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Topic Review
Landslide Mitigation
Landslide mitigation refers to mass movement of rocks and other man-made activities on slopes with the goal of lessening the effect of landslides. Landslides can be triggered by many, sometimes concomitant causes. In addition to shallow erosion or reduction of shear strength caused by seasonal rainfall, landslides may be triggered by anthropic activities, such as adding excessive weight above the slope, digging at mid-slope or at the foot of the slope. Often, individual phenomenon join together to generate instability over time, which often does not allow a reconstruction of the evolution of a particular landslide. Therefore, landslide hazard mitigation measures are not generally classified according to the phenomenon that might cause a landslide. Instead, they are classified by the sort of slope stabilization method used: Each of these methods varies somewhat with the type of material that makes up the slope.
  • 1.9K
  • 29 Sep 2022
Topic Review
Steady State
In chemistry, a steady state is a situation in which all state variables are constant in spite of ongoing processes that strive to change them. For an entire system to be at steady state, i.e. for all state variables of a system to be constant, there must be a flow through the system (compare mass balance). A simple example of such a system is the case of a bathtub with the tap running but with the drain unplugged: after a certain time, the water flows in and out at the same rate, so the water level (the state variable Volume) stabilizes and the system is in a steady state. The steady state concept is different from chemical equilibrium. Although both may create a situation where a concentration does not change, in a system at chemical equilibrium, the net reaction rate is zero (products transform into reactants at the same rate as reactants transform into products), while no such limitation exists in the steady state concept. Indeed, there does not have to be a reaction at all for a steady state to develop. The term steady state is also used to describe a situation where some, but not all, of the state variables of a system are constant. For such a steady state to develop, the system does not have to be a flow system. Therefore, such a steady state can develop in a closed system where a series of chemical reactions take place. Literature in chemical kinetics usually refers to this case, calling it steady state approximation. In simple systems the steady state is approached by state variables gradually decreasing or increasing until they reach their steady state value. In more complex systems state variable might fluctuate around the theoretical steady state either forever (a limit cycle) or gradually coming closer and closer. It theoretically takes an infinite time to reach steady state, just as it takes an infinite time to reach chemical equilibrium. Both concepts are, however, frequently used approximations because of the substantial mathematical simplifications these concepts offer. Whether or not these concepts can be used depends on the error the underlying assumptions introduce. So, even though a steady state, from a theoretical point of view, requires constant drivers (e.g. constant inflow rate and constant concentrations in the inflow), the error introduced by assuming steady state for a system with non-constant drivers may be negligible if the steady state is approached fast enough (relatively speaking).
  • 1.9K
  • 14 Oct 2022
Topic Review
Forest Raven
The forest raven (Corvus tasmanicus), also commonly known as the Tasmanian raven, is a passerine bird in the family Corvidae native to Tasmania and parts of southern Victoria, such as Wilsons Promontory and Portland. Populations are also found in parts of New South Wales, including Dorrigo and Armidale. Measuring 50–53 cm (20–21 in) in length, it has all-black plumage, beak and legs. As with the other two species of raven in Australia , its black feathers have grey bases. Adults have white irises; younger birds have dark brown and then hazel irises with an inner blue rim. New South Wales populations are recognised as a separate subspecies C. tasmanicus boreus, but appear to be nested within the Tasmanian subspecies genetically. The forest raven lives in a wide variety of habitats in Tasmania but is restricted to more closed forest on mainland Australia. Breeding takes place in spring and summer, occurring later in Tasmania than in New South Wales. The nest is a bowl-shaped structure of sticks sited high in a tree. An omnivorous and opportunistic feeder, it eats a wide variety of plant and animal material, as well as food waste from urban areas and roadkill. It has been blamed for killing lambs and poultry and raiding orchards in Tasmania, and is unprotected under Tasmanian legislation. The forest raven is sedentary, with pairs generally bonding for life and establishing permanent territories.
