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Topic Review
One Tree Hill (New Zealand)
Maungakiekie / One Tree Hill is a 182-metre (597 ft) volcanic peak in Auckland, New Zealand. It is an important memorial place for both Māori and other New Zealanders. The suburb around the base of the hill is also called One Tree Hill. It is surrounded by the suburbs of Royal Oak to the west, and clockwise, Epsom, Greenlane, Oranga, and Onehunga. The summit provides views across the Auckland area, and allows visitors to see both of Auckland's harbours. The hill's scoria cones were erupted from three craters – one is intact and two have been breached by lava flows that rafted away part of the side of the scoria cone. Lava flows went in all directions, many towards Onehunga, covering an area of 20 square kilometres (7.7 sq mi), making it the second largest (in area covered) of the Auckland volcanic field, behind Rangitoto Island. The volcano erupted approximately 60,000 years ago.
  • 3.8K
  • 10 Nov 2022
Topic Review
Maya Script
Maya script, also known as Maya glyphs, was the writing system of the Maya civilization of Mesoamerica and is the only Mesoamerican writing system that has been substantially deciphered. The earliest inscriptions found which are identifiably Maya date to the 3rd century BCE in San Bartolo, Guatemala. Maya writing was in continuous use throughout Mesoamerica until the Spanish conquest of the Maya in the 16th and 17th centuries. Maya writing used logograms complemented with a set of syllabic glyphs, somewhat similar in function to modern Japanese writing. Maya writing was mistakenly called "hieroglyphics" or hieroglyphs by early European explorers of the 18th and 19th centuries who found its general appearance reminiscent of Egyptian hieroglyphs, although the two systems are unrelated. Modern Mayan languages are written using the Latin alphabet rather than Maya script.
  • 3.8K
  • 21 Nov 2022
Topic Review
Nimbarka Sampradaya
The Nimbarka Sampradaya (IAST: Nimbārka Sampradāya, Sanskrit निम्बार्क सम्प्रदाय), also known as the Hamsa Sampradāya, Kumāra Sampradāya, Catuḥ Sana Sampradāya and Sanakādi Sampradāya, is one of the four Vaiṣṇava Sampradāyas. It was founded by Nimbarka (c.7th century CE), and teaches the Vaishnava theology of Dvaitadvaita (dvaita-advaita) or "dualistic non-dualism." Dvaitadvaita states that humans are both different and non-different from Isvara, God or Supreme Being, and is also known as Bhedābheda (bheda-abheda) philosophy.
  • 3.8K
  • 10 Nov 2022
Topic Review
Wood-Eating Insects and Wood Eaters
Dead wood is rich in sugars and can serve as an energy source when digested, but it lacks other nutrients, preventing the growth, development, and maturation of saproxylophages. Prokaryotic N fixation partially mitigates the limitations on saproxylophages by the scarcity of N, often the most limiting nutrient, what does not mitigate co-limitation by other physiologically essential nutrients. Fungal transport can shape nutrient dynamics early in wood decay, rearranging extremely scarce nutritional composition of dead wood environment during its initial stage of decomposition and assisting saproxylophage growth and development. This nutritional enrichment of dead wood creates a nutritional niche for xylophages that allows them to grow, develop, and reach maturity. Therefore, xylophagous insects (considered as “wood-eaters”) are unable to gather the necessary amounts of nutritional elements from pure dead wood to grow and mature, but instead must utilize fungal tissues.
  • 3.8K
  • 30 Oct 2020
Topic Review
Nickel-Copper Alloys
Nickel-Copper (Ni-Cu) alloys exhibit simultaneously high strength and toughness (particularly, at cryogenic temperatures), excellent corrosion resistance, and may show good wear resistance. Therefore, they are widely used for manufacturing of (i) structural components of equipment in the chemical, oil, and marine industries, (ii) resistors and contacts in electrical and electronic equipment, (iii) corrosion resistant coatings, and (iv) fuel cells. Processing technologies includes bar forging, plate and tube rolling, wire drawing, heat treatment (for certain alloy compositions), powder and wire arc additive manufacturing, electrodeposition.
