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Topic Review
Tea EGCG and Coffee CGA
Tea and coffee are consumed worldwide and epidemiological and clinical studies have shown their health beneficial effects, including anti-cancer effects. Epigallocatechin gallate (EGCG) and chlorogenic acid (CGA) are the major components of green tea polyphenols and coffee polyphenols, respectively, and believed to be responsible for most of these effects. Although a large number of cell-based and animal experiments have provided convincing evidence to support the anti-cancer effects of green tea, coffee, EGCG, and CGA, human studies are still controversial and some studies have suggested even an increased risk for certain types of cancers such as esophageal and gynecological cancers with green tea consumption and bladder and lung cancers with coffee consumption. 
  • 4.4K
  • 20 Oct 2020
Topic Review
Papaverine and Its Mechanism of Action
Papaverine has been proven to be a high-value opioid alkaloid in the field of therapeutics either in solitude or in combination with other metabolites/molecules. Pharmacological research has revealed that papaverine demonstrates a variety of biological activities, including activity against erectile dysfunction, postoperative vasospasms, and pulmonary vasoconstriction, as well as antiviral, cardioprotective, anti-inflammatory, anticancer, neuroprotective, and gestational actions.
  • 4.4K
  • 07 Apr 2023
Topic Review
Dimensionality of materials
As generally known dimensionality of materials is a crucial factor to determine functions and properties of the materials. In addition to zero-dimensional, one-dimensional, three-dimensional, and further integrated functional materials, various two-dimensional materials have been paid special attention. Two-dimensional materials have their unique electronic propertiesand play important roles in interfacial sciences.
  • 4.4K
  • 12 Aug 2021
Topic Review
Messaging Apps
Messaging apps (a.k.a. social messaging or chat applications) are apps and platforms that enable instant messaging. Messaging apps are online messaging services used primarily via mobile platforms. Many such apps have developed into broad platforms enabling status updates, chatbots, payments and conversational commerce (e-commerce via chat). They are normally centralised networks run by the servers of the platform's operators, unlike peer-to-peer protocols like XMPP. Some examples of popular messaging apps include WhatsApp, Facebook Messenger, China's WeChat and QQ Messenger, Telegram, Viber, Line, and Snapchat. The popularity of certain apps greatly differ between different countries. Certain apps have emphasis on certain uses - for example Skype focuses on video calling, Slack focuses on messaging and file sharing for work teams, and Snapchat focuses on image messages. Some social networking services offer messaging services as a component of their overall platform, such as Facebook's Facebook Messenger, while others have a direct messaging function as an additional adjunct component of their social networking platforms, like Instagram, Reddit, Tumblr, TikTok, Clubhouse and Twitter, either directly or through chat rooms. Messaging apps are the most widely used smartphone apps, with in 2018 over 1.3 billion monthly users of WhatsApp and Facebook Messenger, 980 million monthly active users of WeChat and 843 million monthly active users of QQ Mobile.
  • 4.4K
  • 09 Nov 2022
Topic Review
Backbone Chain
In polymer science, the backbone chain of a polymer is the longest series of covalently bonded atoms that together create the continuous chain of the molecule. This science is subdivided into the study of organic polymers, which consist of a carbon backbone, and inorganic polymers which have backbones containing only main group elements. In biochemistry, organic backbone chains make up the primary structure of macromolecules. The backbones of these biological macromolecules consist of central chains of covalently bonded atoms. The characteristics and order of the monomer residues in the backbone make a map for the complex structure of biological polymers (see Biomolecular structure). The backbone is, therefore, directly related to biological molecules’ function. The macromolecules within the body can be divided into four main subcategories, each of which are involved in very different and important biological processes: proteins, carbohydrates, lipids, and nucleic acids. Each of these molecules has a different backbone and consists of different monomers each with distinctive residues and functionalities. This is the driving factor of their different structures and functions in the body. Although lipids have a "backbone," they are not true biological polymers as their backbone is a three carbon molecule, glycerol, with longer substituent "side chains." For this reason, only proteins, carbohydrates, and nucleic acids should be considered as biological macromolecules with polymeric backbones.
