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176-406: Aquaculture can also be defined as the breeding, growing, and harvesting of fish and other aquatic plants, also known as farming in water. It is an environmental source of food and commercial products that help to improve healthier habitats and are used to reconstruct the population of endangered aquatic species. Technology has increased the growth of fish in coastal marine waters and open oceans due to

352-410: A marker gene . This gene, called GFP , or green fluorescent protein, would cause live samples of the virus to glow green under fluorescent light. The insertion of this gene, which would not influence the virulence of the virus, would be the only allowed modification of the genome. The committee stated the proposed modification would aid in research of treatments by making it easier to assess whether

528-472: A saltwater aquarium , though he did not use the term. In 1846, Anne Thynne maintained stony corals and seaweed for almost three years, and was credited as the creator of the first balanced marine aquarium in London. English chemist Robert Warington experimented with a 13-gallon container, which contained goldfish, eelgrass , and snails , creating one of the first stable aquaria. The aquarium principle

704-414: A 400-litre (110 US gal; 88 imp gal) tank with many other fish in it represents only a minor change. For this reason, hobbyists often favor larger tanks, as they require less attention. Several nutrient cycles are important in the aquarium. Dissolved oxygen enters the system at the surface water-air interface. Similarly, carbon dioxide escapes the system into the air. The phosphate cycle

880-1166: A challenge to recreate such environments, and most "true" biotopes will only have a few (if not only one) species of fish and invertebrates. Finally, an emerging concept for the home is that of a wall mounted aquarium, some of which are displayed at the Living Art Marine Center . An aquarium can range from a small glass bowl containing less than 1 litre (2.1 US pt) of water to immense public aquaria that house entire ecosystems such as kelp forests . Relatively large home aquaria resist rapid fluctuations of temperature and pH , allowing for greater system stability. Beginner aquarists are advised to consider larger tanks to begin with, as controlling water parameters in smaller tanks can prove difficult. Small, unfiltered bowl-shaped aquaria are now widely regarded as unsuitable for most fish. In order to keep water conditions at suitable levels, aquariums should contain at least two forms of filtration : biological and mechanical. Chemical filtration should also be considered under some circumstances for optimum water quality. Chemical filtration

1056-420: A circular, submerged lid. Pseudokreisels are "U" or semicircle shaped, usually without a lid. Stretch kreisels are a "double gyre" kreisel design, where the tank length is at least twice the height. Using two downwelling inlets on both sides of the tank lets gravity create two gyres in the tank. A single downwelling inlet may be used in the middle as well. The top of a stretch kreisel may be open or closed with

1232-443: A clinical case was observed, smallpox was confirmed using laboratory tests. Microscopically , poxviruses produce characteristic cytoplasmic inclusion bodies , the most important of which are known as Guarnieri bodies , and are the sites of viral replication . Guarnieri bodies are readily identified in skin biopsies stained with hematoxylin and eosin, and appear as pink blobs. They are found in virtually all poxvirus infections but

1408-425: A cooler environment. Temperature consistency is more important than range. Most organisms are not accustomed to sudden changes in temperatures, which can cause shock and lead to disease. Water temperature can be regulated with a thermostat and heater (or cooler). Water movement can also be important in simulating a natural ecosystem. Aquarists may prefer anything from still water up to swift currents , depending on

1584-444: A dazzling aquarium is one of the last surefire ways to impress their peers." A kreisel tank ( kreisel being German for " spinning top " or " gyroscope ") is an aquarium shaped like a horizontal cylinder that is designed to hold delicate animals such as jellyfish and newborn seahorses. These aquariums provide slow, circular water flow with a bare minimum of interior hardware to prevent the inhabitants from becoming injured by pumps or

1760-415: A discrete rash, in which the pustules stood out on the skin separately. The distribution of the rash was most dense on the face, denser on the extremities than on the trunk, and denser on the distal parts of the extremities than on the proximal. The palms of the hands and soles of the feet were involved in most cases. Sometimes, the blisters merged into sheets, forming a confluent rash, which began to detach

1936-518: A doctor in Berkeley, Gloucestershire , rural England, discovered that immunity to smallpox could be produced by inoculating a person with material from a cowpox lesion. Cowpox is a poxvirus in the same family as variola. Jenner called the material used for inoculation vaccine from the root word vacca , which is Latin for cow. The procedure was much safer than variolation and did not involve a risk of smallpox transmission. Vaccination to prevent smallpox

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2112-455: A fatality rate of around 30%, while variola minor’s mortality rate was about 1%. Throughout the 18th century, variola major was responsible for around 400,000 deaths annually in Europe alone. Survivors of the disease often faced lifelong consequences, such as blindness and severe scarring, which were nearly universal among those who recovered. In the first half of the 20th century, variola major

2288-466: A growing demand for high-quality protein, encouraged aquaculturists to domesticate other marine species. At the outset of modern aquaculture, many were optimistic that a " Blue Revolution " could take place in aquaculture, just as the Green Revolution of the 20th century had revolutionized agriculture. Although land animals had long been domesticated, most seafood species were still caught from

2464-614: A host cell varies across the poxviridae . Recombination of the genome occurs within actively infected cells. Following the onset of viral DNA replication, an intermediate set of genes codes for transcription factors of late gene expression. The products of the later genes include transcription factors necessary for transcribing the early genes for new virions, as well as viral RNA polymerase and other essential enzymes for new viral particles. These proteins are then packaged into new infectious virions capable of infecting other cells. Two live samples of variola major virus remain, one in

2640-421: A large scale and are most often taken in the wild. In 2016, aquaculture was the source of 96.5 percent by volume of the total 31.2 million tonnes of wild-collected and cultivated aquatic plants combined. Global production of farmed aquatic plants, overwhelmingly dominated by seaweeds, grew in output volume from 13.5 million tonnes in 1995 to just over 30 million tonnes in 2016. Seaweed farming or kelp farming

2816-624: A large toll in human lives. Most major human diseases originated in domesticated animals, including diseases such as smallpox and diphtheria , that like most infectious diseases, move to humans from animals. No human pathogens of comparable virulence have yet emerged from marine species. Biological control methods to manage parasites are already being used, such as cleaner fish (e.g. lumpsuckers and wrasse) to control sea lice populations in salmon farming. Models are being used to help with spatial planning and siting of fish farms in order to minimize impact. The decline in wild fish stocks has increased

2992-399: A lid. There may also be screens about midway down the sides of the tank, or at the top on the sides. It is possible to combine these designs; a circular shaped tank is used without a lid or cover, and the surface of the water acts as the continuation of circular flow. Another popular setup is the biotope aquarium. A biotope aquarium is a recreation of a specific natural environment. Some of

3168-408: A more extensive rash and higher fever. Variola minor is a less common presentation, causing less severe disease, typically discrete smallpox, with historical death rates of 1% or less. Subclinical ( asymptomatic ) infections with variola virus were noted but were not common. In addition, a form called variola sine eruptione (smallpox without rash) was seen generally in vaccinated persons. This form

3344-514: A natural water source (such as a river, lake, or ocean) to reduce the level of treatment. Some hobbyists use an algae scrubber to filter the water naturally. Water temperature determines the two most basic aquarium classifications: tropical versus cold water . Most fish and plant species tolerate only a limited temperature range; tropical aquaria, with an average temperature of about 25 °C (77 °F), are much more common. Temperate or coldwater aquaria are for fish that are better suited to

3520-433: A popular choice for many home and hobbyist aquarists for many years. Once silicone sealant became strong enough to ensure a long-term water-tight seal, it eliminated the need for a structural frame. In addition to lower cost, glass aquaria are more scratch resistant than acrylic. Although the price is one of the main considerations for aquarists when deciding which of these two types of aquaria to purchase, for very large tanks,

3696-601: A potential treatment was effective in killing viral samples. The recommendation could only take effect if approved by the WHA . When the WHA discussed the proposal in 2005, it refrained from taking a formal vote on the proposal, stating that it would review individual research proposals one at a time. Addition of the GFP gene to the Vaccinia genome is routinely performed during research on

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3872-423: A region of roughly 100 base pairs necessary for resolving concatomeric DNA (a stretch of DNA containing multiple copies of the same sequence), a few open reading frames , and short tandemly repeating sequences of varying number and length. The ITRs of poxviridae vary in length across strains and species. The coding sequence for most of the viral proteins in variola major virus have at least 90% similarity with

