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Topic Review
Indoor Air Pollution in Developing Nations
Indoor air pollution in developing nations is a significant form of indoor air pollution (IAP) that is little known to those in the developed world. Three billion people in developing countries across the globe rely on biomass, in the form of wood, charcoal, dung, and crop residue, as their domestic cooking fuel. Since much of the cooking is carried out indoors in environments that lack proper ventilation, millions of people, primarily poor women and children face serious health risks. The major sources of indoor air pollution include combustion and building materials. Globally, 4.3 million deaths were attributed to exposure to IAP in developing countries in 2012, almost all in low and middle-income countries. The South East Asian and Western Pacific regions bear most of the burden with 1.69 and 1.62 million deaths, respectively. Almost 600,000 deaths occur in Africa, 200,000 in the Eastern Mediterranean region, 99,000 in Europe and 81,000 in the Americas. The remaining 19,000 deaths occur in high-income countries. Even though the rate of dependence on biomass fuel is declining, this dwindling resource will not keep up with population growth which could ultimately put environments at even greater risk. Over the past several decades, there have been numerous studies investigating the air pollution generated by traditional household solid fuel combustion for space heating, lighting, and cooking in developing countries. It is now well established that, throughout much of the developing world, indoor burning of solid fuels (biomass, coal, etc.) by inefficient, often insufficiently vented, combustion devices results in elevated exposure to household air pollutants. This is due to the poor combustion efficiency of the combustion devices and the elevated nature of the emissions. In addition, they are often released directly into living areas. Smoke from traditional household solid fuel combustion commonly contains a range of incomplete combustion products, including both fine and coarse particulate matter (e.g., PM2.5, PM10), carbon monoxide (CO), nitrogen dioxide (NO2), sulfur dioxide (SO2), and a variety of organic air pollutants (e.g., formaldehyde, 1,3-butadiene, benzene, acetaldehyde, acrolein, phenols, pyrene, benzopyrene, benzo(a)pyrene, dibenzopyrenes, dibenzocarbazoles, and cresols). In a typical solid fuel stove, about 6–20% of the solid fuel is converted into toxic emissions (by mass). The exact quantity and relative composition is determined by factors such as the fuel type and moisture content, stove type and operation influencing the amount. While many pollutants can evolve, most measurements have been focused on breathing-zone exposure levels of particulate matter (PM) and carbon monoxide (CO), which are the main products of incomplete combustion and are considered to pose the greatest health risks. Indoor PM2.5 exposure levels have been consistently reported to be in the range of hundreds to thousands of micrograms per cubic meter (μg/m3). Similarly, CO exposure levels have been measured to be as high as hundreds to greater than 1000 milligrams per cubic meter (mg/m3). A recent study of 163 households in two rural Chinese counties reported geometric mean indoor PM2.5 concentrations of 276 μg/m3 (combinations of different plant materials, including wood, tobacco stems, and corncobs), 327 μg/m3 (wood), 144 μg/m3 (smoky coal), and 96 μg/m3 (smokeless coal) for homes using a variety of different fuel types and stove configurations (e.g., vented, unvented, portable, fire pit, mixed ventilation stove).
  • 2.9K
  • 22 Nov 2022
Topic Review
Degua Tembien
Dogu'a Tembien (Template:Lang-ti, "Upper Tembien", sometimes transliterated as Degua Tembien) is one of the woredas in the Tigray Region of Ethiopia. It is named in part after the former province of Tembien. Nowadays, the mountainous district is part of the Southeastern Tigray Zone. The administrative centre of this woreda is Hagere Selam.
  • 2.9K
  • 01 Nov 2022
Topic Review
Flashline Mars Arctic Research Station
The Flashline Mars Arctic Research Station (FMARS) is the first of two simulated Mars habitats (or Mars Analog Research Stations) established and maintained by the Mars Society.
  • 2.9K
  • 10 Oct 2022
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.
