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Topic Review
Compounds of Aluminium
Aluminium (or aluminum) combines characteristics of pre- and post-transition metals. Since it has few available electrons for metallic bonding, like its heavier group 13 congeners, it has the characteristic physical properties of a post-transition metal, with longer-than-expected interatomic distances. Furthermore, as Al3+ is a small and highly charged cation, it is strongly polarizing and aluminium compounds tend towards covalency; this behaviour is similar to that of beryllium (Be2+), an example of a diagonal relationship. However, unlike all other post-transition metals, the underlying core under aluminium's valence shell is that of the preceding noble gas, whereas for gallium and indium it is that of the preceding noble gas plus a filled d-subshell, and for thallium and nihonium it is that of the preceding noble gas plus filled d- and f-subshells. Hence, aluminium does not suffer the effects of incomplete shielding of valence electrons by inner electrons from the nucleus that its heavier congeners do. Aluminium's electropositive behavior, high affinity for oxygen, and highly negative standard electrode potential are all more similar to those of scandium, yttrium, lanthanum, and actinium, which have ds2 configurations of three valence electrons outside a noble gas core: aluminium is the most electropositive metal in its group. Aluminium also bears minor similarities to the metalloid boron in the same group; AlX3 compounds are valence isoelectronic to BX3 compounds (they have the same valence electronic structure), and both behave as Lewis acids and readily form adducts. Additionally, one of the main motifs of boron chemistry is regular icosahedral structures, and aluminium forms an important part of many icosahedral quasicrystal alloys, including the Al–Zn–Mg class.
  • 3.3K
  • 07 Nov 2022
Topic Review
Revenge
Revenge is defined as the act of committing a harmful action against a person or group in response to a grievance, be it real or perceived. Francis Bacon described revenge as a kind of "wild justice" that "does... offend the law [and] putteth the law out of office." Primitive justice or retributive justice is often differentiated from more formal and refined forms of justice such as distributive justice and divine judgment.
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  • 11 Oct 2022
Topic Review
Notch Signaling Function in Angiogenesis
The Notch signaling pathway is a major regulator of vascular morphogenesis, managing endothelial response to vascular growth factors, endothelial specialization, establishment and maintenance of vascular identity as venous or arterial and vascular maturation.
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  • 03 Dec 2020
Topic Review
Urinary Tract Infections
Urinary tract infections (UTIs) affect any part of the urinary tract and may spread through the urinary tract towards the urethra, bladder and even the kidneys and they are associated with an increase in morbidity and mortality. UTIs may be resolved spontaneously or treated with antibiotics. However, regular use of antibiotics is related to nephrotoxicity and  produces changes in the intestinal flora, alter immunity and metabolism, and finally, gut bacteria become a reservoir of genes for resistance to antibiotics. Regarding this concern, a new group of molecules called drug conjugates have been proposed as an alternative or a complement to de use of just antibiotics such as a new adjuvant in UTIs therapy called Itxasol©.
  • 3.3K
  • 11 Oct 2021
Topic Review
Seawater Electrolysis
Hydrogen energy, as a clean and renewable energy, has attracted much attention in recent years. Water electrolysis via the hydrogen evolution reaction at the cathode coupled with the oxygen evolution reaction at the anode is a promising method to produce hydrogen. Given the shortage of freshwater resources on the planet, the direct use of seawater as an electrolyte for hydrogen production has become a hot research topic. Direct use of seawater as the electrolyte for water electrolysis can reduce the cost of hydrogen production due to the great abundance and wide availability. Various high-efficiency electrocatalysts have made great progress in seawater splitting and have shown great potential.
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  • 07 Feb 2022
Topic Review
Trace Minerals in Animal Nutrition
Trace mineral refers to the nutritional elements added to production and companion animal diets in micro quantities. They are involved in structural, physiological, catalytic, and regulatory functions in animals. The importance of dietary supplementation of animal feeds with trace minerals is irrefutable, with various forms of both organic and inorganic products commercially available.
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  • 22 Sep 2022
Topic Review
Kelvin–Stokes Theorem
The Kelvin–Stokes theorem, named after Lord Kelvin and George Stokes, also known as the Stokes' theorem, the fundamental theorem for curls or simply the curl theorem, is a theorem in vector calculus on [math]\displaystyle{ \mathbb{R}^3 }[/math]. Given a vector field, the theorem relates the integral of the curl of the vector field over some surface, to the line integral of the vector field around the boundary of the surface. If a vector field [math]\displaystyle{ \mathbf{A} = (P(x, y, z), Q(x, y, z), R(x, y, z)) }[/math] is defined in a region with smooth oriented surface [math]\displaystyle{ \Sigma }[/math] and has first order continuous partial derivatives then: where [math]\displaystyle{ \partial \Sigma }[/math] is boundary of region with smooth surface [math]\displaystyle{ \Sigma }[/math]. The above classical Kelvin-Stokes theorem can be stated in one sentence: The line integral of a vector field over a loop is equal to the flux of its curl through the enclosed surface. The Kelvin–Stokes theorem is a special case of the "generalized Stokes' theorem." In particular, a vector field on [math]\displaystyle{ \mathbb{R}^3 }[/math] can be considered as a 1-form in which case its curl is its exterior derivative, a 2-form.
