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Old November 7, 2009, 10:08 AM   #101
Pasteur
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If all 33 of the cases exhibit these microbleeds, then you have a problem since the likelihood of all those cases just happening to match your 1000psi criterion for handgun BPW effects is really slim. There will definitely be cases in there where the pressures involved are not adequate to match your threshold for BPW requirements.
Credible criticism of a published theory should at least demonstrate a working understanding of the theory. Does the published theory predict that GSWs to the chest below 1000 psi will not exhibit distant wounding effects, or that distant effects above 1000 psi will be more likely and easier to see? Your reasoning is analogous to claiming that a published analysis predicting broken legs are more likely for falls above 5 feet is contradicted by reports of broken legs from lower heights. Your reasoning is analogous to claimimg that a published study predicting lung cancer is more likely for smokers of two packs a day is contradicted by findings of lung cancer in smokers of one pack a day.

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Anyway you have specified that a positive finding on the Military Acute Concussion Evaluation (MACE) in the presence of a GSW to the chest is indicative of mild traumatic brain injury which (in the absence of other factors) has to be from the BPW. That's fine, let's go with that.
MACE can be useful tool for helping to diagnose mTBI, but I don’t think it can provide solid confirmation of remote brain injury due to ballistic pressure waves from well-centered chest hits, because in nearly all cases of center chest hits with large enough BPW to expect mTBI, ischemia/reperfusion will be a confounding factor in surviving patients. The simplest way to eliminate ischemia/reperfusion as a confounding factor is to focus on cases where the GSW caused rapid death as in the human autopsy study and your suggested approach to a deer study. MACE might be useful in telling us whether GSWs to the chest can cause mTBI, how can it distinguish the BPW mechanism from ischemia/reperfusion?
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Old November 7, 2009, 08:04 PM   #102
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Credible criticism of a published theory should at least demonstrate a working understanding of the theory. Does the published theory predict that GSWs to the chest below 1000 psi will not exhibit distant wounding effects, or that distant effects above 1000 psi will be more likely and easier to see? Your reasoning is analogous to claiming that a published analysis predicting broken legs are more likely for falls above 5 feet is contradicted by reports of broken legs from lower heights. Your reasoning is analogous to claimimg that a published study predicting lung cancer is more likely for smokers of two packs a day is contradicted by findings of lung cancer in smokers of one pack a day.
Reading comprehension is key here.
As you can see from the paragraph immediately after the one you have selectively quoted, the issue is about BPW as a means of incapacitating humans within 5 seconds. That's what your main selling point has been all along. The summary is that microscopic effects without clinical symptoms AND without the ability to incapacitate within 5 seconds puts this Czech research in the 'not relevant' category as far as your claims are concerned. Unless of course, you are changing your claims...

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but I don’t think it can provide solid confirmation of remote brain injury due to ballistic pressure waves from well-centered chest hits, because in nearly all cases of center chest hits with large enough BPW to expect mTBI, ischemia/reperfusion will be a confounding factor in surviving patients.
How do you know that?
Care to specify what sort of ischaemic event you are talking about?
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Old November 8, 2009, 10:18 AM   #103
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the issue is about BPW as a means of incapacitating humans within 5 seconds. That's what your main selling point has been all along.
Neither this thread, nor the Brain Injury paper predicting remote brain injury in humans shot in the chest has talked much about “incapacitating humans within 5 seconds.” This thread is about the confirmation of this prediction (first published in 2007) of remote brain injury for humans shot in the chest in an autopsy study that documented the predicted distant brain injury. There are a number of published papers related to BPW. Some papers concentrate on documentation of remote injury mechanisms as a medical issue. Others concentrate on rapid incapacitation, which is more directly related to ammunition selection. The issues are related, but not exactly the same. Some have claimed that since remote wounding mechanisms do not exist, that BPW cannot possibly contribute to rapid incapacitation. Therefore, studies documenting remote injuries are an important refutation of the errant viewpoint of "sole wounding mechanisms."

You are right that the human autopsy study does not directly address the issue of rapid incapacitation; it addresses the issue of remote injury without suggesting whether the observed level of remote injury is sufficient to contribute to rapid incapacitation. Other studies address what BPW levels are necessary to contribute to rapid incapacitation. A published deer study shows that a high BPW handgun bullet incapacitated deer much more rapidly than a low BPW handgun bullet. Other papers have shown EEG suppression and correlation between BPW magnitude and rapid incapacitation. One might criticize these papers for not including brain histology, but these papers focused on rapid incapacitation rather than distant injury.

Previously published studies suggested that distant brain damage is possible at levels that might not contribute to rapid incapacitation. The 2008 paper, “Scientific Evidence for Hydrostatic Shock” explains:

Energy Transfer Required for Remote Neural Effects
… handgun levels of energy transfer can produce pressure waves leading to incapacitation and injury.[29][30][26][31][32] The work of Suneson et al. also suggests that remote neural effects can occur with levels of energy transfer possible with handguns (roughly 500 ft lbs/700 joules).

Using sensitive biochemical techniques, the work of Wang et al. suggests even lower impact energy thresholds for remote neural injury to the brain. In analysis of experiments of dogs shot in the thigh they report highly significant neural effects in the hypothalamus and hippocampus (regions of the brain) with energy transfer levels close to 150 ft-lbs. They also report less significant remote neural effects in the hypothalamus with energy transfer just under 100 ft-lbs.[19]

Even though Wang et al. document remote neural damage for low levels of energy transfer, these levels of neural damage are probably too small to contribute to rapid incapacitation. Courtney and Courtney suggest that remote neural effects only begin to make significant contributions to rapid incapacitation for ballistic pressure wave levels above 500 PSI (corresponds to transferring roughly 300 ft-lbs in 12 inches of penetration) and become easily observable above 1000 PSI (corresponds to transferring roughly 600 ft-lbs in 1 foot of penetration).[29] Incapacitating effects in this range of energy transfer are consistent with observations of remote spinal injuries,[15] observations of suppressed EEGs and breathing interruptions in pigs,[27][33] and with observations of incapacitating effects of ballistic pressure waves without a wound channel.[34]


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Unless of course, you are changing your claims...
This thread began discussing the prediction of remote brain injury in humans shot in the chest, first published in 2007, and its confirmation in a human autopsy study, published in 2009. How can you suggest that this is a new claim?
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