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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
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
Screen-Printed Electrodes as Transducers
In the last decades, sensors based on screen-printed electrodes (SPEs) have gained increasing importance because of their advantageous characteristics, such as low-cost, disposability, ease of use and portability, which allow fast analysis in point-of-need scenarios. The main characteristics of SPEs as electrochemical transducers for biosensors are described below.
  • 1.8K
  • 13 Apr 2021
Topic Review
Polysaccharide-Based Aerogel Production
A comparative analysis concerning bio-based gels production, to be used for tissue regeneration, has been performed in this review. These gels are generally applied as scaffolds in the biomedical field, thanks to their morphology, low cytotoxicity, and high biocompatibility.
  • 1.8K
  • 17 May 2021
Topic Review
Time Series Aggregation for ESMs
Due to the high degree of intermittency of renewable energy sources and the growing interdependences amongst formerly separated energy pathways, the modeling of adequate energy systems is crucial to evaluate existing energy systems and to forecast viable future ones. However, this corresponds to the rising complexity of energy system models (ESMs) and often results in computationally intractable programs. To overcome this problem, time series aggregation is frequently used to reduce ESM complexity. As these methods aim at the reduction of input data and preserving the main information about the time series, but are not based on mathematically equivalent transformations, the performance of each method depends on the justifiability of its assumptions.
  • 1.8K
  • 29 Sep 2021
Biography
Dirk W Lachenmeier
Dr. Lachenmeier (ORCID 0000-0002-3115-864X) studied food chemistry (first state examination) at the University of Bonn (1994-1998), followed by position as first-year resident at various food control institutions in the State of North Rhine-Westfalia, concluding the studies with the second state examination and title of state-certified food chemist (Münster, 2000). He carried out his PhD in For
  • 1.8K
  • 27 Sep 2022
Topic Review
Cross-Country Mountain Biking
Mountain biking (MTB) is an off-road cycling discipline, performed on a course composed of a variety of unpaved terrain, which normally include technical or non-technical ascent, descent and flat (UCI regulations, Part 4 mountain bike, version from 11 February 2020). This modality can be practiced by people of all ages, male and female, from children to elderly in a recreational and/or professional manner. However, practitioners should be able to ride technique circuits usually composed of obstacles. For this, unlike road cycling, the bike is equipped with a shock absorption system and wider tires composed of shorter knobs in order to improve bicycle comfort and performance. The start (individual or in mass), duration and distance to be covered change according to each event. Normally, the competitions are played individually, but can also occur in teams (e.g., CAPE EPIC, South Africa, competed in pairs).
  • 1.8K
  • 20 Oct 2022
Topic Review
Converse (Logic)
In logic and mathematics, the converse of a categorical or implicational statement is the result of reversing its two constituent statements. For the implication P → Q, the converse is Q → P. For the categorical proposition All S are P, the converse is All P are S. Either way, the truth of the converse is generally independent from that of the original statement.
  • 1.8K
  • 27 Oct 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
Topic Review
Lithium Production and Recovery Methods
The first step of hydrometallurgical treatment is leaching, which is an effective method capable of transferring over 99% of the present metals to the leach solutions. Extraction of metals after leaching can be conducted using various methods, with precipitation being the most commonly used. The precipitation of other metals can result in the co-precipitation of lithium, causing total lithium losses up to 30%. To prevent such losses, solvent extraction methods are used to selectively remove elements, such as Co, Ni, Al, and Mn. Solvent extraction (SX) is highly effective, reducing the losses to 3% per extraction stage and reducing overall lithium losses to 15%. After the refining, lithium is precipitated as lithium carbonate. High lithium carbonate solubility (1.5 g/L) and high liquid to solid leaching ratios require costly and avoidable operations to be implemented in order to enhance lithium concentration. Therefore, it is suggested that more studies should focus on multistage leaching with lower L/S ratios.
  • 1.8K
  • 14 Jul 2023
Topic Review Peer Reviewed
The Social Aspect of Children and Adolescents with Chronic Respiratory Diseases
Chronic respiratory diseases (CRDs) are common among children and adolescents. Asthma and cystic fibrosis are two main conditions that affect this population. Young patients face physical limitations due to structural and functional abnormalities of the airways and other lung structures. Moreover, the route of everyday life is influenced by responsibilities derived from treatments, and exacerbations imposed by the disease impacting silently their social life. To date, discussions in the literature have mostly focused on the physical limitations that face children and adolescents. On the contrary, social aspects are less investigated, even their important role in rehabilitation patterns. On this basis, we provide an overview of the social determinants that affect children and adolescents with CRDs in different social environments, such as family and school; discuss coping strategies that can be developed to attenuate the impact of CRDs on youngsters’ lives; and present the role of healthcare professionals and digital technology in social support. 
  • 1.8K
  • 01 Jul 2025
Topic Review
Enhanced 9-1-1
Enhanced 911, E-911 or E911 is a system used in North America to automatically provide the caller's location to 911 dispatchers. 911 is the universal emergency telephone number in the region. In the European Union, a similar system exists known as E112 (where 112 is the emergency access number) and known as eCall when called by a vehicle. An incoming 911 call is routed to a Public Safety Answering Point (PSAP), which is a call center operated by the local government. At the PSAP, the call is answered by a specially trained official known as a 9-1-1 dispatcher. The dispatcher's computer receives information from the telephone company about the physical address (for landlines) or geographic coordinates (for wireless) of the caller. This information is used to dispatch police, fire, medical, and other services as needed.
