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Topic Review
Polymers in Wastewater Treatment
The utilization of various types of natural and modified polymers for removing toxicant dyes in wastewater generated by the dye industry is reviewed in this article. Dye wastewater contains large amounts of metals, surfactants, and organic matter, which have adverse effects on human health, potentially causing skin diseases and respiratory problems. The removal of dyes from wastewaters through chemical and physical processes has been addressed by many researchers. Currently, the use of natural and modified polymers for the removal of dyes from wastewater is becoming more common. Although modified polymers are preferred for the removal of dyes, due to their biodegradability and non-toxic nature, large amounts of polymers are required, resulting in higher costs. 
  • 5.5K
  • 20 Oct 2020
Topic Review
Bio-Oil
Bio-oil is a the liquid phase obtained from the pyrolysis of biomass. The composition and amount of bio-oil generated depend not only on the type of the biomass but also on the conditions under which pyrolysis is performed. Most fossil fuels can be replaced by bio-oil-derived products. Thus, bio-oil can be used directly or co-fed along with fossil fuels in boilers, transformed into fuel for car engines by hydrodeoxygenation or even used as a more suitable source for hydrogen production than biomass. On the other hand, due to its rich composition in compounds resulting from the pyrolysis of cellulose, hemicellulose and lignin, bio-oil co-acts as a source of various value-added chemicals such as aromatic compounds.
  • 5.5K
  • 12 May 2021
Topic Review
Sunday Shopping
Sunday shopping, also called Sunday trading, refers to the ability of retailers to operate stores on Sunday, a day that Christian tradition typically recognises as a day of rest. Rules governing shopping hours, such as Sunday shopping, vary around the world and some countries and subnational jurisdictions ban or restrict Sunday shopping.
  • 5.5K
  • 22 Nov 2022
Topic Review
Cyanophyceae
Cyanobacteria (/saɪˌænoʊbækˈtɪəri.ə/), also known as Cyanophyta, are a phylum of Gram-negative bacteria that obtain energy via photosynthesis. The name cyanobacteria refers to their color (from grc κυανός (kuanós) 'blue'), which similarly forms the basis of cyanobacteria's common name, blue-green algae.[note 1] They appear to have originated in a freshwater or terrestrial environment. Sericytochromatia, the proposed name of the paraphyletic and most basal group, is the ancestor of both the non-photosynthetic group Melainabacteria and the photosynthetic cyanobacteria, also called Oxyphotobacteria. Cyanobacteria use photosynthetic pigments, such as carotenoids, phycobilins, and various forms of chlorophyll, which absorb energy from light. Unlike heterotrophic prokaryotes, cyanobacteria have internal membranes. These are flattened sacs called thylakoids where photosynthesis is performed. Phototrophic eukaryotes such as green plants perform photosynthesis in plastids that are thought to have their ancestry in cyanobacteria, acquired long ago via a process called endosymbiosis. These endosymbiotic cyanobacteria in eukaryotes then evolved and differentiated into specialized organelles such as chloroplasts, chromoplasts, etioplasts, and leucoplasts, collectively known as plastids. Cyanobacteria are the first organisms known to have produced oxygen. By producing and releasing oxygen as a byproduct of photosynthesis, cyanobacteria are thought to have converted the early oxygen-poor, reducing atmosphere into an oxidizing one, causing the Great Oxidation Event and the "rusting of the Earth", which dramatically changed the composition of the Earth's life forms. The cyanobacteria Synechocystis and Cyanothece are important model organisms with potential applications in biotechnology for bioethanol production, food colorings, as a source of human and animal food, dietary supplements and raw materials. Cyanobacteria produce a range of toxins known as cyanotoxins that can pose a danger to humans and animals.
  • 5.5K
  • 01 Nov 2022
Topic Review
Muhajir People
The Muhajir people (also spelled Mahajir and Mohajir) (Urdu: مہاجر‎) are Muslim immigrants, of multi-ethnic origin, and their descendants, who migrated from various regions of India after the Partition of India to settle in the newly independent state of Pakistan . The term Muhajirs refers to those Muslim migrants from India who mostly settled in urban Sindh.
