Your browser does not fully support modern features. Please upgrade for a smoother experience.
Subject:
All Disciplines Arts & Humanities Biology & Life Sciences Business & Economics Chemistry & Materials Science Computer Science & Mathematics Engineering Environmental & Earth Sciences Medicine & Pharmacology Physical Sciences Public Health & Healthcare Social Sciences
Sort by:
Most Viewed Latest Alphabetical (A-Z) Alphabetical (Z-A)
Filter:
All Topic Review Biography Peer Reviewed Entry Video Entry
Topic Review
Phenylketonuria and Hereditary Tyrosinemia
Phenylalanine hydroxylase (PAH) and fumarylacetoacetate hydroxylase (FAH) are two highly regulated liver enzymes that catalyze the rate-limiting step in phenylalanine and tyrosine metabolism. Mammalian PAH (phenylalanine 4-monooxygenase, E.C. 1.14.16.1) catalyzes the stereospecific hydroxylation of L-phenylalanine into L-tyrosine using tetrahydrobiopterin (BH4), non-heme iron, and dioxygen as co-substrates in the cytosol of the liver and kidney. PAH facilitates oxidation of excess L-phenylalanine into carbon dioxide and water, and is the major enzyme degrading 75% of L-phenylalanine from the diet. PAH assembles as a homotetrameric protein, each subunit composed of N-terminal regulatory domain for allosteric activation by Phe, a central catalytic domain, and C-terminal helix responsible for tetramer formation.
  • 1.7K
  • 27 Oct 2020
Topic Review
MMW Radar in Autonomous Driving
With the rapid development of automated vehicles (AVs), more and more demands are proposed towards environmental perception. Among the commonly used sensors, MMW radar plays an important role due to its low cost, adaptability In different weather, and motion detection capability. Radar can provide different data types to satisfy requirements for various levels of autonomous driving. The objective of this study is to present an overview of the state-of-the-art radar-based technologies applied In AVs. Although several published research papers focus on MMW Radars for intelligent vehicles, no general survey on deep learning applied In radar data for autonomous vehicles exists. Therefore, we try to provide related survey In this paper. First, we introduce models and representations from millimeter-wave (MMW) radar data. Secondly, we present radar-based applications used on AVs. For low-level automated driving, radar data have been widely used In advanced driving-assistance systems (ADAS). For high-level automated driving, radar data is used In object detection, object tracking, motion prediction, and self-localization. Finally, we discuss the remaining challenges and future development direction of related studies.
  • 1.7K
  • 14 Jan 2021
Topic Review
Muse Cells
Muse cells, identified as pluripotent surface marker, stage-specific embryonic antigen (SSEA)-3(+), are endogenous reparative pluripotent stem cells distributed in the bone marrow, peripheral blood and connective tissue of every organ. Since they are non-tumorigenic and do not require gene introduction or cytokine treatment to be rendered pluripotent and induce differentiation, they elicit few safety concerns. They can be delivered intravenously and do not require surgery for their administration since they selectively home to damaged site by sphingosine-1-phosphate (S1P)-S1PR2 axis after intravenous injection. Donor-Muse cells can be used without HLA-matching test or immunosuppressant treatment since they have a specific immunomodulatory system represented by HLA-G expression.
  • 1.7K
  • 12 Oct 2021
Topic Review
Crimean-Congo Hemorrhagic Fever
Crimean-Congo hemorrhagic fever virus (CCHFV) is an arthropod-borne virus (arbovirus), mainly transmitted by ticks, belonging to the genus Orthonairovirus (family Nairoviridae, order Bunyavirales). CCHFV causes a potentially severe, or even fatal, human disease, and it is widely distributed in Africa, Asia, eastern Europe and, more recently, in South-western Europe. Until a few years ago, no cases of Crimean-Congo hemorrhagic fever (CCHF) had been reported in western Europe, with the exception of several travel-associated cases. 
  • 1.7K
  • 10 Jun 2021
Topic Review
Substantia Nigra Imaging in Parkinson
Parkinson’s disease (PD) is a progressive neurodegenerative disorder, characterized by motor and non-motor symptoms due to the degeneration of the pars compacta of the substantia nigra (SNc) with dopaminergic denervation of the striatum. Although the diagnosis of PD is principally based on a clinical assessment, great efforts have been expended over the past two decades to evaluate reliable biomarkers for PD. Among these biomarkers, magnetic resonance imaging (MRI)-based biomarkers may play a key role. Conventional MRI sequences are considered by many in the field to have low sensitivity, while advanced pulse sequences and ultra-high-field MRI techniques have brought many advantages, particularly regarding the study of brainstem and subcortical structures. Nowadays, nigrosome imaging, neuromelanine-sensitive sequences, iron-sensitive sequences, and advanced diffusion weighted imaging techniques afford new insights to the non-invasive study of the SNc. 
