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Taura Syndrome
Taura syndrome (TS) is one of the more devastating diseases affecting the shrimp farming industry worldwide. It was first described in Ecuador during the summer of 1992. In March 1993, it returned as a major epidemic and was the object of extensive media coverage. Retrospective studies have suggested a case of Taura syndrome might have occurred on a shrimp farm in Colombia as early as 1990 and the virus was already present in Ecuador in mid-1991. Between 1992 and 1997, the disease spread to all major regions of the Americas where whiteleg shrimp (''Litopenaeus vannamei'') is cultured. The economic impact of TS in the Americas during that period might have exceeded US$2 billion by some estimates. Overview The 1992 Ecuadorian TS epidemic occurred concurrently with an outbreak of black leaf wilt disease in banana plantations. The outbreak of black leaf disease led to an increase in fungicide usage within the Taura River basin district near the city of Guayaquil. The fungicides pr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shrimp Farming
Shrimp farming is an aquaculture business that exists in either a marine or freshwater environment, producing shrimp or prawns (crustaceans of the groups Caridea or Dendrobranchiata) for human consumption. Marine Commercial marine shrimp farming began in the 1970s, and production grew steeply, particularly to match the market demands of the United States, Japan, and Western Europe. The total global production of farmed shrimp reached more than 2.1 million tonnes in 1991, representing a value of nearly US$9 billion. About 30% of farmed shrimp is produced in Asia, particularly in China and Indonesia. The other 54.1% is produced mainly in Latin America, where Brazil, Ecuador, and Mexico are the largest producers. The largest exporting nation is Indonesia. Shrimp farming has changed from traditional, small-scale businesses in Southeast Asia into a global industry. Technological advances have led to growing shrimp at ever higher densities, and broodstock is shipped worldwide. Virtua ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
BASF
BASF Societas Europaea, SE () is a German multinational corporation, multinational chemical company and the List of largest chemical producers, largest chemical producer in the world. Its headquarters is located in Ludwigshafen, Germany. The BASF Group comprises subsidiary, subsidiaries and joint ventures in more than 80 countries and operates six integrated production sites and 390 other production sites in Europe, Asia, Australia, the Americas and Africa. BASF has customers in over 190 countries and supplies products to a wide variety of industries. Despite its size and global presence, BASF has received relatively little public attention since it abandoned the manufacture and sale of BASF-branded consumer electronics products in the 1990s. At the end of 2019, the company employed 117,628 people, with over 54,000 in Germany. , BASF posted sales of €59.3 billion and income from operations before special items of about €4.5 billion. Between 1990 and 2005, the co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Messenger RNA
In molecular biology, messenger ribonucleic acid (mRNA) is a single-stranded molecule of RNA that corresponds to the genetic sequence of a gene, and is read by a ribosome in the process of synthesizing a protein. mRNA is created during the process of transcription, where an enzyme (RNA polymerase) converts the gene into primary transcript mRNA (also known as pre-mRNA). This pre-mRNA usually still contains introns, regions that will not go on to code for the final amino acid sequence. These are removed in the process of RNA splicing, leaving only exons, regions that will encode the protein. This exon sequence constitutes mature mRNA. Mature mRNA is then read by the ribosome, and, utilising amino acids carried by transfer RNA (tRNA), the ribosome creates the protein. This process is known as translation. All of these processes form part of the central dogma of molecular biology, which describes the flow of genetic information in a biological system. As in DNA, genetic inf ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nucleotide
Nucleotides are organic molecules consisting of a nucleoside and a phosphate. They serve as monomeric units of the nucleic acid polymers – deoxyribonucleic acid (DNA) and ribonucleic acid (RNA), both of which are essential biomolecules within all life-forms on Earth. Nucleotides are obtained in the diet and are also synthesized from common nutrients by the liver. Nucleotides are composed of three subunit molecules: a nucleobase, a five-carbon sugar (ribose or deoxyribose), and a phosphate group consisting of one to three phosphates. The four nucleobases in DNA are guanine, adenine, cytosine and thymine; in RNA, uracil is used in place of thymine. Nucleotides also play a central role in metabolism at a fundamental, cellular level. They provide chemical energy—in the form of the nucleoside triphosphates, adenosine triphosphate (ATP), guanosine triphosphate (GTP), cytidine triphosphate (CTP) and uridine triphosphate (UTP)—throughout the cell for the many cellular func ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Positive-sense
In molecular biology and genetics, the sense of a nucleic acid molecule, particularly of a strand of DNA or RNA, refers to the nature of the roles of the strand and its complement in specifying a sequence of amino acids. Depending on the context, sense may have slightly different meanings. For example, negative-sense strand of DNA is equivalent to the template strand, whereas the positive-sense strand is the non-template strand whose nucleotide sequence is equivalent to the sequence of the mRNA transcript. DNA sense Because of the complementary nature of base-pairing between nucleic acid polymers, a double-stranded DNA molecule will be composed of two strands with sequences that are reverse complements of each other. To help molecular biologists specifically identify each strand individually, the two strands are usually differentiated as the "sense" strand and the "antisense" strand. An individual strand of DNA is referred to as positive-sense (also positive (+) or simply sense) i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Buoyant Density