  • 1.9K
  • 24 Oct 2022
Topic Review
Histone Deacetylase Inhibitors
Histone deacetylases (HDACs) are key components of the epigenetic machinery controlling gene expression. They are involved in chromatin remodeling events via post-translational histone modifications but may also act on nonhistone proteins, influencing many fundamental cellular processes. Due to the key involvement of HDACs in serious human pathologies, including cancer, HDAC inhibitors (HDACis) have received increased attention in recent years. It is known that marine invertebrates produce significant amounts of secondary metabolites showing active pharmacological properties and an extensive spectrum of biomedical applications. Some of these compounds possess HDACi properties.
  • 1.9K
  • 11 Dec 2020
Topic Review
Mentalism (Discrimination)
Mentalism or sanism describes discrimination and oppression against a mental trait or condition a person has, or is judged to have. This discrimination may or may not be characterized in terms of mental disorder or cognitive impairment. The discrimination is based on numerous factors such as stereotypes about neurodivergence, for example Aspergers, learning disorders, ADHD, bipolar, schizophrenia, and personality disorders, specific behavioral phenomena such as stuttering and tics, or intellectual disability. Like other forms of discrimination such as sexism and racism, mentalism involves multiple intersecting forms of oppression, complex social inequalities and imbalances of power. It can result in covert discrimination by multiple, small insults and indignities. It is characterized by judgments of another person's perceived mental health status. These judgments are followed by actions such as blatant, overt discrimination which may include refusal of service, or the denial of human rights. Mentalism impacts how individuals are treated by the general public, by mental health professionals, and by institutions, including the legal system. The negative attitudes involved may also be internalized. The terms mentalism, from "mental", and sanism, from "sane", have become established in some contexts, though concepts such as social stigma, and in some cases ableism, may be used in similar but not identical ways. While mentalism and sanism are used interchangeably, sanism is becoming predominant in certain circles, such as academics, those who identify as mad and mad advocates and in a socio-political context where sanism is gaining ground as a movement. The movement of sanism is an act of resistance among those who identify as mad, consumer survivors, and mental health advocates. In academia evidence of this movement can be found in the number of recent publications about sanism and social work practice.
  • 1.9K
  • 10 Nov 2022
Topic Review
Power (Social)
Power, in a social context, refers to the ability of an individual, group, or institution to influence or control the behavior, decisions, and actions of others. It often manifests in various forms, including political, economic, and social power, and is a dynamic force that shapes relationships and structures within societies. The possession of power grants the capacity to enforce one's will, make decisions, and shape the course of events, playing a central role in the dynamics of governance, social interactions, and institutional structures.
  • 1.9K
  • 25 Jan 2024
Topic Review
Alcohol Craving
Craving is a multidimensional phenomenon involving an intense urge to consume substances. It is perceived as an individual experience of “wanting” a drug that may result in motivational and drug-seeking behavioral patterns. Alcohol craving has been extensively studied due to its clinical implications in the development and maintenance of alcohol use disorder (AUD). Craving is considered one of the mechanisms that promote relapse after treatment discharge and even after a prolonged period of abstinence. To better understand the magnitude of the relationship between craving and relapse, it is fundamental to explore factors associated with alcohol craving as it may help in the development of more efficient treatment approaches to prevent relapse in AUD patients.
  • 1.9K
  • 28 Sep 2020
Topic Review
Diarylureas
The diarylurea is a scaffold of great importance in medicinal chemistry as it is present in numerous heterocyclic compounds with antithrombotic, antimalarial, antibacterial, and anti-inflammatory properties.
