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Topic Review
Reversible Hydrogen Storage
In the field of energy storage, recently investigated nanocomposites show promise in terms of high hydrogen uptake and release with enhancement in the reaction kinetics. Among several, carbonaceous nanovariants like carbon nanotubes (CNTs), fullerenes, and graphitic nanofibers reveal reversible hydrogen sorption characteristics at 77 K, due to their van der Waals interaction. The spillover mechanism combining Pd nanoparticles on the host metal-organic framework (MOF) show at room temperature uptake of hydrogen. Metal or complex hydrides either in the nanocomposite form and its subset, nanocatalyst dispersed alloy phases illustrate the concept of nanoengineering and nanoconfinement of particles with tailor-made properties for reversible hydrogen storage. Another class of materials comprising polymeric nanostructures such as conducting polyaniline and their functionalized nanocomposites are versatile hydrogen storage materials because of their unique size, high specific surface-area, pore-volume, and bulk properties. The salient features of nanocomposite materials for reversible hydrogen storage are reviewed and discussed.
  • 3.0K
  • 22 Jul 2020
Topic Review
Avocado-Derived Biomass
The avocado (Persea americana Mill.) is a tree native to Mexico and Guatemala, and currently it is cultivated in more than 70 countries. Avocado consumption, fresh or in the form of processed products, is growing everywhere and it has caused a large number of countries to invest heavily in avocado production. The industrialization of avocado gives as a result a huge amount of waste: peel, stone, tree pruning, and oil extraction wastes. Although the industrial application of these biomasses is still limited, numerous studies suggest that they can serve as raw materials to obtain bioenergy and different types of bioproducts. To take full advantage of them, it would particularly interesting to develop biorefinery models.
  • 3.0K
  • 27 Dec 2020
Topic Review
Aydın
Aydın (/ˈaɪdɪn/ EYE-din; Turkish: [ˈajdɯn]; formerly named Güzelhisar, Ancient and Modern Greek: Τράλλεις /Tralleis/) is a city in and the seat of Aydın Province in Turkey's Aegean Region. The city is located at the heart of the lower valley of Büyük Menderes River (ancient Meander River) at a commanding position for the region extending from the uplands of the valley down to the seacoast. Its population was 207,554 in 2014. Aydın city is located along a region which was famous for its fertility and productivity since ancient times. Figs remain the province's best-known crop, although other agricultural products are also grown intensively and the city has some light industry. At the crossroads of a busy transport network of several types, a six-lane motorway connects Aydın to İzmir, Turkey's second port, in less than an hour, and in still less time to the international Adnan Menderes Airport, located along the road between the two cities. A smaller airport, namely Aydın Airport, is located a few kilometers in the South-East of Aydın. The region of Aydın also pioneered the introduction of railways into Turkey in the 19th century and still has the densest railroad network. The province of Aydın is also where a number of internationally known historic sites and centers of tourism are concentrated.
  • 3.0K
  • 18 Nov 2022
Topic Review
Gravitational Influence
Gravity constituted the only constant environmental parameter, during the evolutionary period of living matter on Earth. However, whether gravity has affected the evolution of species, and its impact is still ongoing.
  • 3.0K
  • 14 Jul 2021
Topic Review
Polylactic Acid for Single-Use Laboratory Components
Sustainability needs have driven interest in polymers which are degradable, recyclable, and/or derived from eco-friendly input materials. Biomass-based polymers are one option with many benefits to sustainability: reducing dependence on fossil fuel extraction; produced from renewable resources; may make use of waste materials; and better biodegradability. Polylactic Acid (PLA) is one of the most commonly used bioplastics, in 2021 it was reported to hold the largest market share worldwidefor biodegradable bioplastics manufacturing capacity.
  • 3.0K
  • 06 May 2022
Topic Review
Dispersion
A dispersion is a system in which distributed particles of one material are dispersed in a continuous phase of another material. The two phases may be in the same or different states of matter. Dispersions are classified in a number of different ways, including how large the particles are in relation to the particles of the continuous phase, whether or not precipitation occurs, and the presence of Brownian motion. In general, dispersions of particles sufficiently large for sedimentation are called suspensions, while those of smaller particles are called colloids and solutions.
  • 3.0K
  • 11 Oct 2022
Topic Review
Thin-Layer Chromatography in the Screening of Botanicals
Thin-layer chromatography both in its standard (TLC) and high-performance (HPTLC) format is known as a versatile and high-throughput liquid chromatography technique, with a wide range of important applications. These applications can roughly be divided into those in direct service of life sciences (such as botany, phytochemistry and medicine, and handling rather fundamental issues such as contributing to chemotaxonomy of plants, or searching for enzyme inhibitor templates) and the more practical goals.
