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| The '''World3''' [[model (abstract)|model]] is a [[computer simulation]] of interactions between population, industrial growth, food production and limits in the [[ecosystem]]s of the Earth. It was originally produced and used by a [[Club of Rome]] study that produced the model and the book ''[[The Limits to Growth]]''. The principal creators of the model were [[Donella Meadows]], [[Dennis Meadows]], and [[Jørgen Randers]].
| | It is very common to have a dental emergency -- a fractured tooth, an abscess, or severe pain when chewing. Over-the-counter pain medication is just masking the problem. Seeing an emergency dentist is critical to getting the source of the problem diagnosed and corrected as soon as possible.<br><br>Here are some common dental emergencies:<br>Toothache: The most common dental emergency. This generally means a badly decayed tooth. As the pain affects the tooth's nerve, treatment involves gently removing any debris lodged in the cavity being careful not to poke deep as this will cause severe pain if the nerve is touched. Next rinse vigorously with warm water. Then soak a small piece of cotton in oil of cloves and insert it in the cavity. This will give temporary relief until a dentist can be reached.<br><br>At times the pain may have a more obscure location such as decay under an old filling. As this can be only corrected by a dentist there are two things you can do to help the pain. Administer a pain pill (aspirin or some other analgesic) internally or dissolve a tablet in a half glass (4 oz) of warm water holding it in the mouth for several minutes before spitting it out. DO NOT PLACE A WHOLE TABLET OR ANY PART OF IT IN THE TOOTH OR AGAINST THE SOFT GUM TISSUE AS IT WILL RESULT IN A NASTY BURN.<br><br>Swollen Jaw: This may be caused by several conditions the most probable being an abscessed tooth. In any case the treatment should be to reduce pain and swelling. An ice pack held on the outside of the jaw, (ten minutes on and ten minutes off) will take care of both. If this does not control the pain, an analgesic tablet can be given every four hours.<br><br>Other Oral Injuries: Broken teeth, cut lips, bitten tongue or lips if severe means a trip to a dentist as soon as possible. In the mean time rinse the mouth with warm water and place cold compression the face opposite the injury. If there is a lot of bleeding, apply direct pressure to the bleeding area. If bleeding does not stop get patient to the emergency room of a hospital as stitches may be necessary.<br><br>Prolonged Bleeding Following Extraction: Place a gauze pad or better still a moistened tea bag over the socket and have the patient bite down gently on it for 30 to 45 minutes. The tannic acid in the tea seeps into the tissues and often helps stop the bleeding. If bleeding continues after two hours, call the dentist or take patient to the emergency room of the nearest hospital.<br><br>Broken Jaw: If you suspect the patient's jaw is broken, bring the upper and lower teeth together. Put a necktie, handkerchief or towel under the chin, tying it over the head to immobilize the jaw until you can get the patient to a dentist or the emergency room of a hospital.<br><br>Painful Erupting Tooth: In young children teething pain can come from a loose baby tooth or from an erupting permanent tooth. Some relief can be given by crushing a little ice and wrapping it in gauze or a clean piece of cloth and putting it directly on the tooth or gum tissue where it hurts. The numbing effect of the cold, along with an appropriate dose of aspirin, usually provides temporary relief.<br><br>In young adults, an erupting 3rd molar (Wisdom tooth), especially if it is impacted, can cause the jaw to swell and be quite painful. Often the gum around the tooth will show signs of infection. Temporary relief can be had by giving aspirin or some other painkiller and by dissolving an aspirin in half a glass of warm water and holding this solution in the mouth over the sore gum. AGAIN DO NOT PLACE A TABLET DIRECTLY OVER THE GUM OR CHEEK OR USE THE ASPIRIN SOLUTION ANY STRONGER THAN RECOMMENDED TO PREVENT BURNING THE TISSUE. The swelling of the jaw can be reduced by using an ice pack on the outside of the face at intervals of ten minutes on and ten minutes off.<br><br>If you liked this write-up and you would certainly like to obtain additional information concerning [http://www.youtube.com/watch?v=90z1mmiwNS8 Best Dentists in DC] kindly see the web-page. |
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| The model was documented in the book ''Dynamics of Growth in a Finite World''. It added new features to [[Jay W. Forrester]]'s World2 model. Since World3 was originally created it has had minor tweaks to get to the World3/91 model used in the book ''[[Beyond the Limits]]'', later improved to get the World3/2000 model distributed by the [[Institute for Policy and Social Science Research]] and finally the World3/2004 model used in the book [[Limits to growth: the 30 year update]].