  • 1.7K
  • 07 Sep 2023
Topic Review
Nrf2 and Alzheimer’s Disease
Nuclear factor erythroid 2-related factor 2 (Nrf2) is an important transcription factor that reduces oxidative stress. When reactive oxygen species (ROS) or reactive nitrogen species (RNS) are detected, Nrf2 translocates from the cytoplasm into the nucleus and binds to the antioxidant response element (ARE), which regulates the expression of antioxidant and anti-inflammatory genes. Nrf2 impairments are observed in the majority of neurodegenerative disorders, including Alzheimer’s disease (AD). The classic hallmarks of AD include β-amyloid (Aβ) plaques, and neurofibrillary tangles (NFTs). Oxidative stress is observed early in AD and is a novel therapeutic target for the treatment of AD. The nuclear translocation of Nrf2 is impaired in AD compared to controls. Increased oxidative stress is associated with impaired memory and synaptic plasticity. The administration of Nrf2 activators reverses memory and synaptic plasticity impairments in rodent models of AD. Therefore, Nrf2 activators are a potential novel therapeutic for neurodegenerative disorders including AD. 
  • 1.7K
  • 10 Aug 2021
Topic Review
Norm Activation Model and Organic Food Purchase Intention
Attitude plays the most critical role in explaining the organic food purchase intention of Vietnamese consumers, followed by social norms and personal norms. Notably, attitude also remarkably mediated the impact of environmental awareness and knowledge of organic food on purchase intention. Meanwhile, personal norms played the mediating role in the NAM that intervene the connection between social norms and purchase intention. Based on our analysis, we suggested policymakers, manufacturers, marketers, and sellers of organic food change their actions for the growth of the organic food market in Vietnam.
  • 1.7K
  • 19 Apr 2022
Topic Review
Exercise Strategies of Athletes during COVID-19
Elite athletes use high-intensity training to maintain their fitness level. However, intense training can harm the immune system, making athletes suspectable to COVID-19 and negatively affecting their performance. Although high-intensity exercise can suppress the immune system, elite athletes should not stop training in the time of infection but use low- and moderate-intensity training. Moderate-intensity exercise can improve immune function and maintain physical fitness. In addition, it is also better for athletes not to undertake high-intensity training at the time of vaccination, but instead perform moderate to low-intensity training.
  • 1.7K
  • 18 Feb 2022
Topic Review
Objectivism (Ayn Rand)
Objectivism is a philosophical system developed by Russian-American writer Ayn Rand. Rand first expressed Objectivism in her fiction, most notably The Fountainhead (1943) and Atlas Shrugged (1957), and later in non-fiction essays and books. Leonard Peikoff, a professional philosopher and Rand's designated intellectual heir, later gave it a more formal structure. Rand described Objectivism as "the concept of man as a heroic being, with his own happiness as the moral purpose of his life, with productive achievement as his noblest activity, and reason as his only absolute". Peikoff characterizes Objectivism as a "closed system" insofar as its "fundamental principles" were set out by Rand and are not subject to change. However, he stated that "new implications, applications and integrations can always be discovered". Objectivism's main tenets are that reality exists independently of consciousness, that human beings have direct contact with reality through sense perception (see direct and indirect realism), that one can attain objective knowledge from perception through the process of concept formation and inductive logic, that the proper moral purpose of one's life is the pursuit of one's own happiness (see rational egoism), that the only social system consistent with this morality is one that displays full respect for individual rights embodied in laissez-faire capitalism, and that the role of art in human life is to transform humans' metaphysical ideas by selective reproduction of reality into a physical form—a work of art—that one can comprehend and to which one can respond emotionally. Academic philosophers have mostly ignored or rejected Rand's philosophy. Nonetheless, Objectivism has been a significant influence among libertarians and American conservatives. The Objectivist movement, which Rand founded, attempts to spread her ideas to the public and in academic settings.
  • 1.7K
  • 18 Oct 2022
Topic Review
Mammoth Mountain
Mammoth Mountain is a lava dome complex partially located within the town of Mammoth Lakes, California, in the Inyo National Forest of Madera and Mono Counties. It is home to a large ski area primarily on the Mono County side. Mammoth Mountain was formed in a series of eruptions that ended 57,000 years ago. Mammoth still produces hazardous volcanic gases that kill trees and caused ski patroller fatalities in 2006.
  • 1.7K
  • 01 Dec 2022
Topic Review
Fruit and Vegetable Intake and Mental Health in Adults
High total intake of fruits and vegetables, and some of their specific subgroups including berries, citrus, and green leafy vegetables, may promote higher levels of optimism and self-efficacy, as well as reduce the level of psychological distress, ambiguity, and cancer fatalism, and protect against depressive symptoms. The general recommendation to consume at least 5 portions of fruit and vegetables a day may be beneficial also for mental health.