  • 3.8K
  • 26 Oct 2020
Topic Review
Ti/Al/X/Au Au-Contained Ohmic Contact Technique
AlGaN/GaN high electron mobility transistors (HEMTs) are regarded as promising candidates for a 5G communication system, which demands higher frequency and power. Source/drain ohmic contact is one of the key fabrication processes crucial to the device performance. Firstly, Aucontained metal stacks combined with RTA high-temperature ohmic contact schemes were presented and analyzed, including process conditions and contact formation mechanisms. Considering the issues with the Au-contained technique, the overview of a sequence of Au-free schemes is given and comprehensively discussed. In addition, in order to solve various problems caused by hightemperature conditions, novel annealing techniques including microwave annealing (MWA) and laser annealing (LA) were proposed to form Au-free low-temperature ohmic contact to AlGaN/GaN HEMT. The most popular metallization schemes of ohmic contact in AlGaN/GaN HEMT is Ti/Al/X/Au, where X can be Ni, Mo, Pt, Ta, Ir, etc.
  • 3.8K
  • 28 Jun 2022
Topic Review
In Vitro Lung Models
In vitro lung models are used to faithfully model basic human pathology and the complexity and diversity of human respiratory tissues and to study emerging viral respiratory pathogens and diseases. These models include conventional cell lines, primary human airway epithelial cell (hAEC) cultures, lung organoids, lung-on-a-chip technology, ex vivo lung perfusion (EVLP) models and human lung tissue explants.
  • 3.8K
  • 23 Jun 2021
Topic Review
Salinity Stress in Plants
Plant growth and development is adversely affected by different kind of stresses. One of the major abiotic stresses, salinity, causes complex changes in plants by influencing the interactions of genes. 
  • 3.8K
  • 05 Feb 2021
Topic Review
RBS-15
The RBS-15 (Robotsystem 15) is a long-range fire-and-forget surface-to-surface and air-to-surface anti-ship missile. The later version Mk. III has the ability to attack land targets as well. The missile was developed by the Swedish company Saab Bofors Dynamics.
  • 3.8K
  • 01 Dec 2022
Topic Review
Shipunov 2A42
The Shipunov 2A42 is a Soviet/Russian 30 mm autocannon. It is built by the Tulamashzavod Joint Stock Company.
  • 3.8K
  • 11 Oct 2022
Topic Review
Beech and Walnut Wood
Beech (Fagus orientalis Lipsky) forests in Iran are one of the most important sources of the hardwood species used for lumber, furniture, and interior object design due to its hardness, wear resistance, strength, and excellent bending capabilities. 
  • 3.8K
  • 29 Jul 2021
Topic Review
Erowid
Erowid, also called Erowid Center, is a 501(c)(3) non-profit educational organization that provides information about psychoactive plants and chemicals as well as activities and technologies that can produce altered states of consciousness such as meditation, lucid dreaming, transcranial magnetic stimulation, and electroceuticals. Erowid documents legal and illegal substances, including their intended and adverse effects. Information on Erowid's website is gathered from diverse sources including published literature, experts in related fields, and the experiences of the general public. Erowid acts as a publisher of new information as well as a library for the collection of documents and images published elsewhere.
  • 3.8K
  • 09 Oct 2022
Topic Review
Dental-Enamel Junction
Dentin-enamel junction (DEJ) is the boundary layer located between dentin and covering enamel. DEJ has a distinct chemical, mechanical and energetical features than surrounding tissues. Its role lies in the transport of materials between dentin and enamel. At the same time DEJ, mainly due to its scalloped structure, protects the dentin against diffusing of mechanical shocks originating at the enamel boundary.