4048-465: A small glass bowl, a few liters in volume, to immense public aquaria of thousands of liters. Specialized equipment maintains appropriate water quality and other characteristics suitable for the aquarium's residents. In 1369, the Hongwu Emperor of China established a porcelain company that produced large porcelain tubs for maintaining goldfish ; over time, people produced tubs that approached

4224-421: A source of infection”; noted that “Current recommendations for control of secondary smallpox infections emphasize transmission ‘by expelled droplets to close contacts (those within 6–7 feet)’”; but warned that the “emphasis on spread via large droplets may reduce the vigilance with which more difficult airborne precautions [i.e. against finer droplets capable of traveling longer distances and penetrating deeply into

4400-401: A tank by diluting effects from death or contamination events that push an aquarium away from equilibrium. The bigger the tank, the easier such a systemic shock is to absorb, because the effects of that event are diluted. For example, the death of the only fish in an 11-litre (3 US gal; 2 imp gal) tank causes dramatic changes in the system, while the death of that same fish in

4576-416: A total output which is double that of the rest of the world put together. However, there are some historical issues with the accuracy of China's returns. In 2001, scientists Reg Watson and Daniel Pauly expressed concerns that China was over reporting its catch from wild fisheries in the 1990s. They said that made it appear that the global catch since 1988 was increasing annually by 300,000 tonnes, whereas it

4752-449: A tropical temperature and requires less capacity from an aquarium heater. Acrylic-soluble cements are used to directly fuse acrylic together. Acrylic allows for the formation of unusual shapes, such as the hexagonal tank. Acrylics are easier to scratch than glass, but unlike glass, scratches in acrylic can be polished out. Large aquaria might instead use stronger materials such as fiberglass -reinforced plastics . However, this material

4928-582: Is a severe form accompanied by extensive bleeding into the skin, mucous membranes, gastrointestinal tract, and viscera . This form develops in approximately 2% of infections and occurs mostly in adults. Pustules do not typically form in hemorrhagic smallpox. Instead, bleeding occurs under the skin, making it look charred and black, hence this form of the disease is also referred to as variola nigra or "black pox". Hemorrhagic smallpox has very rarely been caused by variola minor virus. While bleeding may occur in mild cases and not affect outcomes, hemorrhagic smallpox

5104-420: Is also a later form of hemorrhagic smallpox (referred to late hemorrhagic smallpox, or variolosa pustula hemorrhagica ). The prodrome is severe and similar to that observed in early hemorrhagic smallpox, and the fever persists throughout the course of the disease. Bleeding appears in the early eruptive period (but later than that seen in purpura variolosa ), and the rash is often flat and does not progress beyond

5280-490: Is also under research as a viral vector for vaccines for unrelated diseases. The genome of variola major virus was first sequenced in its entirety in the 1990s. The complete coding sequence is publicly available online. The current reference sequence for variola major virus was sequenced from a strain that circulated in India in 1967. In addition, there are sequences for samples of other strains that were collected during

5456-540: Is an especially important economic activity in China. Between 1980 and 1997, the Chinese Bureau of Fisheries reports, aquaculture harvests grew at an annual rate of 16.7%, jumping from 1.9 million tonnes to nearly 23 million tonnes. In 2005, China accounted for 70% of world production. Aquaculture is also currently one of the fastest-growing areas of food production in the U.S. About 90% of all U.S. shrimp consumption

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5632-431: Is an important, although often overlooked, nutrient cycle. Sulfur, iron, and micronutrients also cycle through the system, entering as food and exiting as waste. Appropriate handling of the nitrogen cycle , along with supplying an adequately balanced food supply and considered biological loading, is enough to keep these other nutrient cycles in approximate equilibrium. An aquarium must be maintained regularly to ensure that

5808-541: Is believed to have had a mortality rate of less than 1%, as compared to variola major's 30%. Like variola major, variola minor was spread through inhalation of the virus in the air, which could occur through face-to-face contact or through fomites. Infection with variola minor virus conferred immunity against the more dangerous variola major virus. Because variola minor was a less debilitating disease than smallpox, people were more frequently ambulant and thus able to infect others more rapidly. As such, variola minor swept through

5984-411: Is caused by infection with variola virus, which belongs to the family Poxviridae , subfamily Chordopoxvirinae , genus Orthopoxvirus . The date of the appearance of smallpox is not settled. It most probably evolved from a terrestrial African rodent virus between 68,000 and 16,000 years ago. The wide range of dates is due to the different records used to calibrate the molecular clock . One clade

6160-488: Is complicated by having multiple infectious forms, with differing mechanisms of cell entry. Poxviruses are unique among human DNA viruses in that they replicate in the cytoplasm of the cell rather than in the nucleus . To replicate, poxviruses produce a variety of specialized proteins not produced by other DNA viruses , the most important of which is a viral-associated DNA-dependent RNA polymerase . Both enveloped and unenveloped virions are infectious. The viral envelope

6336-447: Is consistent with the other published estimates, it suggests that the archaeological and historical evidence is very incomplete. Better estimates of mutation rates in these viruses are needed. Examination of a strain that dates from c.  1650 found that this strain was basal to the other presently sequenced strains. The mutation rate of this virus is well modeled by a molecular clock. Diversification of strains only occurred in

6512-509: Is estimated to have killed up to 300 million people in the 20th century and around 500 million people in the last 100 years of its existence. Earlier deaths included six European monarchs , including Louis XV of France in 1774. As recently as 1967, 15 million cases occurred a year. The final known fatal case occurred in the United Kingdom in 1978 . Inoculation for smallpox appears to have started in China around

6688-712: Is farmed and imported. In recent years, salmon aquaculture has become a major export in southern Chile, especially in Puerto Montt , Chile's fastest-growing city. A United Nations report titled The State of the World Fisheries and Aquaculture released in May 2014 maintained fisheries and aquaculture support the livelihoods of some 60 million people in Asia and Africa. FAO estimates that in 2016, overall, women accounted for nearly 14 percent of all people directly engaged in

6864-752: Is farmed for agar ; the rest are eaten after limited processing. Seaweeds are different from mangroves and seagrasses , as they are photosynthetic algal organisms and are non-flowering. The largest seaweed-producing countries as of 2022 are China (58.62%) and Indonesia (28.6%); followed by South Korea (5.09%) and the Philippines (4.19%). Other notable producers include North Korea (1.6%), Japan (1.15%), Malaysia (0.53%), Zanzibar ( Tanzania , 0.5%), and Chile (0.3%). Seaweed farming has frequently been developed to improve economic conditions and to reduce fishing pressure. The Food and Agriculture Organization (FAO) reported that world production in 2019

7040-436: Is frequently achieved via activated carbon , to filter medications, tannins , and/or other known impurities from the water. Reef aquaria under 100 litres (26 US gal; 22 imp gal) have a special place in the aquarium hobby; these aquaria, termed nano reefs (when used in reefkeeping), have a small water volume, under 40 litres (11 US gal; 9 imp gal). Practical limitations, most notably

7216-533: Is generally perceived as benign or even beneficial. Depending on the species and local conditions, bivalve molluscs are either grown on the beach, on longlines, or suspended from rafts and harvested by hand or by dredging. In May 2017 a Belgian consortium installed the first of two trial mussel farms on a wind farm in the North Sea . Abalone farming began in the late 1950s and early 1960s in Japan and China. Since

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7392-493: Is highly probable that future developments in this field will rely on microorganisms, but greater funding and further research is needed to overcome the lack of knowledge in this field. Microalgae , also referred to as phytoplankton , microphytes , or planktonic algae , constitute the majority of cultivated algae . Macroalgae commonly known as seaweed also have many commercial and industrial uses, but due to their size and specific requirements, they are not easily cultivated on

7568-614: Is keeping them in a wall. Here the use of plywood is hidden by sinking the aquarium inside the wall. Putting insulation between the two helps with the insulation of a heated tank. Objects used for aquariums include: coffee tables, sinks, and even toilets. Another such example is the MacQuarium , an aquarium made from the shell of an Apple Macintosh computer . In recent years, elaborate custom-designed home aquariums costing hundreds of thousands of dollars have become status symbols—according to The New York Times , "among people of means,

7744-467: Is lower than in a monoculture over a short-term period. Fish tank An aquarium ( pl. : aquariums or aquaria ) is a vivarium of any size having at least one transparent side in which aquatic plants or animals are kept and displayed. Fishkeepers use aquaria to keep fish , invertebrates , amphibians , aquatic reptiles , such as turtles , and aquatic plants . The term aquarium , coined by English naturalist Philip Henry Gosse , combines