Buoyancy (), or upthrust, is an upward force exerted by a fluid that opposes the weight of a partially or fully immersed object. In a column of fluid, pressure increases with depth as a result of the weight of the overlying fluid. Thus the pressure at the bottom of a column of fluid is greater than at the top of the column. Similarly, the pressure at the bottom of an object submerged in a fluid is greater than at the top of the object. The pressure difference results in a net upward force on the object. The magnitude of the force is proportional to the pressure difference, and (as explained by Archimedes' principle) is equivalent to the weight of the fluid that would otherwise occupy the submerged volume of the object, i.e. the displaced fluid. For this reason, an object whose average density is greater than that of the fluid in which it is submerged tends to sink. If the object is less dense than the liquid, the force can keep the object afloat. This can occur only in a non ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Icosahedral
In geometry, an icosahedron ( or ) is a polyhedron with 20 faces. The name comes and . The plural can be either "icosahedra" () or "icosahedrons". There are infinitely many non- similar shapes of icosahedra, some of them being more symmetrical than others. The best known is the (convex, non- stellated) regular icosahedron—one of the Platonic solids—whose faces are 20 equilateral triangles. Regular icosahedra There are two objects, one convex and one nonconvex, that can both be called regular icosahedra. Each has 30 edges and 20 equilateral triangle faces with five meeting at each of its twelve vertices. Both have icosahedral symmetry. The term "regular icosahedron" generally refers to the convex variety, while the nonconvex form is called a ''great icosahedron''. Convex regular icosahedron The convex regular icosahedron is usually referred to simply as the ''regular icosahedron'', one of the five regular Platonic solids, and is represented by its Schläfli symbol , co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nanometre
330px, Different lengths as in respect to the molecular scale. The nanometre (international spelling as used by the International Bureau of Weights and Measures; SI symbol: nm) or nanometer (American and British English spelling differences#-re, -er, American spelling) is a units of measurement, unit of length in the International System of Units (SI), equal to one billionth (short scale) of a metre () and to 1000 picometres. One nanometre can be expressed in scientific notation as , and as metres. History The nanometre was formerly known as the millimicrometre – or, more commonly, the millimicron for short – since it is of a micron (micrometre), and was often denoted by the symbol mμ or (more rarely and confusingly, since it logically should refer to a ''millionth'' of a micron) as μμ. Etymology The name combines the SI prefix ''nano-'' (from the Ancient Greek , ', "dwarf") with the parent unit name ''metre'' (from Greek , ', "unit of measurement"). ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aparavirus
''Aparavirus'' is a genus of viruses in the order ''Picornavirales'', in the family ''Dicistroviridae''. Invertebrates, honeybee, and bumblebees serve as natural hosts. There are six species in this genus. Diseases associated with this genus include: ABPV: paralysis. This virus plays a role in sudden collapse of honey bee colonies infested with the parasitic mite varroa destructor. Taxonomy The genus contains the following species: *''Acute bee paralysis virus'' *''Israeli acute paralysis virus'' *''Kashmir bee virus Diseases of the honey bee or abnormal hive conditions include: Pests and parasites ''Varroa'' mites ''Varroa destructor'' and ''V. jacobsoni'' are parasitic mites that feed on the fat bodies of adult, pupal and larval bees. When the hive ...'' *'' Mud crab virus'' *'' Solenopsis invicta virus-1'' *'' Taura syndrome virus'' Structure Viruses in ''Aparavirus'' are non-enveloped, with icosahedral geometries, and T=pseudo3 symmetry. The diameter is around 30 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cripavirus
''Cripavirus'' is a genus of viruses in the order ''Picornavirales'', in the family ''Dicistroviridae''. Invertebrates serve as natural hosts. There are four species in this genus. Diseases associated with this genus include: DCV: increased reproductive potential; extremely pathogenic when injected with high associated mortality; CrPV: paralysis and death. These viruses can produce proteins directly from their RNA genome upon entering a cell; and therefore, does not require an RNA polymerase packaged in with it, as this may be produced from the genome after entering the cell.International Committee on the Taxonomy of Viruses The name of the cripavirus family originates from its most famous member the Cricket Paralysis Virus. Which was made famous by its rather unusual < ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dicistroviridae
''Dicistroviridae'' is a family of viruses in the order ''Picornavirales''. Invertebrates, including aphids, leafhoppers, flies, bees, ants, and silkworms, serve as natural hosts. There are 15 species in this family, assigned to three genera. Diseases associated with this family include: DCV: increased reproductive potential. extremely pathogenic when injected with high associated mortality. CrPV: paralysis and death. Taxonomy Although many dicistroviruses were initially placed in the ''Picornaviridae'', they have since been reclassified into their own family. The name (Dicistro) is derived from the characteristic dicistronic arrangement of the genome. This family is a member of the Order ''Picornavirales'' (along with the families ''Iflaviridae'', ''Picornaviridae'', and ''Secoviridae'' and '' Marnaviridae''). Within this order, the gene order is the gene order of the nonstructural proteins Hel(helicase)-Pro(protease)-RdRp(polymerase). The ''Dicistroviridae'' can be disting ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Picornaviridae
Picornaviruses are a group of related nonenveloped RNA viruses which infect vertebrates including fish, mammals, and birds. They are viruses that represent a large family of small, positive-sense, single-stranded RNA viruses with a 30 nm icosahedral capsid. The viruses in this family can cause a range of diseases including the common cold, poliomyelitis, meningitis, hepatitis, and paralysis. Picornaviruses constitute the family ''Picornaviridae'', order ''Picornavirales'', and realm '' Riboviria''. There are 158 species in this family, assigned to 68 genera. Notable examples are genera ''Enterovirus'' (including ''Rhinovirus'' and ''Poliovirus''), ''Aphthovirus'', ''Cardiovirus'', and ''Hepatovirus''. Etymology The name "picornavirus" has a dual etymology. Firstly, the name derives from ''picorna''- which is an acronym for "''p''oliovirus, ''i''nsensitivity to ether, ''c''oxsackievirus, ''o''rphan virus, ''r''hinovirus, and ribo''n''ucleic ''a''cid". Secondly, the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
