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Topic Review
Runaway Climate Change
Runaway climate change or runaway global warming is hypothesized to follow a tipping point in the climate system, after accumulated climate change initiates a reinforcing positive feedback. This rapid acceleration in climate change may lead to potentially irreversible damage to the climate system, making timely mitigation efforts unfeasible. This is thought to cause the climate to rapidly change until it reaches a new stable condition. These phrases may be used with reference to concerns about rapid global warming. Some astronomers use the expression runaway greenhouse effect to describe a situation where the climate deviates catastrophically and permanently from the original state—as happened on Venus. Although these terms are rarely used in the peer-reviewed climatological literature, that literature does use the similar phrase "runaway greenhouse effect", which refers specifically to climate changes that cause a planetary body's water to boil off.
  • 3.8K
  • 01 Nov 2022
Topic Review
Bengal Tiger
The Bengal Tiger (Panthera tigris tigris) stands as one of the most majestic and iconic big cat species, native to the Indian subcontinent. Renowned for its striking orange coat adorned with characteristic black stripes, the Bengal Tiger commands reverence and admiration as the largest tiger subspecies. As a symbol of strength and beauty, the Bengal Tiger plays a vital role in both cultural heritage and conservation efforts aimed at protecting its dwindling populations and vanishing habitats.
  • 3.8K
  • 28 Feb 2024
Topic Review
The Bruun Rule
The Bruun Rule is a formula for estimating the magnitude of the retreat of the shoreline of a sandy shore in response to changes in sea level. Originally published in 1962 by Per Bruun, the Bruun Rule was the first to give a relationship between sea level rise and shoreline recession. The rule is a simple, two dimensional mass conversion, and remains in common use to estimate shoreline recession in response to sea level rise, despite criticism and modification, and the availability more complex alternate models.
  • 3.8K
  • 28 Oct 2022
Topic Review
Aerial Photography
Aerial photography (or airborne imagery) is the taking of photographs from an aircraft or other flying object. Platforms for aerial photography include fixed-wing aircraft, helicopters, unmanned aerial vehicles (UAVs or "drones"), balloons, blimps and dirigibles, rockets, pigeons, kites, parachutes, stand-alone telescoping and vehicle-mounted poles. Mounted cameras may be triggered remotely or automatically; hand-held photographs may be taken by a photographer. Aerial photography should not be confused with air-to-air photography, where one or more aircraft are used as chase planes that "chase" and photograph other aircraft in flight.
  • 3.8K
  • 30 Nov 2022
Topic Review
Surface-Functionalized Nanoparticles for Bio-Application
Surface functionalization of nanoparticles applies to the use of covalent and non-covalent bonds—such as hydrogen bonds, electrostatic force, and the van der Waals interactions—to integrate diverse organic and inorganic molecules at the nanoscale. Typically, multiple linker molecules are used to form covalent bonds between ligands and the surfaces of nanoparticles (NPs).
