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Comments

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Firing a Laser Into Your Brain Could Help Beat a Drug Addiction

repapetilto Re:A laser to the brain (156 comments)

Why is this modded down?

about a year ago
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Is "Left" Vs. "Right" Hard-coded Into Your Brain?

repapetilto Re:Cough -- (758 comments)

I don't even think the actual research is a problem. It is more just awful reporting of the results in a completely unscientific fashion that makes it useless while conveying a false sense of certainty. Its so dumb because that ruins the whole point of the exercise and its the cheapest part.

about a year and a half ago
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Is "Left" Vs. "Right" Hard-coded Into Your Brain?

repapetilto Re:Cough -- (758 comments)

True. I will try to make more positive contributions.

about a year and a half ago
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Is "Left" Vs. "Right" Hard-coded Into Your Brain?

repapetilto Re:Cough -- (758 comments)

Thanks for the compliment, although by skeptic I think you really mean "scientist". If you look closely you will find that variations on the above criticisms will apply to almost everything published these days in a large number of fields. It is one thing when people make a new mistake and it gets past reviewers (everyone learns from this process), it is another when the exact same mistakes are made over and over again with no one correcting them, or even encouraging/demanding they be made. Sadly this is the status quo, the same mistakes in logic and presentation of results have persisted for decades now, this is why I mentioned cargo cult science. I think it is an apt description of this type of behaviour.

http://www.lhup.edu/~DSIMANEK/cargocul.htm

about a year and a half ago
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Is "Left" Vs. "Right" Hard-coded Into Your Brain?

repapetilto Re:Cough -- (758 comments)

Here is the main claim made, stated quite confidently:

Figure 1. Republicans and Democrats differ in the neural mechanisms activated while performing a risk-taking task.Republicans more strongly activate their right amygdala, associated with orienting attention to external cues. Democrats have higher activity in their left posterior insula, associated with perceptions of internal physiological states.

-This is an misinterpretation of the result of their analysis. All they can say is that it would be unlikely that the difference between Rep and Dems in measured activation levels would occur by chance if their null model was true (ie no difference + all assumptions are true + they corrected for multiple testing, etc).

Strange sample sizes:

Participant groups were composed of 60 Democrats and 22 Republicans

-There should be some explanation for this. I don't see it. They also used two different scanners, why did this occur? Did they extend the study after initial analysis didn't give a significant result?

Vague description of the analysis:

...for each ROI these individual extracted values were subjected to a "robust" regression implemented within the statistical package R

-What "robost" regression function was used in R? What exactly was done here? Why not provide us with the code and data?
--What assumptions are made when using this method of analysis?
--This term appears to refer to a family of approaches at regression and not a single approach: https://en.wikipedia.org/wiki/Robust_regression

Use of dynamite plots
-Where is all the data?
--Where are the scatter plots showing us the relationship?
--Where is the distributional information about each covariate?

Multiple testing:

As an initial test of our conjecture, we examined 5 mm spheres centered on regions in the amygdala, insula, anterior cingulate cortex, and entorhinal cortex that had been previously identified by Kanai et al. [15]. When these specific portions of the regions failed to demonstrate functional differences, we generated larger, anatomically defined masks of the four areas.

-Fair enough, but they have deviated from their original model and this has now become an exploratory study. All the more reason they should have presented all the data.

Discussion of alternative explanation for results and possible sources of error:
-Where is this? They are the ones that ran the study and have the most information about the experimental situation. It is much more difficult for me to do so based on the summary in this report, this should not be my job.

about a year and a half ago
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Is "Left" Vs. "Right" Hard-coded Into Your Brain?

repapetilto Re:Cough -- (758 comments)

So true. Science is about collecting data, recognizing sources of uncertainty, and accounting for why your model does not fit perfectly over time. What we have now is largely cargo cult science.

about a year and a half ago
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Nature Vs. Nurture: Waging War Over the Soul of Science

repapetilto Re:This is one of the reasons... (235 comments)

What have I said that makes you think that I don't understand the difference between correlation and causation?

about a year and a half ago
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President Obama Calls For New 'Space Race' Funding

repapetilto Re:You have been propagandized (291 comments)

Look at who is spending that money on healthcare. Almost all of it is the elderly and people with chronic conditions receiving treatments aimed at preservation (even the words we use: "cure" rather than "heal" reflect this) that may or may not even be effective at achieving this lesser goal. The emergency room scenario is less than a drop in the bucket and really has no place in discussions about the cost of healthcare.