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  • 02 Nov 2022
Topic Review
Nanomaterials for Water Purification
While water shortage across the world is threatening the well-being of the human community, emerging advanced technologies targeted to address this challenge are promising. In this regard, nanomaterials have played a crucial role.  Nanomaterials, i.e., those materials which have at least one dimension in the 1–100 nm size range, have produced a new generation of technologies for water purification. This includes nanosized adsorbents, nanomembranes, photocatalysts, etc. Stemming from extraordinary structural characteristics and size scale of nanomaterials, the nanostructured membranes/adsorbents enable water purification with a high efficiency in terms of pollutants removal and water permeability, thereby reducing energy consumption and cost. 
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  • 27 Oct 2020
Topic Review
Twinning-Induced Plasticity
Twinning-induced plasticity (TWIP) steel is a second-generation advanced high strength steel grade developed for automotive applications. TWIP steels exhibit an excellent combination of strength and ductility, mainly originating from the activation of deformation twinning.
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  • 23 Feb 2021
Topic Review
On-Site Carwash Wastewater Treatment
The main pollutants in car wash wastewater are detergents, dirt, oil, and grease. Untreated wastewater released into rainwater sewer systems or other water bodies may pollute the water and generate excessive bubble foams, which negatively affects urban appearance. Car washes are divided into mechanical car washes and manual or self-service car washes. In general, car washes have a small operation and scale, occupy limited land, and cannot afford wastewater treatment costs. Therefore, most car washes are not equipped with wastewater treatment facilities. Consequently, the discharge of wastewater from car washes negatively affects the water quality in the surrounding environment and results in wasteful use of water resources. 
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  • 22 Jun 2022
Topic Review
Collections Management (Museum)
Collections management involves the development, storage, and preservation of collections and cultural heritage. The primary goal of collections management is to meet the needs of the individual collector or collecting institution's mission statement, while also ensuring the long-term safety and sustainability of the cultural objects within the collector's care. Collections management, which consists primarily of the administrative responsibilities associated with collection development, is closely related to collections care, which is the physical preservation of cultural heritage. The professions most influenced by collections management include collection managers, registrars, and archivists.
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  • 18 Nov 2022
Topic Review
The beautiful world of biosensors
The biosensors have important role in science of chemical analysis in the field of electrochemical methods. Their application in rapid detection of toxins in types, we consume in our daily lives, is particularly useful for public health. The main characteristics of evaluation of biosensors is the high sensitivity, high selectivity, the quick response and the reusability. Analysis of the real samples need additionally a method of evaluating the rate of recovery that is the fractional difference of signal between real and simulated samples. The advantages of the use of biosensors are part of the easy construction, portability and low cost. The provision of analytical results of biosensors is similar to that of other far more expensive methods of instrumental chemical analysis.
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  • 29 Dec 2021
Topic Review
Intersphincteric Resection for Low Rectal Cancers
Intersphincteric resection is an anus-preserving technique for low rectal cancers described by Schiessel et al. in 1994 as a combination of two techniques: the intersphincteric rectal excision for inflammatory bowel disease and the coloanal anastomosis for low rectal resections.
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  • 08 Oct 2021
Topic Review
Economic Connectivity Processes
The term “economic connectivity” refers to various forms of economic relationships between states or groups of states in the areas of, for example, trade, business activities, finances, technology, and migration. Economic connectivity, a common feature of modern society, is characterized by various political and economic interactions and can be understood in at least two major forms. The first, including transport, communication, and energy infrastructure, is “hard” economic connectivity, while regulatory, institutional, and legal instruments or knowledge, culture, and understanding shape “soft” economic connectivity.
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  • 28 Jun 2022
Topic Review
Triticum aestivum L.
Common wheat (Triticum aestivum), one of the world’s most consumed cereal grains, is known for its uses in baking and cooking in addition to its medicinal uses. As this plant’s medical benefits are enormous and scattered, the pharmacological activities were focused, phytochemistry, and the nutritional values of Triticum aestivum. It is a good source of dietary fiber, resistant starch, phenolic acids, alkylresorcinols, lignans, and diverse antioxidant compounds such as carotenoids, tocopherols and tocotrienols. These constituents provide Triticum aestivum with a wide range of pharmacological properties, including anticancer, antimicrobial, antidiabetic, hypolipemic, antioxidant, laxative, and moisturizing effects.
