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Topic Review
Uncontrolled Chronic Rhinosinusitis with Nasal Polyps
Chronic rhinosinusitis (CRS) is recognized as a heterogeneous disease with a wide range of clinical features, resulting in significant morbidity and cost to the healthcare system. The phenotypic classification is determined by the presence or absence of nasal polyps and comorbidities, the endotype classification has been established based on molecular biomarkers or specific mechanisms.
  • 321
  • 09 Jun 2023
Topic Review
Uncontrolled and Controlled Destruction of Acetylene Pressure Cylinders
The risk of physical destruction of a pressure cylinder increases with increasing temperature load. Acetylene is a significant hazardous gas in cylinders. If the destruction pressure is reached, the cylinder is torn into two or more pieces, followed by the gas release to the environment. The presence of ignition sources could lead to the formation of the fireball phenomenon. This phenomenon generally reaches approximately ten meters in diameter and can be accompanied by a blast wave and a spread of the cylinder’s fragments or surrounding objects. The consequences of this type of fire could be fatal. Shooting through the cylinder shell may lead to the mitigation, if not elimination, of the effects of the uncontrolled destruction mentioned above. As a result of the review of relevant publications, several states commonly use this method as a standard procedure. Internal gas is released through the resulting hole, the pressure drops down and the gas creates a fire jet or disperses to surroundings. This study is based on a large-scale experiment where acetylene cylinders were placed inside a prepared woodpile and exposed to fire. In the fire condition, the cylinders exploded and created fireballs, or were penetrated via shooting and created fire jets.
  • 505
  • 27 May 2022
Topic Review
Uncompetitive Inhibitor
Uncompetitive inhibition, also known as anti-competitive inhibition, takes place when an enzyme inhibitor binds only to the complex formed between the enzyme and the substrate (the E-S complex). Uncompetitive inhibition typically occurs in reactions with two or more substrates or products. While uncompetitive inhibition requires that an enzyme-substrate complex must be formed, non-competitive inhibition can occur with or without the substrate present. Uncompetitive inhibition is distinguished from competitive inhibition by two observations: first uncompetitive inhibition cannot be reversed by increasing [S] and second, as shown, the Lineweaver–Burk plot yields parallel rather than intersecting lines. This behavior is found in the inhibition of acetylcholinesterase by tertiary amines (R3N). Such compounds bind to the enzyme in its various forms, but the acyl-intermediate-amine complex cannot break down into enzyme plus product.
  • 18.5K
  • 16 Nov 2022
Topic Review
Uncombable Hair Syndrome
Uncombable hair syndrome is a condition that is characterized by dry, frizzy hair that cannot be combed flat. 
  • 520
  • 23 Dec 2020
Topic Review
Uncertainty Modelling for Probabilistic Power System Stability Analysis
The increased penetration of system uncertainties related to renewable energy sources, new types of loads and their fluctuations, and deregulation of the electricity markets necessitates probabilistic power system analysis. The abovementioned factors significantly affect the power system stability, which requires computationally intensive simulation, including frequency, voltage, transient, and small disturbance stability. Altogether 40 uncertainty modelling (UM) techniques are collated with their characteristics, advantages, disadvantages, and application areas, particularly highlighting their accuracy and efficiency (as both are crucial for power system stability applications). 
  • 401
  • 17 Jan 2023
Topic Review
Uncertain Travel Times in Distribution Logistics
Uncertainty quantification is a critical aspect of distribution logistics, particularly unpredictable travel times caused by traffic congestion and varying transportation conditions.
  • 283
  • 17 Nov 2023
Topic Review
Uncaria rhynchophylla and Alzheimer’s Disease
Alzheimer’s disease (AD) is a growing concern in modern society, and effective drugs for its treatment are lacking. Uncaria rhynchophylla (UR) and its main alkaloids have been studied to treat neurodegenerative diseases such as AD. This study aimed to uncover the key components and mechanism of the anti-AD effect of UR alkaloids through a network pharmacology approach.
  • 825
  • 06 Apr 2021
Topic Review
UNC80 Deficiency
UNC80 deficiency is a severe disorder characterized by nervous system and developmental problems that are apparent from birth or early infancy. The disorder does not typically get worse over time; development of intellectual function and motor skills, such as rolling over and sitting, is slow and limited, but once skills are learned, they are usually retained.  
  • 581
  • 23 Dec 2020
Topic Review
Unc-51-like Autophagy-Activating Kinase Inhibitors as Anticancer Agents
Autophagy is a cellular process that removes damaged components of cells and recycles them as biochemical building blocks. Autophagy can also be induced to protect cells in response to intra- and extracellular stresses, including damage to cellular components, nutrient deprivation, hypoxia, and pathogenic invasion. Dysregulation of autophagy has been attributed to various diseases. In particular, autophagy protects cancer cells by supporting tumor cell survival and the development of drug resistance. The ULK complex is an early-stage regulator of autophagy and attracted particular attention as a drug target. Among ULK isoforms, ULK1, ULK2, ULK3, ULK4, and serine/threonine-protein kinase 36 (STK36), ULK1 have been most extensively studied.
  • 643
  • 20 Jan 2023
Topic Review
UNC
UNC is a set of proteins first identified through a set of screening tests in Caenorhabditis elegans, looking for roundworms with movement problems. Worms with which were un-coordinated (hence UNC) were analysed in order to identify the genetic defect. Such proteins include UNC-5, a receptor for UNC-6 which is one of the netrins. Netrins are a class of proteins involved in axon guidance. UNC-5 uses repulsion (genetics) to direct axons while the other netrin receptor UNC-40 attracts axons to the source of netrin production.
  • 243
  • 18 Oct 2022
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