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Topic Review
Autonomous Vehicle Guideline for Public Road-Testing Sustainability
Numerous countries have developed guidelines for public road testing, but those rules are not uniform, and discrepancies occur between nations. Issues such as vehicular safety, registrations, authority, insurance, cybersecurity, and infrastructures weigh differently in each country. Rather than relying on a single national standard as a reference, an amalgam of guidelines from different countries allows a more holistic and measured view of AV testing practices. Synthesizing these diverse national regulations into global guidelines would promote the safety and sustainability of autonomous vehicle testing and benefit all parties interested in autonomous vehicles.
  • 3.1K
  • 17 Feb 2022
Topic Review
Turbulence Simulation Approaches
Turbulent flow can be numerically resolved with different levels of accuracy. Many numerical approaches for solving turbulence have been proposed, such as the Reynolds-Averaged Navier–Stokes (RANS), the Large Eddy Simulation (LES), and Direct Numerical Simulation (DNS) approaches. Among these numerical methods, the RANS approach, specifically the Eddy Viscosity Model (EVM), is widely used for calculating turbulent flows thanks to its relatively high accuracy in predicting the mean flow features and its more limited computational demands. However, this approach suffers from several weaknesses, e.g., compromised accuracy and uncertainties due to assumptions in the model construction and insufficient incorporation of the fluid physics. In the LES approach, the whole eddy range is separated into two parts, namely, the large-scale eddy and subgrid-scale (SGS) eddy. The former can be directly resolved, while the latter is computed using the SGS model. As the computing power rapidly increases, this approach is extensively used to study turbulence physics and to resolve low-to-medium Reynolds number flows.
  • 3.1K
  • 13 Sep 2021
Topic Review
Biomolecular Targeted Covalent Inhibitors
Introduction of artificial structure(s) into a middle-sized therapeutic biomolecule, which would often add a superior function to the drug molecule, is easier than that into an antibody. In this direction, introducing a reactive warhead structure into such therapeutic biomolecules to create BIOmolecular Targeted Covalent Inhibitors (abbreviated as bioTCIs). It would create precise and safe covalent drugs that semi-permanently inhibit the target protein activity upon binding and the duration of the drug effect is only limited by the target protein turnover. Regardless of the modalities, all bioTCIs reduce the skepticism of small-molecule TCIs’ safety concerns because bioTCIs can stringently recognize and conjugate only to the target proteins. Among them, oligonucleotide-type bioTCIs possess unique features, such as nuclease resistance and on-demand-reversal of the drug action with the complementary-strand antidote, which circumvents another major limitation to clinical translation of the aptamer drugs.
  • 3.1K
  • 17 Feb 2023
Topic Review
Tools for Shoreline Change Analysis and Detection
A shoreline is the point of the physical border between land and water. While this definition looks simple, it is indeed challenging in its practical application. The position of the shoreline changes through time due to cross-shore and alongshore sediment movement in the littoral zone, and through changes in water levels. Shoreline change analysis and detection studies have progressed from using simple observation (description) from historical maps and topographical maps to employing high-resolution multi-temporal satellite images with remote sensing and Geographic Information System (GIS) approaches for a better understanding of the subject.
  • 3.1K
  • 05 May 2022
Topic Review
Fuel Cell Hybrid Electric Vehicles
With the development of the global economy, the automobile industry is also developing constantly. In recent years, due to the shortage of environmental energy and other problems, seeking clean energy as the power source of vehicles to replace traditional fossil energy could be one of the measures to reduce environmental pollution. Among them, fuel cell hybrid electric vehicles (FCHEVs) have been widely studied by researchers for their advantages of high energy efficiency, environmental protection, and long driving range.
  • 3.1K
  • 08 Oct 2022
Topic Review
Dyscalculia
Dyscalculia (/ˌdɪskælˈkjuːliə/) is a disability resulting in difficulty learning or comprehending arithmetic, such as difficulty in understanding numbers, learning how to manipulate numbers, performing mathematical calculations and learning facts in mathematics. It is sometimes informally known as "math dyslexia", though this can be misleading as dyslexia is a different condition from dyscalculia. Dyscalculia is associated with dysfunction in the region around the intraparietal sulcus and potentially also the frontal lobe. Dyscalculia does not reflect a general deficit in cognitive abilities or difficulties with time, measurement, and spatial reasoning. Estimates of the prevalence of dyscalculia range between 3 and 6% of the population. In 2015 it was established that 11% of children with dyscalculia also have ADHD. Dyscalculia has also been associated with Turner syndrome and people who have spina bifida. Mathematical disabilities can occur as the result of some types of brain injury, in which case the term acalculia is used instead of dyscalculia which is of innate, genetic or developmental origin.