  • 1.8K
  • 24 Oct 2022
Topic Review
Casein Kinase 1α
Wnt signaling regulates numerous cellular processes during embryonic development and adult tissue homeostasis. Underscoring this physiological importance, deregulation of the Wnt signaling pathway is associated with many disease states, including cancer. Here, we review pivotal regulatory events in the Wnt signaling pathway that drive cancer growth. We then discuss the roles of the established negative Wnt regulator, casein kinase 1α (CK1α), in Wnt signaling. Although the study of CK1α has been ongoing for several decades, the bulk of such research has focused on how it phosphorylates and regulates its various substrates. We focus here on what is known about the mechanisms controlling CK1α, including its putative regulatory proteins and alternative splicing variants. Finally, we describe the discovery and validation of a family of pharmacological CK1α activators capable of inhibiting Wnt pathway activity. One of the important advantages of CK1α activators, relative to other classes of Wnt inhibitors, is their reduced on-target toxicity, overcoming one of the major impediments to developing a clinically relevant Wnt inhibitor. Therefore, we also discuss mechanisms that regulate CK1α steady-state homeostasis, which may contribute to the deregulation of Wnt pathway activity in cancer and underlie the enhanced therapeutic index of CK1α activators. 
  • 1.8K
  • 26 Oct 2020
Topic Review
Grazing and Feedlot Angus Beef Cattle
Grazing-fed cattle are free-ranged on pastures with grass as the main feed, while feedlot-fed cattle are raised in feedlots with grains as their main feed. 
  • 1.8K
  • 22 Nov 2021
Topic Review
5-Hydroxytryptamine Receptors
5-Hydroxytryptamine (5-HT) receptors, also referred to as serotonin receptors, are a monoamine receptor molecule, activated by the neurotransmitter serotonin.
  • 1.8K
  • 30 Dec 2021
Topic Review
Feeding Problems in Patients with Noonan Syndrome
Noonan syndrome (NS) belongs to the group of Noonan syndrome spectrum disorders (NSSD), which is a group of phenotypically related conditions. Feeding problems are often present not only in infancy but also in childhood, and even beyond that period. More than 50% of infants with NS develop feeding problems, and up to half of these infants will be tube-dependent for some time. Although, in general, there is a major improvement between the age of 1 and 2 years, with only a minority still having feeding problems after the age of 2 years, as long as the feeding problems continue, the impact on the quality of life of both NS infants and their caregivers may be significant. Feeding problems in general improve faster in children with a pathogenic PTPN11 or SOS1 variant. The mechanism of the feeding problems is complex, and may be due to medical causes (gastroesophageal reflux disease and delayed gastric emptying, cardiac disease and infections), feeding-skill dysfunction, nutritional dysfunction with increased energy demand, or primary or secondary psychosocial dysfunction. Many of the underlying mechanisms are still unknown. The treatment of the feeding problems may be a medical challenge, especially when the feeding problems are accompanied by feeding-skill dysfunction and psychosocial dysfunction. 
  • 1.8K
  • 17 Feb 2022
Topic Review
Zeaxanthin and Lutein Across Life's Taxa
Zeaxanthin and lutein are structural isomers with zeaxanthin possessing a slightly longer system of conjugated double bonds (11) than lutein. Carotenoids also play key roles in light-independent processes, e.g., as gene regulators of human immune function. Carotenoid-derived vitamin A has a well-documented immunoregulatory role and a similar role is emerging for xanthophylls. Xanthophylls may be especially important in opposing non-resolving inflammation that can trigger a plethora of associated inflammatory diseases, disorders, and dysfunctions. Additionally, lutein and zeaxanthin are emerging as candidates for protecting cognitive function across the human lifespan, including attention, memory, learning, and executive functions.
  • 1.8K
  • 28 Apr 2022
Biography
Janet Dean Fodor
Janet Dean Fodor (born 1942) is distinguished professor of linguistics at the City University of New York.[1] Her primary field is psycholinguistics,[2] and her research interests include human sentence processing, prosody, learnability theory and L1 (first-language) acquisition.[1][3] Born Janet Dean, she grew up in England and received her B.A. in 1964 and her M.A. in 1966, both from Oxford
  • 1.8K
  • 02 Dec 2022
Topic Review
Impact of Artificial Intelligence on the Job Market
This research explores the impact of artificial intelligence (AI) on the job market, including both its potential benefits and drawbacks. The research discusses how AI can automate repetitive tasks, improve accuracy, and assist workers in performing their jobs more effectively. However, the article also highlights concerns about job displacement, biases and discrimination, and the deskilling of workers. The research examines the impact of AI on different industries and types of jobs and discusses the need for workers to develop complementary skills and for employers to invest in AI technologies that work collaboratively with human workers. The research concludes by highlighting the importance of investing in education and training programs, ensuring ethical and transparent development and deployment of AI, and implementing appropriate policies to support workers who are displaced by AI.
  • 1.8K
  • 22 May 2023
Topic Review
Multidimensional Chromatography and Its Applications
Food, drugs, dyes, extracts, and minerals are all made up of complex elements, and utilizing unidimensional chromatography to separate them is inefficient and insensitive. This has sparked the invention of several linked chromatography methods, each of them with distinct separation principles and affinity for the analyte of interest. Multidimensional chromatography consists of the combination of multiple chromatography techniques, with great benefits at the level of efficiency, peak capacity, precision, and accuracy of the analysis, while reducing the time required for the analysis.
  • 1.8K
  • 14 Nov 2022
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