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COMPLEX TIME: Adaptation, Aging, & Arrow of Time

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test 123test WikiWorks3Dec 5 at 2:42 pmUser:WikiWorks3
test messagetestWikiWorksOct 15 at 11:58 amComplex Time:Extension tests
One thing we didn't discuss much is the increased epileptic seizure risk from prolonged awakening. This is an aspect of sleep-wake physiology that could be addressed with Alex's or Kim's clinical datasets. But it also is a community health problem, seizures aren't diagnosed as epilepsy if they only follow sleep deprivation because seizure threshold so low in that state. For a basic neuroscience view on this, see 'Human Cortical Excitability Increases with Time Awake' (Kim added to references).Danger of seizure from overloadKimberleyWhiteheadNov 25 at 3:32 pmWhat is Sleep?npar-2151
Therapeutic hypothermia (following brain injury) could be used to further test this. Certainly in human neonates, they still sleep cycle during the hypothermia. Clinical practice slightly varies, so there will be some infants with the same extent of brain damage but some cooled and some not. Kim will try to address this question in her new brain injury grant.Effects of temperature on sleep in humansKimberleyWhiteheadNov 25 at 3:23 pmWhat is Sleep?npar-2151
Both Gina and Bob suggested non-REM sleep first plays a memory function and then REM sleep is either 'creative' with the memories (Bob) or 'cleans up' further (Gina). In neonates the order is reversed - REM sleep occurs at sleep onset, and then non-REM - but babies still have multiple cycles before awakening. So the concept seems to hold that they have multiple cycles in case, if they are wakened early, they'll have had at least one cycle which includes BOTH states, indicating the two have to occur together to be efficacious.Order of non-REM and REM sleepKimberleyWhiteheadNov 25 at 3:11 pmWhat is Sleep?npar-2129
Yes. Similar ideas should be relevant within a tumor, although the adaptive landscape will now mostly be dictated by the tumor microenvironment, not the “tissue microenvironment”.  Bob Gatenby and Bob Gillies (both at Moffitt) have done nice mathematical modeling for how the tumor microenvironment changes, creating new hurdles that must be cleared by adaptation. Regarding whether fitness landscapes are similarly relevant in a full blown cancerJamesDeGregoriApr 22 at 2:21 pmHallmarks of Biological Failurenpar-1677
Regarding the exponential decline in the body late in life, we believe that we know the evolutionary reason based on life history theory, but not really the proximate explanations. Do systems (organs, tissues) have a certain level of resiliency, evolved dependent on life history, that “gives way” late in life? Does somatic maintenance ever really wane, or was regular maintenance only good enough to get an animal’s body so far?Exponential decline late in life (we don't just go downhill. we pick up speed.)JamesDeGregoriApr 22 at 2:19 pmHallmarks of Biological Failurenpar-1677
I think that we are always learning and changing. I have been leaving memory out of my system because the immune memory is so strong in mice with respect to malaria that the parasite fails to grow at all during a second infection. Your return to an origin depends on the axes you decide to use to measure your system. Instead of measuring entropy, maybe scientists could measure grant dollars spent as an arrow of time. Do you return to the same place that you began?DavidSchneiderApr 10 at 7:13 pmHallmarks of Biological Failurenpar-1669
[In case you / others are interested in discussing about this, I would continue the conversation about "generality" in ecology here [[On the role of general theory in ecology]] ] A model / theory is useful for understanding the data, including the ones you have not collected. A general theory/model is just a theory/model that has some extrapolative/predictive power. The non trivial question is how much general is too much general (and how much specific is overfitting)... but I do not understand why we should not care about generality.Response to Samraat from Greg DwyerJacopoGrilliFeb 27 at 11:06 pmIrreversible Processes in Ecological Evolutionnpar-1509
"Ecology has a long and tedious history of theory that has little do with the concerns of empiricists. Part of the problem was that the theory was often untestable, and that has been a huge problem." I *strongly* agree! (I posted the notes & pictures from the final discussion)The meaning of life still doesn't interest me...JacopoGrilliFeb 27 at 11:00 pmIrreversible Processes in Ecological Evolutionnpar-1490
To tell you the truth, Samraat, I don't care about generality at all. Too much of ecology is focused on a fruitless search for generality. To me, the interesting question, is a model or a theory useful for understanding data, or isn't it? Maybe I'm narrow minded, but I have seen so much really boring efforts to achieve generality. Ecology is rife with that stuff.Response to Samraat from Greg DwyerGregDwyerFeb 17 at 11:10 pmIrreversible Processes in Ecological Evolutionnpar-1509
Dervis is of course trying to yank my chain, here, and that's fair enough, but there's also an issue worth discussing. First, I'm going to say a little more about where I was coming from. Ecology has a long and tedious history of theory that has little do with the concerns of empiricists. Part of the problem was that the theory was often untestable, and that has been a huge problem. For theory to be truly useful in applications, however, I think it has to explain the consequences of quantities that can be tested. From that perspective, at the end of the meeting, we finally began to focus on statistics that might act as signatures of irreversibility. That is when I began to be interested. Hopefully @Jacopo will at some point post the notes from the end of that discussion, I can see if I still believe in irreversibility as something that can actually be studied. The meaning of life still doesn't interest me...GregDwyerGregDwyerFeb 17 at 10:43 pmFeb 17 at 11:01 pmIrreversible Processes in Ecological Evolutionnpar-1490
A constraint is not a constrained region in the phenotypic space. It is a high fitness region of the space that cannot be reached because of an impediment that is external to the factor that is exerting selection. Question of selection and constraintsPriyangaAmarasekareJan 31 at 7:21 pmIrreversible Processes in Ecological Evolutionnpar-1490
The idea of "cheaters" came up often during discussion. In the work presented by Otto, the emergence of cheaters could be caused by the loss of a certain gene. Discussion on how cheaters emerge and if adopting a cheating strategy is reversible might be interesting. General ideas: Talks ranged from thinking about time from a long lived forest ecosystem, to microbial, to evolutionary scales. What is the relationship between time, scale, and irreversibly? Do different systems that exist in similar time scales have similar properties of irreversibly? Can we construct general rules about which systems are reversible? Ashley Teufel (SFI)AshleyTeufelJan 31 at 12:07 amIrreversible Processes in Ecological Evolutionnpar-1500
Yes! But you might disagree... let's discuss! [ (IMHO this is a good starting point] )Do we care about general theories?JacopoGrilliJacopoGrilliJan 30 at 11:50 pmJan 30 at 11:50 pmOn the role of general theory in ecology0
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atestWikiworksJan 11 at 2:16 pmDynamic Multi-System Resilience in Human Agingnpar-{{PAGEID:{{{1|}}}}}