  • 3.1K
  • 14 Oct 2022
Topic Review
Mechanisms and Classification of Bioactive Peptides
Bioactive peptides have gained significant attention in the cosmetic industry due to their potential in enhancing skin health and beauty. These small protein fragments exhibit various biological activities, such as antioxidant, anti-aging, anti-inflammatory, and antimicrobial activities, making them ideal ingredients for cosmetic formulations. These bioactive peptides are classified into four categories: signal, carrier, neurotransmitter-inhibitory, and enzyme-inhibitory peptides. 
  • 3.1K
  • 18 Aug 2023
Topic Review
GIS Applications
A Geographic Information System (GIS) is a system designed to capture, store, manipulate, analyze, manage, and present spatial or geographic data. GIS applications are tools that allow users to create interactive queries (user-created searches), analyze spatial information, edit data in maps, and present the results of all these operations. GIS (more commonly GIScience) sometimes refers to geographic information science (GIScience), the science underlying geographic concepts, applications, and systems. Since the mid-1980s, geographic information systems have become valuable tool used to support a variety of city and regional planning functions. GIS can refer to a number of different technologies, processes, techniques and methods. It is attached to many operations and has many applications related to engineering, planning, management, transport/logistics, insurance, telecommunications, and business. For that reason, GIS and location intelligence applications can be the foundation for many location-enabled services that rely on analysis and visualization. GIS can relate unrelated information by using location as the key index variable. Locations or extents in the Earth space–time may be recorded as dates/times of occurrence, and x, y, and z coordinates representing, longitude, latitude, and elevation, respectively. All Earth-based spatial–temporal location and extent references should be relatable to one another and ultimately to a "real" physical location or extent. This key characteristic of GIS has begun to open new avenues of scientific inquiry.
  • 3.1K
  • 02 Nov 2022
Topic Review
Helleborus
Commonly known as hellebores (/ˈhɛlɪbɔːrz/), the Eurasian genus Helleborus consists of approximately 20 species of herbaceous or evergreen perennial flowering plants in the family Ranunculaceae, within which it gave its name to the tribe of Helleboreae. Despite names such as "winter rose", "Christmas rose" and "Lenten rose", hellebores are not closely related to the rose family (Rosaceae). Many hellebore species are poisonous.
  • 3.1K
  • 24 Nov 2022
Topic Review
Sand Cat
The Sand Cat (Felis margarita) is a small wild cat species adapted to desert environments across North Africa, the Middle East, and Central Asia. Renowned for its remarkable ability to thrive in extreme desert conditions, the Sand Cat possesses unique adaptations such as large ears, dense fur, and specialized paw pads to navigate sandy terrain and regulate body temperature. Despite its elusive nature, the Sand Cat plays a crucial role in desert ecosystems as a predator of small rodents and reptiles, contributing to the balance of prey populations and ecosystem dynamics in arid regions.
  • 3.1K
  • 08 Mar 2024
Topic Review
Flake Powder Metallurgy
Flake powder metallurgy (FPM) including different processing routes, conventional FPM (C-FPM), slurry blending (SB), shift-speed ball milling (SSBM), and high-shear pre-dispersion and SSBM (HSPD/SSBM). The name of FPM was derived from the use of flake metal powders obtained by low-speed ball milling (LSBM) from spherical powder. The uniformity of reinforcement distribution leads to increased strength and ductility. Powder is the basic unit in PM, especially advanced PM, and its control is key to various new PM technologies. The FPM is a typical method for finely controlling the powder shape through low-energy ball milling (LEBM) to realize the preparation of advanced material structures. 
  • 3.1K
  • 23 Jun 2021
Topic Review
Agricultural Activities in the Lake Chad Region
Lake Chad is a strategic water resource shared by more than 40 million people in Sub-Saharan Africa. In the 1960s, it served as a primary source of water for irrigation and fishing in the region, but the capacity of Lake Chad to supply water for irrigation plummeted by 90% at the beginning of the twenty-first century. With some initiatives taken by the neighboring countries, Lake Chad has recovered about 5% of its water volume in recent years.