  • 5.5K
  • 29 Nov 2022
Topic Review
Autonomous Navigation
Autonomous navigation is a very important area in the huge domain of mobile autonomous vehicles.  Sensor integration is a key concept that is critical to the successful implementation of navigation.  As part of this publication, we review the integration of Laser sensors like LiDAR with vision sensors like cameras.  The past decade, has witnessed a surge in the application of sensor integration as part of smart-autonomous mobility systems. Such systems can be used in various areas of life like safe mobility for the disabled, disinfecting hospitals post Corona virus treatments, driver-less vehicles, sanitizing public areas, smart systems to detect deformation of road surfaces, to name a handful.  These smart systems are dependent on accurate sensor information in order to function optimally. This information may be from a single sensor or a suite of sensors with the same or different modalities. We review various types of sensors, their data, and the need for integration of the data with each other to output the best data for the task at hand, which in this case is autonomous navigation. In order to obtain such accurate data, we need to have optimal technology to read the sensor data, process the data, eliminate or at least reduce the noise and then use the data for the required tasks. We present a survey of the current data processing techniques that implement integration of multimodal data from different types of sensors like LiDAR that use light scan technology, various types of Red Green Blue (RGB) cameras that use optical technology and review the efficiency of using fused data from multiple sensors rather than a single sensor in autonomous navigation tasks like mapping, obstacle detection, and avoidance or localization. This survey will provide sensor information to researchers who intend to accomplish the task of motion control of a robot and detail the use of LiDAR and cameras to accomplish robot navigation
  • 5.5K
  • 30 Oct 2020
Topic Review
High Entropy Alloys
High-entropy alloys (HEAs) are alloys that are formed by mixing equal or relatively large proportions of (usually) five or more elements. Prior to the synthesis of these substances, typical metal alloys comprised one or two major components with smaller amounts of other elements. For example, additional elements can be added to iron to improve its properties, thereby creating an iron based alloy, but typically in fairly low proportions, such as the proportions of carbon, manganese, and the like in various steels. Hence, high entropy alloys are a novel class of materials. The term “high-entropy alloys” was coined because the entropy increase of mixing is substantially higher when there is a larger number of elements in the mix, and their proportions are more nearly equal. These alloys are currently the focus of significant attention in materials science and engineering because they have potentially desirable properties. Furthermore, research indicates that some HEAs have considerably better strength-to-weight ratios, with a higher degree of fracture resistance, tensile strength, as well as corrosion and oxidation resistance than conventional alloys. Although HEAs have been studied since the 1980s, research substantially accelerated in the 2010s.
  • 5.5K
  • 01 Dec 2022
Topic Review Peer Reviewed
Mechanics and Mathematics in Ancient Greece
This entry presents an overview on how mechanics in Greece was linked to geometry. In ancient Greece, mechanics was about lifting heavy bodies, and mathematics almost coincided with geometry. Mathematics interconnected with mechanics at least from the 5th century BCE and became dominant in the Hellenistic period. The contributions by thinkers such as Aristotle, Euclid, and Archytas on fundamental problems such as that of the lever are sketched. This entry can be the starting point for a deeper investigation on the connections of the two disciplines through the ages until our present day.
  • 5.5K
  • 13 Apr 2022
Topic Review
Deontological Ethics
In moral philosophy, deontological ethics or deontology (from Greek: Ancient Greek: + Ancient Greek:) is the normative ethical theory that the morality of an action should be based on whether that action itself is right or wrong under a series of rules, rather than based on the consequences of the action. It is sometimes described as duty-, obligation-, or rule-based ethics. Deontological ethics is commonly contrasted to consequentialism, virtue ethics, and pragmatic ethics. In this terminology, action is more important than the consequences. The term deontological was first used to describe the current, specialised definition by C. D. Broad in his 1930 book, Five Types of Ethical Theory. Older usage of the term goes back to Jeremy Bentham, who coined it prior to 1816 as a synonym of dicastic or censorial ethics (i.e., ethics based on judgement). The more general sense of the word is retained in French, especially in the term code de déontologie (ethical code), in the context of professional ethics. Depending on the system of deontological ethics under consideration, a moral obligation may arise from an external or internal source, such as a set of rules inherent to the universe (ethical naturalism), religious law, or a set of personal or cultural values (any of which may be in conflict with personal desires).