  • 4.4K
  • 21 Nov 2022
Topic Review
Salt Stress on Plant Growth
Climate change is causing soil salinization, resulting in crop losses throughout the world. The ability of plants to tolerate salt stress is determined by multiple biochemical and molecular pathways. Here we discuss physiological, biochemical, and cellular modulations in plants in response to salt stress. Knowledge of these modulations can assist in assessing salt tolerance potential and the mechanisms underlying salinity tolerance in plants. Salinity-induced cellular damage is highly correlated with generation of reactive oxygen species, ionic imbalance, osmotic damage, and reduced relative water content. Accelerated antioxidant activities and osmotic adjustment by the formation of organic and inorganic osmolytes are significant and effective salinity tolerance mechanisms for crop plants. In addition, polyamines improve salt tolerance by regulating various physiological mechanisms, including rhizogenesis, somatic embryogenesis, maintenance of cell pH, and ionic homeostasis. 
  • 4.4K
  • 08 Jun 2021
Topic Review
Pakistan’s Heritage Management
Improving archaeology policies means fostering search and exploration of ancient sites, promoting protection and preservation actions of architectural remains, and management of cultural heritage.
  • 4.4K
  • 19 Apr 2022
Biography
Noor Muhammad
Noor Muhammad (15 April 1951 – 12 April 2004) was a notable Pakistani mathematician and mathematics writer who made an original contribution to the fields of C*-algebra, symmetric topology and pure mathematics. Noor Muhammad joined International Centre for Theoretical Physics on the request of prominent theoretical physics and nobel laureate in Physics Dr. Prof. Abdus Salam. As a post-doct
  • 4.4K
  • 30 Dec 2022
Topic Review
Niche Sport
Non-conventional sports that do not attract mass audiences
  • 4.4K
  • 21 Dec 2021
Topic Review
CO2 Activation on Catalyst Surfaces
Utilizing CO2 as a sustainable carbon source to form valuable products requires activating it by active sites on catalyst surfaces. These active sites are usually in or below the nanometer scale. Some metals and metal oxides in this scale dimension can catalyze the CO2 transformation reactions. Herein, CO2 activation on metal-based catalyst surfaces and how their structures impact the activation process are highlighted.
  • 4.4K
  • 13 Dec 2021
Topic Review
Virtual Power Plant Optimization in Smart Grids
Virtual power plants (VPPs) are promising solutions to address the decarbonization and energy efficiency goals in the smart energy grid. They assume the coordination of local energy resources such as energy generation, storage, and consumption. They are used to tackle problems brought by the stochastic nature of renewable energy, lack of energy storage devices, or insufficient local energy flexibility on the demand side. VPP modeling, management, and optimization are open to research problems that should consider, on one side, the local constraints in the operation of the energy resources and power flows and the energy grid’s sustainability objectives on the other side. There are multiple goals to create a VPP, such as to deliver energy services on a market or to the grid operator, to operate a microgrid in autonomy decoupled from the main grid, or to sustain local energy communities. 
  • 4.4K
  • 27 May 2022
Topic Review Peer Reviewed
Benefits of Table Tennis for Brain Health Maintenance and Prevention of Dementia
Table tennis is an extremely popular sport throughout the world as it requires no expensive equipment, specialized amenities, or physical contact among players, and the pace of play can be adapted to allow participation by players of all skill levels, ages, and abilities. It is an aerobic-dominant sport driven primarily by the phosphagen system because rallies are relatively brief (several seconds) and separated by longer rest periods. Several studies have shown that physical interventions including table tennis can help prevent cognitive decline and dementia. Accordingly, the present paper provides an overview of the basic physical and cognitive demands of table tennis, reviews previous studies reporting improvements in physical and brain health across different non-clinical and clinical populations, and critically evaluates the usefulness of table tennis intervention for the prevention of cognitive decline and dementia. This review suggests that table tennis intervention could be a powerful strategy to prevent cognitive decline and dementia in the elderly. 
