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Topic Review
Employee Creativity
Employee creativity means individuals could work innovatively and proactively in order to create exceptional results. Individuals who can creatively solve problems and work proactively are required by every sector. From an organizational perspective, to cope with an uncertain environment and achieve sustainable growth, employees are expected not only to perform their formal roles, but also to engage themselves in different informal roles, like their creative performance. The current surge in the organizational literature is evident of the fact that the importance of creative employees is being recognized by various contemporary scholars.
  • 3.4K
  • 13 Sep 2021
Topic Review
Diversity and Role of Latex in Plant Physiology
Latex, a sticky emulsion produced by specialized cells called laticifers, is a crucial part of a plant’s defense system against herbivory and pathogens. It consists of a broad spectrum of active compounds, which are beneficial not only for plants, but for human health as well, enough to mention the use of morphine or codeine from poppy latex.
  • 3.4K
  • 30 Nov 2021
Topic Review
Tropospheric Ozone
Ozone (O3) is a trace gas of the troposphere, with an average concentration of 20–30 parts per billion by volume (ppbv), with close to 100 ppbv in polluted areas. Ozone is also an important constituent of the stratosphere, where the ozone layer exists which is located between 10 and 50 kilometers above the earths surface. The troposphere is the lowest layer of the Earth's atmosphere. It extends from the ground up to a variable height of approximately 14 kilometers above sea level. Ozone is least concentrated in the ground layer (or planetary boundary layer) of the troposphere. Ground level or tropospheric ozone is created by chemical reactions between oxides of nitrogen (NOx gases) and volatile organic compounds (VOCs). The combination of these chemicals in the presence of sunlight form ozone. Its concentration increases as height above sea level increases, with a maximum concentration at the tropopause. About 90% of total ozone in the atmosphere is in the stratosphere, and 10% is in the troposphere. Although tropospheric ozone is less concentrated than stratospheric ozone, it is of concern because of its health effects. Ozone in the troposphere is considered a greenhouse gas, and may contribute to global warming. Photochemical and chemical reactions involving ozone drive many of the chemical processes that occur in the troposphere by day and by night. At abnormally high concentrations (the largest source being emissions from combustion of fossil fuels), it is a pollutant, and a constituent of smog. Its levels have increased significantly since the industrial revolution, as NOx gasses & VOCs are some of the byproducts of combustion. With more heat and sunlight in the summer months, more ozone is formed which is why regions often experience higher levels of pollution in the summer months. Although the same molecule, ground level ozone can be harmful to our health, unlike stratospheric ozone that protects the earth from excess UV radiation. Photolysis of ozone occurs at wavelengths below approximately 310–320 nanometres. This reaction initiates the chain of chemical reactions that remove carbon monoxide, methane, and other hydrocarbons from the atmosphere via oxidation. Therefore, the concentration of tropospheric ozone affects how long these compounds remain in the air. If the oxidation of carbon monoxide or methane occur in the presence of nitrogen monoxide (NO), this chain of reactions has a net product of ozone added to the system.
  • 3.4K
  • 24 Nov 2022
Biography
P. M. H. Atwater
P. M. H. Atwater (born Phyllis Marie DeKeyser, September 19, 1937) is a North American writer and researcher on subjects related to Idaho, life and death issues, and spirituality from a New Thought point of view. Atwater was born in Twin Falls, Idaho[1] and was later adopted by Kenneth L. Johnston. She married John Bernard Huffman in 1956 (divorced in 1976) and had three children: Kelly, Nata
  • 3.4K
  • 12 Dec 2022
Topic Review
The World Health Organization (WHO): An In-Depth Overview
The World Health Organization (WHO), established in 1948, is a specialized agency of the United Nations focused on international public health. Headquartered in Geneva, Switzerland, WHO plays a pivotal role in global health governance by providing leadership on health matters, setting norms and standards, and offering technical support to countries. The organization is structured into six regional offices and is governed by the World Health Assembly and the Executive Board. WHO’s core areas of focus include combating infectious diseases, addressing non-communicable diseases, strengthening health systems, and responding to health emergencies. Notably, WHO led the global eradication of smallpox and has been instrumental in initiatives against polio, HIV/AIDS, and most recently, COVID-19. Despite its successes, WHO faces challenges such as funding constraints, bureaucratic inefficiencies, and political pressures. As it looks to the future, WHO’s work will continue to be guided by its commitment to promoting health, achieving universal health coverage, and addressing emerging health threats, ensuring its ongoing relevance and impact in global health.
