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Topic Review
Reaction
As described by the third of Newton's laws of motion of classical mechanics, all forces occur in pairs such that if one object exerts a force on another object, then the second object exerts an equal and opposite reaction force on the first. The third law is also more generally stated as: "To every action there is always opposed an equal reaction: or the mutual actions of two bodies upon each other are always equal, and directed to contrary parts." The attribution of which of the two forces is the action and which is the reaction is arbitrary. Either of the two can be considered the action, while the other is its associated reaction.
  • 2.4K
  • 30 Oct 2022
Topic Review
Techniques of Image Encryption For Medical Applications
In medical information systems, image data can be considered crucial information. As imaging technology and methods for analyzing medical images advance, there will be a greater wealth of data available for study. Hence, protecting those images is essential. Image encryption methods are crucial in multimedia applications for ensuring the security and authenticity of digital images. 
  • 2.4K
  • 29 Aug 2023
Topic Review
Plasmonic biosensing schemes for virus
The uncertain proportions of pandemic outbreaks have triggered the need of reliable and cost-effective protocols easily adaptable to the changing virulence of virus strains. In recent years, plasmonic biosensors are being increasingly applied for clinical diagnosis of viral and other infectious diseases. Typical plasmonic biosensing strategies rely on the versatility of SPR and LSPR as label-free detection systems capable of monitoring binding interactions in a short period of time. Nevertheless, the incorporation of technological advancements has precipitated the development of nanomaterial-based applications for improving the sensitivity and specificity of classical configurations. The unique optical properties of plasmonic nanostructures has been exploited in combination with SERS colorimetric, fluorescence or luminescence enhancement for viral diagnosis. Likewise, the development of plasmonic virus sensing approaches has also benefitted from the variety of virus biomarkers. Thus, a high number of virus plasmonic biosensors have prompted the advance of novel functionalization strategies to achieve the effective coverage of the biological receptor while ensuring the affinity and specificity towards the target viral nucleic acids, proteins or whole virus. The huge potential for single virus detection along with the effectiveness and simplicity of current plasmonic configurations will impact on the routine surveillance of virus in clinical settings during this decade.
  • 2.4K
  • 27 Oct 2020
Topic Review
Reaction Mechanism of Olefins
Light olefins (C2-C4) are important C-building blocks which are currently used to produce a variety of chemicals, such as elastomers, medicines, cosmetics, detergents, solvents, etc. They can be produced by steam cracking, fluid catalytic cracking of naphtha, direct/indirect conversion of synthesis gas (CO + H2) or by hydrogenation of CO2 using H2 from renovable energy sources. However, the catalytic production of light olefins from CO2 is difficult due to the chemical inactivity of CO2 molecule, the high C-C coupling barrier and the necesity to limit the formation of C-C bond and methane. Therefore, the catalysts required for this reaction must to be multifunctional and have an optimized amount of active sites. 
  • 2.4K
  • 29 Nov 2021
Topic Review
Durability of Foam Concrete
Foam concrete is a type of concrete that is produced by locking air voids in the mortar with the help of a suitable foaming agent and is classified as lightweight concrete. It has low self-weight, minimum aggregate consumption (no coarse aggregate is used), high fluidity, controlled low strength and thermal insulation. The properties of foam concrete are affected by the production method and the materials used. Unlike other porous lightweight concrete, prefabricated foams with foaming agents are added to fresh cement paste and mortar. The air pores brought by the foams constitute 10–90% by volume of the hardened body. This porous structure forms the basis of the mechanical properties, thermal conductivity, acoustic and durability properties of foam concrete. One of the advantages of foam concrete is its weight reduction (up to 80%) compared to conventional concrete. The air bubbles are evenly distributed in the foam concrete body. The pore structure may be affected during the mixing, transportation and placement of fresh concrete, so it should have fixed walls. Air bubbles range in size from approximately 0.1 to 1 mm. The density of foam concrete is mainly affected by the amount of foam and varies between 400 and 1600 kg/m3. It can be used for structural, partitioning, insulation and filling applications with excellent acoustic/thermal insulation, high fire resistance, lower raw material costs, easier pumping and finally no compaction, vibration or leveling.