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| World3 is one of several global models that have been generated throughout the world (Mesarovic/Pestel Model, Bariloche Model, MOIRA Model, SARU Model, FUGI Model, UN World Model) and is probably the model that generated the spark for all later models.
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| == Model ==
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| The model consisted of several interacting parts. Each of these dealt with a different system of the model. The main systems were
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| *the food system, dealing with agriculture and food production,
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| *the industrial system,
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| *the population system,
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| *the non-renewable resources system,
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| *the pollution system.
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| === Agricultural system ===
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| The simplest useful view of this system is that land and [[fertilizer]] are used for [[farm]]ing, and more of either will produce more food. In the context of the model, since land is finite, and industrial output required to produce fertilizer and other [[agricultural]] inputs can not keep up with demand, there necessarily will be a food collapse at some point in the future.
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| === Nonrenewable resources system ===
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| {{main|World3 nonrenewable resource sector}}
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| The nonrenewable resource system starts with the assumption that the total amount of resources available is finite (about 110 times the consumption at 1990s rates for the world3/91 model). These resources can be extracted and then used for various purposes in other systems in the model. An important assumption that was made is that as the nonrenewable resources are extracted, the remaining resources are increasingly difficult to extract, thus diverting more and more industrial output to resource extraction.
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| === Reference run predictions ===
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| The Dynamics of Growth in a Finite World book provides multiple different scenarios. The "reference run" is the one that the authors state "represent the most likely behavior mode of the system if the process of industrialization in the future proceeds in a way very similar to its progress in the past, and if technologies and value changes that have already been institutionalized continue to evolve."<ref>Dynamics of Growth in a Finite World, pg 502</ref> In this scenario, in 2000, the world population reaches 6 billion, and then goes on to peak at 7 billion in 2030. After that population declines because of an increased death rate. In 2015, both industrial output per capita and food per capita peak at 375 dollars/person (1970s dollars) and 500 vegetable-equivalent kilograms/person. The persistent pollution peaks in the year 2035 at 11 times 1970s levels.<ref>Dynamics of Growth in a Finite World, pg 500</ref>
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| == Criticism of the model ==
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| There has been quite a bit of criticism of the World3 model. Some has come from the model creators themselves, some has come from economists and some has come from other places.
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| One of the major criticisms of the model is that it simply has not reflected the reality of the world since the 1970s when the model was first published.{{fact|date=January 2011}} At least one study,<ref>{{cite doi|10.1016/j.gloenvcha.2008.05.001}}</ref> however, claims that "30 years of historical data compare favorably with key features of a business-as-usual scenario called the 'standard run' scenario" produced by the World3 model.
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| In the book ''Groping in the Dark: The First Decade of Global Modelling,''<ref>''Groping in the Dark: The First Decade of Global Modelling'' (Page 129)</ref> [[Donella Meadows]] states: | |
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| :We have great confidence in the basic qualitative assumptions and conclusions about the instability of the current global socioeconomic system and the general kinds of changes that will and will not lead to stability. We have relatively great confidence in the feedback-loop structure of the model, with some exceptions which I list below. We have a mixed degree of confidence in the numerical parameters of the model; some are well-known physical or biological constants that are unlikely to change, some are statistically derived social indices quite likely to change, and some are pure guesses that are perhaps only of the right order of magnitude. The structural assumptions in World3 that I consider most dubious and also sensitive enough to be of concern are:
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| *the constant capital-output ratio (which assumes no diminishing returns to capital),
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| *the residual nature of the investment function,
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| *the generally ineffective labour contribution to output.
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| A detailed criticism of the model is in the book ''Models of Doom: A Critique of the Limits to Growth''.<ref>Models of Doom, A Critique of the Limits to Growth, edited by H.S.D. Cole, Christoper Freeman, Marie Jahoda, and K.L.R. Pavitt. 1973 ISBN 0-87663-905-8</ref>
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| Both [[Julian Lincoln Simon]] and [[Bjørn Lomborg]] have discussed the assumptions that the model makes. {{citation needed|date=June 2013}} The first assumption that they criticize is the assumption of finite natural resources. They also state that the limits on agriculture are invalid since they are based on the limit of the amount of land.
