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Topic Review
Cationic Surfactants
Cationic surfactants are a class of surfactant molecules that contain a positively charged head group and a long hydrophobic tail. They have a wide range of properties that make them useful in various applications, including solubility in water and organic solvents, high surface activity, emulsification, antimicrobial activity, conditioning properties, and fabric softening. However, some cationic surfactants can be toxic to aquatic life, so they should be used with caution in applications where they may come into contact with the environment. Overall, cationic surfactants are important molecules that play a crucial role in various industrial, personal care, and household applications. Cationic surfactants are a type of surfactant that have a positively charged hydrophilic (water-loving) head and a hydrophobic (water-hating) tail. The positive charge on the head of the surfactant makes it attracted to negatively charged surfaces, such as cell membranes and proteins. Due to their positive charge, cationic surfactants are often used in personal care and household cleaning products, as well as in the textile and paper industries. They are effective in removing dirt, oil, and other contaminants from surfaces, as they can bind to these substances and help to lift them away from the surface. Cationic surfactants can also have antimicrobial properties, as they can disrupt the cell membranes of bacteria and other microorganisms. This makes them useful in disinfectants, as well as in personal care products such as shampoos and body washes.
  • 3.8K
  • 24 Mar 2023
Topic Review
False Position Method
In mathematics, the false position method or regula falsi is a very old method for solving an equation in one unknown, that, in modified form, is still in use. In simple terms, the method is the trial and error technique of using test ("false") values for the variable and then adjusting the test value according to the outcome. This is sometimes also referred to as "guess and check". Versions of the method predate the advent of algebra and the use of equations. As an example, consider problem 26 in the Rhind papyrus, which asks for a solution of (written in modern notation) the equation x + x/4 = 15. This is solved by false position, using a technique that predates formally written equations. First, guess that x = 4 to obtain, on the left, 4 + 4/4 = 5. This guess is a good choice since it produces an integer value. However, 4 is not the solution of the original equation, as it gives a value which is three times too small. To compensate, multiply x (currently set to 4) by 3 and substitute again to get 12 + 12/4 = 15, verifying that the solution is x = 12. Modern versions of the technique employ systematic ways of choosing new test values and are concerned with the questions of whether or not an approximation to a solution can be obtained, and if it can, how fast can the approximation be found.
  • 3.8K
  • 15 Nov 2022
Topic Review
Areca nut
Scientific name:  Areca catechu L. Family: Arecaceae Centre of origin: South-East Asia Common name: kamuhu, adakka, adike, Pinang palm, Betel palm, Areca palm, Supari, Kaunga The generic name is derived from the common name used by the people of the Malabar Coast in southwestern India.
  • 3.8K
  • 16 Feb 2022
Topic Review
An Analysis of the Board of Directors Composition
Abstract:   Purpose: The objectives of this study were to analyse certain aspects of the Board composition of Maltese listed companies (MLCs), namely Board size, independence, expertise, gender diversity and the chairperson/CEO links, and  how these may be improved. Design/Approach/Methodology: The study was designed around a qualitative approach of data collection. Semi-structured interviews were conducted with seventeen participants, consisting of fourteen company secretaries of MLCs, a representative of the Maltese regulator, a corporate advisor and a corporate lawyer. Findings: The nomination and appointment process of directors in MLCs relies mainly on networking, with a tendency to continuously appoint the same tried network of directors. This creates a barrier towards new talent being introduced into boardrooms. A general disagreement also persists as to what constitutes a truly independent Board member. Practical Implications: Practical experience often supplants academic qualifications when nominating and appointing directors. Moreover, female representation on the Boards of MLCs is still lacking. Notwithstanding the fact that the importance of having separate chairperson/CEO roles is acknowledged, there is likely to be strong resistance to any law rendering this mandatory.   Originality/Value: Studies relating to the composition of the Board of Directors in smaller states such as the island state of Malta are infrequent. This paper provides information that is of particular value to listed companies in smaller states and their stakeholders, including regulators and sheds more light on the priniciple of proportionailty when dealing with requirements imposed by the authorities.
