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== '''[[Oxytocin]]''' ==
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'''Oxytocin''' (Greek: "quick birth") is a [[mammal]]ian [[hormone]] that is secreted into the bloodstream from the [[posterior pituitary]] gland, and that is also released into the [[brain]], where it has effects on social behaviors. In pregnant women, it is secreted into the blood during labor in response to distention of the [[cervix]] and it stimulates contractions of the [[uterus]] to facilitate [[childbirth|birth]]. During [[lactation]], oxytocin is secreted in response to stimulation of the [[nipple]]s by the sucking of the infant, and it stimulates milk let-down in the [[mammary gland]]. Oxytocin is also secreted during [[orgasm]] in both sexes; in men it facilitates movement of [[sperm]]. In the brain, it is involved in social recognition, bonding, sexual arousal, reproductive behaviors and appetite regulation, and might be involved in the formation of trust between people. In some species, including rats, oxytocin also promotes sodium excretion ([[natriuresis]]) and inhibits [[sodium appetite]].<ref>Lee HJ ''et al.'' (2009) Oxytocin: the great facilitator of life.
==Footnotes==
''Prog Neurobiol'' 88:127-51. Review. PMID 19482229</ref><ref>Neumann ID (2008) Brain oxytocin: a key regulator of emotional and social behaviours in both females and males ''J Neuroendocrinol'' 20:858-65. Review.
PMID 18601710</ref><ref>Arthur P ''et al.'' (2007) Oxytocin and parturition: a role for increased myometrial calcium and calcium sensitization? ''Front Biosci''  12:619-33. Review. PMID 17127323</ref>
<ref>Caldwell HK, Young WS III (2006) Oxytocin and vasopressin: genetics and behavioral implications. In Lim R. (ed.) ''Handbook of Neurochemistry and Molecular Neurobiology'' 3rd edition, Springer, New York, pp. 573-607. [http://refworks.springer.com/mrw/fileadmin/pdf/Neurochemistry/0387303480C25.PDF 320kb PDF]</ref>
 
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Latest revision as of 10:19, 11 September 2020

After decades of failure to slow the rising global consumption of coal, oil and gas,[1] many countries have proceeded as of 2024 to reconsider nuclear power in order to lower the demand for fossil fuels.[2] Wind and solar power alone, without large-scale storage for these intermittent sources, are unlikely to meet the world's needs for reliable energy.[3][4][5] See Figures 1 and 2 on the magnitude of the world energy challenge.

Nuclear power plants that use nuclear reactors to create electricity could provide the abundant, zero-carbon, dispatchable[6] energy needed for a low-carbon future, but not by simply building more of what we already have. New innovative designs for nuclear reactors are needed to avoid the problems of the past.

(CC) Image: Geoff Russell
Fig.1 Electricity consumption may soon double, mostly from coal-fired power plants in the developing world.[7]

Issues Confronting the Nuclear Industry

New reactor designers have sought to address issues that have prevented the acceptance of nuclear power, including safety, waste management, weapons proliferation, and cost. This article will summarize the questions that have been raised and the criteria that have been established for evaluating these designs. Answers to these questions will be provided by the designers of these reactors in the articles on their designs. Further debate will be provided in the Discussion and the Debate Guide pages of those articles.

Footnotes

  1. Global Energy Growth by Our World In Data
  2. Public figures who have reconsidered their stance on nuclear power are listed on the External Links tab of this article.
  3. Pumped storage is currently the most economical way to store electricity, but it requires a large reservoir on a nearby hill or in an abandoned mine. Li-ion battery systems at $500 per KWh are not practical for utility-scale storage. See Energy Storage for a summary of other alternatives.
  4. Utilities that include wind and solar power in their grid must have non-intermittent generating capacity (typically fossil fuels) to handle maximum demand for several days. They can save on fuel, but the cost of the plant is the same with or without intermittent sources.
  5. Mark Jacobson believes that long-distance transmission lines can provide an alternative to costly storage. See the bibliography for more on this proposal and the critique by Christopher Clack.
  6. "Load following" is the term used by utilities, and is important when there is a lot of wind and solar on the grid. Some reactors are not able to do this.
  7. Fig.1.3 in Devanney "Why Nuclear Power has been a Flop"