7920-415: Is made of modified Golgi membranes containing viral-specific polypeptides, including hemagglutinin . Infection with either variola major virus or variola minor virus confers immunity against the other. The more common, infectious form of the disease was caused by the variola major virus strain, known for its significantly higher mortality rate compared to its counterpart, variola minor. Variola major had

8096-417: Is most often addressed through two filtration solutions: Activated carbon filters absorb nitrogen compounds and other toxins , while biological filters provide a medium designed to enhance bacterial colonization . Activated carbon and other substances, such as ammonia absorbing resins, stop working when their pores fill, so these components have to be replaced regularly. Smallpox Smallpox

8272-497: Is not easily derived due to lack of data. Another recent issue following the banning in 2008 of organotins by the International Maritime Organization is the need to find environmentally friendly, but still effective, compounds with antifouling effects. Many new natural compounds are discovered every year, but producing them on a large enough scale for commercial purposes is almost impossible. It

8448-471: Is not transparent. Reinforced concrete is used for aquaria where weight and space are not factors. Concrete must be coated with a waterproof layer to prevent the water from breaking down the concrete, as well as preventing contamination of the water by the concrete. Plywood can also be used when building aquaria. The benefits of using plywood include: lower construction costs, less weight, and better insulation. A popular positioning choice for plywood aquaria

8624-478: Is only a portion of the complete cycle: nitrogen must be added to the system (usually through food provided to the tank inhabitants), and nitrates accumulate in the water at the end of the process, or become bound in the biomass of plants. The aquarium keeper must remove water once nitrate concentrations grow, or remove plants which have grown from the nitrates. Hobbyist aquaria often do not have sufficient bacteria populations to adequately denitrify waste. This problem

8800-588: Is produced in Asia, in particular in China and Thailand. The other 25% is produced mainly in Latin America, where Brazil is the largest producer. Thailand is the largest exporter. Shrimp farming has changed from its traditional, small-scale form in Southeast Asia into a global industry. Technological advances have led to ever higher densities per unit area, and broodstock is shipped worldwide. Virtually all farmed shrimp are penaeids (i.e., shrimp of

8976-493: Is rapidly followed by the development of petechiae and bleeding in the skin, conjunctiva and mucous membranes. Death often occurs suddenly between the fifth and seventh days of illness, when only a few insignificant skin lesions are present. Some people survive a few days longer, during which time the skin detaches and fluid accumulates under it, rupturing at the slightest injury. People are usually conscious until death or shortly before. Autopsy reveals petechiae and bleeding in

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9152-462: Is seeded with young abalone from an onshore hatchery. The abalone feed on seaweed that has grown naturally on the habitats, with the ecosystem enrichment of the bay also resulting in growing numbers of dhufish, pink snapper, wrasse, and Samson fish, among other species. Brad Adams, from the company, has emphasised the similarity to wild abalone and the difference from shore-based aquaculture. "We're not aquaculture, we're ranching, because once they're in

9328-518: Is the most basic measure of water conditions. An aquarium may have freshwater (salinity below 500 parts per million), simulating a lake or river environment; brackish water (a salt level of 500 to 30,000 PPM), simulating environments lying between fresh and salt, such as estuaries ; and salt water or seawater (a salt level of 30,000 to 40,000 PPM), simulating an ocean environment. Rarely, higher salt concentrations are maintained in specialized tanks for raising brine organisms. Saltwater

9504-492: Is the practice of cultivating and harvesting seaweed . In its simplest form farmers gather from natural beds, while at the other extreme farmers fully control the crop's life cycle . The seven most cultivated taxa are Eucheuma spp., Kappaphycus alvarezii , Gracilaria spp., Saccharina japonica , Undaria pinnatifida , Pyropia spp., and Sargassum fusiforme . Eucheuma and K. alvarezii are attractive for carrageenan (a gelling agent ); Gracilaria

9680-415: Is to have very small aquariums, termed mini aquariums (less than 150 litres or 40 gallons) or nano aquariums (less than 75 litres or 20 gallons). These can be either freshwater or saltwater, and are intended to display a tiny but self-contained ecosystem. The typical hobbyist aquarium includes a filtration system, an artificial lighting system, an air diffuser and pump, and a heater or chiller depending on

9856-499: Is toxic to fish in high concentrations. Another type of bacteria (genus Nitrospira ) converts nitrite into nitrate , a less toxic substance. ( Nitrobacter bacteria were previously believed to fill this role. While biologically they could theoretically fill the same niche as Nitrospira , it has recently been found that Nitrobacter are not present in detectable levels in established aquaria, while Nitrospira are plentiful.) However, commercial products sold as kits to "jump start"

10032-453: Is typically fatal. Vaccination does not appear to provide any immunity to either form of hemorrhagic smallpox and some cases even occurred among people that were revaccinated shortly before. It has two forms. The early or fulminant form of hemorrhagic smallpox (referred to as purpura variolosa ) begins with a prodromal phase characterized by a high fever, severe headache, and abdominal pain. The skin becomes dusky and erythematous, and this

10208-541: Is usually alkaline, while the pH ( alkalinity or acidity ) of fresh water varies more. Hardness measures overall dissolved mineral content; hard or soft water may be preferred. Hard water is usually alkaline, while soft water is usually neutral to acidic. Dissolved organic content and dissolved gases content are also important factors. Home aquarists typically use tap water supplied through their local water supply network to fill their tanks. Straight tap water cannot be used in localities that pipe chlorinated water. In

10384-695: The Aquaculture Stewardship Council with the Dutch Sustainable Trade Initiative to manage the global standards and certification programs. After trials in 2012, a commercial "sea ranch" was set up in Flinders Bay , Western Australia, to raise abalone. The ranch is based on an artificial reef made up of 5000 (As of April 2016) separate concrete units called abitats (abalone habitats). The 900 kg abitats can host 400 abalone each. The reef

10560-698: The East India Company stationed in China and another by Clopton Havers . Lady Mary Wortley Montagu observed smallpox inoculation during her stay in the Ottoman Empire , writing detailed accounts of the practice in her letters, and enthusiastically promoted the procedure in England upon her return in 1718. According to Voltaire (1742), the Turks derived their use of inoculation from neighbouring Circassia . Voltaire does not speculate on where

10736-533: The Food and Agriculture Organization (FAO), aquaculture "is understood to mean the farming of aquatic organisms including fish, molluscs, crustaceans and aquatic plants. Farming implies some form of intervention in the rearing process to enhance production, such as regular stocking , feeding , protection from predators, etc. Farming also implies individual or corporate ownership of the stock being cultivated." The reported output from global aquaculture operations in 2019

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10912-771: The Great Exhibition of 1851. In 1853, the aquarium craze was launched in England by Philip Henry Gosse who created and stocked the first public aquarium in the London Zoo which came to be known as the Fish House. Gosse coined the word "aquarium", opting for this term (instead of "aquatic vivarium" or "aqua-vivarium") in 1854 in his book The Aquariums: An Unveiling of the Wonders of the Deep Water . In this book, Gosse primarily discussed saltwater aquaria. In

11088-511: The Latin root aqua , meaning 'water', with the suffix -arium , meaning 'a place for relating to'. The aquarium principle was fully developed in 1850 by the chemist Robert Warington , who explained that plants added to water in a container would give off enough oxygen to support animals, so long as the numbers of animals did not grow too large. The aquarium craze was launched in early Victorian England by Gosse, who created and stocked

11264-490: The Victorian era in the United Kingdom, a common design for the home aquarium was a glass front with the other sides made of wood (made watertight with a pitch coating). The bottom would be made of slate and heated from below. More advanced systems soon began to be introduced, along with tanks of glass in metal frames. During the latter half of the 19th century, a variety of aquarium designs were explored, such as hanging

11440-611: The aquascaping designs of Takashi Amano influencing fishkeepers to treat home aquariums as aesthetically pleasing compositions, rather than simply as a way of displaying fish specimens. In the United States, as of 1996, aquarium keeping is the second-most popular hobby after stamp collecting . In 1999, an estimated 9.6 million US households owned an aquarium. Figures from the 2005/2006 APPMA National Pet Owners Survey report that Americans own approximately 139 million freshwater fish and 9.6 million saltwater fish. Estimates of

11616-422: The common cold : fever of at least 38.3 °C (101 °F), muscle pain , malaise , headache and fatigue. As the digestive tract was commonly involved, nausea, vomiting, and backache often occurred. The early prodromal stage usually lasted 2–4 days. By days 12–15, the first visible lesions – small reddish spots called enanthem – appeared on mucous membranes of the mouth, tongue, palate , and throat, and