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| [[Vaclav Smil]] disagreed with the combination of physically different processes into simplified equations:
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| :But those of us who knew the [[DYNAMO (programming language)|DYNAMO]] language in which the simulation was written and those who took the model apart line-by-line quickly realized that we had to deal with an exercise in misinformation and obfustication rather than with a model delivering valuable insights. I was particularly astonished by the variables labelled ''Nonrenewable Resources'' and ''Pollution''. Lumping together (to cite just a few scores of possible examples) highly substitutable but relatively limited resources of liquid oil with unsubstitutable but immense deposits of sedimentary phosphate rocks, or short-lived atmospheric gases with long-lived radioactive wastes, struck me as extraordinarily meaningless. <ref> ''Energy at the Crossroads'' ISBN 0-262-69324-0 pg 168</ref>
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| He does however consider continuous growth in world GDP a problem:
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| :Only the widespread scientific illiteracy and innumeracy -- all you need to know in this case is how to execute the equation <math>y = x * e^{rt}</math>-- prevents most of the people from dismissing the idea of sustainable growth at healthy rates as an oxymoronic stupidity whose pursuit is, unfortunately, infinitely more tragic than comic. After all, even cancerous cells stop growing once they have destroyed the invaded tissues. <ref>''Energy at the Crossroads'' ISBN 0-262-69324-0 pg 338-339</ref> | |
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| The authors of the book [[Surviving 1,000 Centuries]] consider some of the predictions too pessimistic, but some of the overall message correct.
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| :...[We] come to the well-known study, ''Limits to Growth'', published under the sponsorship of the 'Club de Rome' - an influential body of private individuals. A first attempt was made to make a complete systems analysis of the rapidly growing human-biological-resource-pollution system. In this analysis the manifold interactions between the different parts were explicitly taken into account. The conclusion was that disaster was waiting around the corner in a few decades because of resource exhaustion, pollution and other factors. Now, 35 years later, our world still exists, ... So the 'growth lobby' has laughed and proclaimed that ''Limits to Growth'' and, by extension, the environmental movements may be forgotten. This entirely misses the point. Certainly the timescale of the problems was underestimated in ''Limits to Growth'', giving us a little more time than we thought. Moreover, during the last three decades a variety of national or collaborative international measures have been taken that have forced reductions in pollution, as we shall discuss. A shining example of this is the Montreal Protocol (1987) that limited the industrial production of fluorocarbons that damage the ozone layer and generated the 'ozone hole' over Antarctica. The publication of ''Limits to Growth'' has greatly contributed towards creating the general willingness of governments to consider such issues. Technological developments have also lead to improvements in the efficiency of the use of energy and other resources, but, most importantly, the warnings from Malthus onward have finally had their effect as may be seen from the population-limiting policies followed by China and, more hesitantly, by India. Without such policies all other efforts would be in vain. However, the basic message of ''Limits to Growth'', that exponential growth of our world civilization cannot continue very long and that a very careful management of the planet is needed, remain as valid as ever. <ref>''Surviving 1,000 Centuries'' ISBN 978-0-387-74633-3 pg 4-5 Roger-Maurice Bonnet and Lodewijk Woltjer.</ref>
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| == References ==
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| {{reflist}}
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| == External links and references ==
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| * [http://www.world3simulator.org/ World3-03 Simulator - runs scenarios discussed in Limits to Growth the 30-Year Update]
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| * [http://insightmaker.com/insight/1954 Interactive online World3 simulation]
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| * [http://www.unh.edu/ipssr/ The Institute for Policy and Social Science Research]
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| * [http://www.rpi.edu/~simonk/ESP/BTL4MacDownload.html Macintosh version of the Simulation by Kenneth L. Simons]
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| *[http://majorityrights.com/index.php/weblog/comments/forresters_limits_to_growth_model_for_your_personal_computer/ Running the World3 model on a pc]
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| * [http://www.modelica.org/libraries/SystemDynamics/releases/2.0 Implementation of the World3 model] in the simulation language [[Modelica]]
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| * ''Dynamics of Growth in a Finite World'', by Dennis L. Meadows, William W. Behrens III, Donella H. Meadows, Roger F. Naill, Jorgen Randers, and Erich K.O. Zahn. 1974 ISBN 0-9600294-4-3
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| * ''World Dynamics'', by Jay Wright Forrester. 1973 ISBN 0-262-56018-6
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| * [http://www.clubofrome.org/docs/limits.rtf The Limits to Growth] (Abstract, 8 pages, by [[Eduard Pestel]]. A Report to The Club of Rome (1972), by Donella H. Meadows, Dennis l. Meadows, Jorgen Randers, William W. Behrens III)
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| * [http://www.chelseagreen.com/2005/items/ltgcd Limits to Growth, The 30-Year Update], by Dennis Meadows and Eric Tapley. 2004 CDRom with World3-2004 model. ISBN 1-931498-85-7
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| * [http://bit-player.org/extras/limits/ Javascript world 3 simulator]
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| * [http://www.thwink.org/sustain/articles/021_WorldChangeModel/index.htm WorldChange Model]. This adds a [[sustainability and systemic change resistance|change resistance]] subsystem to World3 in order to more correctly analyze and simulate why [[sustainability science]] has so far been unable to solve the [[sustainability]] problem.