  • 1.9K
  • 25 Jan 2021
Topic Review
Edible Insect-Based Foods in Europe
All over the world, a large proportion of the population consume insects as part of their diet. In Western countries, however, the consumption of insects is perceived as a negative phenomenon. The consumption of insects worldwide can be considered in two ways: on the one hand, as a source of protein in countries affected by hunger, while, on the other, as an alternative protein in highly-developed regions, in response to the need for implementing policies of sustainable development. This entry focused on both the regulations concerning the production and marketing of insects in Europe and the characteristics of edible insects that are most likely to establish a presence on the European market. The paper indicates numerous advantages of the consumption of insects, not only as a valuable source of protein but also as a raw material rich in valuable fatty acids, vitamins, and mineral salts.
  • 1.9K
  • 21 Apr 2021
Topic Review
Artificial Intelligent in Education
The application of Artificial Intelligence or AI in education has been the subject of academic research. The field examines learning wherever it occurs, in traditional classrooms or at workplaces so to support formal education and lifelong learning. It combines interdisciplinary AI and learning sciences (such as education, psychology, neuroscience, linguistics, sociology and anthropology) in order to facilitate the development of effective adaptive learning environments and various flexible, inclusive tools. Nowadays, there are several new challenges in the field of education technology in the era of smart phones, tablets, cloud computing, Big Data, etc., whose current research questions focus on concepts such as ICT-enabled personalized learning, mobile learning, educational games, collaborative learning on social media, MOOCs, augmented reality application in education and so on. Therefore, to meet these new challenges in education, several fields of research using AI have emerged over time to improve teaching and learning using digital technologies.
  • 1.9K
  • 03 Mar 2022
Topic Review
False Data Injection Attacks
False data injection attacks (FDIAs), as a covert cyber-attack method, pose a huge challenge to the safe and stable operation of smart grids by illegally hacking into power systems to tamper with measurement data and thus undermine data integrity.
  • 1.9K
  • 06 Apr 2022
Topic Review
Foreign Direct Investment and Corruption in Brazil
Foreign Direct Investment (FDI) is seen as a significant driver of economic growth and a potential ally in the struggle against poverty and inequality, making emerging countries focus on attracting this type of investment. Thus, understanding factors that impact the concentration of regional FDI is essential to verifying which characteristics encourage or deter foreign investment.
  • 1.9K
  • 30 May 2022
Topic Review
Matrix Vesicle-Mediated and Osteocytic Regulation of Bone Mineralization
Bone mineralization entails two mineralization phases: primary and secondary mineralization. Primary mineralization is achieved when matrix vesicles are secreted by osteoblasts, and thereafter, bone mineral density gradually increases during secondary mineralization. Nearby extracellular phosphate ions (PO43−) flow into the vesicles via membrane transporters and enzymes located on the vesicles’ membranes, while calcium ions (Ca2+), abundant in the tissue fluid, are also transported into the vesicles. The accumulation of Ca2+ and PO43− in the matrix vesicles induces crystal nucleation and growth. The calcium phosphate crystals grow radially within the vesicle, penetrate the vesicle’s membrane, and continue to grow outside the vesicle, ultimately forming mineralized nodules. The mineralized nodules then attach to collagen fibrils, mineralizing them from the contact sites (i.e., collagen mineralization). Afterward, the bone mineral density gradually increases during the secondary mineralization process.