11792-406: The ecosystem . Some traditional polyculture systems may, in fact, incorporate a greater diversity of species, occupying several niches , as extensive cultures (low intensity, low management) within the same pond. A working IMTA system can result in greater total production based on mutual benefits to the co-cultured species and improved ecosystem health , even if the production of individual species

11968-511: The family Penaeidae ), and just two species of shrimp, the Pacific white shrimp and the giant tiger prawn , account for about 80% of all farmed shrimp. These industrial monocultures are very susceptible to disease, which has decimated shrimp populations across entire regions. Increasing ecological problems, repeated disease outbreaks, and pressure and criticism from both nongovernmental organizations and consumer countries led to changes in

12144-447: The gravel , or other substrate if the aquarium has one; however some manage to avoid this entirely by keeping it somewhat self-sufficient. A good habit is to remove the water being replaced by "vacuuming" the gravel with suitable implements, as this will eliminate uneaten foods and other residues that settle on the substrate . In many areas tap water is not considered to be safe for fish to live in because it contains chemicals that harm

12320-470: The horsepox virus using publicly available sequence data for horsepox. The researchers argued that their work would be beneficial to creating a safer and more effective vaccine for smallpox, although an effective vaccine is already available. The horsepox virus had previously seemed to have gone extinct, raising concern about potential revival of variola major and causing other scientists to question their motives. Critics found it especially concerning that

12496-481: The nitrogen cycle or be removed by passing through zeolite . Ammonia is also produced through the decomposition of plant and animal matter, including fecal matter and other detritus . Nitrogen waste products become toxic to fish and other aquarium inhabitants at high concentrations. In the wild, the vast amount of water surrounding the fish dilutes ammonia and other waste materials. When fish are put into an aquarium, waste can quickly reach toxic concentrations in

12672-468: The replication of viral DNA. The first set of expressed genes are transcribed by pre-existing viral machinery packaged within the infecting virion. These genes encode the factors necessary for viral DNA synthesis and for transcription of the next set of expressed genes. Unlike most DNA viruses, DNA replication in variola virus and other poxviruses takes place within the cytoplasm of the infected cell. The exact timing of DNA replication after infection of

12848-661: The weight of water (1 kilogram per litre (8.345 lb/U.S. gal; 10.022 lb/imp gal)) and internal water pressure (requiring thick glass siding) of a large aquarium, restrict most home aquaria to a maximum of around 1 cubic metre in volume (1000 L, weighing 1,000 kg or 2,200 lb ). Some aquarists, however, have constructed aquaria of many thousands of litres. Public aquariums and oceanariums designed for exhibition of large species or environments can be dramatically larger than any home aquarium. The Georgia Aquarium , for example, features an individual aquarium of 6,300,000 US gallons (24,000,000 L). A new trend

13024-465: The 1500s. Europe adopted this practice from Asia in the first half of the 18th century. In 1796, Edward Jenner introduced the modern smallpox vaccine. In 1967, the WHO intensified efforts to eliminate the disease. Smallpox is one of two infectious diseases to have been eradicated, the other being rinderpest (a disease of even-toed ungulates ) in 2011. The term "smallpox" was first used in England in

13200-409: The 16th century to distinguish the disease from syphilis , which was then known as the "great pox". Other historical names for the disease include pox, speckled monster, and red plague. The United States and Russia retain samples of variola virus in laboratories, which has sparked debates over safety . There are two forms of the smallpox. Variola major is the severe and most common form, with

13376-429: The 1850s, the aquarium became a fad in the United Kingdom. Tank designs and techniques for maintaining water quality were developed by Warington, later cooperating with Gosse until his critical review of the tank water composition. Edward Edwards developed these glass-fronted aquaria in his 1858 patent for a "dark-water-chamber slope-back tank", with water slowly circulating to a reservoir beneath. Germans soon rivaled

13552-624: The 18th and 19th centuries. Variola virus is large and brick-shaped and is approximately 302 to 350 nanometers by 244 to 270 nm, with a single linear double stranded DNA genome 186 kilobase pairs (kbp) in size and containing a hairpin loop at each end. Four orthopoxviruses cause infection in humans: variola, vaccinia , cowpox , and monkeypox . Variola virus infects only humans in nature, although primates and other animals have been infected in an experimental setting. Vaccinia, cowpox, and monkeypox viruses can infect both humans and other animals in nature. The life cycle of poxviruses

13728-520: The 1960s, metal frames made marine aquaria almost impossible due to corrosion, but the development of tar and silicone sealant allowed the first all-glass aquaria made by Martin Horowitz in Los Angeles, CA. The frames remained, however, though purely for aesthetic reasons. Japan played an increasingly important role in shaping aquarium design in the latter part of the twentieth century, with

13904-428: The 1980s and 1990s. In 2012, the total world production of fisheries was 158 million tonnes , of which aquaculture contributed 66.6 million tonnes, about 42%. The growth rate of worldwide aquaculture has been sustained and rapid, averaging about 8% per year for over 30 years, while the take from wild fisheries has been essentially flat for the last decade. The aquaculture market reached $ 86 billion in 2009. Aquaculture

14080-937: The Agriculture Ministry's Bureau of Fisheries, as saying that China's figures were "basically correct". However, the FAO accepted there were issues with the reliability of China's statistical returns, and for a period treated data from China, including the aquaculture data, apart from the rest of the world. Mariculture is the cultivation of marine organisms in seawater , variously in sheltered coastal waters ("inshore"), open ocean ("offshore"), and on land ("onshore"). Farmed species include algae (from microalgae (such as phytoplankton ) to macroalgae (such as seaweed ); shellfish (such as shrimp ), lobster , oysters ), and clams , and marine finfish . Channel catfish ( Ictalurus punctatus ), hard clams ( Mercenaria mercenaria ) and Atlantic salmon ( Salmo salar ) are prominent in

14256-649: The British in their interest. In 1854, an anonymous author had two articles published about the saltwater aquaria of the United Kingdom: Die Gartenlaube (The Garden House) entitled Der Ocean auf dem Tische (The Ocean on the Table). However, in 1856, Der See im Glase (The Lake in a Glass) was published, discussing freshwater aquaria, which were much easier to maintain in landlocked areas. In 1862 William Alford Lloyd , then bankrupt because of

14432-475: The Caribbean (2%). The contribution of aquaculture to the global production of capture fisheries and aquaculture combined has risen continuously, reaching 46.8 percent in 2016, up from 25.7 percent in 2000. With 5.8 percent annual growth rate during the period 2001–2016, aquaculture continues to grow faster than other major food production sectors, but it no longer has the high annual growth rates experienced in

14608-779: The Circassians derived their technique from, though he reports that the Chinese have practiced it "these hundred years". In 1721, Cotton Mather and colleagues provoked controversy in Boston by inoculating hundreds. After publishing The present method of inoculating for the small-pox in 1767, Dr Thomas Dimsdale was invited to Russia to variolate the Empress Catherine the Great of Russia and her son, Grand Duke Paul , which he successfully did in 1768. In 1796, Edward Jenner ,

14784-411: The U.S. mariculture. Mariculture may consist of raising the organisms on or in artificial enclosures such as in floating netted enclosures for salmon, and on racks or in floating cages for oysters. In the case of enclosed salmon, they are fed by the operators; oysters on racks filter feed on naturally available food. Abalone have been farmed on an artificial reef consuming seaweed which grows naturally on

14960-770: The United States at the CDC in Atlanta, and one at the Vector Institute in Koltsovo, Russia. Research with the remaining virus samples is tightly controlled, and each research proposal must be approved by the WHO and the World Health Assembly (WHA). Most research on poxviruses is performed using the closely related Vaccinia virus as a model organism. Vaccinia virus, which is used to vaccinate for smallpox,

15136-516: The United States, Great Britain, and South Africa in the early 20th century, becoming the dominant form of the disease in those areas and thus rapidly decreasing mortality rates. Along with variola major, the minor form has now been totally eradicated from the globe. The last case of indigenous variola minor was reported in a Somali cook, Ali Maow Maalin, in October 1977, and smallpox was officially declared eradicated worldwide in May 1980. Variola minor

15312-531: The WHO eradication campaign. A genome browser for a complete database of annotated sequences of variola virus and other poxviruses is publicly available through the Viral Bioinformatics Resource Center . The WHO currently bans genetic engineering of the variola virus. However, in 2004, a committee advisory to the WHO voted in favor of allowing editing of the genome of the two remaining samples of variola major virus to add

