Subject:
All Disciplines Arts & Humanities Biology & Life Sciences Business & Economics Chemistry & Materials Science Computer Science & Mathematics Engineering Environmental & Earth Sciences Medicine & Pharmacology Physical Sciences Public Health & Healthcare Social Sciences
Sort:
Hottest Latest Alphabetical (A-Z) Alphabetical (Z-A)
Type:
All Topic Review Biography
Topic Review
Variability of Vertical Wind Shear
Vertical wind shear is caused by a wind of different speed or direction over a relatively short distance in the atmosphere.
  • 506
  • 17 Jun 2021
Topic Review
Varangian Guard
The Varangian Guard (Greek: Τάγμα τῶν Βαράγγων, Tágma tōn Varángōn) was an elite unit of the Byzantine Army, from the 10th to the 14th centuries, whose members served as personal bodyguards to the Byzantine Emperors. They are known for being primarily composed of Germanic peoples, specifically Norsemen from modern day Sweden (the Guard was formed approximately 200 years into the Viking Age) and Anglo-Saxons (after the Norman Conquest of England created an Anglo-Saxon diaspora, part of which found employment in Constantinople). The Rus' provided the earliest members of the Varangian Guard. They were in Byzantine service from as early as 874. The Guard was first formally constituted under Emperor Basil II in 988, following the Christianization of Kievan Rus' by Vladimir I of Kiev. Vladimir, who had recently usurped power in Kiev with an army of Varangian warriors, sent 6,000 men to Basil as part of a military assistance agreement. Basil's distrust of the native Byzantine guardsmen, whose loyalties often shifted, with fatal consequences, as well as the proven loyalty of the Varangians, many of whom had previously served in Byzantium, led the Emperor to employ them as his personal guardsmen. Immigrants from Sweden, Denmark , Norway and Iceland kept a predominantly Norse cast to the organization until the late 11th century. According to the late Swedish historian Alf Henrikson in his book Svensk Historia (History of Sweden), the Scandinavian Varangian guardsmen were recognized by long hair, a red ruby set in the left ear and ornamented dragons sewn on their chainmail shirts. In these years, Scandinavian men left to enlist in the Byzantine Varangian Guard in such numbers that a medieval Swedish law, Västergötlagen, from Västergötland declared no one could inherit while staying in "Greece"—the then Scandinavian term for the Byzantine Empire—to stop the emigration, especially as two other European courts simultaneously also recruited Scandinavians: Kievan Rus' c. 980–1060 and London 1018–1066 (the Þingalið). Composed primarily of Norsemen and Rus for the first 100 years, the Guard began to see increased numbers of Anglo-Saxons after the Norman conquest of England. By the time of the Emperor Alexios Komnenos in the late 11th century, the Varangian Guard was largely recruited from Anglo-Saxons and "others who had suffered at the hands of the Vikings and their cousins the Normans". The Anglo-Saxons and other Germanic peoples shared with the Vikings a tradition of faithful (to death if necessary) oath-bound service, and the Norman invasion of England resulted in many fighting men who had lost their lands and former masters and were looking for positions elsewhere. The Varangian Guard not only provided security for the Byzantine emperors, but also participated in many wars, often playing a decisive role, since they were usually deployed at critical moments of a battle. By the late 13th century, Varangians were mostly ethnically assimilated by the Byzantine Greeks, though the Guard remained in existence until at least mid-14th century. In 1400, there were still some people identifying themselves as "Varangians" in Constantinople.
  • 1.5K
  • 04 Nov 2022
Topic Review
Valorization of Bread Waste into Value-Added Products
Bread is a universal food that is sold and consumed across the entire social and geographical spectrum. Bread waste is currently of increasing interest, as it is considered a huge global issue with serious environmental impacts and significant economic losses that have become even greater in the post-pandemic years due to an increase in cereal prices, which has led to higher production costs and bread prices. Meanwhile, many efforts have been initiated in the past decades to investigate methods of repurposing bread residues into fuel and chemicals such as bioethanol, biohydrogen, succinic acid, and various added-value products that can be exploited in versatile industries.