  • 3.8K
  • 13 Apr 2021
Topic Review
Diagnosis and Management of Onychotillomania
Onychotillomania is defined as repetitive picking or pulling of the nail unit, causing damage to the nail matrix, nail bed, nail plate and/or periungual skin.
  • 3.8K
  • 23 Mar 2022
Topic Review
Continuationism
Continuationism is a Christian theological belief that the gifts of the Holy Spirit have continued to the present age, specifically those sometimes called "sign gifts", such as tongues and prophecy. Continuationism is the opposite of cessationism. Continuationists believe that the miraculous gifts of the Holy Spirit are still distributed today, are still in use, and are still needed in the church. The same Holy Spirit that the Apostle Paul wrote of, claiming that it gave him supernatural abilities, was also written about in the Old Testament, which claims that it also endowed such abilities upon those whom God chose to accomplish his works, as in the New Testament. Historically, the Lutheran, Methodist, Moravian, and Pentecostal traditions of Christianity have espoused the doctrinal position of continuationism.
  • 3.8K
  • 11 Oct 2022
Topic Review
Rolls-Royce Phantom VII
The Rolls-Royce Phantom VII is a full-sized luxury saloon car made by Rolls-Royce Motor Cars. Launched in 2003, it was the first Rolls-Royce developed and introduced after BMW purchased the right to use the Rolls-Royce name and logo in 1998. It is credited with successfully reviving the Rolls-Royce brand and restoring Rolls-Royce's reputation as a maker of luxury cars. The Phantom Drophead Coupé and Phantom Coupé are two-door derivatives of the Phantom launched in 2007 and 2008, respectively. From 2003 until the launch of the smaller Ghost in 2009, the Phantom was the only car produced by Rolls-Royce. The Phantom acted as the company's flagship model, but was less exclusive than all previous Phantoms (none of which surpassed the 600 per year).
  • 3.8K
  • 05 Dec 2022
Topic Review
Internet of Things in the Industry Revolution 4.0
Researchers offers a wide range of information on Industry 4.0, finds research gaps and recommends future directions. Seven research questions are addressed: (i) What are the contributions of WSN in IR 4.0? (ii) What are the contributions of IoT in IR 4.0? (iii) What are the types of WSN coverage areas for IR 4.0? (iv) What are the major types of network intruders in WSN and IoT systems? (v) What are the prominent network security attacks in WSN and IoT? (vi) What are the significant issues in IoT and WSN frameworks? and (vii) What are the limitations and research gaps in the existing work? Researchers mainly focuses on the solutions and new techniques to automate Industry 4.0 and analyzed over 130 articles from 2014 until 2021. The entry covers several aspects of Industry 4.0, from the designing phase to security needs, from the deployment stage to the classification of the network, the difficulties, challenges, and future directions.
  • 3.8K
  • 16 Mar 2022
Topic Review
Forgetting
Forgetting or disremembering is the apparent loss or modification of information already encoded and stored in an individual's short or long-term memory. It is a spontaneous or gradual process in which old memories are unable to be recalled from memory storage. Problems with remembering, learning and retaining new information are a few of the most common complaints of older adults. Studies show that retention improves with increased rehearsal. This improvement occurs because rehearsal helps to transfer information into long-term memory. Forgetting curves (amount remembered as a function of time since an event was first experienced) have been extensively analyzed. The most recent evidence suggests that a power function provides the closest mathematical fit to the forgetting function.
  • 3.8K
  • 09 Oct 2022
Topic Review
Water-Related Issues in Bhutan
Water for hydropower in Bhutan has been in focus as compared to that allocated for irrigation, industries, and environmental demand. The demand for water in Bhutan has also increased in the last decade due to population increase, changes in lifestyle, and economic advancements through tourism and hydropower projects.
  • 3.8K
  • 28 Apr 2021
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