15488-507: The absence of Guarnieri bodies could not be used to rule out smallpox. The diagnosis of an orthopoxvirus infection can also be made rapidly by electron microscopic examination of pustular fluid or scabs. All orthopoxviruses exhibit identical brick-shaped virions by electron microscopy. If particles with the characteristic morphology of herpesviruses are seen this will eliminate smallpox and other orthopoxvirus infections. Definitive laboratory identification of variola virus involved growing

15664-482: The addition of a commercially available mixture of salts and other minerals. Some aquarists modify water's alkalinity, hardness, or dissolved content of organics and gases, before adding it to their aquaria. This can be accomplished by additives, such as sodium bicarbonate, to raise pH. Some aquarists filter or purify their water through deionization or reverse osmosis prior to using it. In contrast, public aquaria with large water needs often locate themselves near

15840-548: The aquarium on a wall, mounting it as part of a window , or even combining it with a birdcage . Around 1908, the first mechanical aquarium air pump was invented, powered by running water, instead of electricity. The introduction of the air pump into the hobby is considered by several historians of the hobby to be a pivotal moment in its development. Aquaria became more widely popular as houses had an electricity supply after World War I . Electricity allowed artificial lighting, as well as aeration , filtration , and heating of

16016-505: The aquarium's inhabitants. Many aquaria incorporate a hood, containing the lights, to decrease evaporation and prevent fish from leaving the aquarium (and anything else from entering the aquarium). Combined biological and mechanical aquarium filtration systems are common. These either convert ammonia to nitrate (removing nitrogen at the expense of aquatic plants), or to sometimes remove phosphate . Filter media can house microbes that mediate nitrification . Filtration systems are sometimes

16192-491: The aquarium's inhabitants. Water movement can be controlled via aeration from air pumps, powerheads, and careful design of internal water flow (such as location of filtration system points of inflow and outflow). Of primary concern to the aquarist is management of the waste produced by an aquarium's inhabitants. Fish, invertebrates, fungi , and some bacteria excrete nitrogen waste in the form of ammonia (which converts to ammonium , in water) and must then either pass through

16368-547: The aquarium. According to the July issue of The North American Review of the same year, William Stimson may have owned some of the first functional aquaria, and had as many as seven or eight. The first aquarist society in the United States was founded in New York City in 1893, followed by others. The New York Aquarium Journal , first published in October 1876, is considered to be the world's first aquarium magazine. In

16544-460: The behavior and survival of tank inhabitants. An aquarium can be placed on an aquarium stand. Because of the weight of the aquarium, a stand must be strong as well as level. A tank that is not level may distort, leak, or crack. These are often built with cabinets to allow storage, available in many styles to match room decor . Simple metal tank stands are also available. Most aquaria should be placed on polystyrene to cushion any irregularities on

16720-448: The bloodstream in large numbers, a condition known as viremia . This resulted in the second wave of multiplication in the spleen , bone marrow , and lymph nodes. The clinical definition of ordinary smallpox is an illness with acute onset of fever equal to or greater than 38.3 °C (101 °F) followed by a rash characterized by firm, deep-seated vesicles or pustules in the same stage of development without other apparent cause. When

16896-477: The central region of the genome is highly consistent across orthopoxviruses , and the arrangement of genes is consistent across chordopoxviruses. The center of the variola virus genome contains the majority of the essential viral genes, including the genes for structural proteins , DNA replication , transcription , and mRNA synthesis. The ends of the genome vary more across strains and species of orthopoxviruses . These regions contain proteins that modulate

17072-503: The closely related Vaccinia virus . The public availability of the variola virus complete sequence has raised concerns about the possibility of illicit synthesis of infectious virus. Vaccinia , a cousin of the variola virus, was artificially synthesized in 2002 by NIH scientists. They used a previously established method that involved using a recombinant viral genome to create a self-replicating bacterial plasmid that produced viral particles. In 2016, another group synthesized

17248-621: The course of the illness, but this happened most frequently during the first week of the rash when most of the skin lesions were intact. Infectivity waned in 7 to 10 days when scabs formed over the lesions, but the infected person was contagious until the last smallpox scab fell off. Concern about possible use of smallpox for biological warfare led in 2002 to Donald K. Milton's detailed review of existing research on its transmission and of then-current recommendations for controlling its spread. He agreed, citing Rao, Fenner and others, that “careful epidemiologic investigation rarely implicated fomites as

17424-529: The craze in England being over, moved to Grindel Dammthor, Hamburg, to supervise the installation of the circulating system and tanks at the Hamburg Aquarium . During the 1870s, some of the first aquarist societies were appearing in Germany. The United States soon followed. Published in 1858, Henry D. Butler's The Family Aquarium was one of the first books written in the United States solely about

17600-401: The cultivated species are subjected to relatively more naturalistic environments; or on fenced/enclosed sections of open water away from the shore (offshore aquaculture), where the species are either cultured in cages, racks or bags and are exposed to more diverse natural conditions such as water currents (such as ocean currents ), diel vertical migration and nutrient cycles . According to

17776-547: The cultivation of ornamental fish . Particular methods include aquaponics and integrated multi-trophic aquaculture , both of which integrate fish farming and aquatic plant farming. The FAO describes aquaculture as one of the industries most directly affected by climate change and its impacts. Some forms of aquaculture have negative impacts on the environment, such as through nutrient pollution or disease transfer to wild populations. Harvest stagnation in wild fisheries and overexploitation of popular marine species, combined with

17952-438: The decade to 2007. Given the long-term importance of agriculture, to date, only 0.08% of known land plant species and 0.0002% of known land animal species have been domesticated, compared with 0.17% of known marine plant species and 0.13% of known marine animal species. Domestication typically involves about a decade of scientific research. Domesticating aquatic species involves fewer risks to humans than do land animals, which took

18128-442: The demand for farmed fish. However, finding alternative sources of protein and oil for fish feed is necessary so the aquaculture industry can grow sustainably; otherwise, it represents a great risk for the over-exploitation of forage fish. Aquaculture production now exceeds capture fishery production and together the relative GDP contribution has ranged from 0.01 to 10%. Singling out aquaculture's relative contribution to GDP, however,

18304-705: The developmental lifecycle of the main species, the giant river prawn . The global annual production of freshwater prawns (excluding crayfish and crabs ) in 2007 was about 460,000 tonnes , exceeding 1.86 billion dollars. Additionally, China produced about 370,000 tonnes of Chinese river crab . In addition astaciculture is the freshwater farming of crayfish (mostly in the US, Australia, and Europe). Aquacultured shellfish include various oyster , mussel , and clam species. These bivalves are filter and/or deposit feeders, which rely on ambient primary production rather than inputs of fish or other feed. As such, shellfish aquaculture

18480-403: The diagnosis of infection. Chickenpox was commonly confused with smallpox in the immediate post-eradication era. Chickenpox and smallpox could be distinguished by several methods. Unlike smallpox, chickenpox does not usually affect the palms and soles. Additionally, chickenpox pustules are of varying size due to variations in the timing of pustule eruption: smallpox pustules are all very nearly

18656-595: The disease dates to around 1500 BC in Egyptian mummies . The disease historically occurred in outbreaks . It was one of several diseases introduced by the Columbian exchange to the New World , resulting in large swathes of Native Americans dying . In 18th-century Europe, it is estimated that 400,000 people died from the disease per year, and that one-third of all cases of blindness were due to smallpox. Smallpox

18832-479: The disease included fever and vomiting. This was followed by formation of ulcers in the mouth and a skin rash . Over a number of days, the skin rash turned into the characteristic fluid-filled blisters with a dent in the center. The bumps then scabbed over and fell off, leaving scars. The disease was transmitted from one person to another primarily through prolonged face-to-face contact with an infected person or rarely via contaminated objects . Prevention

19008-421: The enclosed environment unless the tank is cycled to remove waste. A well-balanced tank contains organisms that are able to metabolize the waste products of other aquarium residents, recreating a portion of the nitrogen cycle . Bacteria known as nitrifiers (genus Nitrosomonas ) metabolize nitrogen waste. Nitrifying bacteria capture ammonia from the water and metabolize it to produce nitrite . Nitrite

19184-779: The first public aquarium at the London Zoo in 1853, and published the first manual, The Aquarium: An Unveiling of the Wonders of the Deep Sea in 1854. Small aquariums are kept in the home by hobbyists . There are large public aquariums in many cities. Public aquariums keep fish and other aquatic animals in large tanks. A large aquarium may have otters , dolphins , sharks , penguins , seals , and whales . Many aquarium tanks also have plants. An aquarist owns fish or maintains an aquarium, typically constructed of glass or high-strength acrylic . Aquaria with flat walls are known as fish tanks or simply tanks, while those with rounded walls are known as fish bowls . Size can range from