  • 3.1K
  • 18 Jul 2023
Topic Review
Flash-Boiling Atomization
Flash-boiling atomization is a method by which a liquid is brought into a superheated state, such as vigorous boiling, in a short timeframe while the bubbles grow considerably fast. This leads to the disintegration of the continuous liquid into tiny droplets. Flash-boiling, effervescent, and air-assisted atomization are based on a two-phase flow to achieve effective atomization. 
  • 3.1K
  • 07 Oct 2023
Topic Review
Chelating Agents in Soil Remediation
The Fenton process is an efficient treatment for removing many organics pollutants in aqueous systems at acidic pH (2.8-3.5). However, the in-situ application of this technology for soil remediation (where pHs around neutrality are required) presents important limitations, such as catalyst (iron) availability and oxidant (H2O2) stability. The addition of chelating agents (CAs) makes iron soluble at circumneutral pH by forming complexes with Fe, and thus, enabling Fenton reactions under these conditions. This strategy, called chelate-modified Fenton process (MF), can be employed to overcome the challenges identified in conventional Fenton.
  • 3.1K
  • 09 Aug 2021
Topic Review
Addressing, Assessing and Improving Water Security
Water security is about managing too much, too little and/or too polluted water. Water security is about the increasing importance of sustainable management of water resources, drinking water and human well-being and protection of life and property from water-related disasters. Water security is about the health of ecosystems and economic development.  A groundwork of this broad and multi-faceted concept is presented to facilitate understanding, measuring and improving water security. 
  • 3.1K
  • 25 Jan 2022
Topic Review
LiveJournal
LiveJournal (Russian: Живой Журнал), stylised as LiVEJOURNAL, is a Russian social networking service where users can keep a blog, journal or diary. American programmer Brad Fitzpatrick started LiveJournal on April 15, 1999, as a way of keeping his high school friends updated on his activities. In January 2005, American blogging software company Six Apart purchased Danga Interactive, the company that operated LiveJournal, from Fitzpatrick. Six Apart sold LiveJournal to Russian media company SUP Media in 2007; the service continued to operate out of the U.S. via a California-based subsidiary, LiveJournal, Inc., but began moving some operations to Russian offices in 2009. In December 2016, the service relocated its servers to Russia, and in April 2017, LiveJournal changed its terms of service to conform to Russian law. As with other social networks, a wide variety of public figures use the service, as do political pundits, who use it for political commentary, particularly in Russia, where it partners with the online newspaper Gazeta.ru.
  • 3.1K
  • 08 Oct 2022
Topic Review
Galileo Probe
The Galileo Probe was an atmospheric-entry probe carried by the main Galileo spacecraft to Jupiter, where it directly entered a hot spot and returned data from the planet. The 339-kilogram (747 lb) probe was built by Hughes Aircraft Company at its El Segundo, California plant, and measured about 1.3 meters (4.3 ft) across. Inside the probe's heat shield, the scientific instruments were protected from extreme heat and pressure during its high-speed journey into the Jovian atmosphere, entering at 47.8 kilometers (29.7 mi) per second. It entered Jupiter on December 7, 1995, 22:04 UTC and stopped functioning at 23:01 UTC, 57 minutes and 36 seconds later.
  • 3.1K
  • 17 Oct 2022
Topic Review
Pi Interaction
In chemistry, π-effects or π-interactions are a type of non-covalent interaction that involves π systems. Just like in an electrostatic interaction where a region of negative charge interacts with a positive charge, the electron-rich π system can interact with a metal (cationic or neutral), an anion, another molecule and even another π system. Non-covalent interactions involving π systems are pivotal to biological events such as protein-ligand recognition.
  • 3.1K
  • 07 Dec 2022
Topic Review
Prevention and Control Strategies for Maize White Spot
Maize white spot (MWS), caused by the bacterium Pantoea ananatis, is a serious disease that significantly impacts maize production and productivity. Researchers from various countries worldwide have conducted extensive research on this pathogen, including its isolation and identification, the localization of resistance genes, transmission pathways, as well as potential control measures.
  • 3.1K
  • 15 Nov 2023
Topic Review
Synthesis of β-Lactams
Stereoselective synthesis of cis and trans β-lactams under diverse conditions is performed.  Numerous conditions are used for this study. The formation of β-lactam depends on the conditions of the experiments, structures of the imines and acid chlorides, order of addition of the reagents, reaction temperature, and solvents. A few mathematical graphs are plotted to explain the results.   
  • 3.1K
  • 25 Nov 2020
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