  • 5.5K
  • 16 Nov 2022
Topic Review
Classes of Transposable Elements
Transposable elements (TEs) are mobile genetic elements that constitute a sizeable portion of many eukaryotic genomes. Through their mobility, they represent a major source of genetic variation, and their activation can cause genetic instability and has been linked to aging, cancer and neurodegenerative diseases.
  • 5.5K
  • 23 Sep 2022
Topic Review
Smoothies
The word “smoothie” comes from the English term “smooth” (tender, creamy), and defines a creamy non-alcoholic drink with a thick texture similar to that of milkshakes. Smoothies are beverages containing a blend of fruit pulp, fruit juice, ice, yoghurt, and/or milk. This beverage includes only natural ingredients such as puree fruit with fruit juice, and possibly dairy products or/and crushed ice cubes. Their preparation is based on the use of the entire fruit, which is processed from pulp to puree, with only the seeds and peel being removed.
  • 5.5K
  • 26 Sep 2020
Topic Review Peer Reviewed
Japanese Prefabricated Housing Manufacturers
Japanese prefabricated housing manufacturers have gained international recognition for their innovative approaches to the whole design process, ranging from initial design to innovative cutting-edge technologies, state-of-the-art automated production lines, meticulous workmanship, and mass customisation. In this entry, three manufacturers (Daiwa House, Sekisui House, and Misawa Homes) were selected as case studies for close examination. By studying these leading companies, researchers and industry professionals can gain valuable insights into best practices, challenges, and innovations within the Japanese prefabricated housing sector. The research methods involved a desktop study of available information on websites, articles, and reports, as well as undertaking two study tours on residential sustainable design in Japan in 2022 and 2023. These three manufacturers were discussed and compared with respect to their development trajectories, design customisation, research capabilities and technological advancements, sustainable initiatives and procurement, as well as their after-sale services. They have demonstrated their adaptability and flexibility in response to natural disasters and the transformation of the needs in society. They are all keen on reducing the environmental impacts of their work towards zero carbon emissions and a sustainable future.
  • 5.5K
  • 12 Jul 2024
Topic Review
Applications of Nanostructured Materials
In the last few decades, the vast potential of nanomaterials for biomedical and healthcare applications has been extensively investigated. Several case studies demonstrated that nanomaterials can offer solutions to the current challenges of raw materials in the biomedical and healthcare fields. The different nanoparticles and nanostructured material synthesis approaches were described.
  • 5.5K
  • 11 Apr 2022
Topic Review
Food Wastes as Packaging Materials
Packaging materials have to allow controlled respiration, maintain polymer structure against mechanical damage, prevent microbiological and chemical spoilage of food, and act as a selective gas and water vapor barrier. The most widely used materials in the food packaging industry are glass, plastics, metals, and paper. As mechanical properties of materials are important for food protection, mostly flexible and rigid synthetic packaging materials are preferred.
  • 5.5K
  • 19 Aug 2021
Topic Review
New Guinea Highlands
The New Guinea Highlands, also known as the Central Range or Central Cordillera, is a long chain of mountain ranges on the island of New Guinea, including the island's tallest peak, Puncak Jaya 16,024 ft (4,884 m), the highest mountain in Oceania. The range is home to many intermountain river valleys, many of which support thriving agricultural communities. The highlands run generally east-west the length of the island, which is divided politically between Indonesia in the west and Papua New Guinea in the east.