19360-557: The first person to create aquaria for experimenting with aquatic organisms. This experimentation lead to several discoveries, including the first direct evidence that argonauts , a marine cephalopod, create their own shells. In 1836, soon after his invention of the Wardian case , Dr. Nathaniel Bagshaw Ward proposed to use his tanks for tropical animals. In 1841 he did so, though only with aquatic plants and toy fish. However, he soon housed real animals. In 1838, Félix Dujardin noted owning

19536-416: The fish are kept healthy. Daily maintenance consists of checking the fish for signs of stress and disease . Also, aquarists must make sure that the water has a good quality and it is not cloudy or foamy and the temperature of the water is appropriate for the particular species of fish that live in the aquarium. Typical weekly maintenance includes changing around 10–30% or more of the water while cleaning

19712-594: The fish. Tap water from those areas must be treated with a suitable water conditioner, such as a product which removes chlorine and chloramine and neutralizes any heavy metals present. The water conditions must be checked both in the tank and in the replacement water, to make sure they are suitable for the species. The solute content of water is perhaps the most important aspect of water conditions, as total dissolved solids and other constituents dramatically impact basic water chemistry, and therefore how organisms interact with their environment. Salt content, or salinity ,

19888-413: The fisheries and aquaculture primary sector. In 2021, global fish production reached 182 million tonnes, with approximately equal amounts coming from capture (91.2 million tonnes) and aquaculture (90.9 million tonnes). Aquaculture has experienced rapid growth in recent decades, increasing almost sevenfold from 1990 to 2021. China overwhelmingly dominates the world in reported aquaculture output, reporting

20064-408: The genome of vaccinia , a related virus used for vaccination against smallpox. Gene expression of variola virus occurs entirely within the cytoplasm of the host cell , and follows a distinct progression during infection. After entry of an infectious virion into a host cell, synthesis of viral mRNA can be detected within 20 minutes. About half of the viral genome is transcribed prior to

20240-473: The glass panels attached with metal frames and sealed with putty. Metal-framed aquariums were still available until the mid-1960s, when the modern, silicone-sealed style replaced them. Acrylic aquariums first became available to the public in the 1970s. Laminated glass is sometimes used, which combines the advantages of both glass and acrylic. Today, most aquaria consist of glass panes bonded together by 100% silicone sealant, with plastic frames attached to

20416-429: The group was able to recreate viable virus in a short time frame with relatively little cost or effort. Although the WHO bans individual laboratories from synthesizing more than 20% of the genome at a time, and purchases of smallpox genome fragments are monitored and regulated, a group with malicious intentions could compile, from multiple sources, the full synthetic genome necessary to produce viable virus. Smallpox

20592-498: The hosts' immune systems, and are primarily responsible for the variability in virulence across the orthopoxvirus family. These terminal regions in poxviruses are inverted terminal repetitions (ITR) sequences. These sequences are identical but oppositely oriented on either end of the genome, leading to the genome being a continuous loop of DNA. Components of the ITR sequences include an incompletely base paired A/T rich hairpin loop ,

20768-450: The incorporation of species from different trophic or nutritional levels in the same system. This is one potential distinction from the age-old practice of aquatic polyculture , which could simply be the co-culture of different fish species from the same trophic level. In this case, these organisms may all share the same biological and chemical processes, with few synergistic benefits, which could potentially lead to significant shifts in

20944-438: The increased demand for seafood. Aquaculture can be conducted in completely artificial facilities built on land (onshore aquaculture), as in the case of fish tank , ponds , aquaponics or raceways , where the living conditions rely on human control such as water quality (oxygen), feed, temperature. Alternatively, they can be conducted on well-sheltered shallow waters nearshore of a body of water (inshore aquaculture), where

21120-486: The industry in the late 1990s and generally stronger regulations. In 1999, governments, industry representatives, and environmental organizations initiated a program aimed at developing and promoting more sustainable farming practices through the Seafood Watch program. Freshwater prawn farming shares many characteristics with, including many problems with, marine shrimp farming. Unique problems are introduced by

21296-414: The industry. Sea ranching involves raising fish in a hatchery for a brief time and then releasing them into marine waters for further development, whereupon the fish are recaptured when they have matured. Commercial shrimp farming began in the 1970s, and production grew steeply thereafter. Global production reached more than 1.6 million tonnes in 2003, worth about US$ 9 billion. About 75% of farmed shrimp

21472-436: The lesions remained almost flush with the skin at the time when raised vesicles would have formed in the ordinary type. It is unknown why some people developed this type. Historically, it accounted for 5–10% of cases, and most (72%) were children. Malignant smallpox was accompanied by a severe prodromal phase that lasted 3–4 days, prolonged high fever, and severe symptoms of viremia . The prodromal symptoms continued even after

21648-406: The lower respiratory tract] are maintained”. Once inhaled, the variola virus invaded the mucous membranes of the mouth, throat, and respiratory tract. From there, it migrated to regional lymph nodes and began to multiply. In the initial growth phase, the virus seemed to move from cell to cell, but by around the 12th day, widespread lysis of infected cells occurred and the virus could be found in

21824-408: The malignant and hemorrhagic forms were usually fatal. The modified form was almost never fatal. In early hemorrhagic cases, hemorrhages occurred before any skin lesions developed. The incubation period between contraction and the first obvious symptoms of the disease was 7–14 days. At least 90% of smallpox cases among unvaccinated persons were of the ordinary type. In this form of the disease, by

22000-540: The market. In 2009, researchers in Australia managed for the first time to coax southern bluefin tuna to breed in landlocked tanks. Southern bluefin tuna are also caught in the wild and fattened in grow-out sea cages in southern Spencer Gulf , South Australia . A similar process is used in the salmon-farming section of this industry; juveniles are taken from hatcheries and a variety of methods are used to aid them in their maturation. For example, as stated above, some of

22176-549: The mid-1990s, this industry has become increasingly successful. Overfishing and poaching have reduced wild populations to the extent that farmed abalone now supplies most abalone meat. Sustainably farmed molluscs can be certified by Seafood Watch and other organizations, including the World Wildlife Fund (WWF). WWF initiated the "Aquaculture Dialogues" in 2004 to develop measurable and performance-based standards for responsibly farmed seafood. In 2009, WWF co-founded

22352-678: The most complex component of home aquaria. Aquarium heaters combine a heating element with a thermostat , allowing the aquarist to regulate water temperature at a level above that of the surrounding air, whereas coolers and chillers (refrigeration devices) are for use anywhere, such as cold water aquaria, where the ambient room temperature is above the desired tank temperature. Thermometers used include glass alcohol thermometers, adhesive external plastic strip thermometers , and battery-powered LCD thermometers. In addition, some aquarists use air pumps attached to airstones or water pumps to increase water circulation and supply adequate gas exchange at

22528-432: The most important fish species in the industry, salmon, can be grown using a cage system. This is done by having netted cages, preferably in open water that has a strong flow, and feeding the salmon a special food mixture that aids their growth. This process allows for year-round growth of the fish, thus a higher harvest during the correct seasons. An additional method, known sometimes as sea ranching, has also been used within

22704-716: The most popular biotopes are the freshwater habitats of the Amazon River , the Rio Negro River, the African rift lake environments of Lake Malawi and Lake Tanganyika , and saltwater coral reefs of Australia , the Red Sea , and the Caribbean Sea . The fish, plants, substrate, rocks, wood, coral, and any other component of the display should completely match that of the local natural environment. It can be

22880-539: The nitrogen cycle often still contain Nitrobacter . Aquatic plants also eliminate nitrogen waste by metabolizing ammonia and nitrate. When plants metabolize nitrogen compounds, they remove nitrogen from the water by using it to build biomass that decays more slowly than ammonia-driven plankton already dissolved in the water. Some hobbyists also use "anoxic filtration," which relies on bacteria that live in low-oxygen environments. The nitrogen cycle in an aquarium

23056-431: The numbers of fish kept in aquaria in Germany suggest at least 36 million. The hobby has the strongest following in Europe, Asia, and North America. In the United States, 40% of aquarists maintain two or more tanks. Over time, there has been an increasing appreciation of the usefulness of access to an aquarium to provide potential stress reduction and improvement of mood in people observing aquatic life. According to