  • 3.8K
  • 20 Apr 2022
Topic Review
Collagen in Wound Healing
Collagens are the most abundant protein found throughout the body. In the healing wound, these collagens are synthesized by cells such as fibroblasts and modified into complex morphologies . The type, amount and organization of collagen changes in the healing wound and determines the tensile strength of the healed skin. Collagen III is the first to be synthesized in the early stages of wound healing and is replaced by collagen I, the dominant skin collagen. The initial random deposition of collagen during the granulation tissue formation is further enhanced by lysyl oxidase enzyme-induced covalent cross-linking. This process matures the collagen into complex structures that are reoriented for tensile strength restoration. Collagen remodeling continues for months after wound closure and the tensile strength of the repaired tissue increases to about 80–85% of normal tissue if all processes proceed without any perturbations.In the skin, the fibrillar collagens types I, III and V are the most common, followed by fibril-associated collagens type XII, XIV, XVI, and VI. The non-fibrillar collagens type IV, XVIII are found in the basement membrane of the skin
  • 3.8K
  • 23 Jun 2021
Topic Review
Adenosine Deaminase
Adenosine deaminase (ADA, EC 3.5.4.4) - the enzyme engaged in purine metabolism that irreversibly converts adenosine or 2′deoxyadenosine to inosine or 2′deoxyinosine, respectively. In human tissues, it occurs as two isoenzymes: ADA1 and ADA2. ADA1 constitutes the majority of ADA activity and it is present in virtually all tissues, while ADA2 has been found with ADA1 only in monocytes/macrophages. Both ADA isoenzymes are present in cytosolic form, soluble fraction that can be located away from the originating cell, or as ecto-enzymes binding to the cell surface by dedicated proteins. Intracellularly, ADA plays a significant role counteracting high concentrations of 2'deoxyadenosine. When intracellular ADA activity is lowered, e.g. during severe combined immunodeficiency disease (SCID), 2′deoxyadenosine accumulates and is converted to 2′-deoxyadenosine-5′-triphosphate (dATP), which inhibits ribonucleotide reductase (RNR), a crucial enzyme in DNA synthesis that follows disrupted T-cell development. Intracellular concentration of adenosine, the second substrate for ADA, is maintained inside the cell on the low level by adenosine kinase with Km value ~ 1 µM. Under conditions of low energy charge, adenosine-5′-monophosphate (AMP) that originates from adenosine-5′-triphosphate (ATP) degradation, is rapidly transformed to adenosine, which is not immediately deaminated to inosine due to high Km of ADA (25–100 µM). This results in temporary accumulation of adenosine that is vigorously exported out the cell via equilibrative nucleoside transporters (ENTs). Therefore, transmembrane adenosine transport, together with the activities of ecto-ADA and soluble ADA are important regulators of extracellular adenosine concentration. Except enzymatic function, ecto-ADA plays a significant extra-enzymatic role in the interactions between cells that expressed ADA-anchoring proteins on their surfaces. This co-stimulatory and cell-to-cell connecting actions along with its activity regulate many cellular processes related to proliferation and differentiation, which affect pathological conditions associated with cardiovascular diseases such as endothelial activation and dysfunction, inflammation, myocardial ischemia-reperfusion injury, or coagulation disorders. Since these pathologies are associated with ADA overexpression, the inhibition of its activity as well as binding to the surface proteins exhibit an attractive therapeutic potential in cardiovascular diseases.
  • 3.8K
  • 30 Oct 2020
Topic Review
European Hedgehog (Erinaceus Europaeus): Sentinel
Erinaceus europaeus is a cosmopolitan mammalian species broadly distributed in Europe, from natural to suburban areas. Due to its ecological role and susceptibility to distinct zoonotic agents, E. europaeus could be a suitable sentinel candidate for many global problems that negatively affect human and animal health. Hedgehogs can work as bioindicators to environmental contamination and can be hosts for multiple tickborne zoonotic agents. 
  • 3.8K
  • 04 Jul 2022
Topic Review
Laser-Induced Breakdown Spectroscopy
Laser-Induced Breakdown Spectroscopy (LIBS) has been firstly introduced and proposed for analytical applications almost immediately after the invention of the laser in 1960. Since then, it has been proposed and today is widely used as an alternative analytical method for numerous applications. The operating principle of LIBS is quite simple and is based on the interaction of a powerful enough laser beam, focused usually on or in a sample, inducing a dielectric breakdown of the material, thus resulting in plasma formation consisting of excited and non-excited atoms and molecules, fragments of molecular species, electrons and ions, and emitting characteristic radiations, whose spectroscopic analysis can in principle provide the elemental composition fingerprint of the material. The required instrumentation consisting basically of a laser source, and a spectrometer/monochromator equipped with the appropriate light detector (nowadays being almost exclusively some CCD or ICCD type detector) is relatively simple and economically affordable, while significant progresses have been achieved to small size and/or portable equipment, facilitating largely the in situ operation.
