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Topic Review
Aspartate in Cell Proliferation and Survival
Aspartate is a precursor for nucleotide synthesis and  is indispensable for cell proliferation. Moreover, the malate–aspartate shuttle plays a key role in redox balance, and a deficit in aspartate can lead to oxidative stress. It is now recognized that aspartate biosynthesis is largely governed by mitochondrial metabolism, including respiration and glutaminolysis in cancer cells. Therefore, under conditions that suppress mitochondrial metabolism, including mutations, hypoxia, or chemical inhibitors, aspartate can become a limiting factor for tumor growth and cancer cell survival.
  • 3.1K
  • 15 Jul 2022
Topic Review
Australian Raven
The Australian raven (Corvus coronoides) is a passerine bird in the genus Corvus native to much of southern and northeastern Australia. Measuring 46–53 centimetres (18–21 in) in length, it has all-black plumage, beak and mouth, as well as strong grey-black legs and feet. The upperparts are glossy, with a purple, blue, or green sheen, and its black feathers have grey bases. The Australian raven is distinguished from the Australian crow species by its throat hackles, which are prominent in adult birds. Older adult individuals have white irises, younger adults have white irises with an inner blue rim, while younger birds have dark brown irises until fifteen months of age, and hazel irises with an inner blue rim around each pupil until age two years and ten months. Nicholas Aylward Vigors and Thomas Horsfield described the Australian raven in 1827, its species name (coronoides) highlighting its similarity with the carrion crow (C. corone). Two subspecies are recognized, which differ slightly in calls and are quite divergent genetically. The preferred habitat is open woodland and transitional zones. It has adapted well to urban environments and is a common city bird in Sydney, Canberra, and Perth. An omnivorous and opportunistic feeder, it eats a wide variety of plant and animal material, as well as food waste from urban areas. In eastern Australia, its range is strongly correlated with the presence of sheep, and it has been blamed for killing lambs. However, this is very rare, and the raven most often scavenges for afterbirth and stillborn animals as well as newborn lamb faeces. The Australian raven is territorial, with pairs generally bonding for life. Breeding takes place between July and September, with almost no variation across its range. The nest is a bowl-shaped structure of sticks sited high in a tree, or occasionally in a man-made structure such as a windmill or other building. File:An audio recording of an Australian Raven (Corvus coronoides).wav
  • 3.1K
  • 21 Nov 2022
Topic Review
Perfume and Flavor Engineering
The Perfumery Ternary Diagram enables us to determine the dominant odor for each perfume composition.
  • 3.1K
  • 29 Jun 2021
Topic Review
Pathophysiology of Coronary Artery Disease in Diabetes Mellitus
Diabetes mellitus (DM) significantly increases the risk of cardiovascular diseases (CVD), all-cause mortality and cardiovascular mortality. According to the Framingham study, patients with DM have a two-fold to four-fold increased risk of developing coronary artery disease (CAD) and myocardial infarction (MI) and a four-fold to six-fold increased risk of developing congestive heart failure (HF). Hyperglycemia represents the main initiating factor in the pathogenesis of diabetic complications.
  • 3.1K
  • 13 May 2022
Topic Review
Pyrolysis of Polystyrene Waste
The manufacturing of polystyrene around the globe has escalated in the past years due to its huge applications in various areas. The perpetual market needs of polystyrene led the polystyrene wastes accretion in the landfill causing environmental deterioration. The soaring need for polystyrene also led to the exhaustion of petroleum, a non-renewable energy source, as polystyrene is a petroleum-derived product.
  • 3.1K
  • 28 Sep 2021
Topic Review
Natural Leaf Fiber
The use of natural fibres has rapidly increased due to their high availability, low density, and renewable capability over synthetic fibre. Natural leaf fibres are easy to extract from the plant (retting process is easy), which offers high stiffness, less energy consumption, less health risk, environment friendly, and better insulation property than the synthetic fibre-based composite. Natural leaf fibre composites have low machining wear with low cost and excellent performance in engineering applications, and hence established as superior reinforcing materials compared to other plant fibres. 
  • 3.1K
  • 26 Apr 2021
Topic Review
Biomechanical Energy Harvesting from the Human Body
Energy harvesters serve as continuous and long-lasting sources of energy that can be integrated into wearable and implantable sensors and biomedical devices. Biomechanical energy is one of the largest categories and one of the most utilized among all other energy sources.
  • 3.1K
  • 28 Nov 2022
Topic Review
Position and Momentum Space
In physics and geometry, there are two closely related vector spaces, usually three-dimensional but in general could be any finite number of dimensions. Position space (also real space or coordinate space) is the set of all position vectors r in space, and has dimensions of length. A position vector defines a point in space. If the position vector of a point particle varies with time it will trace out a path, the trajectory of a particle. Momentum space is the set of all momentum vectors p a physical system can have. The momentum vector of a particle corresponds to its motion, with units of [mass][length][time]−1. Mathematically, the duality between position and momentum is an example of Pontryagin duality. In particular, if a function is given in position space, f(r), then its Fourier transform obtains the function in momentum space, φ(p). Conversely, the inverse Fourier transform of a momentum space function is a position space function. These quantities and ideas transcend all of classical and quantum physics, and a physical system can be described using either the positions of the constituent particles, or their momenta, both formulations equivalently provide the same information about the system in consideration. Another quantity is useful to define in the context of waves. The wave vector k (or simply "k-vector") has dimensions of reciprocal length, making it an analogue of angular frequency ω which has dimensions of reciprocal time. The set of all wave vectors is k-space. Usually r is more intuitive and simpler than k, though the converse can also be true, such as in solid-state physics. Quantum mechanics provides two fundamental examples of the duality between position and momentum, the Heisenberg uncertainty principle ΔxΔp ≥ ħ/2 stating that position and momentum cannot be simultaneously known to arbitrary precision, and the de Broglie relation p = ħk which states the momentum and wavevector of a free particle are proportional to each other. In this context, when it is unambiguous, the terms "momentum" and "wavevector" are used interchangeably. However, the de Broglie relation is not true in a crystal.