  • 1.7K
  • 30 Oct 2020
Topic Review
Glioblastoma Pathogenesis
Glioblastoma is one of the most common and detrimental forms of solid brain tumor, with over 10,000 new cases reported every year in the United States. Despite aggressive multimodal treatment approaches, the overall survival period is reported to be less than 15 months after diagnosis. A widely used approach for the treatment of glioblastoma is surgical removal of the tumor, followed by radiotherapy and chemotherapy. While there are several drugs available that are approved by the Food and Drug Administration (FDA), significant efforts have been made in recent years to develop new chemotherapeutic agents for the treatment of glioblastoma.
  • 1.7K
  • 28 Dec 2020
Topic Review
Human Immunodeficiency Virus Type 1
Human Immunodeficiency Virus type 1 (HIV-1) is a lentivirus containing two RNA genomes that must be reverse transcribed into double-stranded DNA and then integrated into the host genome to ensure a productive infection. HIV-1 can infect host CD4+ T cells and macrophages, resulting in CD4+ T cell loss and immune dysfunction that leads to the acquired immune deficiency syndrome (AIDS).
  • 1.7K
  • 23 Mar 2021
Topic Review
Plasmin/Plasminogen System in Tumor Microenvironment
Plasmin is an enzyme which is responsible for digesting several proteins that hold the tissues surrounding solid tumors together.
  • 1.7K
  • 23 Jun 2021
Topic Review
Signaling Pathways in Aging
Aging is a fundamental biological process accompanied by a general decline in tissue function. Indeed, as the lifespan increases, age-related dysfunction, such as cognitive impairment or dementia, will become a growing public health issue. 
  • 1.7K
  • 30 Apr 2021
Topic Review
CHD8 and Autism Spectrum Disorder
Autism spectrum disorder (ASD) encompasses a spectrum of early-onset neurodevelopmental disorders with an estimated prevalence of ~1.5% in developed countries. Patients present early deficits in social interaction and communication, repetitive patterns of behavior, and restricted interests and activities.Chromodomain helicase domain 8 (CHD8) is one of the most frequently mutated and most penetrant genes in the autism spectrum disorder (ASD). Individuals with CHD8 mutations show leading symptoms of autism, macrocephaly, and facial dysmorphisms. The molecular and cellular mechanisms underpinning the early onset and development of these symptoms are still poorly understood and prevent timely and more efficient therapies of patients.
  • 1.7K
  • 11 Oct 2021
Topic Review
Biomedical Photonic Sensors
Photonic Sensors (PS) are the set of devices/systems designed to carry out the faithful reproduction of the measurand in the electrical domain using photonic technologies in their key sensor parts.
  • 1.7K
  • 15 Oct 2021
Topic Review Peer Reviewed
The Apicomplexan Parasite Toxoplasma gondii
Toxoplasma gondii  is a ubiquitous zoonotic parasite with an obligatory intracellular lifestyle. It relies on a specialized set of cytoskeletal and secretory organelles for host cell invasion. When infecting its felid definitive host, T. gondii  undergoes sexual reproduction in the intestinal epithelium, producing oocysts that are excreted with the feces and sporulate in the environment. In other hosts and/or tissues, T. gondii  multiplies by asexual reproduction. Rapidly dividing tachyzoites expand through multiple tissues, particularly nervous and muscular tissues, and eventually convert to slowly dividing bradyzoites which produce tissue cysts, structures that evade the immune system and remain infective within the host. Infection normally occurs through ingestion of sporulated oocysts or tissue cysts. While T. gondii  is able to infect virtually all warm-blooded animals, most infections in humans are asymptomatic, with clinical disease occurring most often in immunocompromised hosts or fetuses carried by seronegative mothers that are infected during pregnancy.
  • 1.7K
  • 18 Apr 2022
Topic Review
Platelet Factor 4
Antibodies against platelet factor 4 (PF4), a protein released from alpha-granules of activated platelets, may cause a number of pathophysiological conditions. The most commonly known is heparin-induced thrombocytopenia (HIT), which develops in a small proportion of people treated with the anticoagulant drug heparin.
  • 1.7K
  • 29 Jan 2022
Topic Review
Ferroptosis and Its Role in Chronic Diseases
Ferroptosis, which has been widely associated with many diseases, is an iron-dependent regulated cell death characterized by intracellular lipid peroxide accumulation. It exhibits morphological, biochemical, and genetic characteristics that are unique in comparison to other types of cell death. The course of ferroptosis can be accurately regulated by the metabolism of iron, lipids, amino acids, and various signal pathways. 
  • 1.7K
  • 12 Jul 2022
  • Page
  • of
  • 2799
Featured Entry Collections
>>

Featured Reprints

>>
Encyclopedia of Digital Society, Industry 5.0 and Smart City
Encyclopedia of Engineering
Encyclopedia of Social Sciences
Encyclopedia of Medieval Royal Iconography
Academic Video Service
Feedback