrogen up to 70 MPa. Non-mechanical hybrid hydrogen compressors can be a valid alternative to the mechanical compressors. 
  • 3.0K
  • 29 Jun 2020
Topic Review
Probabilistic Optimization Techniques in Smart Power System
Stochastic programming is used to solve optimization problems in which the majority of the parameters are probabilistic. Probabilistic optimization can make efficient use of information, both in terms of selecting evaluation points and the message they convey. It can handle many sorts of noise and adapts to various aspects of optimization issues. Unlike deterministic optimization, probabilistic optimization techniques discover the best solution for data with randomness.
  • 3.0K
  • 17 Feb 2022
Biography
Gustav Otto
Gustav Otto (12 January 1883 – 28 February 1926) was a German aircraft and aircraft engine designer and manufacturer. Gustav was born in Cologne to Nikolaus August Otto, the founder of N. A. Otto & Cie. and inventor of the four-stroke internal combustion engine. It is therefore regarded that his interest in engines, specifically aircraft and the manufacture thereof, was something he inherited
  • 3.0K
  • 22 Nov 2022
Topic Review
Chloroplasts in Plant Stress Responses
The chloroplast has a central position in oxygenic photosynthesis and primary metabolism. In addition to these functions, the chloroplast has recently emerged as a pivotal regulator of plant responses to abiotic and biotic stress conditions. Chloroplasts have their own independent genomes and gene-expression machinery and synthesize phytohormones and a diverse range of secondary metabolites, a significant portion of which contribute the plant response to adverse conditions.
  • 3.0K
  • 05 Jan 2022
Topic Review
Bacterial Resistance to Antimicrobial Agents
Bacterial pathogens as causative agents of infection constitute an alarming concern in the public health sector. In particular, bacteria with resistance to multiple antimicrobial agents can confound chemotherapeutic efficacy towards infectious diseases. Multidrug-resistant bacteria harbor various molecular and cellular mechanisms for antimicrobial resistance. These antimicrobial resistance mechanisms include active antimicrobial efflux, reduced drug entry into cells of pathogens, enzymatic metabolism of antimicrobial agents to inactive products, biofilm formation, altered drug targets, and protection of antimicrobial targets. These microbial systems represent suitable focuses for investigation to establish the means for their circumvention and to reestablish therapeutic effectiveness.
  • 3.0K
  • 01 Aug 2022
Topic Review
Fintech and Financial Risks
Fintech is the combination of the words of finance and technology. It is literally understood as the application of technology in the financial field. As the financial innovation brought by technology, Fintech can change traditional financial markets, financial institutions and financial services, and create emerging business models, applications, processes, and products.
  • 3.0K
  • 05 Aug 2022
Topic Review
Ruby Pistol
The self-loading Ruby pistol is best known as a French World War I sidearm, the Pistolet Automatique de 7 millim.65 genre "Ruby". A very international piece of weaponry, it was closely modeled after John Browning's M1903 design produced by the Belgian Fabrique Nationale de Herstal, and was produced by over 50 Spanish companies, but primarily by the Spanish Gabilondo y Urresti firm (the official "Gabilondo Ruby"). It was decommissioned in 1958, more than a decade after World War II was brought to an end, and was subsequently replaced.
  • 3.0K
  • 20 Oct 2022
Topic Review
Hydrogen Fuel Internal-Combustion Engines
To achieve the goals of low carbon emission and carbon neutrality, some urgent challenges include the development and utilization of low-carbon or zero-carbon internal combustion engine fuels. Hydrogen, as a clean, efficient, and sustainable fuel, has the potential to meet the abovementioned challenges. Thereby, hydrogen internal combustion engines have been attracting attention because of their zero carbon emissions, high thermal efficiency, high reliability, and low cost.
  • 3.0K
  • 28 Oct 2022
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