23232-404: The onset of the rash. The rash on the mucous membranes ( enanthem ) was extensive. Skin lesions matured slowly, were typically confluent or semi-confluent, and by the seventh or eighth day, they were flat and appeared to be buried in the skin. Unlike ordinary-type smallpox, the vesicles contained little fluid, were soft and velvety to the touch, and may have contained hemorrhages. Malignant smallpox

23408-429: The oral, nasal, or pharyngeal mucosa of an infected person. It was transmitted from one person to another primarily through prolonged face-to-face contact with an infected person. Some infections of laundry workers with smallpox after handling contaminated bedding suggested that smallpox could be spread through direct contact with contaminated objects ( fomites ), but this was found to be rare. Also rarely, smallpox

23584-523: The outer layers of skin from the underlying flesh. Patients with confluent smallpox often remained ill even after scabs had formed over all the lesions. In one case series, the case-fatality rate in confluent smallpox was 62%. Referring to the character of the eruption and the rapidity of its development, modified smallpox occurred mostly in previously vaccinated people. It was rare in unvaccinated people, with one case study showing 1–2% of modified cases compared to around 25% in vaccinated people. In this form,

23760-410: The past, it was possible to "condition" the water by simply letting the water stand for a day or two, which allows the chlorine time to dissipate. However, chloramine is now used more often and does not leave the water as readily. Water conditioners formulated to remove chlorine or chloramine are often all that is needed to make the water ready for aquarium use. Brackish or saltwater aquaria require

23936-535: The person was infected with variola virus, a severe infection could result, and the person could transmit smallpox to others. Variolation had a 0.5–2 percent mortality rate, considerably less than the 20–30 percent mortality rate of smallpox. Two reports on the Chinese practice of inoculation were received by the Royal Society in London in 1700; one by Dr. Martin Lister who received a report by an employee of

24112-497: The practice arrived in Europe. The idea that inoculation originated in India has been challenged, as few of the ancient Sanskrit medical texts described the process of inoculation. Accounts of inoculation against smallpox in China can be found as early as the late 10th century, and the procedure was widely practiced by the 16th century, during the Ming dynasty . If successful, inoculation produced lasting immunity to smallpox. Because

24288-428: The price difference tends to disappear. Acrylic aquaria are now the primary competitor with glass. Prior to the invention of UV stabilization , early acrylic aquaria discolored over time with exposure to light; this is no longer the case. Acrylic is generally stronger than glass, weighs less, and provides a certain amount of temperature insulation. In colder climates or environments, it is easier to achieve and maintain

24464-491: The prodromal illness still occurred but may have been less severe than in the ordinary type. There was usually no fever during the evolution of the rash. The skin lesions tended to be fewer and evolved more quickly, were more superficial, and may not have shown the uniform characteristic of more typical smallpox. Modified smallpox was rarely, if ever, fatal. This form of variola major was more easily confused with chickenpox . In malignant-type smallpox (also called flat smallpox)

24640-569: The reef units. Integrated multi-trophic aquaculture (IMTA) is a practice in which the byproducts (wastes) from one species are recycled to become inputs ( fertilizers , food ) for another. Fed aquaculture (for example, fish , shrimp ) is combined with inorganic extractive and organic extractive (for example, shellfish ) aquaculture to create balanced systems for environmental sustainability (biomitigation), economic stability (product diversification and risk reduction) and social acceptability (better management practices). "Multi-trophic" refers to

24816-578: The reported output from global aquaculture operations was over 120 million tonnes valued at US$ 274 billion and by 2022 it had reached 130.9 million tonnes, valued at USD 312.8 billion. For the first time, aquaculture surpassed capture fisheries in aquatic animal production with 94.4 million tonnes, representing 51 percent of the world total and a record 57 percent of the production destined for human consumption. In 2022 most aquaculture workers were in Asia (95%), followed by Africa (3%) and Latin America and

24992-532: The research of having an aquarium is many health benefits like reduce stress, blood pressure and heart rate improvement, better quality sleep , reduce anxiety and pain , therapy of excited children, Alzheimer's therapy and improve productivity . The first modern aquarium made of glass was developed in the 19th century by Robert Warrington. During the Victorian age , glass aquariums commonly had slate or steel bottoms, which allowed them to be heated underneath by an open-flame heat source. These aquariums had

25168-454: The same size since the viral effect progresses more uniformly. A variety of laboratory methods were available for detecting chickenpox in the evaluation of suspected smallpox cases. The earliest procedure used to prevent smallpox was inoculation with variola minor virus (a method later known as variolation after the introduction of smallpox vaccine to avoid possible confusion), which likely occurred in India, Africa, and China well before

25344-479: The second day of the rash the macules had become raised papules . By the third or fourth day, the papules had filled with an opalescent fluid to become vesicles . This fluid became opaque and turbid within 24–48 hours, resulting in pustules . By the sixth or seventh day, all the skin lesions had become pustules. Between seven and ten days the pustules had matured and reached their maximum size. The pustules were sharply raised, typically round, tense, and firm to

25520-491: The separation of variola virus from Taterapox (an Orthopoxvirus of some African rodents including gerbils ) at 3,000 to 4,000 years ago. This is consistent with archaeological and historical evidence regarding the appearance of smallpox as a human disease which suggests a relatively recent origin. If the mutation rate is assumed to be similar to that of the herpesviruses , the divergence date of variola virus from Taterapox has been estimated to be 50,000 years ago. While this

25696-486: The shape of modern fish bowls. Leonhard Baldner , who wrote Vogel-, Fisch- und Tierbuch (Bird, Fish, and Animal Book) in 1666, maintained weather loaches and newts . It is sometimes held that the aquarium was invented by the Romans, who are said to have kept sea barbels in marble-and-glass tanks, but scholars doubt the veracity of this. In 1832, Jeanne Villepreux-Power , a pioneering French marine biologist, became

25872-520: The spleen, kidney, serous membranes , skeletal muscles, pericardium , liver, gonads and bladder. Historically, this condition was frequently misdiagnosed, with the correct diagnosis made only at autopsy. This form is more likely to occur in pregnant women than in the general population (approximately 16% of cases in unvaccinated pregnant women were early hemorrhagic smallpox, versus roughly 1% in nonpregnant women and adult males). The case fatality rate of early hemorrhagic smallpox approaches 100%. There

26048-399: The tank itself. The tank has no sharp angles around its sides and keeps the housed animals away from plumbing. Water moving into the tank gives a gentle flow that keeps the inhabitants suspended. Water leaves the tank through a screen which prevents animals from being drawn into the pump intake or overflow line. There are several types of kreisel tanks. In a true kreisel, a circular tank has

26224-425: The temperature fell to near-normal. These lesions rapidly enlarged and ruptured, releasing large amounts of virus into the saliva. Variola virus tended to attack skin cells, causing the characteristic pimples, or macules , associated with the disease. A rash developed on the skin 24 to 48 hours after lesions on the mucous membranes appeared. Typically the macules first appeared on the forehead, then rapidly spread to

26400-451: The total and 53 percent if non-food uses (including reduction to fishmeal and fish oil) are excluded. With capture fishery production relatively static since the late 1980s, aquaculture has been responsible for the continuing growth in the supply of fish for human consumption. Global aquaculture production (including aquatic plants) in 2016 was 110.2 million tonnes, with the first-sale value estimated at US$ 244 billion. Three years later, in 2019

26576-411: The touch. The pustules were deeply embedded in the dermis, giving them the feel of a small bead in the skin. Fluid slowly leaked from the pustules, and by the end of the second week, the pustules had deflated and began to dry up, forming crusts or scabs. By day 16–20 scabs had formed over all of the lesions, which had started to flake off, leaving depigmented scars. Ordinary smallpox generally produced

26752-579: The underlying surface or the bottom of the tank itself that may cause cracks. However, some tanks have an underframe making this unnecessary. Another important consideration for aquariums is their electrical usage. Water is expensive to keep heated, along with the lights that many aquariums, especially those with live plants have. New aquarists should also pay close attention to their electrical setup for their aquarium, taking care to set up power connections with drip loops to prevent water from getting to outlets. Large volumes of water enable more stability in

26928-580: The upper and lower edges for decoration. The glass aquarium is standard for sizes up to about 1,000 litres (260 US gal; 220 imp gal). However, glass is brittle and has very little give before fracturing, though generally the sealant fails first. Aquaria are made in a variety of shapes, such as cuboid , hexagonal , angled to fit in a corner (L-shaped), and bow-front (the front side curves outwards). Fish bowls are generally either made of plastic or glass, and are either spherical or some other round configuration in shape. Glass aquaria have been

