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Topic Review
Black Soldier Fly
The black soldier fly (BSF), Hermetia illucens Linnaeus, is a large Stratiomyidae fly (13-20 mm in size) found worldwide, but it is believed to have originated in the Americas. It is frequently found in the tropics and temperate regions throughout the world. Although adapted primarily to these regions, it can tolerate wide extremes of temperature except when ovipositing. They are considered beneficial insects and non-pests. The adult fly does not have mouthparts, stingers, or digestive organs; thus, they do not bite or sting and do not feed during its short lifespan. They feed only as larvae and are, therefore, not associated with disease transmission. BSF larvae (BSFL) are voracious eaters of a wide range of organic wastes, decomposing and returning nutrients to the soil. Additionally, BSFL is an alternative protein source for aquaculture, pet food, livestock feed, and human nutrition.
  • 28644
  • 25 Apr 2023
Topic Review
Chemtrail Conspiracy Theory
The chemtrail conspiracy theory posits the erroneous belief that long-lasting condensation trails are "chemtrails" consisting of chemical or biological agents left in the sky by high-flying aircraft, sprayed for nefarious purposes undisclosed to the general public. Believers in this conspiracy theory say that while normal contrails dissipate relatively quickly, contrails that linger must contain additional substances. Those who subscribe to the theory speculate that the purpose of the chemical release may be solar radiation management, weather modification, psychological manipulation, human population control, biological or chemical warfare, or testing of biological or chemical agents on a population, and that the trails are causing respiratory illnesses and other health problems. The claim has been dismissed by the scientific community. There is no evidence that purported chemtrails differ from normal water-based contrails routinely left by high-flying aircraft under certain atmospheric conditions. Although proponents have tried to prove that chemical spraying occurs, their analyses have been flawed or based on misconceptions. Because of the persistence of the conspiracy theory and questions about government involvement, scientists and government agencies around the world have repeatedly explained that the supposed chemtrails are in fact normal contrails. The term chemtrail is a portmanteau of the words chemical and trail, just as contrail is a portmanteau of condensation and trail.
  • 13404
  • 31 Oct 2022
Topic Review
Temperate Climate
In geography, the temperate or tepid climates of Earth occur in the middle latitudes, which span between the tropics and the polar regions of Earth. In most climate classifications, temperate climates refer to the climate zone between 35 and 50 north and south latitudes (between the subarctic and subtropical climates). These zones generally have wider temperature ranges throughout the year and more distinct seasonal changes compared to tropical climates, where such variations are often small. They typically feature four distinct seasons, Summer the warmest, Autumn the transitioning season to Winter, the colder season, and Spring the transitioning season from winter back into summer. In the northern hemisphere, the year starts with winter, transitions in the first half year through spring into summer, which is in mid-year, then at the second half year through autumn into winter at year-end. In the southern hemisphere, the seasons are swapped, with summer between years and winter in mid-year. The temperate zones (latitudes from 23.5° to the polar circles at about 66.5°, north and south) are where the widest seasonal changes occur, with most climates found in it having some influence from both the tropics and the poles. The subtropics (latitudes from about 23.5° to 35°, north and south) have temperate climates that have the least seasonal change and the warmest in winter, while at the other end, Boreal climates located from 55 to 65 north latitude have the most seasonal changes and long and severe winters. In temperate climates, not only do latitudinal positions influence temperature changes, but sea currents, prevailing wind direction, continentality (how large a landmass is), and altitude also shape temperate climates. The Köppen climate classification defines a climate as "temperate" when the mean temperature is above −3 °C (26.6 °F) but below 18 °C (64.4 °F) in the coldest month. However, other climate classifications set the minimum at 0 °C (32.0 °F).
  • 13147
  • 08 Nov 2022
Topic Review
Environmental Impact of Shipping
The environmental impact of shipping includes air pollution, water pollution, acoustic, and oil pollution. Ships are responsible for more than 18 percent of some air pollutants. It also includes greenhouse gas emissions. The International Maritime Organization (IMO) estimates that carbon dioxide emissions from shipping were equal to 2.2% of the global human-made emissions in 2012 and expects them to rise 50 to 250 percent by 2050 if no action is taken. There is a perception that cargo transport by ship is low in air pollutants, because for equal weight and distance it is the most efficient transport method, according to shipping researcher Alice Bows-Larkin. This is particularly true in comparison to air freight. However, because sea shipment accounts for far more annual tonnage and the distances are often large, shipping's emissions are globally substantial. A difficulty is that the annual increasing amount of shipping overwhelms gains in efficiency, such as from slow-steaming or the use of kites. The growth in tonne-kilometers of sea shipment has averaged 4 percent yearly since the 1990s, and it has grown by a factor of 5 since the 1970s. There are now over 100,000 transport ships at sea, of which about 6,000 are large container ships. The fact that shipping enjoys substantial tax privileges has contributed to the growing emissions.