  • 2.9K
  • 18 Nov 2022
Topic Review
Karratha, Western Australia
Karratha is a city in the Pilbara region of Western Australia, adjoining the port of Dampier. It was established in 1968 to accommodate the processing and exportation workforce of the Hamersley Iron mining company and, in the 1980s, the petroleum and liquefied natural gas operations of the North West Shelf Venture. At June 2018, Karratha had an urban population of 16,708. The city's name comes from the cattle station of the same name, which derives from a word in a local Aboriginal language meaning "good country" or "soft earth". The city is the seat of government of the City of Karratha, a local government area covering the surrounding region.
  • 2.9K
  • 30 Sep 2022
Topic Review
Selenography
Selenography is the study of the surface and physical features of the Moon. Historically, the principal concern of selenographists was the mapping and naming of the lunar maria, craters, mountain ranges, and other various features. This task was largely finished when high resolution images of the near and far sides of the Moon were obtained by orbiting spacecraft during the early space era. Nevertheless, some regions of the Moon remain poorly imaged (especially near the poles) and the exact locations of many features (like crater depths) are uncertain by several kilometers. Today, selenography is considered to be a subdiscipline of selenology, which itself is most often referred to as simply "lunar science." The word selenography is derived from the Greek lunar deity Σελήνη Selene and γράφω graphō, "I write".
  • 2.9K
  • 11 Nov 2022
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.
  • 2.9K
  • 04 Nov 2022
Topic Review
Taupo Volcano
Lake Taupo, in the centre of New Zealand’s North Island, is the caldera of a large rhyolitic supervolcano called the Taupo Volcano. This huge volcano has produced two of the world’s most violent eruptions in geologically recent times. The Taupo Volcano forms part of the Taupo Volcanic Zone, a region of volcanic activity that extends from Ruapehu in the South, through the Taupo and Rotorua districts, to White Island, in the Bay of Plenty region. Taupo began erupting about 300,000 years ago, but the main eruptions that still affect the surrounding landscape are the Oruanui eruption, about 26,500 years ago, which is responsible for the shape of the modern caldera, and the Hatepe eruption, dated 232 ± 5 CE. However, there have been many more eruptions, with major ones every thousand years or so (see timeline of last 10,000 years of eruptions). Considering recent history alone, the volcano has been inactive for an unusually long period of time, but considering its long-term activity, it was inactive for much longer between 8100 and 5100 BCE (3,000 year inactivity, compared to the current 1,800 years). Some volcanoes within the Taupo Volcanic Zone have erupted far more recently, however, notably a violent VEI-5 eruption of Mount Tarawera in 1886, and frequent activity of Whakaari/White Island, which erupted most recently in December 2019.
  • 2.8K
  • 18 Oct 2022
Topic Review
Multiple Attribute-based Decision-making Models
Sustainability of agricultural practices depends on economic, environmental, and social conditions. The Rajasthan state of India has arid climatic conditions where kharif crops are commonly grown. In this work, the four major criteria are considered such as the farm area, crop yield per unit area, the cost prices, and the market sales price. Merged analytic hierarchy process (AHP) and entropy techniques have been employed to give reasonable weight coefficients for the objective and subjective weights to each criterion. Multiple attribute-based decision-making models (MADM) have been developed using three proven techniques, namely the Exprom2, the technique for order of preference by similarity to ideal solution (TOPSIS), and the VlseKriterijumska Optimizacija I KompromisnoResenje (VIKOR). The crop Pennisetum glaucum emerged as the most productive kharif crop in the arid climatic conditions of Rajasthan, India under the given criteria. The sensitivity analysis of the three methods identifies the most significant criteria and validates that Pennisetum glaucum is the first ranked crop despite the interchange of the weights. The methodology used in this study may be applied across the globe to select appropriate crops for maximizing the profit, optimizing the natural resources, and promoting sustainable agricultural practices. This study may be used to enhance the agricultural gross domestic product (GDP) to make the agriculturalists self-sufficient and to help the state policymakers in making elective regional policies.
  • 2.8K
  • 05 Nov 2020
Topic Review
Locative Media
Locative media or location-based media (LBM) are media of communication functionally bound to a location. The physical implementation of locative media, however, is not bound to the same location to which the content refers. Location-based media delivers multimedia and other content directly to the user of a mobile device dependent upon their location. Location information determined by means such as mobile phone tracking and other emerging real-time locating system technologies like Wi-Fi or RFID can be used to customize media content presented on the device. Locative media are digital media applied to real places and thus triggering real social interactions. While mobile technologies such as the Global Positioning System (GPS), laptop computers and mobile phones enable locative media, they are not the goal for the development of projects in this field.