  • 3.0K
  • 19 Oct 2022
Topic Review
Zeolitic Imidazolate Framework
Zeolitic imidazolate frameworks (ZIFs) are a class of metal-organic frameworks that are topologically isomorphic with zeolites. ZIFs are composed of tetrahedrally-coordinated transition metal ions (e.g. Fe, Co, Cu, Zn) connected by imidazolate linkers. Since the metal-imidazole-metal angle is similar to the 145° Si-O-Si angle in zeolites, ZIFs have zeolite-like topologies. As of 2010, 105 ZIF topologies have been reported in the literature. Due to their robust porosity, resistance to thermal changes, and chemical stability, ZIF’s are being investigated for applications such as carbon capture.
  • 3.0K
  • 25 Oct 2022
Topic Review
Hyperspectral Remote Sensing and Plant
Hyperspectral remote sensing provides image data with very high spectral resolution. This high resolution allows subtle differences in plant health to be recognized. Such a multidimensional data space, generated by hyperspectral sensors, has given rise to new approaches and methods for analyzing hyperspectral data.
  • 3.0K
  • 31 Jan 2022
Topic Review
Computer Reservation System
A computer reservation system or central reservation system (CRS) is a computerized system used to store and retrieve information and conduct transactions related to air travel, hotels, car rental, or other activities. Originally designed and operated by airlines, CRSs were later extended for the use of travel agencies. Global distribution systems (GDS) book and sell tickets for multiple airlines. Most airlines have outsourced their CRSs to GDS companies, which also enable consumer access through Internet gateways. Modern GDS's typically allow users to book hotel rooms, rental cars, airline tickets as well as other activities and tours. They also provide access to railway reservations and bus reservations in some markets, although these are not always integrated with the main system. These are also used to relay computerized information for users in the hotel industry, making reservation and ensuring that the hotel is not overbooked. Airline reservations systems may be integrated into a larger passenger service system, which also includes an airline inventory system and a departure control system.
  • 3.0K
  • 17 Nov 2022
Topic Review
Dragon 2
Dragon 2 is a class of reusable spacecraft developed and manufactured by U.S. aerospace manufacturer SpaceX, intended as the successor to the Dragon cargo spacecraft. The spacecraft launches atop a Falcon 9 Block 5 rocket and returns via ocean splashdown. When compared to Dragon, Crew Dragon has larger windows, new flight computers and avionics, redesigned solar arrays, and a modified outer mold line. The spacecraft has two planned variants – Crew Dragon, a human-rated capsule capable of carrying up to seven astronauts, and Cargo Dragon, an updated replacement for the original Dragon. Crew Dragon is equipped with an integrated launch escape system in a set of four side-mounted thruster pods with two SuperDraco engines each. Crew Dragon has been contracted to supply the International Space Station (ISS) with crew under the Commercial Crew Program, with the initial award occurring in October 2014 alongside Boeing CST-100 Starliner. Crew Dragon's first non-piloted test flight to the ISS launched in March 2019. Cargo Dragon will supply the ISS with cargo under the Commercial Resupply Services-2 (CRS-2) after a January 2016 selection alongside Northrop Grumman Innovation Systems' Cygnus and Sierra Nevada Corporation's Dream Chaser. SpaceX's first CRS-2 mission with the Cargo Dragon is slated to occur in August 2020 after SpaceX's final CRS-20 mission with the original Dragon spacecraft. The Crew Dragon capsule that flew in the first test flight was scheduled to be used in a flight abort test before it unexpectedly exploded during a test of its SuperDraco engines on 20 April 2019. An investigation into the explosion was completed on 15 July 2019 and resulted in changes to vehicle plumbing. The in-flight abort test was conducted on 19 January 2020 at 15:30 UTC. The first crewed launch is scheduled for April 2020.
  • 3.0K
  • 29 Nov 2022
Topic Review
Non-Enzymatic Electrochemical Sensing
Simultaneous detection of analytes that together exist in biological organisms necessitates the development of effective and efficient non enzymatic electrodes in sensing. In this regard, development of sensing elements for detecting glucose and hydrogen peroxide (H2O2) is significant. The non-enzymatic sensing is more economical and has longer lifetime than enzymatic electrochemical sensing, but it has several drawbacks such as high working potential, slow electrode kinetics, poisoning from intermediate species and weak sensing parameters. Here is a comprehensive overview of the recent developments in non-enzymatic glucose and H2O2 (NEGH) sensing, by focusing mainly on sensing performance, electro catalytic mechanism, morphology and design of electrode materials. A comparison of glucose and H2O2 sensing parameters using same electrode materials is outlined to predict the efficient sensing performances of advanced nanomaterials with metal/metal oxides and hybrid metallic nanocomposites.
  • 3.0K
  • 24 Nov 2020
Topic Review
Blood Flow Modeling
Blood flow modeling consists of using computational techniques to investigate the blood flow behavior in a rapid and accurate fashion. This has become an area of extensive research due to the prevalence of cardiovascular diseases, responsible for a critical number of deaths every year worldwide, most of which are associated with atherosclerosis, a disease that causes unusual hemodynamic conditions in arteries. In the present review,  the application of computational simulations by using different physiological conditions of blood flow, several rheological models, and boundary conditions, were discussed.