27104-475: The vesicular stage. Hemorrhages in the mucous membranes appear to occur less often than in the early hemorrhagic form. Sometimes the rash forms pustules which bleed at the base and then undergo the same process as in ordinary smallpox. This form of the disease is characterized by a decrease in all of the elements of the coagulation cascade and an increase in circulating antithrombin . This form of smallpox occurs anywhere from 3% to 25% of fatal cases, depending on

27280-439: The virulence of the smallpox strain. Most people with the late-stage form die within eight to 10 days of illness. Among the few who recover, the hemorrhagic lesions gradually disappear after a long period of convalescence. The case fatality rate for late hemorrhagic smallpox is around 90–95%. Pregnant women are slightly more likely to experience this form of the disease, though not as much as early hemorrhagic smallpox. Smallpox

27456-442: The virus on chorioallantoic membrane (part of a chicken embryo ) and examining the resulting pock lesions under defined temperature conditions. Strains were characterized by polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP) analysis. Serologic tests and enzyme linked immunosorbent assays (ELISA), which measured variola virus-specific immunoglobulin and antigen were also developed to assist in

27632-400: The water surface. Wave-making devices have also been constructed to provide wave action. An aquarium's physical characteristics form another aspect of aquarium design. Size, lighting conditions, density of floating and rooted plants, placement of bog-wood , creation of caves or overhangs, type of substrate , and other factors (including an aquarium's positioning within a room) can all affect

27808-591: The water they look after themselves." Other groups include aquatic reptiles, amphibians, and miscellaneous invertebrates, such as echinoderms and jellyfish . They are separately graphed at the top right of this section, since they do not contribute enough volume to show clearly on the main graph. Commercially harvested echinoderms include sea cucumbers and sea urchins . In China, sea cucumbers are farmed in artificial ponds as large as 400 hectares (1,000 acres). Global fish production peaked at about 171 million tonnes in 2016, with aquaculture representing 47 percent of

27984-611: The water. Initially, amateur aquarists kept native fish (with the exception of goldfish); the availability of exotic species from overseas further increased the popularity of the aquarium. Jugs made from a variety of materials were used to import fish from overseas, with a bicycle foot pump for aeration. Plastic shipping bags were introduced in the 1950s, making it easier to ship fish. The eventual availability of air freight allowed fish to be successfully imported from distant regions. Popular publications started by Herbert R. Axelrod influenced many more hobbyists to start keeping fish. In

28160-554: The whole face, proximal portions of extremities, the trunk, and lastly to distal portions of extremities. The process took no more than 24 to 36 hours, after which no new lesions appeared. At this point, variola major disease could take several very different courses, which resulted in four types of smallpox disease based on the Rao classification: ordinary, modified, malignant (or flat), and hemorrhagic smallpox. Historically, ordinary smallpox had an overall fatality rate of about 30%, and

28336-525: The wild for recreational fishing or to supplement a species' natural numbers is generally referred to as a fish hatchery . Worldwide, the most important fish species used in fish farming are, in order, carp , salmon , tilapia , and catfish . In the Mediterranean, young bluefin tuna are netted at sea and towed slowly towards the shore. They are then interned in offshore pens (sometimes made from floating HDPE pipe) where they are further grown for

28512-409: The wild. Concerned about the impact of growing demand for seafood on the world's oceans, prominent ocean explorer Jacques Cousteau wrote in 1973: "With earth's burgeoning human populations to feed, we must turn to the sea with new understanding and new technology." About 430 (97%) of the species cultured as of 2007 were domesticated during the 20th and 21st centuries, of which an estimated 106 came in

28688-421: Was achieved mainly through the smallpox vaccine . Once the disease had developed, certain antiviral medications could potentially have helped, but such medications did not become available until after the disease was eradicated. The risk of death was about 30%, with higher rates among babies. Often, those who survived had extensive scarring of their skin, and some were left blind. The earliest evidence of

28864-431: Was also called white pox, kaffir pox, Cuban itch, West Indian pox, milk pox, and pseudovariola. The genome of variola major virus is about 186,000 base pairs in length. It is made from linear double stranded DNA and contains the coding sequence for about 200 genes . The genes are usually not overlapping and typically occur in blocks that point towards the closer terminal region of the genome. The coding sequence of

29040-477: Was an infectious disease caused by variola virus (often called smallpox virus), which belongs to the genus Orthopoxvirus . The last naturally occurring case was diagnosed in October 1977, and the World Health Organization (WHO) certified the global eradication of the disease in 1980, making smallpox the only human disease to have been eradicated to date. The initial symptoms of

29216-505: Was fully developed by Warington, explaining that plants added to water in a container would give off enough oxygen to support animals, so long as their numbers do not grow too large. He published his findings in 1850 in the Chemical Society's journal . The keeping of fish in an aquarium became a popular hobby and spread quickly. In the United Kingdom, it became popular after ornate aquaria in cast-iron frames were featured at

29392-428: Was highly contagious, but generally spread more slowly and less widely than some other viral diseases, perhaps because transmission required close contact and occurred after the onset of the rash. The overall rate of infection was also affected by the short duration of the infectious stage. In temperate areas, the number of smallpox infections was highest during the winter and spring. In tropical areas, seasonal variation

29568-442: Was less evident and the disease was present throughout the year. Age distribution of smallpox infections depended on acquired immunity . Vaccination immunity declined over time and was probably lost within thirty years. Smallpox was not known to be transmitted by insects or animals and there was no asymptomatic carrier state. Transmission occurred through inhalation of airborne variola virus, usually droplets expressed from

29744-404: Was marked by a fever that occurred after the usual incubation period and could be confirmed only by antibody studies or, rarely, by viral culture . In addition, there were two very rare and fulminating types of smallpox, the malignant (flat) and hemorrhagic forms, which were usually fatal. The initial symptoms were similar to other viral diseases that are still extant, such as influenza and

29920-421: Was nearly always fatal and death usually occurred between the 8th and 12th day of illness. Often, a day or two before death, the lesions turned ashen gray, which, along with abdominal distension, was a bad prognostic sign. This form is thought to be caused by deficient cell-mediated immunity to smallpox. If the person recovered, the lesions gradually faded and did not form scars or scabs. Hemorrhagic smallpox

30096-652: Was over 120 million tonnes valued at US$ 274 billion, by 2022, it had risen to 130.9 million tonnes, valued at USD 312.8 billion. However, there are issues with the reliability of the reported figures. Further, in current aquaculture practice, products from several kilograms of wild fish are used to produce one kilogram of a piscivorous fish like salmon . Plant and insect-based feeds are also being developed to help reduce wild fish been used for aquaculture feed. Particular kinds of aquaculture include fish farming , shrimp farming , oyster farming , mariculture, pisciculture , algaculture (such as seaweed farming ), and

30272-453: Was over 35 million tonnes. North America produced some 23,000 tonnes of wet seaweed. Alaska, Maine, France, and Norway each more than doubled their seaweed production since 2018 . As of 2019, seaweed represented 30% of marine aquaculture. The farming of fish is the most common form of aquaculture. It involves raising fish commercially in tanks, fish ponds , or ocean enclosures, usually for food. A facility that releases juvenile fish into

30448-430: Was really shrinking annually by 350,000 tonnes. Watson and Pauly suggested this may have been related to Chinese policies where state entities that monitored the economy were also tasked with increasing output. Also, until more recently, the promotion of Chinese officials was based on production increases from their own areas. China disputed this claim. The official Xinhua News Agency quoted Yang Jian, director general of

30624-440: Was spread by virus carried in the air in enclosed settings such as buildings, buses, and trains. The virus can cross the placenta , but the incidence of congenital smallpox was relatively low. Smallpox was not notably infectious in the prodromal period and viral shedding was usually delayed until the appearance of the rash, which was often accompanied by lesions in the mouth and pharynx. The virus can be transmitted throughout

30800-404: Was the primary cause of smallpox outbreaks across Asia and most of Africa. Meanwhile, variola minor was more commonly found in regions of Europe, North America, South America, and certain parts of Africa. Variola minor virus, also called alastrim, was a less common form of the virus, and much less deadly. Although variola minor had the same incubation period and pathogenetic stages as smallpox, it

30976-516: Was the variola major strains (the more clinically severe form of smallpox) which spread from Asia between 400 and 1,600 years ago. A second clade included both alastrim (a phenotypically mild smallpox) described from the American continents and isolates from West Africa which diverged from an ancestral strain between 1,400 and 6,300 years before present. This clade further diverged into two subclades at least 800 years ago. A second estimate has placed

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