  • 2.4K
  • 17 Jun 2022
Topic Review
Religion
This is a list of encyclopedias as well as encyclopedic and biographical dictionaries published on the subjects of religion and mythology in any language.
  • 2.4K
  • 13 Oct 2022
Topic Review
Anatomical Variations of the External Jugular Vein
The external jugular vein (EJV) descends superficially to the sternocleidomastoid muscle and drains into the subclavian vein after penetrating the deep cervical fascia. Numerous morphological possibilities of the EJV could occur and should be carefully interpreted. These include fenestrations and double fenestrations, true or false duplications, triplication, absence, aberrant origin or course, bifurcation, or the internal jugular vein termination of the EJV. 
  • 2.4K
  • 31 Mar 2023
Topic Review
Satellite Navigation Signal Authentication Principles and Technical Architecture
As the Global Navigation Satellite System (GNSS) is widely used in all walks of life, the signal structure of satellite navigation is open, and the vulnerability to spoofing attacks is also becoming increasingly prominent, which will seriously affect the credibility of navigation, positioning, and timing (PNT) services. Satellite navigation signal authentication technology is an emerging technical means of improving civil signal anti-spoofing on the satellite navigation system side, and it is also an important development direction and research focus of the GNSS. 
  • 2.4K
  • 12 Apr 2023
Topic Review
Atmospheric Influence on Grapevine Development
In many European regions, viticulture and winemaking play a major socioeconomic role in local economies, with climate being a central component of the terroirs, governing vineyard microclimate, vine development and growth, phenology, yield, and grape berry composition, which ultimately control attributes and typicity of the produced wines. Nonetheless, climate change is already affecting the viticultural suitability of many wine regions throughout the continent and is expected to continue along this same path in the upcoming decades. These climate-driven shifts may lead to a redesign of the geographical distribution of wine regions, while wine typicity may also be threatened in most cases. Climate change does require the implementation of well-timed, appropriate, and economically efficient adaptation strategies, while respecting local specificities for an effective reduction of the risks to which this vulnerable sector is exposed. However, knowledge on the adaptation potential of a range of measures is still incipient and will need more research in the near future.
  • 2.4K
  • 28 Oct 2020
Topic Review
Subcritical-Water Extraction of Natural Products
Subcritical water refers to high-temperature and high-pressure water, but below water's critical point of 374 °C and 218 atm. A unique and useful characteristic of subcritical water is that its polarity can be dramatically decreased with increasing temperature. Therefore, subcritical water can behave similarly to methanol or ethanol. This makes subcritical water a green extraction fluid used for a variety of organic species. 
  • 2.4K
  • 09 Jul 2021
Topic Review
ALBI Grades
Hepatocellular carcinoma (HCC) is a leading cause of death worldwide. Selection of therapeutic modalities and the prognosis of affected patients are well known to be dependent not only on tumor burden, but also hepatic reserve function. Anti-viral treatments for chronic hepatitis related to a viral infection and an increase in cases of non-viral HCC associated with the aging of society have resulted in dramatic changes regarding the characteristics of HCC patients. With recent developments in therapeutic modalities for HCC, more detailed assessment of hepatic function has become an important need. Studies in which the relationship of albumin-bilirubin (ALBI) with prognosis of HCC patients was investigated were reviewed in order to evaluate the usefulness of newly developed ALBI and modified ALBI (mALBI) grades for HCC treatment, as those scoring methods are considered helpful for predicting prognosis and selecting therapeutic modalities based on expected prognosis.
  • 2.4K
  • 27 Oct 2020
Topic Review
Microneedles for Cancer Treatment
Microneedles (MNs) are tiny needle like structures used in drug delivery through layers of the skin. They are non-invasive and are associated with significantly less or no pain at the site of administration to the skin. MNs are excellent in delivering both small and large molecules to the subjects in need thereof. There exist several strategies for drug delivery using MNs, wherein each strategy has its pros and cons. Research in this domain lead to product development and commercialization for clinical use. Additionally, several MN-based products are undergoing clinical trials to evaluate its safety, efficacy, and tolerability. 