  • 4.4K
  • 26 Sep 2022
Topic Review
Microgrids Configurations and Topologies
Microgrids have been proposed as a solution to the growing deterioration of traditional electrical power systems and the energy transition towards renewable sources. During the design of an microgrid (MG), the components and physical arrangement must be considered to achieve a proper transition between the different modes of operation. The connection of the loads, the microgenerators, and the storage elements, require rigorous analysis to obtain the operation and the desired efficiency by the network operator and the user. The way to interconnect all the elements of the network is known as MG topology.
  • 4.4K
  • 19 Apr 2022
Topic Review Video
Direct Carbon Fuel Cells
Most fuel cells invariably use gaseous or liquid fuels. A fuel cell technology that has attracted attention only recently, the direct carbon fuel cell (DCFC) uses solid fuel (carbon) and converts the chemical energy in the carbon to electricity through its direct participation in the fuel cell reactions and electrochemical oxidation. The fuel use can be almost 100% compared with about 85% for most other fuel cells. The electrical efficiency is expected to be above 70% - almost twice those of current generation coal-fired plants leading to 50% reduction in greenhouse gas emissions. The amount of CO2 for storage/sequestration is also halved. Moreover, the exit gas is almost pure carbon dioxide stream, requiring no or minimal gas separation and processing for sequestration. Therefore, the energy and cost penalties to capture the CO2 will be significantly less than for other technologies. However, the technology is at an early stage of development requiring many complex challenges to be overcome, related to materials and corrosion, fuel delivery mechanism, and system development, before it can be commercialized. Section 19.4 of a recent book by the author gives an overview of this technology focusing on its main issues (Sequeira, 2019.). Two of the main DCFCs, the direct carbon molten carbonate fuel cell (DC-MCFC) and the direct carbon solid oxide fuel cell (DC-SOFC) are described in this topic review. 
  • 4.4K
  • 04 Aug 2021
Topic Review
Nematode Identification
Nematodes are non-segmented roundworms evenly distributed with various habitats ranging to approximately every ecological extremity. These are the least studied organisms despite being the most diversified group. Nematodes are the most critical equilibrium-maintaining factors, having implications on the yield and health of plants as well as well-being of animals. As a result of the lack of precise taxonomic features, nematode taxonomy remains uncertain. Morphology-based identification has proved inefficacious in identifying and exploring the diversity of nematodes, as there are insufficient morphological variations. Different molecular and new evolving methodologies have been employed to augment morphology-based approaches and bypass these difficulties with varying effectiveness. These identification techniques vary from molecular-based targeting DNA or protein-based targeting amino acid sequences to methods for image processing. High-throughput approaches such as next-generation sequencing have also been added to this league. These alternative approaches have helped to classify nematodes and enhanced the base for increased diversity and phylogeny of nematodes, thus helping to formulate increasingly more nematode bases for use as model organisms to study different hot topics about human well-being.
  • 4.4K
  • 12 Jul 2022
Topic Review
Traditional Algal Transformation Techniques
Microalgae and cyanobacteria are photosynthetic microbes that can be grown with the simple inputs of water, carbon dioxide, (sun)light, and trace elements.
  • 4.4K
  • 12 Apr 2021
Topic Review
Land Use and Land Cover Mapping
The volume of collected or archived geospatial data for land use and land cover (LULC) mapping including remotely sensed satellite imagery and auxiliary geospatial datasets is increasing. Innovative machine learning, deep learning algorithms, and cutting-edge cloud computing have also been developed. While new opportunities are provided by these geospatial big data and advanced computer technologies for LULC mapping, challenges also emerge for LULC mapping from using these geospatial big data.
