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Topic Review
Arba'een
Template:HusaynTemplate:Islamic Culture Arba'ein (Arabic: الأربعين), Chehellom (Persian: چهلم‎, "the fortieth day") is a Shia religious observance that occurs forty days after the Day of Ashura. It commemorates the martyrdom of Al-Husayn ibn Ali, the grandson of Muhammad, who was martyred on the 10th day of the month of Muharram.Imam Hussain ibn Ali and 71 of his companions were martyred by Ubayd Allah ibn Ziyad's army under the governance of Yazeed Malhoon in the Battle of Karbala in 61 AH (680 CE). Arba'ein or forty days is also the usual length of mourning after the death of a family member or loved one in many Muslim traditions. Arba'ein is the largest annual pilgrimage in the world, in which up to 40 million (In reality, there are no reliable methods for tallying the number of site visitors. This is an entirely estimated set of statistics. Logically, it is possible to gather 40m persons on a small city) people go to the city of Karbala in Iraq.
  • 3.8K
  • 07 Nov 2022
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
Timeline of Malaria
Malaria is an infectious disease caused by a parasite; it is spread by the bite of an infected mosquito. Every year, 300 to 700 million people get infected. Malaria kills 1 million to 2 million people every year. 90% of the deaths occur in Africa.
  • 3.8K
  • 31 Oct 2022
Topic Review
Duckweeds for Remediating Water Contaminated with Heavy Metals
Tiny aquatic plants from the Lemnaceae family, commonly known as duckweeds, are often regarded as detrimental to the environment because of their ability to quickly populate and cover the surfaces of bodies of water. The global distribution of duckweeds and their tolerance of ammonia, heavy metals, other pollutants, and stresses are the major factors highlighting their potential for use in purifying agricultural, municipal, and some industrial wastewater. In summary, duckweeds are a powerful tool for bioremediation that can reduce anthropogenic pollution in aquatic ecosystems and prevent water eutrophication in a simple, inexpensive ecologically friendly way.
  • 3.8K
  • 09 May 2023
Topic Review
Photocatalytic Properties of SnO2
SnO2 is an n-type semiconductor with a band gap between 3.6 and 4.0 eV, whose intrinsic characteristics are responsible for its electrical conductivity, good optical characteristics, high thermal stability, and other qualities. Such characteristics have provided excellent results in advanced oxidative processes, i.e., heterogeneous photocatalysis applications. This process involves semiconductors in the production of hydroxyl radicals via activation by light absorption, and it is considered as an emerging and promising technology for domestic-industrial wastewater treatment.
  • 3.8K
  • 05 May 2022
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
Kaleidoscope
A kaleidoscope (/kəˈlaɪdəskoʊp/) is an optical instrument with two or more reflecting surfaces (or mirrors) tilted to each other at an angle, so that one or more (parts of) objects on one end of the mirrors are seen as a regular symmetrical pattern when viewed from the other end, due to repeated reflection. The reflectors are usually enclosed in a tube, often containing on one end a cell with loose, colored pieces of glass or other transparent (and/or opaque) materials to be reflected into the viewed pattern. Rotation of the cell causes motion of the materials, resulting in an ever-changing view being presented.
  • 3.8K
  • 04 Nov 2022
Topic Review
Water radical cations
The study of water continues to provide surprises as evidenced by recent work on the surfaces of small droplets. Systems comprising numbers of water molecules and corresponding cations represent a topic of special interest, such as nuclear safety, functional biomolecules (DNA, RNA, and proteins) damage, proton transfer process and so on. To date, water radical cations have been created through wet nitrogen ionized as a result of subjected to electron-impact ionization, photoionization of a water molecular beam or vapor, even including in helium nanodroplets. They have also been generated through intermolecular coulomb decay process by high-energy photos or above 70 eV electrons impactions.For (H2O)2+•, a theoretical simulation led to both the structure resulting from proton transfer and the dimer cation structure. For larger water radical cations, these clusters are easily constructed from the (H2O)nH+ structures by substituting one of the water molecules, which is the next neighbor of the charged site for •OH radical. Besides the ultra-fast proton transfer reaction within (H2O)n+• , and between (H2O)n+• and its neighboring water molecules to form the proton transfer product, (H2O)n+• also present ultrafast charge migration from a solute M to (H2O)n+•.