  • 3.0K
  • 10 Apr 2021
Biography
Martin Lings
Martin Lings (24 January 1909 – 12 May 2005), also known as Abū Bakr Sirāj ad-Dīn, was an England writer, scholar, and philosopher. A student of the Swiss metaphysician Frithjof Schuon[1] and an authority on the work of William Shakespeare, he is best known as the author of Muhammad: His Life Based on the Earliest Sources, first published in 1983 and still in print. Lings was born in Bur
  • 3.0K
  • 09 Dec 2022
Topic Review Peer Reviewed
Residential Segregation
Residential segregation refers to the disproportionate distribution of population groups across a geographical area. Groups can be segregated on the basis of any characteristic (such as occupation, income, religion, age or ethnicity) and at any geographical scale. In most cases, segregation is, however, measured with regard to residential areas of a city. The extent of the unequal distribution of selected characteristics can be expressed by different statistical measures. Sociologists, economists and demographers have long studied how social groups tend to be differentiated in residential space and developed a broad range of explanations. As a consequence, segregation has been explained by a variety of theories, which are discussed in this paper. The topics examined by empirical research include temporal dynamics, geographical patterns, societal causes and effects on life chances. This entry focuses on major conceptual facts regarding residential segregation and only marginally discusses the methodological issues connected with its measurement.
  • 3.0K
  • 02 Nov 2023
Topic Review
Convolutional Neural Network + Recurrent Neural Network
A convolutional neural network and recurrent neural network (CNN + RNN) combination is an effective approach for many modern image recognition tasks that need to identify the behaviour of objects through a sequence of frames. For example, in a security CCTV camera footage, want to identify what abnormal actions a character is doing in the scene (e.g. fighting with someone, breaking into a store, etc.). A deep convolutional neural network (e.g. ResNet50) has many layers of abstraction and is good for extracting essential features in each frame of the input stream. These extracted features, which may represent low-level image features or even high-level objects, can be monitored over a sequence of frames by a recurrent neural network (e.g. ConvLSTM) so as to detect whether a certain action or event has happened.
  • 3.0K
  • 23 Feb 2022
Topic Review
Vitamin D-Fortified Beverages
Vitamin D is a lipophilic bioactive that plays an important role in bone health. Fortification of beverages, such as milk, fruit juices, teas, and vegetable drinks, could be an efficient strategy to prevent vitamin D deficiency and its associated effects on health. 
  • 3.0K
  • 28 Apr 2022
Topic Review
Tayra
The Tayra (Eira barbara) is a sleek and agile carnivorous mammal native to the forests of Central and South America. Also known as the "tolomuco" or "tolomuco real," this elusive mustelid is characterized by its slender body, dark fur, and a distinctive, bushy tail.
  • 3.0K
  • 08 Feb 2024
Topic Review
Chrysin
Pharmacological profile of phytochemicals has attracted much attention to their use in disease therapy. Since cancer is a major problem for public health with high mortality and morbidity worldwide, experiments have focused on revealing the anti-tumor activity of natural products. Flavonoids comprise a large family of natural products with different categories. Chrysin is a hydroxylated flavonoid belonging to the flavone category. Chrysin has demonstrated great potential in treating different disorders, due to possessing biological and therapeutic activities, such as antioxidant, anti-inflammatory, hepatoprotective, neuroprotective, etc. Over recent years, the anti-tumor activity of chrysin has been investigated, and in the present review, we provide a mechanistic discussion of the inhibitory effect of chrysin on proliferation and invasion of different cancer cells. Molecular pathways, such as Notch1, microRNAs, signal transducer and activator of transcription 3 (STAT3), nuclear factor-kappaB (NF-κB), PI3K/Akt, MAPK, etc., as targets of chrysin are discussed. The efficiency of chrysin in promoting anti-tumor activity of chemotherapeutic agents and suppressing drug resistance is described. Moreover, poor bioavailability, as one of the drawbacks of chrysin, is improved using various nanocarriers, such as micelles, polymeric nanoparticles, etc. This updated review will provide a direction for further studies in evaluating the anti-tumor activity of chrysin.
  • 3.0K
  • 13 Oct 2020
Topic Review
Oleaginous Yeasts
The production of lipids from oleaginous yeasts involves several stages starting from cultivation and lipid accumulation, biomass harvesting and finally lipids extraction. However, the complex and relatively resistant cell wall of yeasts limits the full recovery of intracellular lipids and usually solvent extraction is not sufficient to effectively extract the lipid bodies. A pretreatment or cell disruption method is hence a prerequisite prior to solvent extraction. In general, there are no recovery methods that are equally efficient for different species of oleaginous yeasts.
  • 3.0K
  • 08 Feb 2021
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