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  • 05 Jul 2022
Topic Review
Cosmology
Cosmology (from grc κόσμος (kósmos) 'world', and -λογία (-logía) 'study of') is a branch of physics and metaphysics dealing with the nature of the universe. The term cosmology was first used in English in 1656 in Thomas Blount's Glossographia, and in 1731 taken up in Latin by German philosopher Christian Wolff, in Cosmologia Generalis. Religious or mythological cosmology is a body of beliefs based on mythological, religious, and esoteric literature and traditions of creation myths and eschatology. In the science of astronomy it is concerned with the study of the chronology of the universe. Physical cosmology is the study of the observable universe's origin, its large-scale structures and dynamics, and the ultimate fate of the universe, including the laws of science that govern these areas. It is investigated by scientists, such as astronomers and physicists, as well as philosophers, such as metaphysicians, philosophers of physics, and philosophers of space and time. Because of this shared scope with philosophy, theories in physical cosmology may include both scientific and non-scientific propositions, and may depend upon assumptions that cannot be tested. Physical cosmology is a sub-branch of astronomy that is concerned with the Universe as a whole. Modern physical cosmology is dominated by the Big Bang theory, which attempts to bring together observational astronomy and particle physics; more specifically, a standard parameterization of the Big Bang with dark matter and dark energy, known as the Lambda-CDM model. Theoretical astrophysicist David N. Spergel has described cosmology as a "historical science" because "when we look out in space, we look back in time" due to the finite nature of the speed of light.
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  • 01 Jul 2024
Biography
Karl Schwarzschild
Karl Schwarzschild (9 October 1873 – 11 May 1916) was a Germany physicist and astronomer. He was also the father of astrophysicist Martin Schwarzschild. Schwarzschild provided the first exact solution to the Einstein field equations of general relativity, for the limited case of a single spherical non-rotating mass, which he accomplished in 1915, the same year that Einstein first introduced g
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  • 01 Dec 2022
Topic Review
Invasive Seaweeds
According to the International Union for Conservation of Nature (IUCN), an “invasive alien species” is an exotic species that establishes itself in a natural or semi-natural ecosystem or habitat, becoming an agent of change and a threat to diversity native biological. Therefore, invasive species are those capable of successfully reproducing and forming self-sufficient populations in an ecosystem that is not theirs. When this happens, we say that they have "naturalized", which can have disastrous consequences for native (native) species. Some invasive alien species are unable to survive and reproduce on their own, so they end up disappearing from the ecosystem and do not endanger native biodiversity. In this case, they are not considered invasive species, only introduced.
  • 3.3K
  • 25 Nov 2020
Topic Review
Sound Attenuators
A sound attenuator, or duct silencer, sound trap, or muffler, is a noise control acoustical treatment of Heating Ventilating and Air-Conditioning (HVAC) ductwork designed to reduce transmission of noise through the ductwork, either from equipment into occupied spaces in a building, or between occupied spaces. In its simplest form, a sound attenuator consists of an baffle within the ductwork. These baffles often contain sound-absorbing materials. The physical dimensions and baffle configuration of sound attenuators are selected to attenuate a specific range of frequencies. Unlike conventional internally-lined ductwork, which is only effective at attenuating mid- and high-frequency noise, sound attenuators can achieve broader band attenuation in relatively short lengths. Certain types of sound attenuators are essentially a Helmholtz resonator used as a passive noise-control device.
  • 3.3K
  • 27 Oct 2022
Topic Review
IoT Security Challenges and Intrusion Detection Systems
Cybersecurity finds widespread applications across diverse domains, encompassing intelligent industrial systems, residential environments, personal gadgets, and automobiles. This has spurred groundbreaking advancements while concurrently posing persistent challenges in addressing security concerns tied to IoT devices. IoT intrusion detection involves using sophisticated techniques, including deep learning models such as convolutional neural networks (CNNs), recurrent neural networks (RNNs), and anomaly detection algorithms, to identify unauthorized or malicious activities within IoT ecosystems. These systems continuously monitor and analyze network traffic and device behavior, seeking patterns that deviate from established norms. When anomalies are detected, security measures are triggered to thwart potential threats. IoT intrusion detection is vital for safeguarding data integrity, ensuring users’ privacy, and maintaining critical systems’ reliability and safety.
  • 3.3K
  • 11 Dec 2023
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