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Topic Review
The Ubiquity of Microplastics in the Environment
Plastic is an indispensable material in modern society; however, high production rates combined with inadequate waste management and disposal have resulted in enormous stress on ecosystems. In addition, plastics can become smaller particles known as microplastics (MPs) due to physical, chemical, and biological drivers. MP pollution has become a significant environmental problem affecting terrestrial and aquatic ecosystems worldwide.
  • 1.8K
  • 28 Aug 2023
Topic Review
Silk Proteins with Metal Ions and Factors
Silk secreted by Bombyx mori L. silkworm has become one of the most important biomaterials, due to its excellent biocompatibility, controllable biodegradability, superior processability, and unique mechanical properties. Silk fibroin and sericin, as the two components of silk, contain abundant polar functional groups, and thus can bind metal ions through electrostatic interaction and chelation.
  • 1.8K
  • 28 Nov 2023
Topic Review
Endogenous Retroviruses
Endogenous retroviruses (ERVs) are long terminal repeat (LTR)-retroelements of the Retroviridae genus. ERVs reside in vertebrate genomes, are particularly abundant in mammals, and still actively retrotranspose in mice. This entry describes their relationship to other LTR-retroelements and how they replicate. A brief introduction into epigenetic reprogramming of ERVs is followed by a few examples of how reprogramming of ERVs assists embryonic development in mouse and human.
  • 1.8K
  • 26 Oct 2020
Topic Review
Silicon Multi-Mode Routing Devices
The multi-mode routing devices are used for transferring higher-order modes in the multi-mode bus waveguide without introducing mode-dependent losses or inter-modal crosstalk, including multi-mode bend, multi-mode crossing and multi-mode splitter.
  • 1.8K
  • 29 Sep 2020
Topic Review
Extracellular Signal-Regulated Kinase
Extracellular signal-regulated kinase (ERK5) is an essential regulator of cancer progression, tumor relapse, and poor patient survival. Epithelial to mesenchymal transition (EMT) is a complex oncogenic process, which drives cell invasion, stemness, and metastases. Activators of ERK5, including mitogen-activated protein kinase 5 (MEK5), tumor necrosis factor α (TNF-α), and transforming growth factor-β (TGF-β), are known to induce EMT and metastases in breast, lung, colorectal, and other cancers. Several downstream targets of the ERK5 pathway, such as myocyte-specific enhancer factor 2c (MEF2C), activator protein-1 (AP-1), focal adhesion kinase (FAK), and c-Myc, play a critical role in the regulation of EMT transcription factors SNAIL, SLUG, and β-catenin. Moreover, ERK5 activation increases the release of extracellular matrix metalloproteinases (MMPs), facilitating breakdown of the extracellular matrix (ECM) and local tumor invasion. Targeting the ERK5 signaling pathway using small molecule inhibitors, microRNAs, and knockdown approaches decreases EMT, cell invasion, and metastases via several mechanisms.
  • 1.8K
  • 20 Feb 2021
Topic Review
DNA Methylation and AP-1 Signaling
Epigenetic regulation and modification govern the transcriptional mechanisms that promote disease initiation and progression, but can also control the oncogenic processes, cell signaling networks, immunogenicity, and immune cells involved in anti-inflammatory and anti-tumor responses. 
  • 1.8K
  • 27 Mar 2021
Topic Review
HANPP
Human appropriation of net primary production (HANPP) is a substantial improvement upon 20th century attempts at developing an ecological footprint indicator because of its measurability in relation to net primary production, its close relationship to other key footprint measures, such as carbon and water, and its spatial specificity. HANPP informs different sustainability narratives at different scales. At the planetary scale, HANPP is a critical planetary limit that improves upon areal land use indicators. At the country macroscale, HANPP indicates the degree to which meeting the needs of the domestic population for provisioning ecosystem services (food, feed, biofiber, biofuel) presses against the domestic ecological endowment of net primary production. At the county mesoscale, HANPP reveals the dependency of metropolitan areas upon regional specialized rural forestry and agroecosystems to which they are teleconnected through trade and transport infrastructures. At the pixel microscale, HANPP provides the basis for deriving spatial patterns of remaining net primary production upon which biodiversity and regulatory and cultural ecosystem services are dependent. HANPP is thus a sustainability indicator that can fulfill similar needs as carbon, water and other footprints.