  • 5.5K
  • 09 Nov 2022
Topic Review
Late Devonian Extinction
The Late Devonian extinction was one of five major extinction events in the history of life on Earth. A major extinction, the Kellwasser event, occurred at the boundary that marks the beginning of the last phase of the Devonian period, the Famennian faunal stage (the Frasnian–Famennian boundary), about 376–360 million years ago. Overall, 19% of all families and 50% of all genera became extinct. A second, distinct mass extinction, the Hangenberg event, closed the Devonian period. Although it is clear that there was a massive loss of biodiversity in the Late Devonian, the timespan of this event is uncertain, with estimates ranging from 500,000 to 25 million years, extending from the mid-Givetian to the end-Famennian. Nor is it clear whether there were two sharp mass extinctions or a series of smaller extinctions, though the latest research suggests multiple causes and a series of distinct extinction pulses during an interval of some three million years. Some consider the extinction to be as many as seven distinct events, spread over about 25 million years, with notable extinctions at the ends of the Givetian, Frasnian, and Famennian stages. By the Late Devonian, the land had been colonized by plants and insects. In the oceans were massive reefs built by corals and stromatoporoids. Euramerica and Gondwana were beginning to converge into what would become Pangaea. The extinction seems to have only affected marine life. Hard-hit groups include brachiopods, trilobites, and reef-building organisms; the reef-building organisms almost completely disappeared. The causes of these extinctions are unclear. Leading hypotheses include changes in sea level and ocean anoxia, possibly triggered by global cooling or oceanic volcanism. The impact of a comet or another extraterrestrial body has also been suggested, such as the Siljan Ring event in Sweden. Some statistical analysis suggests that the decrease in diversity was caused more by a decrease in speciation than by an increase in extinctions. This might have been caused by invasions of cosmopolitan species, rather than by any single event. Surprisingly, jawed vertebrates seem to have been unaffected by the loss of reefs or other aspects of the Kellwasser event, while agnathans were in decline long before the end of the Frasnian.
  • 5.5K
  • 30 Nov 2022
Topic Review
Vanillin Production from Lignin
Vanillin, one of the most widely used and appreciated flavoring agents worldwide, is the main constituent of vanilla bean extract, obtained from the seed pods of various members belonging to the Orchidaceae family. Due to the great demand in the food confectionery industry, as well as in the perfume industry, medicine, and more, the majority of vanillin used today is produced synthetically, and only less than one percent of the world’s vanilla flavoring market comes directly from the traditional natural sources. The increasing global demand for vanillin requires alternative and overall sustainable new production methods, and the recovery from biobased polymers, like lignin, is an environmentally friendly alternative to chemical synthesis. 
  • 5.5K
  • 01 Feb 2024
Topic Review
Preparation of Nanofluids
There are two different ways of preparing nanofluids categorized in a one-step process and a two-step process. The origin of the word “nanofluid” is connected with the work by Choi et al. back in 1995, where they researched enhancement of thermal conductivity of fluids mixed with nanoparticles, determined the direction of further research, described the theoretical study of these fluids, and set potential benefits of nanofluids. From that point, the number of scientific papers that deal with nanofluids has been exponentially increasing. 
  • 5.5K
  • 22 Nov 2021
Topic Review
Major Histocompatibility Complex Class II Presentation in Autoimmunity
Antigen presentation by major histocompatibility complex class II (MHC-II) molecules is crucial for eliciting an efficient immune response by CD4+ T cells and maintaining self-antigen tolerance. Some MHC-II alleles are known to be positively or negatively associated with the risk of the development of different autoimmune diseases (ADs), including those characterized by the emergence of autoreactive T cells. Apparently, the MHC-II presentation of self-antigens contributes to the autoimmune T cell response, initiated through a breakdown of central tolerance to self-antigens in the thymus. 
  • 5.5K
  • 02 Feb 2023
Topic Review
Spray freeze-drying in pharmaceutical products
Pharmaceutical manufacturing is evolving from traditional batch processes to continuous ones. The present review deals with the most recent technologies, based on spray freeze-drying, that can achieve this objective. It provides a comprehensive overview of the physics behind this process and of the most recent equipment design.
  • 5.5K
  • 27 Oct 2020
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