  • 1.9K
  • 28 Sep 2022
Topic Review
Transparent Wood Composites
Transparent wood composites are novel wood materials which have up to 90% transparency and some higher mechanical properties than wood itself, made for the first time in 1992. When these materials are made commercially available, a significant benefit is expected due to their inherent biodegradable properties; however, this has the axiomatic disadvantage of being problematic for long-term construction. These materials are significantly more biodegradable than glass and plastics. Transparent wood is also shatterproof. On the other hand, concerns may be relevant due to the use of non-biodegradable plastics for long-lasting purposes such as in buildings. File:Example of Transparent Wood and Light diffusion.webm
  • 1.9K
  • 11 Nov 2022
Topic Review
Smart ECM-Based Electrospun Biomaterials
Electrospinning is a well-known technique to produce fibers that mimic the three dimensional microstructural arrangements of the extracellular matrix fibers. Natural and synthetic polymers are used in the electrospinning process; moreover, a blend of them provides composite materials that have demonstrated the potential advantage of supporting cell function and adhesion. Recently, the decellularized extracellular matrix (dECM), which is the noncellular component of tissue that retains relevant biological cues for cells, has been evaluated as a starting biomaterial to realize composite electrospun constructs. The properties of the electrospun systems can be further improved with innovative procedures of functionalization with biomolecules. Among the various approaches, great attention is devoted to the “click” concept in constructing a bioactive system, due to the modularity, orthogonality, and simplicity features of the “click” reactions. Here, we provide an overview of current approaches that can be used to obtain biofunctional composite electrospun biomaterials and propose a design of a smart ECM-based electrospun system suitable for skeletal muscle tissue regeneration.
  • 1.9K
  • 24 Sep 2020
Topic Review
Chitosan Adsorbent
Chitin is mentioned as the second most abundant and important natural biopolymer in worldwide scale. The main sources for the extraction and exploitation of this natural polysaccharide polymer are crabs and shrimps. Chitosan (poly-β-(1 → 4)-2-amino-2-deoxy-d-glucose) is the most important derivative of chitin and can be used in a wide variety of applications including cosmetics, pharmaceutical and biomedical applications, food, etc., giving this substance high value-added applications. Moreover, chitosan has applications in adsorption because it contains amino and hydroxyl groups in its molecules, and can thus contribute to many possible adsorption interactions between chitosan and pollutants (pharmaceuticals/drugs, metals, phenols, pesticides, etc.). However, it must be noted that one of the most important techniques of decontamination is considered to be adsorption because it is simple, low-cost, and fast. 
  • 1.9K
  • 01 Jun 2021
Topic Review
Histamine: A Bacterial Signal Molecule
Histamine is a key signal molecule in humans, with multiple functions, such as being a neurotransmitter or modulator of immune responses. More recent studies have shown that bacteria have evolved different mechanisms to sense histamine or histamine metabolites. Histamine sensing in the human pathogen Pseudomonas aeruginosa was found to trigger chemoattraction to histamine and to regulate the expression of many virulence-related genes.
  • 1.9K
  • 17 Jun 2021
Topic Review
Natural Photosensitizers in Photodynamic Therapy
Photodynamic therapy (PDT) is a therapy for the treatment of many diseases, including cancer. This therapy uses a combination of a photosensitizer (PS), light irradiation of appropriate length and molecular oxygen. The photodynamic effect kills cancer cells through apoptosis, necrosis, or autophagy of tumor cells.
  • 1.9K
  • 29 Mar 2022
Topic Review
Alpha-Amanitin
alpha-Amanitin or α-amanitin is a cyclic peptide of eight amino acids. It is possibly the most deadly of all the amatoxins, toxins found in several species of the mushroom genus Amanita, one being the death cap (Amanita phalloides) as well as the destroying angel, a complex of similar species, principally A. virosa and A. bisporigera. It is also found in the mushrooms Galerina marginata and Conocybe filaris. The oral -1">50 of amanitin is 100 μg/kg for rats. Unlike most cyclic peptides, amatoxins (and phallotoxins) are synthesized on ribosomes. The genes encoding the proprotein for α-amanitin belong to the same family as those that encode for phallacidin (a phallotoxin).
  • 1.9K
  • 14 Oct 2022
Topic Review
Fermentation (Food)
Fermentation typically refers to the conversion of sugar to alcohol using yeast. However, a more appropriate definition would be the chemical conversion of carbohydrates into alcohols or acids. The process is used to produce wine, beer and leavened bread, but fermentation is also employed in preservation to create lactic acid in sour foods such as pickled cucumbers, kimchi and yogurt. The science of fermentation is known as zymology.
  • 1.9K
  • 14 Apr 2023
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