  • 2.8K
  • 24 Oct 2022
Topic Review
Alcohol Belts of Europe
The alcohol belts of Europe divide Europe by their traditional alcoholic beverages: beer, wine, or spirits. They do not necessarily correspond with current drinking habits, as beer has become the most popular alcoholic drink world-wide. The definitions of these belts are not completely objective.
  • 2.8K
  • 25 Oct 2022
Topic Review
List of Minerals I (Complete)
This list includes those recognised minerals beginning with the letter I. The International Mineralogical Association is the international group that recognises new minerals and new mineral names, however minerals discovered before 1959 did not go through the official naming procedure, although some minerals published previously have been either confirmed or discredited since that date. This list contains a mixture of mineral names that have been approved since 1959 and those mineral names believed to still refer to valid mineral species (these are called "grandfathered" species). The list is divided into groups: The data was exported from mindat.org on 29 April 2005; updated up to 'IMA2018'. The minerals are sorted by name, followed by the structural group (rruff.info/ima and ima-cnmnc by mineralienatlas.de, mainly) or chemical class (mindat.org and basics), the year of publication (if it's before of an IMA approval procedure), the IMA approval and the Nickel–Strunz code. The first link is to mindat.org, the second link is to webmineral.com, and the third is to the Handbook of Mineralogy (Mineralogical Society of America).
  • 2.7K
  • 20 Oct 2022
Topic Review
Burmese Amber
Burmese amber, also known as Burmite or Kachin amber, is amber from the Hukawng Valley in northern Myanmar. The amber is dated to around 99 million years old, during the earliest part of the Cenomanian age of the Late Cretaceous. The amber is of significant palaeontological interest due to the diversity of flora and fauna contained as inclusions, particularly arthropods including insects and arachnids but also birds, lizards, snakes, frogs and fragmentary dinosaur remains. The amber has been known and commercially exploited since the first century AD, and has been known to science since the mid-nineteenth century. Research on the deposit has attracted controversy due to its role in funding internal conflict in Myanmar and hazardous working conditions in the mines where it is collected.
  • 2.7K
  • 24 Nov 2022
Topic Review
Hydrogen Production in Arctic Region
The development of markets for low-carbon energy sources requires reconsideration of issues related to extraction and use of oil and gas. Significant reserves of hydrocarbons are concentrated in Arctic territories, e.g., 30% of the world’s undiscovered natural gas reserves and 13% of oil. Associated petroleum gas, natural gas and gas condensate could be able to expand the scope of their applications. Natural gas is the main raw material for the production of hydrogen and ammonia, which are considered promising primary energy resources of the future, the oxidation of which does not release CO2. Complex components contained in associated petroleum gas and gas condensate are valuable chemical raw materials to be used in a wide range of applications.
  • 2.7K
  • 17 Apr 2024
Topic Review
Santa Cruz Province, Argentina
Santa Cruz Province (Spanish: Provincia de Santa Cruz, Spanish pronunciation: [ˈsanta ˈkɾus], 'Holy Cross') is a province of Argentina , located in the southern part of the country, in Patagonia. It borders Chubut Province to the north, and Chile to the west and south, with an Atlantic coast on its east. Santa Cruz is the second-largest province of the country (after Buenos Aires Province), and the least densely populated in mainland Argentina. The indigenous people of the province are the Tehuelches, who despite European exploration from the 16th century onwards, retained independence until the late 19th century. Soon after the Conquest of the Desert in the 1870s, the area was organised as the Territory of Santa Cruz, named after its original capital in Puerto Santa Cruz. The capital moved to Rio Gallegos in 1888 and has remained there ever since. Immigrants from various European countries came to the territory in the late 19th and early 20th century during a gold rush. Santa Cruz became a province of Argentina in 1957.