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| {{population}}
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| [[Category:Economics models]]
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| [[Category:Environmental economics]]
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| [[Category:Systems theory]]
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| [[Category:Simulation software]]
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| [[Category:Energy models]]
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It is very common to have a dental emergency -- a fractured tooth, an abscess, or severe pain when chewing. Over-the-counter pain medication is just masking the problem. Seeing an emergency dentist is critical to getting the source of the problem diagnosed and corrected as soon as possible.
Here are some common dental emergencies:
Toothache: The most common dental emergency. This generally means a badly decayed tooth. As the pain affects the tooth's nerve, treatment involves gently removing any debris lodged in the cavity being careful not to poke deep as this will cause severe pain if the nerve is touched. Next rinse vigorously with warm water. Then soak a small piece of cotton in oil of cloves and insert it in the cavity. This will give temporary relief until a dentist can be reached.
At times the pain may have a more obscure location such as decay under an old filling. As this can be only corrected by a dentist there are two things you can do to help the pain. Administer a pain pill (aspirin or some other analgesic) internally or dissolve a tablet in a half glass (4 oz) of warm water holding it in the mouth for several minutes before spitting it out. DO NOT PLACE A WHOLE TABLET OR ANY PART OF IT IN THE TOOTH OR AGAINST THE SOFT GUM TISSUE AS IT WILL RESULT IN A NASTY BURN.
Swollen Jaw: This may be caused by several conditions the most probable being an abscessed tooth. In any case the treatment should be to reduce pain and swelling. An ice pack held on the outside of the jaw, (ten minutes on and ten minutes off) will take care of both. If this does not control the pain, an analgesic tablet can be given every four hours.
Other Oral Injuries: Broken teeth, cut lips, bitten tongue or lips if severe means a trip to a dentist as soon as possible. In the mean time rinse the mouth with warm water and place cold compression the face opposite the injury. If there is a lot of bleeding, apply direct pressure to the bleeding area. If bleeding does not stop get patient to the emergency room of a hospital as stitches may be necessary.
Prolonged Bleeding Following Extraction: Place a gauze pad or better still a moistened tea bag over the socket and have the patient bite down gently on it for 30 to 45 minutes. The tannic acid in the tea seeps into the tissues and often helps stop the bleeding. If bleeding continues after two hours, call the dentist or take patient to the emergency room of the nearest hospital.
Broken Jaw: If you suspect the patient's jaw is broken, bring the upper and lower teeth together. Put a necktie, handkerchief or towel under the chin, tying it over the head to immobilize the jaw until you can get the patient to a dentist or the emergency room of a hospital.
Painful Erupting Tooth: In young children teething pain can come from a loose baby tooth or from an erupting permanent tooth. Some relief can be given by crushing a little ice and wrapping it in gauze or a clean piece of cloth and putting it directly on the tooth or gum tissue where it hurts. The numbing effect of the cold, along with an appropriate dose of aspirin, usually provides temporary relief.
In young adults, an erupting 3rd molar (Wisdom tooth), especially if it is impacted, can cause the jaw to swell and be quite painful. Often the gum around the tooth will show signs of infection. Temporary relief can be had by giving aspirin or some other painkiller and by dissolving an aspirin in half a glass of warm water and holding this solution in the mouth over the sore gum. AGAIN DO NOT PLACE A TABLET DIRECTLY OVER THE GUM OR CHEEK OR USE THE ASPIRIN SOLUTION ANY STRONGER THAN RECOMMENDED TO PREVENT BURNING THE TISSUE. The swelling of the jaw can be reduced by using an ice pack on the outside of the face at intervals of ten minutes on and ten minutes off.
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