  • 3.4K
  • 04 Sep 2024
Topic Review
PET-RAFT
Photoinduced Electron/Energy Transfer Reversible Addition-Fragmentation Chain-Transfer (PET-RAFT) polymerization, proposed for the first time in 2014, is based on an alternative activation of the thiocarbonylthio compounds through photoredox catalysts (PCs). This last presents significant advantages compared to other photochemical techniques in terms of applicability, cost, and sustainability. 
  • 3.4K
  • 26 May 2021
Topic Review
Immune Engineering Approaches to Improve Wound Healing
Recently, targeted modulation of the immune response via biotechnological approaches and biomaterials has gained attention as a means to restore the pro-healing phenotype and promote tissue regeneration. In order to fully realize the potential of these approaches in traumatic wounds, a critical and nuanced understanding of the relationships between immune dysregulation and healing outcomes is needed. 
  • 3.4K
  • 27 Apr 2022
Topic Review
Cultural Divide
A cultural divide is "a boundary in society that separates communities whose social economic structures, opportunities for success, conventions, styles, are so different that they have substantially different psychologies". A cultural divide is the virtual barrier caused by cultural differences, that hinder interactions, and harmonious exchange between people of different cultures. For example, avoiding eye contact with a superior shows deference and respect in East Asian cultures, but can be interpreted as suspicious behavior in Western cultures. Studies on cultural divide usually focus on identifying and bridging the cultural divide at different levels of society.
  • 3.4K
  • 13 Oct 2022
Topic Review Peer Reviewed
COVID-19 and Dentistry
Dentistry is a healthcare profession requiring close contacts between the dental practitioner and the patient. In particular, many dental procedures generate aerosols and droplets which are proved to be the major transmission route for COVID-19.
  • 3.4K
  • 13 Apr 2022
Topic Review
Nuclear Pore Complex
The import and export of proteins requires interaction with the components of the nuclear envelope (NE), which is formed by a double membrane that harbor protein channels called nuclear pore complexes (NPCs). NPCs are formed by multiple copies of Nups that participate in the bi-directional nucleus–cytoplasmic transport of macromolecules, ribosomal subunits, viral proteins and RNAs (mRNAs, rRNAs, tRNAs, miRNAs) from both cellular and viral origin.
  • 3.4K
  • 28 Apr 2021
Topic Review
Graph Modeling of Shop Schedulings
Graphs are powerful tools to model manufacturing systems and scheduling problems. The complexity of these systems and their scheduling problems has been substantially increased by the ongoing technological development. Thus, it is essential to generate sustainable graph-based modeling approaches to deal with these excessive complexities. Graphs employ nodes and edges to represent the relationships between jobs, machines, operations, etc. Despite the significant volume of publications applying graphs to shop scheduling problems, the literature lacks a comprehensive survey study. We proposed the first comprehensive review paper which 1) systematically studies the overview and the perspective of this field, 2) highlights the gaps and potential hotspots of the literature, and 3) suggests future research directions towards sustainable graphs modeling the new intelligent/complex systems. We carefully examined 143 peer-reviewed journal papers published from 2015 to 2020. About 70% of our dataset were published in top-ranked journals which confirms the validity of our data and can imply the importance of this field. After discussing our generic data collection methodology, we proposed categorizations over the properties of the scheduling problems and their solutions. Then, we discussed our novel categorization over the variety of graphs modeling scheduling problems. Finally, as the most important contribution, we generated a creative graph-based model from scratch to represent the gaps and hotspots of the literature accompanied with statistical analysis on our dataset. Our analysis showed a significant attention towards job shop systems (56%) and Un/Directed Graphs (52%) where edges can be either directed, or undirected, or both. Whereas 14% of our dataset applied only Undirected Graphs, and 11% targeted hybrid systems, e.g., mixed shop, flexible and cellular manufacturing systems which shows potential future research directions.
  • 3.4K
  • 25 May 2021
Topic Review
The Bioactivity and Health Benefits of Alpha-Phellandrene
Aromatic essential oils play a significant role in pharmaceuticals, food additives, cosmetics, and perfumery. Essential oils mostly comprise aliphatic hydrocarbons, monoterpenoids, sesquiterpenoids and diterpenes. Plant extracts comprise a complex mixture of terpenes, terpenoids, aliphatic and phenol-derived aromatic components. Terpenes are a significant class of hydrocarbons with numerous health benefits. Monoterpenes are the most important constituents of essential oils. α-phellandrene (α-PHE) is a cyclic monoterpene with two double bonds in a heterocyclic ring (endocyclic).