  • 2.7K
  • 30 Oct 2022
Topic Review
Small-Scale Rice Processing in Nigeria
Rice processing is an important part of Nigeria’s agricultural sector and has the potential to bring significant value to the country. Rice is a staple food in Nigeria and an important food and calorie source for the population.
  • 2.7K
  • 19 Jan 2024
Topic Review
Fossil Fuels Lobby
"Fossil fuels lobby" is a term used to label the paid representatives of large fossil fuel (oil, gas, coal) and electric utilities corporations who attempt to influence governmental policy. So-called Big Oil companies such as ExxonMobil, Royal Dutch Shell, BP, Total S.A., Chevron Corporation, and ConocoPhillips are amongst the largest corporations associated with the fossil fuels lobby. General Electric, Southern Company, First Energy, and the Edison Electric Institute are also among the most influential electric utilities corporations. By sector, "Energy/Nat Resource" comes fifth, behind "Misc Business", "Finance/Insur/RealEst", Health and "Communic/Electronics".
  • 2.6K
  • 27 Oct 2022
Topic Review
Geobiology
Geobiology is a field of scientific research that explores the interactions between the physical Earth and the biosphere. It is a relatively young field, and its borders are fluid. There is considerable overlap with the fields of ecology, evolutionary biology, microbiology, paleontology, and particularly soil science and biogeochemistry. Geobiology applies the principles and methods of biology, geology, and soil science to the study of the ancient history of the co-evolution of life and Earth as well as the role of life in the modern world. Geobiologic studies tend to be focused on microorganisms, and on the role that life plays in altering the chemical and physical environment of the pedosphere, which exists at the intersection of the lithosphere, atmosphere, hydrosphere and/or cryosphere. It differs from biogeochemistry in that the focus is on processes and organisms over space and time rather than on global chemical cycles. Geobiological research synthesizes the geologic record with modern biologic studies. It deals with process - how organisms affect the Earth and vice versa - as well as history - how the Earth and life have changed together. Much research is grounded in the search for fundamental understanding, but geobiology can also be applied, as in the case of microbes that clean up oil spills. Geobiology employs molecular biology, environmental microbiology, organic geochemistry, and the geologic record to investigate the evolutionary interconnectedness of life and Earth. It attempts to understand how the Earth has changed since the origin of life and what it might have been like along the way. Some definitions of geobiology even push the boundaries of this time frame - to understanding the origin of life and to the role that humans have played and will continue to play in shaping the Earth in the Anthropocene.
  • 2.6K
  • 04 Nov 2022
Topic Review
Ciolo (Apulia)
Ciolo is a narrow coastal inlet and a site of historical and environmental interest, which is located in Apulia, Italy. The location is also known as a geological site and for the presence of numerous sea caves, the largest one being the Grotta del Ciolo. Since October 2006 the Ciolo's area has become part of the Regional Park "Costa Otranto - Santa Maria di Leuca e Bosco di Tricase", created by the Apulia region to protect the eastern coast of Salento, specifically the architectural assets as well as important animal and plant species. The name Ciolo comes from the noun in salentino dialect "ciole", which refers to crows or magpies, which are widespread in this region.
  • 2.6K
  • 14 Nov 2022
Topic Review
List of Minerals D (Complete)
This list includes those recognised minerals beginning with the letter D. The International Mineralogical Association is the international group that recognises new minerals and new mineral names, however minerals discovered before 1959 did not go through the official naming procedure, although some minerals published previously have been either confirmed or discredited since that date. This list contains a mixture of mineral names that have been approved since 1959 and those mineral names believed to still refer to valid mineral species (these are called "grandfathered" species). The list is divided into groups: The data was exported from mindat.org on 29 April 2005; updated up to 'IMA2018'. The minerals are sorted by name, followed by the structural group (rruff.info/ima and ima-cnmnc by mineralienatlas.de, mainly) or chemical class (mindat.org and basics), the year of publication (if it's before of an IMA approval procedure), the IMA approval and the Nickel–Strunz code. The first link is to mindat.org, the second link is to webmineral.com, and the third is to the Handbook of Mineralogy (Mineralogical Society of America).
  • 2.6K
  • 05 Nov 2022
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