  • 3.8K
  • 27 Oct 2020
Topic Review
PEC Reactors for Water/Wastewater Treatment
Now and in the coming years, how we use and treat water, greywater and wastewater will become more important. A suitably designed photoelectrocatalytic (PEC) reactor is one potential solution. The photoexcitation of suitable semiconducting materials in aqueous environments can lead to the production of reactive oxygen species (ROS). ROS can inactivate microorganisms and degrade a range of chemical compounds. In the case of heterogeneous photocatalysis, semiconducting materials may suffer from fast recombination of electron–hole pairs and require post-treatment to separate the photocatalyst when a suspension system is used. To reduce recombination and improve the rate of degradation, an externally applied electrical bias can be used where the semiconducting material is immobilised onto an electrically conducive support and connected to a counter electrode. These electrochemically assisted photocatalytic systems have been termed “photoelectrocatalytic” (PEC). The term is stated in the IUPAC Recommendations 2011 as “electrochemically assisted photocatalysis. The role of the photocatalyst is played by a photoelectrode, often a semiconductor”. A short description of photocatalysis is included as it can be beneficial for those unfamiliar with the topic, before moving onto PEC. This entry is adapted from https://doi.org/10.3390/w13091198
  • 3.8K
  • 20 Oct 2021
Topic Review
Biological Half-life
The biological half-life of a biological substance is the time it takes for half to be removed by biological processes. This concept is used when the rate of removal is roughly exponential. It is often denoted by the abbreviation [math]\displaystyle{ t_{\frac{1}{2}} }[/math]. This is used to measure the removal of things such as metabolites, drugs, and signalling molecules from the body. Typically, the biological half-life refers to the body's natural cleansing through the function of the liver and through the excretion of the measured substance through the kidneys and intestines. In a medical context, half-life explicitly describes the time it takes for the blood plasma concentration of a substance to halve (plasma half-life) its steady-state when circulating in the full blood of an organism. This measurement is useful in medicine and pharmacology because it helps determine how much of a drug needs to be taken and how frequently it needs to be taken if a certain average amount is needed constantly. In contrast, the stability of a substance direct in plasma is described with plasma stability that is essential to ensure accurate analysis of drugs in plasma and for Drug discovery. The relationship between the biological and plasma half-lives of a substance can be complex depending on the substance in question, due to factors including accumulation in tissues (protein binding), active metabolites, and receptor interactions.
  • 3.8K
  • 17 Nov 2022
Topic Review
LncRNA Mechanisms of Action
Long non-coding (lnc)RNAs have emerged as critical regulators of gene expression and are involved in almost every cellular process. They can bind to other molecules including DNA, proteins, or even other RNA types such messenger RNA or small RNAs. LncRNAs are typically expressed at much lower levels than mRNA, and their expression is often restricted to tissue- or time-specific developmental stages. They are also involved in several inter-species interactions, including vector–host–pathogen interactions, where they can be either vector/host-derived or encoded by pathogens. In these interactions, they function via multiple mechanisms including regulating pathogen growth and replication or via cell-autonomous antimicrobial defense mechanisms. Recent advances suggest that characterizing lncRNAs and their targets in different species may hold the key to understanding the role of this class of non-coding RNA in interspecies crosstalk. 
  • 3.8K
  • 07 Feb 2021
Topic Review
Neuron Migration
Radial neuron migration in the developing cerebral cortex is a complex journey, starting in the germinal zones and ending in the cortical plate. In mice, migratory distances can reach several hundreds of microns, or millimeters in humans. Along the migratory path, radially migrating neurons slither through cellularly dense and complex territories before they reach their final destination in the cortical plate.
  • 3.8K
  • 06 Jan 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
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.
  • 3.8K
  • 29 Sep 2022
Topic Review
Interpersonal Relationship
Interpersonal relationships refer to the social connections and interactions between individuals, characterized by emotional bonds, communication, and mutual influence. These relationships encompass various forms, including friendships, familial ties, romantic partnerships, and professional connections, playing a crucial role in shaping individuals' social and emotional well-being.
  • 3.8K
  • 25 Jan 2024
Topic Review
Agri-Food Waste
Agri-Food Waste (AFW) originates throughout the whole food supply chain, from production to post-harvesting, industrial processing, distribution, domestic processing, and consumption, with wastage volumes differing among phases and food commodities. Conventional management of food waste encompasses production of renewable energy, animal feeds, and compost. Alternative pathways include the valorization of food waste as a source of bioactive compounds, such as phenolic compounds, to be used as functional food ingredients or nutraceuticals. Drying and size reduction techniques, extraction methods, and fermentation are the main strategies to turn AFW into functional ingredients.
  • 3.8K
  • 18 Dec 2020
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
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
Citrulline and Quercetin on Gut Microbiota
The importance of gut health in animal welfare and wellbeing is undisputable. The intestinal microbiota plays an essential role in the metabolic, nutritional, physiological, and immunological processes of animals. Therefore, the rapid development of dietary supplements to improve gut functions and homeostasis is imminent. 
  • 3.8K
  • 15 Nov 2021
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.
  • 3.8K
  • 30 Mar 2022
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