  • 3.1K
  • 24 Nov 2022
Topic Review
Red Cabbage Anthocyanins in Smart Food Packaging, Sensors
Anthocyanins, as one of the water-soluble phenolic compounds, are able to generate a wide range of colors (for example, blue, purple, orange, and red) that are widely isolated from flowers, cereals, fruits, and vegetables. In addition, based on the pH values of the solution, anthocyanins can be found in different colors and chemical forms that can monitor food quality parameters, and eventually, keep track of food products over the shelf life period. The reversible color attributes of anthocyanins-rich solutions are associated with the source, composition, and configuration of anthocyanins.
  • 3.1K
  • 28 Apr 2022
Topic Review
Role of NAD+ in Regulating Inflammatory Bowel Disease
Inflammatory bowel disease (IBD), which includes Crohn’s disease (CD) and ulcerative colitis (UC), is a multifactorial systemic inflammatory immune response. Nicotinamide adenine dinucleotide (NAD+) is a co-enzyme involved in cell signaling and energy metabolism. Calcium homeostasis, gene transcription, DNA repair, and cell communication involve NAD+ and its degradation products. In the case of IBD, the maintenance of intestinal homeostasis relies on a delicate balance between NAD+ biosynthesis and consumption.
  • 3.1K
  • 26 Jun 2023
Topic Review
Phytohormones in determining leaf angle
Leaf angel (LA) is regard as the angle between the plant stem and adaxial side of the blade, and is mainly determined by a grass-specfic morphological structure called ligule. As an important plant architecture, LA greatly influences the plant photosynthesis and their planting density, thus leading to yield variation. A large number of studies have revealed the master role of phytochromes in shaping the LA architecture. Our paper broadly discusses the recent advance regarding this topic and proposes several fucture perspectives.
  • 3.1K
  • 27 Jul 2020
Topic Review
Multilevel Inverters for PV Systems
Over the last decade, energy demand from the power grid has increased significantly due to the increasing number of users and the emergence of high-power industries. This has led to a signifi-cant increase in global emissions with conventional energy generation. Therefore, the penetration of renewable energy resources into the power grid has increased significantly. Photovoltaic sys-tems have become the most popular resources as their protentional is enormous, thus, the world-wide installed PV capacity has increased to more than 635 gigawatts (GW), covering approxi-mately 2% of the global electricity demand. Power electronics are an essential part of photovoltaic generation; the drive for efficient power electronic converters is gaining more and more momen-tum. Presently, multilevel inverters (MLI) have become more attractive to researchers compared to two-level inverters due to their abilities to provide lower electromagnetic interference, higher efficiency, and larger DC link voltages. 
  • 3.1K
  • 23 Mar 2021
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
Topic Review
Neurogenic Inflammation
Migraine is a primary headache disorder characterized by a unilateral, throbbing, pulsing headache, which lasts for hours to days, and the pain can interfere with daily activities. It exhibits various symptoms, such as nausea, vomiting, sensitivity to light, sound, and odors, and physical activity consistently contributes to worsening pain. 
  • 3.1K
  • 28 Mar 2022
Topic Review
Taiaha
A taiaha (Māori pronunciation: [ˈtaiaha]) is a traditional weapon of the Māori of New Zealand; a close-quarters staff weapon made from either wood or whalebone, and used for short, sharp strikes or stabbing thrusts with efficient footwork on the part of the wielder. Taiaha are usually between 5 to 6 feet (1.5 to 1.8 m) in length. It has three main parts; the arero (tongue), used for stabbing the opponent and parrying; the upoko (head), the base from which the tongue protrudes; and the ate (liver) or tinana (body), the long flat blade which is also used for striking and parrying.
  • 3.1K
  • 08 Nov 2022
Topic Review
Sex Dimorphism in Body Fat Distribution
Body fat distribution is a well-established predictor of adverse medical outcomes, independent of overall adiposity. Studying body fat distribution sheds insights into the causes of obesity and provides valuable information about the development of various comorbidities. Compared to total adiposity, body fat distribution is more closely associated with risks of cardiovascular diseases.
  • 3.1K
  • 01 Sep 2022
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
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
Biography
Benjamin Hick
Benjamin Hick (1 August 1790 – 9 September 1842) was a successful English civil and mechanical engineer, art collector and patron;[1] his improvements to the steam engine and invention of scientific tools were held in high esteem by the engineering profession,[2] some of Hick's improvements became public property without claiming the patent rights he was entitled to.[3] He was born at Hudder
  • 3.1K
  • 28 Nov 2022
Topic Review
Continuum Robots for Medical Applications
Traditional rigid robot application in the medical field is limited due to the limited degrees of freedom caused by their material and structure. Inspired by trunk, tentacles, and snakes, continuum robot (CR) could traverse confined space, manipulate objects in complex environment, and conform to curvilinear paths in space. The continuum robot has broad prospect in surgery due to its high dexterity, which can reach circuitous areas of the body and perform precision surgery. Recently, many efforts have been done by researchers to improve the design and actuation methods of continuum robots. Several continuum robots have been applied in clinic surgical interventions and demonstrated superiorities to conventional rigid-link robots.
  • 3.1K
  • 13 Jan 2021
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