  • 1.8K
  • 23 Aug 2021
Topic Review
Hyperinsulinaemia-Osteofragilitas
Bone fragility leading to increased risk of low energy (fragility) fractures that is independent of bone mineral density, occurring in individuals with detected and undetected hyperinsulinaemia. Patients with type 2 diabetes mellitus (T2DM) and/or cardiovascular disease (CVD), conditions of hyperinsulinaemia, have lower levels of osteocalcin and bone remodelling, and increased rates of fragility fractures. Unlike osteoporosis with lower bone mineral density (BMD), T2DM bone fragility “hyperinsulinaemia-osteofragilitas” phenotype presents with normal to increased BMD. Hyperinsulinaemia and insulin resistance positively associate with increased BMD and fragility fractures.  Hyperinsulinaemia enforces glucose fuelling, which decreases NAD+-dependent antioxidant activity. This increases reactive oxygen species and mitochondrial fission, and decreases oxidative phosphorylation high-energy production capacity, required for osteoblasto/cytogenesis. Osteocytes directly mineralise and resorb bone, and inhibit mineralisation of their lacunocanalicular space via pyrophosphate. Hyperinsulinaemia decreases vitamin D availability via adipocyte sequestration, reducing dendrite connectivity, and compromising osteocyte viability. Decreased bone remodelling and micropetrosis ensues. Trapped/entombed magnesium within micropetrosis fossilisation spaces propagates magnesium deficiency (MgD), potentiating hyperinsulinaemia and decreases vitamin D transport. Vitamin D deficiency reduces osteocalcin synthesis and favours osteocyte apoptosis.  Carbohydrate restriction/fasting/ketosis increases beta-oxidation, ketolysis, NAD+-dependent antioxidant activity, osteocyte viability and osteocalcin, and decreases excess insulin exposure. Osteocalcin is required for hydroxyapatite alignment, conferring bone structural integrity, decreasing fracture risk and improving metabolic/endocrine homeodynamics. Patients presenting with fracture and normal BMD should be investigated for T2DM and hyperinsulinaemia.
  • 1.8K
  • 09 Oct 2021
Topic Review
Glyphosate in Food
Glyphosate is a systemic, broad-spectrum and post-emergent herbicide. The use of glyphosate has grown in the last decades, and it is currently the most used herbicide worldwide. The rise of glyphosate consumption over the years also brought an increased concern about its possible toxicity and consequences for human health. 
  • 1.8K
  • 19 Nov 2021
Topic Review
Product–Service Systems for supply management of spare parts
A Product–Service System (PSS) can be considered as a combination of customer life cycle-oriented products and services that are provided by means of an extended value creation network. Such a business model fosters the transition from a tangible goods-dominant logic to an intangible goods-dominant one and accomplishes Circular Economy (CE) principles. In fact, the services interwoven with a product’s life cycle, especially those related to its use and End-Of-Life (EOL) phases, play a crucial role in the optimization of the environmental performances of a product through its whole life cycle. However, PSS solutions aimed at practically optimizing supply chain management have scarcely been addressed. In order to reduce this gap, here proposes a procedure based on the PSS Functional Matrix, the Screening Life Cycle Modelling (SLCM) method, and stock management theory to optimize aftermarket services based on market demand.
  • 1.8K
  • 04 Mar 2022
Topic Review
Primary Polydipsia
Primary polydipsia, or psychogenic polydipsia, is a form of polydipsia characterised by excessive fluid intake in the absence of physiological stimuli to drink. Psychogenic polydipsia which is caused by psychiatric disorders, often schizophrenia, is often accompanied by the sensation of dry mouth. Some forms of polydipsia are explicitly non-psychogenic. Primary polydipsia is a diagnosis of exclusion.
  • 1.8K
  • 22 Nov 2022
Topic Review
Non-Deterministic Turing Machine
In theoretical computer science, a Turing machine is a theoretical machine that is used in thought experiments to examine the abilities and limitations of computers.
  • 1.8K
  • 28 Nov 2022
Topic Review
Caster
A caster (also known as castor according to some dictionaries) is a wheeled device typically mounted to a larger object that enables relatively easy rolling movement of the object. Casters are essentially housings, that include a wheel and a mounting to install the caster to objects (equipment, apparatus and more). Casters are found virtually everywhere, from office desk chairs to shipyards, and from hospital beds to automotive factories. They range in size from the very small furniture casters to massive industrial casters, and individual load capacities span 100 pounds (45 kg) or less to 100,000 pounds (45 t). Wheel materials include cast iron, plastic, rubber, polyurethane, polyolefin, nylon, thermoplastic rubber, forged steel, stainless steel, aluminum, and more.
  • 1.8K
  • 25 Nov 2022
Topic Review
T2DM and the Gut Microbiota
Type 2 Diabetes Mellitus (T2DM) affects over 9% of the United States population alone, constitutes a cause for ensuing cardiovascular disease, and is typically closely linked to obesity status. While obesity has long been perceived to stem from a sedentary lifestyle and high fat intake there is increasing evidence supporting the idea that this is a more complex issue than initially thought. The human gut microbiome has been a recent point of investigation due to the idea that it may be closely linked to T2DM. The aforementioned high fat diets can impact the gut microbiome in a significant way, altering the demography of the gut’s microflora, hence shifting the gut into a state of dysbiosis. Dysbiosis is a state that favors the initiation of a cascade inducing metabolic deregulation, increasing inflammation and insulin resistance systemically. Below the relationship of the microbiome to T2DM is briefly discussed.