  • 13031
  • 31 Oct 2022
Topic Review
History of the Middle East
Home to the Cradle of Civilization, the Middle East (usually interchangeable with the Near East) has seen many of the world's oldest cultures and civilizations. This history started from the earliest human settlements, continuing through several major pre- and post-Islamic Empires through to the nation-states of the Middle East today. Template:Human history Egyptian civilization coalesced around 3150 BC with the political unification of Upper and Lower Egypt under the first pharaoh. Mesopotamia was home to several powerful empires that came to rule almost the entire Middle East—particularly the Assyrian Empires of 1365–1076 BC and the Neo-Assyrian Empire of 911–609 BC. From the early 7th century BC and onwards, the Iranian Medes followed by Achaemenid Persia and other subsequent Iranian states empires dominated the region. In the 1st century BC, the expanding Roman Republic absorbed the whole Eastern Mediterranean, which included much of the Near East. The Eastern Roman Empire, today commonly known as the Byzantine Empire, ruling from the Balkans to the Euphrates, became increasingly defined by and dogmatic about Christianity, gradually creating religious rifts between the doctrines dictated by the establishment in Constantinople and believers in many parts of the Middle East. From the 3rd up to the course of the 7th century AD, the entire Middle East was dominated by the Byzantines and Sassanid Persia. From the 7th century, a new power was rising in the Middle East, that of Islam. The dominance of the Arabs came to a sudden end in the mid-11th century with the arrival of the Seljuq Turks. In the early 13th century, a new wave of invaders, the armies of the Mongol Empire, mainly Turkic, swept through the region. By the early 15th century, a new power had arisen in western Anatolia, the Ottoman emirs, linguistically Turkic and religiously Islamic, who in 1453 captured the Christian Byzantine capital of Constantinople and made themselves sultans. Large parts of the Middle East became a warground between the Ottomans and Iranian Safavids for centuries starting in the early 16th century. By 1700, the Ottomans had been driven out of Hungary and the balance of power along the frontier had shifted decisively in favor of the West. The British also established effective control of the Persian Gulf, and the French extended their influence into Lebanon and Syria. In 1912, the Italians seized Libya and the Dodecanese islands, just off the coast of the Ottoman heartland of Anatolia. In the late 19th and early 20th centuries, Middle Eastern rulers tried to modernize their states to compete more effectively with the European powers. A turning point in the history of the Middle East came when oil was discovered, first in Persia in 1908 and later in Saudi Arabia (in 1938) and the other Persian Gulf states, and also in Libya and Algeria. A Western dependence on Middle Eastern oil and the decline of British influence led to a growing American interest in the region. During the 1920s, 1930s, and 1940s, Syria and Egypt made moves towards independence. The British, the French, and the Soviets departed from many parts of the Middle East during and after World War II (1939–1945). The struggle between the Arabs and the Jews in Palestine culminated in the 1947 United Nations plan to partition Palestine. Later in the midst of Cold War tensions, the Arabic-speaking countries of Western Asia and Northern Africa saw the rise of pan-Arabism. The departure of the European powers from direct control of the region, the establishment of Israel, and the increasing importance of the oil industry, marked the creation of the modern Middle East. In most Middle Eastern countries, the growth of market economies was inhibited by political restrictions, corruption and cronyism, overspending on arms and prestige projects, and over-dependence on oil revenues. The wealthiest economies in the region per capita are the small oil-rich countries of Persian Gulf: Qatar, Kuwait, Bahrain, and the United Arab Emirates. A combination of factors—among them the 1967 Six-Day War, the 1970s energy crisis beginning with the 1973 OPEC oil embargo in response to U.S. support of Israel in the Yom Kippur War, the concurrent Saudi-led popularization of Salafism/Wahhabism, and the 1978-79 Iranian Revolution—promoted the increasing rise of Islamism and the ongoing Islamic revival (Tajdid). The Fall of the Soviet Union in 1991 brought a global security refocus from the Cold War to a War on Terror. Starting in the early 2010s, a revolutionary wave popularly known as the Arab Spring brought major protests, uprisings, and revolutions to several Middle Eastern and Maghreb countries. Clashes in western Iraq on 30 December 2013 were preliminary to the Sunni pan-Islamist ISIL uprising. The term Near East can be used interchangeably with Middle East, but in a different context, especially when discussing ancient times, it may have a limited meaning, namely the northern, historically Aramaic-speaking Semitic area and adjacent Anatolian territories, marked in the two maps below.