  • 3.8K
  • 16 Jun 2021
Topic Review
Postal Censorship
Postal censorship is the inspection or examination of mail, most often by governments. It can include opening, reading and total or selective obliteration of letters and their contents, as well as covers, postcards, parcels and other postal packets. Postal censorship takes place primarily but not exclusively during wartime (even though the nation concerned may not be at war, e.g. Ireland during 1939–1945) and periods of unrest, and occasionally at other times, such as periods of civil disorder or of a state of emergency. Both covert and overt postal censorship have occurred. Historically, postal censorship is an ancient practice; it is usually linked to espionage and intelligence gathering. Both civilian mail and military mail may be subject to censorship, and often different organisations perform censorship of these types of mail. In 20th-century wars the objectives of postal censorship encompassed economic warfare, security and intelligence. The study of postal censorship is a philatelic topic of postal history.
  • 3.8K
  • 01 Dec 2022
Topic Review
GeForce 4 Series
The GeForce 4 series (codenames below) refers to the fourth generation of GeForce-branded graphics processing units (GPUs) manufactured by Nvidia. There are two different GeForce4 families, the high-performance Ti family, and the budget MX family. The MX family spawned a mostly identical GeForce4 Go (NV17M) family for the laptop market. All three families were announced in early 2002; members within each family were differentiated by core and memory clock speeds. In late 2002, there was an attempt to form a fourth family, also for the laptop market, the only member of it being the GeForce4 4200 Go (NV28M) which was derived from the Ti line.
  • 3.8K
  • 21 Oct 2022
Topic Review Peer Reviewed
Implementation of Blended Learning during COVID-19
Blended learning (BL) is a teaching model that combines face-to-face activities in the classroom with activities outside the classroom through the introduction of technology that is computer-based, distance, or mobile learning, among others. There are several BL models to adopt, depending on the importance and extent to which the technology is used. It brings great benefits to the learner and involves teachers in the design of new teaching methods.
  • 3.8K
  • 26 Oct 2022
Topic Review
Different Subclasses of Flavonoids
Flavonoids are natural compounds that are attracting great interest in the biomedical field thanks to the wide spectrum of their biological properties. Their employment as anticancer, anti-inflammatory, and antidiabetic drugs, as well as for many other pharmacological applications, is extensively investigated. 
  • 3.8K
  • 13 Mar 2023
Topic Review
Gabor-Domain Optical Coherence Microscopy
Gabor-domain optical coherence microscopy (GDOCM) is a high transverse resolution variant of spectral domain optical coherence tomography (SD-OCT). It was proposed to break the cellular resolution limit of optical coherence tomography (OCT). GDOCM achieves invariant transverse and axial resolutions of 2 micron in 3D by fusing together multiple volumetric images that are acquired employing a liquid lens to dynamically refocus at different depths inside the sample with no moving parts.
  • 3.8K
  • 29 Oct 2020
Topic Review
ZnO Photocatalysts for the Treatment of Wastewater
The presence of contaminants in wastewater, surface water, groundwater, and drinking water is a serious threat to human and environmental health. Their toxic effects and resistance towards conventional water treatment methods have compelled the scientific community to search for an environmentally friendly method that could efficiently degrade toxic contaminants. In this regard, visible light active photocatalysts have proved to be efficient in eliminating a wide variety of water toxins. A plethora of research activities have been carried out and significant amounts of funds are spent on the monitoring and removal of water contaminants, but relatively little attention has been paid to the degradation of persistent water pollutants. In this regard, nanoparticles of doped ZnO are preferred options owing to their low recombination rate and excellent photocatalytic and antimicrobial activity under irradiation of solar light. 
  • 3.8K
  • 18 Feb 2022
Topic Review
Solar Storm of August 1972
The solar storms of August 1972 were a historically powerful series of solar storms with intense to extreme solar flare, solar particle event, and geomagnetic storm components in early August 1972, during solar cycle 20. The storm caused widespread electric‐ and communication‐grid disturbances through large portions of North America as well as satellite disruptions. On August 4, 1972, the storm caused the accidental detonation of numerous U.S. naval mines near Haiphong, North Vietnam. The coronal cloud's transit time from the Sun to the Earth is the fastest ever recorded.
  • 3.8K
  • 05 Dec 2022
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