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Evolutionary Therapy
Evolutionary therapy is a subfield of evolutionary medicine that utilizes concepts from evolutionary biology in management of diseases caused by evolving entities such as cancer and microbial infections. These evolving disease agents adapt to selective pressure introduced by treatment, allowing them to develop resistance to therapy, making it ineffective. Evolutionary therapy relies on the notion that Darwinian evolution is the main reason behind lethality of late stage cancer and multi-drug resistant bacterial infections such as methicillin-resistant ''Staphylococcus aureus''. Thus, evolutionary therapy suggests that treatment of such highly dynamic evolving diseases should be changing over time to account for changes in disease populations. Adaptive treatment strategies typically cycle between different drugs or drug doses to take advantage of predictable patterns of disease evolution. This is in contrast to standardized treatment approach which is applied to all patients and eq ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Evolutionary Medicine
Evolutionary medicine or Darwinian medicine is the application of modern evolutionary theory to understanding health and disease. Modern biomedical research and practice have focused on the molecular and physiological mechanisms underlying health and disease, while evolutionary medicine focuses on the question of why evolution has shaped these mechanisms in ways that may leave us susceptible to disease. The evolutionary approach has driven important advances in the understanding of cancer, autoimmune disease, and anatomy. Medical schools have been slower to integrate evolutionary approaches because of limitations on what can be added to existing medical curricula. ThInternational Society for Evolution, Medicine and Public Healthcoordinates efforts to develop the field. It owns the Oxford University Press journaEvolution, Medicine and Public HealthanThe Evolution and Medicine Review Core principles Utilizing the Delphi method, 56 experts from a variety of disciplines, includin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Optimal Control
Optimal control theory is a branch of mathematical optimization that deals with finding a control for a dynamical system over a period of time such that an objective function is optimized. It has numerous applications in science, engineering and operations research. For example, the dynamical system might be a spacecraft with controls corresponding to rocket thrusters, and the objective might be to reach the moon with minimum fuel expenditure. Or the dynamical system could be a nation's economy, with the objective to minimize unemployment; the controls in this case could be fiscal and monetary policy. A dynamical system may also be introduced to embed operations research problems within the framework of optimal control theory. Optimal control is an extension of the calculus of variations, and is a mathematical optimization method for deriving control policies. The method is largely due to the work of Lev Pontryagin and Richard Bellman in the 1950s, after contributions to calc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Prostate Cancer
Prostate cancer is cancer of the prostate. Prostate cancer is the second most common cancerous tumor worldwide and is the fifth leading cause of cancer-related mortality among men. The prostate is a gland in the male reproductive system that surrounds the urethra just below the bladder. It is located in the hypogastric region of the abdomen. To give an idea of where it is located, the bladder is superior to the prostate gland as shown in the image The rectum is posterior in perspective to the prostate gland and the ischial tuberosity of the pelvic bone is inferior. Only those who have male reproductive organs are able to get prostate cancer. Most prostate cancers are slow growing. Cancerous cells may spread to other areas of the body, particularly the bones and lymph nodes. It may initially cause no symptoms. In later stages, symptoms include pain or difficulty urinating, blood in the urine, or pain in the pelvis or back. Benign prostatic hyperplasia may produce similar symptoms ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stochastic
Stochastic (, ) refers to the property of being well described by a random probability distribution. Although stochasticity and randomness are distinct in that the former refers to a modeling approach and the latter refers to phenomena themselves, these two terms are often used synonymously. Furthermore, in probability theory, the formal concept of a ''stochastic process'' is also referred to as a ''random process''. Stochasticity is used in many different fields, including the natural sciences such as biology, chemistry, ecology, neuroscience, and physics, as well as technology and engineering fields such as image processing, signal processing, information theory, computer science, cryptography, and telecommunications. It is also used in finance, due to seemingly random changes in financial markets as well as in medicine, linguistics, music, media, colour theory, botany, manufacturing, and geomorphology. Etymology The word ''stochastic'' in English was originally used as a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heterogeneity
Homogeneity and heterogeneity are concepts often used in the sciences and statistics relating to the uniformity of a substance or organism. A material or image that is homogeneous is uniform in composition or character (i.e. color, shape, size, weight, height, distribution, texture, language, income, disease, temperature, radioactivity, architectural design, etc.); one that is heterogeneous is distinctly nonuniform in at least one of these qualities. Heterogeneous Mixtures, in chemistry, is where certain elements are unwillingly combined and, when given the option, will separate. Etymology and spelling The words ''homogeneous'' and ''heterogeneous'' come from Medieval Latin ''homogeneus'' and ''heterogeneus'', from Ancient Greek ὁμογενής (''homogenēs'') and ἑτερογενής (''heterogenēs''), from ὁμός (''homos'', “same”) and ἕτερος (''heteros'', “other, another, different”) respectively, followed by γένος (''genos'', “kind”); - ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anthropocene
The Anthropocene ( ) is a proposed geological epoch dating from the commencement of significant human impact on Earth's geology and ecosystems, including, but not limited to, anthropogenic climate change. , neither the International Commission on Stratigraphy (ICS) nor the International Union of Geological Sciences (IUGS) has officially approved the term as a recognised subdivision of geologic time, although the Anthropocene Working Group (AWG) of the Subcommission on Quaternary Stratigraphy (SQS) of the ICS voted in April 2016 to proceed towards a formal golden spike (GSSP) proposal to define the Anthropocene epoch in the geologic time scale (GTS) and presented the recommendation to the International Geological Congress in August 2016. In May 2019, the AWG voted in favour of submitting a formal proposal to the ICS by 2021, locating potential stratigraphic markers to the mid-twentieth century of the common era. This time period coincides with the start of the Great Acce ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Commensalism