  • 3.4K
  • 20 Oct 2022
Topic Review
CNO Cycle
The CNO cycle (for carbon–nitrogen–oxygen; sometimes called Bethe–Weizsäcker cycle after Hans Albrecht Bethe and Carl Friedrich von Weizsäcker) is one of the two known sets of fusion reactions by which stars convert hydrogen to helium, the other being the proton–proton chain reaction (p-p cycle), which is more efficient at the Sun's core temperature. The CNO cycle is hypothesized to be dominant in stars that are more than 1.3 times as massive as the Sun. Unlike the proton-proton reaction, which consumes all its constituents, the CNO cycle is a catalytic cycle. In the CNO cycle, four protons fuse, using carbon, nitrogen, and oxygen isotopes as catalysts, each of which is consumed at one step of the CNO cycle, but re-generated in a later step. The end product is one alpha particle (a stable helium nucleus), two positrons, and two electron neutrinos. There are various alternative paths and catalysts involved in the CNO cycles, all these cycles have the same net result: The positrons will almost instantly annihilate with electrons, releasing energy in the form of gamma rays. The neutrinos escape from the star carrying away some energy. One nucleus goes on to become carbon, nitrogen, and oxygen isotopes through a number of transformations in an endless loop. The proton–proton chain is more prominent in stars the mass of the Sun or less. This difference stems from temperature dependency differences between the two reactions; pp-chain reaction starts at temperatures around 4×106 K (4 megakelvin), making it the dominant energy source in smaller stars. A self-maintaining CNO chain starts at approximately 15×106 K, but its energy output rises much more rapidly with increasing temperatures so that it becomes the dominant source of energy at approximately 17×106 K. The Sun has a core temperature of around 15.7×106 K, and only 1.7% of 4He nuclei produced in the Sun are born in the CNO cycle. The CNO-I process was independently proposed by Carl von Weizsäcker and Hans Bethe in the late 1930s. The first reports of the experimental detection of the neutrinos produced by the CNO cycle in the Sun were published in 2020. This was also the first experimental confirmation that the Sun had a CNO cycle, that the proposed magnitude of the cycle was accurate, and that von Weizsäcker and Bethe were correct.
  • 3.4K
  • 03 Nov 2022
Topic Review
Fluid and Crystallized Intelligence
The concepts of fluid intelligence (gf) and crystallized intelligence (gc) were introduced in 1963 by the psychologist Raymond Cattell. According to Cattell's psychometrically-based theory, general intelligence (g) is subdivided into gf and gc. Fluid intelligence is the ability to solve novel reasoning problems and is correlated with a number of important skills such as comprehension, problem solving, and learning. Crystallized intelligence, on the other hand, involves the ability to deduce secondary relational abstractions by applying previously learned primary relational abstractions.
  • 3.4K
  • 18 Nov 2022
Topic Review
Working Fluids
Heat engines, refrigeration cycles and heat pumps usually involve a fluid to and from which heat is transferred while undergoing a thermodynamic cycle. This fluid is called the working fluid. Refrigeration and heat pump technologies often refer to working fluids as refrigerants. Most thermodynamic cycles make use of the latent heat (adventages of phase change) of the working fluid. In case of other cycles the working fluid remains in gaseous phase while undergoing all the processes of the cycle. When it comes to heat engines, working fluid generally undergoes a combustion process as well, for example in internal combustion engines or gas turbines. There are also technologies in heat pump and refrigeration, where working fluid does not change phase, such as reverse Brayton or Stirling cycle. This article summarises the main critera of selecting working fluids for a thermodynamic cycle, such as heat engines including low grade heat recovery using Organic Rankine Cycle (ORC) for geothermal energy, waste heat, thermal solar energy or biomass and heat pumps and refrigeration cycles. The article addresses how working fluids affect technological applications, where the working fluid undergoes a phase transition and does not remain in its original (mainly gaseous) phase during all the processes of the thermodynamic cycle. Finding the optimal working fluid for a given purpose – which is essential to achieve higher energy efficiency in the energy conversion systems – has great impact on the technology, namely it does not just influence operational variables of the cycle but also alters the layout and modifies the design of the equipment. Selection criteria of working fluids generally include thermodynamic and physical properties besides economical and environmental factors, but most often all of these criteria are used together.