  • 1.8K
  • 29 Oct 2020
Topic Review
Mobile Learning
Abstract: Mobile phones have become widespread in the modern era. One contemporary use of mobile phones is in the education field, commonly known as M-Learning. Subsequent to the growth of M-Learning, developers of educational mobile applications need to understand what the user requirements are, and how to satisfy them. In order to measure user satisfaction while engaging with mobiles aslearning tools, manymodelshavebeencreatedusingtheUnifiedTheoryofAcceptanceand Use of Technology, and other models such as the Technology Acceptance Model. However, none of these has focused on the technical factors affecting the users’ intentions to use their mobile phones as learning tools. Due to technical limitations, as well as human psychology, mobile phone learning remains limited to an assistance-only function. This paper presents a review of studies that have been used to measure users’ intentions of engaging with mobile phones as learning tools. One hundred and twenty-seven papers have been reviewed, dating from 2011 to 2020. These papers differ in terms of methodology and results collected. Results showed that many models had been extended by adding factors such as trust, pre-usage or attitude. Moreover, this review concludes that almost none of the above-mentioned studies had identified precisely the technical factors that may affect the intention of using this type of technology in education. However, when classifying the influential factors of M-Learning, almost none of the studies discussed the advantages of the technical aspect in imparting knowledge through mobile learning. This study is significant for the education industry in its identification of the relative importance of these factors where mobiles are involved in the learning process. In addition, it provides a brief history of the involvement of technology in education.
  • 1.8K
  • 10 Feb 2021
Topic Review
Vitamin C and Kidney Injury
Vitamin C is an important micronutrient and antioxidant for the human body.  In animal experiments, it can protect the kidneys from injury caused by nephrotoxic drugs.  A major feature of COVID-19 and similar viral infection is the cytokine storm, which causes a rise of multiple cytokines in the blood. Those cytokines result in the oxidative stress in cells, which leads to damage to organs and tissues, including the kidneys.  Here, we reviewed the current literature on kidney damage in COVID-19 patients and analyzed the possible etiology and mechanisms.  In addition, we summarized the potential use of vitamin C in preventing kidney damage in experimental animal models and the underlying mechanisms.  Vitamin C appears to protect and facilitate recovery of kidneys from injuries derived from excessive of oxidative stress, a feature of cytokines storm in people with COVID-19.  Finally, we would like to argue that vitamin C may be protective of the renal functions in COVID-19 patients with pre-existing kidney diseases. 
  • 1.8K
  • 26 Jul 2021
Topic Review
Personalized Learning
Personalized learning, individualized instruction, personal learning environment and direct instruction all refer to efforts to tailor education to meet the different needs of students.
  • 1.8K
  • 31 Oct 2022
Topic Review
Biological Activity of Cobalt Nanomaterials against Infectious Diseases
Infectious diseases remain the most serious public health issue, which requires the development of more effective strategies for infectious control. As a kind of ultra-trace element, cobalt is essential to the metabolism of different organisms. Nanotechnology has attracted increasing attention worldwide due to its wide application in different areas, including medicine. Based on the important biological roles of cobalt, cobalt nanomaterials have recently been widely developed for their attractive biomedical applications. With advantages such as low costs in preparation, hypotoxicity, photothermal conversion abilities, and high drug loading ability, cobalt nanomaterials have been proven to show promising potential in anticancer and anti-infection treatment.
  • 1.8K
  • 15 Nov 2022
Topic Review
9Dragons
9Dragons is a martial arts-themed massively multiplayer online role playing game, developed by Korean video game company Indy21. The game features 3D graphics and traditional Massively multiplayer online game control schemes. Set in China during the Ming Dynasty, it includes actual Chinese geography and historical features such as the Great Wall of China and the famous Shaolin Monastery.
  • 1.8K
  • 17 Nov 2022
Topic Review
Immunity (Medical)
In biology, immunity is the capability of multicellular organisms to resist harmful microorganisms. Immunity involves both specific and nonspecific components. The nonspecific components act as barriers or eliminators of a wide range of pathogens irrespective of their antigenic make-up. Other components of the immune system adapt themselves to each new disease encountered and can generate pathogen-specific immunity. Immunity is a complex biological system that can recognize and tolerate whatever belongs to the self, and to recognize and reject what is foreign (non-self).
  • 1.8K
  • 23 Nov 2022
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