Commensalism is a long-term biological interaction (symbiosis) in which members of one species gain benefits while those of the other species neither benefit nor are harmed. This is in contrast with mutualism, in which both organisms benefit from each other; amensalism, where one is harmed while the other is unaffected; parasitism, where one is harmed and the other benefits, and parasitoidism, which is similar to parasitism but the parasitoid has a free-living state and instead of just harming its host, it eventually ends up killing it. The commensal (the species that benefits from the association) may obtain nutrients, shelter, support, or locomotion from the host species, which is substantially unaffected. The commensal relation is often between a larger host and a smaller commensal; the host organism is unmodified, whereas the commensal species may show great structural adaptation consistent with its habits, as in the remoras that ride attached to sharks and other fishes. Remo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Competitive Exclusion Principle
In ecology, the competitive exclusion principle, sometimes referred to as Gause's law, is a proposition that two species which compete for the same limited resource cannot coexist at constant population values. When one species has even the slightest advantage over another, the one with the advantage will dominate in the long term. This leads either to the extinction of the weaker competitor or to an evolutionary or behavioral shift toward a different ecological niche. The principle has been paraphrased in the maxim "complete competitors can not coexist". History The competitive exclusion principle is classically attributed to Georgy Gause, although he actually never formulated it. The principle is already present in Darwin's theory of natural selection. Throughout its history, the status of the principle has oscillated between ''a priori'' ('two species coexisting ''must'' have different niches') and experimental truth ('we find that species coexisting do have different niches' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Frequency-dependent Selection
Frequency-dependent selection is an evolutionary process by which the fitness (biology), fitness of a phenotype or genotype depends on the phenotype or genotype composition of a given population. * In positive frequency-dependent selection, the fitness of a phenotype or genotype increases as it becomes more common. * In negative frequency-dependent selection, the fitness of a phenotype or genotype decreases as it becomes more common. This is an example of balancing selection. * More generally, frequency-dependent selection includes when biological interactions make an individual's fitness depend on the frequencies of other phenotypes or genotypes in the population. Frequency-dependent selection is usually the result of interactions between species (predation, parasitism, or competition), or between genotypes within species (usually competitive or symbiotic), and has been especially frequently discussed with relation to anti-predator adaptations. Frequency-dependent selection can lea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Evolutionary Game Theory
Evolutionary game theory (EGT) is the application of game theory to evolving populations in biology. It defines a framework of contests, strategies, and analytics into which Darwinian competition can be modelled. It originated in 1973 with John Maynard Smith and George R. Price's formalisation of contests, analysed as strategies, and the mathematical criteria that can be used to predict the results of competing strategies. Evolutionary game theory differs from classical game theory in focusing more on the dynamics of strategy change. This is influenced by the frequency of the competing strategies in the population. Evolutionary game theory has helped to explain the basis of altruistic behaviours in Darwinian evolution. It has in turn become of interest to economists, sociologists, anthropologists, and philosophers. History Classical game theory Classical non-cooperative game theory was conceived by John von Neumann to determine optimal strategies in competitions between adversa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dynamic Programming
Dynamic programming is both a mathematical optimization method and a computer programming method. The method was developed by Richard Bellman in the 1950s and has found applications in numerous fields, from aerospace engineering to economics. In both contexts it refers to simplifying a complicated problem by breaking it down into simpler sub-problems in a recursive manner. While some decision problems cannot be taken apart this way, decisions that span several points in time do often break apart recursively. Likewise, in computer science, if a problem can be solved optimally by breaking it into sub-problems and then recursively finding the optimal solutions to the sub-problems, then it is said to have ''optimal substructure''. If sub-problems can be nested recursively inside larger problems, so that dynamic programming methods are applicable, then there is a relation between the value of the larger problem and the values of the sub-problems.Cormen, T. H.; Leiserson, C. E.; Rives ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Evolutionary Biology
Evolutionary biology is the subfield of biology that studies the evolutionary processes (natural selection, common descent, speciation) that produced the diversity of life on Earth. It is also defined as the study of the history of life forms on Earth. Evolution is based on the theory that all species are related and they gradually change over time. In a population, the genetic variations affect the physical characteristics i.e. phenotypes of an organism. These changes in the phenotypes will be an advantage to some organisms, which will then be passed onto their offspring. Some examples of evolution in species over many generations are the Peppered Moth and Flightless birds. In the 1930s, the discipline of evolutionary biology emerged through what Julian Huxley called the modern synthesis of understanding, from previously unrelated fields of biological research, such as genetics and ecology, systematics, and paleontology. The importance of studying Evolutionary biology is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