  • 3.8K
  • 31 Aug 2021
Topic Review
Urban Horticulture for Food Security
Sufficient production, consistent food supply, and environmental protection in urban +settings are major global concerns for future sustainable cities. Currently, sustainable food supply is under intense pressure due to exponential population growth, expanding urban dwellings, climate change, and limited natural resources. The recent novel coronavirus 2019 (COVID-19) pandemic crisis has impacted sustainable fresh food supply and has disrupted the food supply chain and prices significantly. Under these circumstances, urban horticulture and crop cultivation have emerged as potential ways to expand to new locations through urban green infrastructure. Therefore, the objective of this study is to review the salient features of contemporary urban horticulture, in addition to illustrating traditional and innovative developments occurring in urban environments. Current urban cropping systems, such as home gardening, community gardens, edible landscape, and indoor planting systems, can be enhanced with new techniques, such as vertical gardening, hydroponics, aeroponics, aquaponics, and rooftop gardening. These modern techniques are eco-friendly, energy-saving, and promise food security through steady supplies of fresh fruits and vegetables to urban neighborhoods. There is a need, in this modern era, to integrate information technology tools in urban horticulture, which could help in maintaining consistent food supply during (and after) a pandemic, as well as make agriculture more sustainable.
  • 3.8K
  • 04 Dec 2020
Topic Review
The Swampland Distance Conjecture
The Swampland Distance Conjecture (SDC) is one of the most studied and well-established Swampland Conjetures, and it introduces an omnipresent feature in effective field theories (EFTs) of quantum gravity, namely the appearance of infinite towers of states that become light an imply a breakdown of the EFT in the infinite distance limits in moduli space. In this entry we present the conjecture, a simple example and some comments on relations to other conjectures.
  • 3.8K
  • 18 Aug 2021
Topic Review Peer Reviewed
Asexual Epichloë Fungi—Obligate Mutualists
Asexual Epichloë are obligate fungal mutualists that form symbiosis with many temperate grass species, providing several advantages to the host. These advantages include protection against vertebrate and invertebrate herbivores (i.e., grazing livestock and invertebrate pests, respectively), improved resistance to phytopathogens, increased adaptation to drought stress, nutrient deficiency, and heavy metal-containing soils. Selected Epichloë strains are utilised in agriculture mainly for their pest resistance traits, which are moderated via the production of Epichloë-derived secondary metabolites. For pastoral agriculture, the use of these endophyte infected grasses requires the balancing of protection against insect pests with reduced impacts on animal health and welfare.
  • 3.8K
  • 13 Apr 2022
Topic Review
Windows 10 Version History (Version 1809)
The Windows 10 October 2018 Update (also known as version 1809 and codenamed "Redstone 5") is the sixth major update to Windows 10 and the fifth in a series of updates under the Redstone codenames. It carries the build number 10.0.17763.
  • 3.8K
  • 08 Nov 2022
Topic Review
Radar-Based Drone Detection Technologies
The fast development of unmanned aerial vehicles (UAVs), commonly known as drones, has brought a unique set of opportunities and challenges to both the civilian and military sectors. While drones have proven useful in sectors such as delivery, agriculture, and surveillance, their potential for abuse in illegal airspace invasions, privacy breaches, and security risks has increased the demand for improved detection and classification systems. Principles of radar-based detection: Radar, which stands for “Radio Detection and Ranging”, is generally considered one of the most trustworthy sensing devices that comes to mind when addressing UAV detection since it has traditionally been utilized for aircraft detection in both military and civilian purposes (such as aviation). Radar is an electromagnetic technology that employs radio waves to detect and locate nearby objects. Any radar system works on the basis of echo-based measurements and consists of a radar transmitter that sends out short electromagnetic waves in the radio or microwave band, transmitting and receiving antennas, a radar receiver that receives the reflected signals from the target, and a processor that identifies the objects’ attributes. Therefore, radar can calculate important object characteristics, including distance, velocity, azimuth, and elevation.