  • 4.4K
  • 17 Oct 2022
Topic Review
Walnut Oil
Walnut oil is extremely nutrient dense. It has plenty of oil and is high in fatty acids, which have positive biological properties and have a favorable impact on blood lipids and lipoproteins. Walnut oil is low in saturated fatty acids and high in unsaturated fatty acids as well as being high in other vital nutrients. Walnut oil can be extracted using traditional as well as new and green technologies.
  • 4.4K
  • 31 Dec 2022
Topic Review
Fat Leonard Scandal
The Fat Leonard scandal is a corruption scandal and ongoing investigation within the United States Navy involving ship support contractor Glenn Defense Marine Asia (GDMA), a subsidiary of the Glenn Marine Group. The Washington Post called the scandal "perhaps the worst national-security breach of its kind to hit the Navy since the end of the Cold War." At the heart of the scandal was Glenn Defense Marine Asia, a firm run by Leonard Glenn Francis, a Malaysian national known as "Fat Leonard" for his then over 350 pound weight. Francis provided at least a half million dollars in cash, plus travel expenses, luxury items, and prostitutes to a large number of U.S. uniformed officers of the United States Seventh Fleet, who in turn gave him classified material about the movements of U.S. ships and submarines, confidential contracting information, and information about active law enforcement investigations into Glenn Defense Marine Asia. Francis then "exploited the intelligence for illicit profit, brazenly ordering his moles to redirect aircraft carriers to ports he controlled in Southeast Asia so he could more easily bilk the Navy for fuel, tugboats, barges, food, water and sewage removal." The Navy, through GDMA, even employed divers to search harbors for explosives. He also directed them to author "Bravo Zulu" memos, which is an informal term for a letter of commendation from the Navy given to civilians who have performed outstanding services for the Navy, in order to bolster GDMA's credibility for jobs "well done". The first activities of the conspiracy were confirmed to have existed in 2006 when Francis recruited numerous Navy personnel to engage in corruption, including directing contracts toward his firm, disfavoring competitors, and inhibiting legitimate fiscal and operational oversight. The initial co-conspirators labelled themselves "the cool kids" and "the wolf pack." U.S. federal prosecutors filed criminal charges against 33 people in connection with the Fat Leonard scandal. Of those, 22 pleaded guilty: Francis himself, four of his top aides, and 17 Navy officials (specifically, at least ten commissioned officers, two petty officers, one former NCIS special agent, and two civilian Navy contracting officials). Nine others are awaiting trial in U.S. district court in San Diego. Separately, five Navy officers were charged with crimes under the Uniform Code of Military Justice (UCMJ) and have been subject to court-martial proceedings. An additional civilian pleaded guilty to a scandal-related crime in Singapore court. Suffering health problems, Francis was hospitalized and released in March 2018. Rather than returning to the custody of the U.S. Marshals Service, he was granted a medical furlough and allowed to stay in San Diego at a private residence owned by one of his physicians, under 24-hour surveillance for which his family paid. At a deposition taken in 2018 in the David A. Morales case, Francis said he is being treated for kidney cancer. In 1989, when he was 21, Francis had been sentenced to three years in jail in Malaysia for firearms possession.
  • 4.4K
  • 14 Oct 2022
Topic Review
Mean Field Theory
In physics and probability theory, mean-field theory (aka MFT or rarely self-consistent field theory) studies the behavior of high-dimensional random (stochastic) models by studying a simpler model that approximates the original by averaging over degrees of freedom. Such models consider many individual components that interact with each other. In MFT, the effect of all the other individuals on any given individual is approximated by a single averaged effect, thus reducing a many-body problem to a one-body problem. The main idea of MFT is to replace all interactions to any one body with an average or effective interaction, sometimes called a molecular field. This reduces any multi-body problem into an effective one-body problem. The ease of solving MFT problems means that some insight into the behavior of the system can be obtained at a lower computational cost. MFT has since been applied to a wide range of fields outside of physics, including statistical inference, graphical models, neuroscience, artificial intelligence, epidemic models, queueing theory, computer network performance and game theory, as in the Quantal response equilibrium.
  • 4.4K
  • 03 Nov 2022
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