  • 1.1K
  • 09 Dec 2022
Topic Review
Valorisation of Animal By-Products
The treatment and reduction of animal by-products has registered an increase in the awareness that this type of materials is underutilised and can represent a valuable resource if treated correctly. Consequently, it is no longer practical to dispose of animal by-products, especially when a significant amount of potential raw materials is produced, which can have a high economic potential through the production of new products with significant added value. The reuse and valorisation of animal by-products (ABPs) generated in the food retail sector can involve sending these by-products to another company/organisation or industry, where they will be processed in order to obtain added-value products. This type of valorisation originates an industrial symbiosis.
  • 1.0K
  • 22 Mar 2022
Topic Review
Validation of Aerosol Optical Depth and Characterization
The validation of aerosol optical depth and its characterization describes how important the use of multiple instrument in the study of aerosols. The content of this work highlights recent results in the use of satellite, ground-based and modeling method to study aerosols. 
  • 278
  • 25 Jul 2023
Topic Review
Uturunku
Uturunku (Quechua for jaguar, Hispanicized spellings Uturunco, Uturuncu) is a dormant volcano in the Cordillera de Lípez in Potosí Department, Bolivia. It is located in the Sur Lípez Province, San Pablo de Lípez Municipality. It is in the Central Volcanic Zone of the Andes, and its highest summit is 6,008 metres (19,711 ft) above sea level. The volcano has two summits, with a fumarole field between them. The volcano's landforms include lava domes and lava flows. The volcano was sporadically active during the Pleistocene, with the most recent eruption dated at 271,000 years ago. Since then, Uturunku has displayed fumarolic activity. Starting in 1992, satellite observations have indicated a large area of regional uplift centered on Uturunku, which has been interpreted as an indication of large-scale magma intrusion under the volcano. This might be a prelude to large-scale volcanic activity, including "supervolcanic" activity and caldera formation.
  • 520
  • 29 Sep 2022
Topic Review
Utilizing Mediterranean Plants to Remove Contaminants
The use of contaminated soils in food production imposes the need for the reduction in heavy metals concentrations, using various techniques, in order to eliminate the toxic effects of pollution and ensure safety in the consumption of agricultural products. Phytoremediation is a promising, effective, and publicly acceptable method to remove soils’ toxicity. The Mediterranean basin is a region of distinct climatic conditions with temporal variability and great floristic heterogeneity. Due to the high variability in landscapes paired with the warm, dry summers and cool, wet winters, the Mediterranean hosts significant plant diversity, including numerous endemic and rare plant species
  • 486
  • 21 Mar 2022
Topic Review
Utilization Methods for Lignocellulosic Biomass
Utilization of lignocellulosic biomass (LCB) for bioenergy production has been widely investigated in the previous decades, as it provides an excellent environmentally friendly alternative to non-renewable energy sources. There are numerous procedures to convert plant-based biomass into usable feedstock or valuable energy carriers, such as C5 and C6 sugars, organic acids, or more commonly, bioethanol and biogas. 
  • 145
  • 23 Oct 2023
Topic Review
Using Storytelling as a Means Of Teaching
Storytelling was an important part of my culture and an intrinsic part of people’s way of life. As I grew up and went to school, storytelling was one the ways of learning and conveying important information about the culture, world views, morals, expectations, norms and values. 
  • 101
  • 03 Jan 2024
Topic Review
Using Remote Sensing to Detect Suspended Sediment
Glacier-fed hydrological systems in high latitude regions experience high seasonal variation in meltwater runoff. The peak in runoff usually coincides with the highest air temperatures which drive meltwater production. This process is often accompanied by the release of sediments from within the glacier system that are transported and suspended in high concentrations as they reach the proglacial realm. Sediment-laden meltwater is later transported to the marine environment and is expressed on the surface of fjords and coastal waters as sediment plumes. Direct monitoring of these processes requires complex and time-intensive fieldwork, meaning studies of these processes are rare. 
  • 488
  • 13 Jul 2022
  • Page
  • of
  • 271
Featured Entry Collections
>>

Featured Books

>>
Encyclopedia of Social Sciences
Encyclopedia of COVID-19
Encyclopedia of Fungi
Encyclopedia of Digital Society, Industry 5.0 and Smart City
Video Production Service
Feedback