  • 3.8K
  • 04 Jan 2024
Topic Review
Capybara (Hydrochoerus hydrochaeris)
The capybara (Hydrochoerus hydrochaeris) is a large, semi-aquatic mammal native to South America, recognized for its sociable behavior, robust physical form, and distinctive appearance. As the largest living rodent species, the capybara typically inhabits wetlands, riverbanks, and grasslands throughout the continent, ranging from Colombia and Venezuela to Argentina and Uruguay. It plays a significant ecological role in its native habitat and is closely associated with freshwater environments due to its need for access to water for survival and feeding. The capybara has garnered attention in recent years due to its distinctive social structure and behaviors, as well as its relatively calm disposition when interacting with humans and other species.
  • 3.8K
  • 08 Jul 2025
Topic Review
Choleretic and Cholagogic Effects of Anticholelithiatic Plants
A large number of people suffer from gall stone worldwide and this problem is now being increased significantly due to the malnutrition, changes in living style, lack of exercise and conditions i.e. industrialization. Medicinal plants are used from centuries due to their cultural acceptability, efficacy, safety and fewer side effects as compared to modern synthetic medicines.
  • 3.7K
  • 15 Aug 2022
Topic Review
Types of Pipeline Anomalies
Pipelines are considered the most efficient way to transport oil and gas resources. However, this advantage of pipelines may be lost if pipeline integrity is not ensured. Geometric deformations, metal losses, and crack-type anomalies caused by various reasons in the pipeline threaten the integrity of the pipeline. Therefore, it is important to examine the causes of occurrence, hazard potentials, and management methods of pipeline anomalies as part of pipeline integrity management. 
  • 3.7K
  • 27 Apr 2023
Topic Review
Secure Shell Protocol
The Secure Shell Protocol (SSH) is a cryptographic network protocol for operating network services securely over an unsecured network. Typical applications include remote command-line, login, and remote command execution, but any network service can be secured with SSH. SSH provides a secure channel over an unsecured network by using a client–server architecture, connecting an SSH client application with an SSH server. The protocol specification distinguishes between two major versions, referred to as SSH-1 and SSH-2. The standard TCP port for SSH is 22. SSH is generally used to access Unix-like operating systems, but it can also be used on Microsoft Windows. Windows 10 uses OpenSSH as its default SSH client and SSH server. SSH was designed as a replacement for Telnet and for unsecured remote shell protocols such as the Berkeley rsh and the related rlogin and rexec protocols. Those protocols send information, notably passwords, in plaintext, rendering them susceptible to interception and disclosure using packet analysis. The encryption used by SSH is intended to provide confidentiality and integrity of data over an unsecured network, such as the Internet.
  • 3.7K
  • 29 Sep 2022
Topic Review
Climate Change Education in Finland
The climate change education (CCE) is understood as a component of environmental education and education for sustainable development. Its core concept is CC literacy, which means that students understand the scientific concepts related to CC and the relationships between them, as well as the effects of CC and their own activities on the environment. CCE is multidisciplinary and interdisciplinary. Multidisciplinarity means that knowledge of various individual sciences is needed. Interdisciplinarity, on the other hand, incorporates elements from a variety of disciplines and also integrates environmental, economic, social and political issues.
  • 3.7K
  • 30 Mar 2022
Topic Review
Grid-Forming Converters and Power System Stability
Historically, the power system has relied on synchronous generators (SGs) to provide inertia and maintain grid stability. However, because of the increased integration of power-electronics-interfaced renewable energy sources, the grid’s stability has been challenged in the last decade due to a lack of inertia. Currently, the system predominantly uses grid-following (GFL) converters, built on the assumption that inertial sources regulate the system stability. Such an assumption does not hold for the low-inertia grids of the future. Grid-forming (GFM) converters, which mimic the traditional synchronous machinery’s functionalities, have been identified as a potential solution to support the low-inertia grids. The performance analysis of GFM converters for small-signal instability can be found in the literature, but large-signal instability is still an open research question. Moreover, various topologies and configurations of GFM converters have been proposed. Still, no comparative study combining all GFC configurations from the perspective of large-signal stability issues can be found. This research combines and compares all the existing GFM control schemes from the perspective of large-signal stability issues to pave the way for future research and development of GFM converters for large-signal stability analysis and stabilization of the future low-inertia grids. 
  • 3.7K
  • 19 Jul 2022
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