  • 3.4K
  • 04 Nov 2022
Topic Review
Tonsillolith
Tonsilloliths, also known as tonsil stones, are soft aggregates of bacterial and cellular debris that form in the tonsillar crypts, the crevices of the tonsils. While they occur most commonly in the palatine tonsils, they may also occur in the lingual tonsils. Tonsil stones are common. Tonsilloliths have been recorded weighing from 0.3 g to 42 g. Protruding tonsilloliths may feel like foreign objects lodged in the tonsil crypt. They may be a nuisance and difficult to remove, but are usually not harmful. They are one of the causes of bad breath and always give off a putrid smell.
  • 3.4K
  • 11 Nov 2022
Topic Review
Coracle
A coracle is a small, rounded, lightweight boat of the sort traditionally used in Wales, and also in parts of the West Country and in Ireland, particularly the River Boyne, and in Scotland, particularly the River Spey. The word is also used of similar boats found in India , Vietnam, Iraq and Tibet. The word "coracle" is an English spelling of the original Welsh cwrwgl, cognate with Irish and Scottish Gaelic currach, and is recorded in English text as early as the sixteenth century. Other historical English spellings include corougle, corracle, curricle and coricle.
  • 3.4K
  • 05 Nov 2022
Topic Review
Types of Faults on Switchgear
Switchgear is generally known as a switching device. It is used for circuit isolation and the protection of power systems from overload and system faults. The definition of switchgear also includes devices that are utilized to regulate, meter, and control power systems. The term refers to switching and interrupting devices, as well as their combinations with control, instrumentation, metering, protective, and regulating devices, as well as the components of devices involved in dealing with interconnections, items, and supporting structures, which are used primarily in the generation, transmitting distribution, and conversion of electrical power.
  • 3.4K
  • 23 Sep 2022
Topic Review Peer Reviewed
Listericidal Novel Processing Technological Approaches for the Safety of Milk and Dairy Products: A Systematic Review
Listeria monocytogenes is a major public health concern in milk and ready-to-eat dairy products. To meet consumer demand for fresher, minimally processed foods with high nutritional and sensory quality, several non-thermal technologies are being explored as alternatives to conventional heat treatments. This systematic review (2020–2025), following PRISMA guidelines, examines recent applications of selected non-thermal technologies to control Listeria in milk and dairy matrices. Peer-reviewed studies available in full-text, in English or Spanish, focusing on applications at laboratory or pilot plant scales, with milk or dairy produced onsite or purchased, containing Listeria sp., were included. Studies with applications to plant-based or non-dairy products or those not inoculated with Listeria, were excluded. Conference abstracts, corrections, editorials, letters, news, and scientific opinions were excluded as well. The databases searched were Web of Science, Scopus, and ProQuest, which were last consulted in April 2025. Given the naturality of the review, the risk of bias was assessed through independent screening by two of the researchers, focusing on clear objectives, analytical validity, statistical analysis, and methodology. The results are presented in tabulated format. Of the 157 records identified, 22 were included in this review. Seven of the records reported hurdle technologies, while fifteen reported single technology applications, with high-pressure processing being the most frequent. Limitations observed are primarily the use of unreported strains, a lack of information regarding the initial load of inoculum, and expected log reductions. The equipment used is mostly at the laboratory scale, except for HPP. Non-thermal technologies present a promising option for the control of Listeria in dairy products. The basic principles of GMP, HACCP, and cold-chain control in dairy processing are of special importance in safety assurance. This research was funded by Vicerrectoría de Investigación, Universidad de Costa Rica, grant number 735-C3-460.
  • 3.4K
  • 10 Sep 2025
Topic Review
Home Theater PC
A home theater PC (HTPC) or media center computer is a convergent device that combines some or all the capabilities of a personal computer with a software application that supports video, photo, audio playback, and sometimes video recording functionality. In recent years, other types of consumer electronics, including game consoles and dedicated media devices, have crossed over to manage video and music content. The term "media center" also refers to specialized application software designed to run on standard personal computers. HTPC and other convergent devices integrate components of a home theater into a unit co-located with a home entertainment system. An HTPC system typically has a remote control and the software interface normally has a 10-foot (3 m) user interface design so that it can be comfortably viewed at typical television viewing distances. An HTPC can be purchased pre-configured with the required hardware and software needed to add video programming or music to the PC. Enthusiasts can also piece together a system out of discrete components as part of a software-based HTPC. Since 2007, digital media player and smart TV software has been incorporated into consumer electronics through software or hardware changes including video game consoles, Blu-ray players, networked media players, televisions, and set-top boxes. The increased availability of specialized devices, coupled with paid and free digital online content, now offers an alternative to multipurpose (and more costly) personal computers.
  • 3.4K
  • 08 Nov 2022
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