  • 2.4K
  • 10 Jan 2021
Topic Review
Chenopodium quinoa (Willd.) Diseases
The journey of the Andean crop quinoa (Chenopodium quinoa Willd.) to unfamiliar environments and the combination of higher temperatures, sudden changes in weather, intense precipitation, and reduced water in the soil has increased the risk of observing new and emerging diseases associated with this crop. Several diseases of quinoa have been reported in the last decade. These include Ascochyta caulina, Cercospora cf. chenopodii, Colletotrichum nigrum, C. truncatum, and Pseudomonas syringae. The taxonomy of other diseases remains unclear or is characterized primarily at the genus level. Symptoms, microscopy, and pathogenicity, supported by molecular tools, constitute accurate plant disease diagnostics in the 21st century. This review aims to compile the existing information and make accurate associations between specific symptoms and causal agents of disease. In addition, we place an emphasis on downy mildew and its phenotyping, as it continues to be the most economically important and studied disease affecting quinoa worldwide. 
  • 2.4K
  • 29 Jun 2021
Topic Review
Nipah Virus
Nipah virus (NiV) is a highly lethal zoonotic paramyxovirus that emerged in Malaysia in 1998. It is a human pathogen capable of causing severe respiratory infection and encephalitis. The natural reservoir of NiV, Pteropus fruit bats, remains a continuous virus source for future outbreaks, although infection in the bats is largely asymptomatic. NiV provokes serious disease in various mammalian species.
  • 2.4K
  • 28 Jun 2022
Topic Review
Melanin Transfer Models
Skin pigmentation ensures efficient photoprotection and relies on the pigment melanin, which is produced by epidermal melanocytes and transferred to surrounding keratinocytes. While the molecular mechanisms of melanin synthesis and transport in melanocytes are now well characterized, much less is known about melanin transfer and processing within keratinocytes.
  • 2.4K
  • 02 Aug 2023
Topic Review
Mechanism of Hydroponic Plants to Purify Wastewater
As the global population reaches eight billion, large quantities of wastewater (domestic, industrial, livestock) need to be treated in an efficient, green, and environmentally friendly manner. Wastewater hydroponics technology (HP) can efficiently remove various pollutants (conventional and emerging pollutants, heavy metals, and microorganisms) and create economic benefits. The principle of hydroponic wastewater purification is phytoremediation, which is a low-cost and solar-powered natural cleaning technology. Plants assist in the removal of pollutants in a variety of ways, including phytoextraction, phytovolatilization, phytodegradation, and rhizofiltration.
  • 2.4K
  • 04 Aug 2023
Topic Review
Silica’s Impact on Concrete Properties in Civil Engineering
Microsilica, a by-product of silicon or ferrosilicon production. Widely utilized within the construction industry, microsilica serves as a modifying component in concrete production, leveraging its chemical composition and physical attributes as a highly active pozzolan. Natural additives encompass crushed volcanic and sedimentary rocks, diatomites, volcanic ash, and tuff. Within technogenic additives lie waste or by-products from various industries, such as fly ash, granulated blast furnace slag, and microsilica.
  • 2.4K
  • 11 Dec 2023
Topic Review
Heterogeneous Catalysts in the Reductive Amination of Alcohols
The synthesis of primary amines via the reductive amination of alcohols involves a hydrogen-borrowing or hydrogen-transfer mechanism, which consists of three main steps: alcohol hydroxyl dehydrogenation, carbonyl imidization, and imine hydrogenation. Heterogeneous catalysts are widely used for this reaction because of their high performance and amenability to separation and reuse.
  • 2.4K
  • 18 Oct 2023
Topic Review
Risk Communication
Risk communication is critical to emergency management. Following the message-centered approach or risk communication, the whole communication process for public health emergency is suggested to integrate the accessibility and openness of risk information, the timing and frequency of communication, and the strategies dealing with uncertainties. Based on these principles a simplified Government–Expert–Public risk communication model can illustrate a collaborative network for effective risk communication.
  • 2.4K
  • 30 Oct 2020
Topic Review
Fusarium oxysporum
Fon has four recognized races: 0, 1, 2, and 3. Each subsequent race is determined by its ability to cause infection on previously resistant cultivars, with race 3 having the largest range of pathogenicity. Although the specific avirulence gene responsible for overcoming cultivar resistance is not known in most races, the ability to cause infection should be characterized as virulence rather than pathogenicity as their differentiation rests on a 1–9 scale of disease rating.
  • 2.4K
  • 24 Sep 2021
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