  • 11646
  • 27 Oct 2022
Topic Review
Northwestern European People
Northwestern European people are a pan-ethnic group, or multi-ethnic regional grouping, and the inhabitants of Northwestern Europe. Northwest or Northwestern Europeans can usually trace back full or partial heritage to Great Britain and Ireland, Northern Germany, Denmark , Sweden, Norway , the Netherlands, Northern France, Belgium, and other places connected to Northwestern Europe geographically or culturally. As the pan-ethnic group is also a cultural category, rather than exclusively geographical; it often can include peoples with ancestry from bordering regions such as Austria, Finland , Southern Germany, and Switzerland . There is a large Northwestern European diaspora, with significant numbers within North America (Northwestern European Americans and Northwestern European Canadians), and Northwestern European Australians in Oceania. Other subgroupings of Europeans include Eastern European people and Southern European people.
  • 10839
  • 28 Oct 2022
Topic Review
Environmental Risk Factors
Environmental health is a growing area of knowledge, continually increasing and updating the body of evidence linking the environment to human health.
  • 10195
  • 03 Dec 2022
Topic Review
Flood Prediction Using ML Models
Floods are among the most destructive natural disasters, which are highly complex to model. The research on the advancement of flood prediction models contributed to risk reduction, policy suggestion, minimization of the loss of human life, and reduction of the property damage associated with floods. To mimic the complex mathematical expressions of physical processes of floods, during the past two decades, machine learning (ML) methods contributed highly in the advancement of prediction systems providing better performance and cost-effective solutions. Due to the vast benefits and potential of ML, its popularity dramatically increased among hydrologists.Researchers through introducing novel ML methods and hybridizing of the existing ones aim at discovering more accurate and efficient prediction models. The main contribution of this paper is to demonstrate the state of the art of ML models in flood prediction and to give insight into the most suitable models. In this paper, the literature where ML models were benchmarked through a qualitative analysis of robustness, accuracy, effectiveness, and speed are particularly investigated to provide an extensive overview on the various ML algorithms used in the field. The performance comparison of ML models presents an in-depth understanding of the different techniques within the framework of a comprehensive evaluation and discussion. As a result, this paper introduces the most promising prediction methods for both long-term and short-term floods. Furthermore, the major trends in improving the quality of flood prediction models are investigated. Among them, hybridization, data decomposition, algorithm ensemble, and model optimization are reported as the most effective strategies for the improvement of ML methods. This survey can be used as a guideline for hydrologists as well as climate scientists in choosing the proper ML method according to the prediction task.
  • 8978
  • 04 Jan 2023
Topic Review
2004 Indian Ocean Tsunami in Malaysia
The tsunami is one of the deadliest natural disasters, responsible for more than 260,000 deaths and billions in economic losses over the last two decades. The footage of the devastating power of the 2004 Indian Ocean tsunami perhaps remains vivid in the memory of most survivors, and Malaysia was one of the countries affected by the unprecedented 2004 tsunami. It was the first time the Malaysian government had managed such a great disaster. A compilation of post-event observations regarding tsunami characteristics is first presented in the form of maps, followed by building damage, including damage modes of wall failure, total collapse, debris impact and tilting of structures.
  • 8659
  • 25 Aug 2022
Topic Review
Water Quality Index
A critical water quality index (WQI) method has been used to determine the overall water quality status of surface water and groundwater systems globally since the 1960s. WQI follows four steps: parameter selection, sub-indices, establishing weights, and final index aggregation.
  • 8441
  • 09 Apr 2021
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