It certainly appears that "they" have inflated the currency to save the banking system thus wiping out large chunks of the older generations savings. To prevent outrage about this, they are now forcing young people to purchase health insurance they don't need to subsidize the healthcare of their parents/grandparents who would no longer be able to afford it otherwise. It has been sold all the way as a "human right" by conflating health insurance with health care and health care with health.

Buying health insurance was always a scam for young people (under 45), they would be much better off having that money put in a savings account each month rather than gambling against themselves with the insurance companies where the money is gone from the people who will need it later (but goes towards "stimulating the economy" and tax revenues). Now it is just that the system is too big to fail so everyone needs to be forced to participate.

about a year and a half ago
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Asteroid 2012 DA14 Approaches

repapetilto Re:Just your friendly neighborhood physicist (94 comments)

I'd be interested to know if anyone can spot something that would make this simulation invalid in the case of 2012 DA14. I just searched through and copy-pasted excerpts containing the word assumption for effect, but have no idea how important any of these are:

"To implement such a program, it is necessary to make some simplifying assumptions that limit the accuracy of any predictions."
https://www.purdue.edu/impactearth/Content/pdf/Documentation.pdf

assuming that the meteoroid is approximately spherical

For the purposes of the Earth Impact Effects Program, we
assume that the trajectory of the impactor is a straight line
from the top of the atmosphere to the surface, sloping at a
constant angle to the horizon given by the user. Acceleration
of the impactor by the Earthâ(TM)s gravity is ignored, as is
deviation of the trajectory toward the vertical in the case that
terminal velocity is reached, as it may be for small impactors.
The curvature of the Earth is also ignored. The atmosphere is
assumed to be purely exponential:

We define the airburst altitude zb to be the height above the surface at which the impactor diameter L(z)
= 7L0. All the impact energy is assumed to be deposited at this altitude;

if the unbulked breccia lens volume Vbr (i.e., the observed
volume of the breccia lens multiplied by a 90â"95% bulking
correction factor; Grieve and Garvin 1984) is assumed to be
related to the final crater diameter by: Vbr â 0.032Dfr^3

Assuming that the top
surface of the breccia lens is parabolic and that the
brecciation process increases the bulk volume of this
material by 10%

we assume, based on numerical modeling work
(Pierazzo and Melosh 2000; Ivanov and Artemieva 2002), that
the volume of impact melt is roughly proportional to the
volume of the transient crater

Here we assume that the
crater floor diameter is similar to the transient crater diameter

Numerical simulations of vapor
plume expansion (Melosh et al. 1993; Nemtchinov et al. 1998)
predict that the fireball radius at the time of maximum radiation
is 10â"15 times the impactor diameter. We use a value of 13 and
assume âoeyield scalingâ applies to derive a relationship between
impact energy E in joules and the fireball radius in meters

The time at which thermal radiation is at a maximum Tt is
estimated by assuming that the initial expansion of the fireball
occurs at approximately the same velocity as the impact:

for a first-order estimate we
assume Î = 3 Ã-- 10â'3 and ignore the poorly-constrained
velocity dependence.

âoeas a rough approximation, the amount of thermal energy
received at a given distance from a nuclear explosion may be
assumed to be independent of the visibility.â

To calculate the seismic magnitude of an impact event,
we assume that the âoeseismic efficiencyâ (the fraction of the
kinetic energy of the impact that ends up as seismic wave
energy) is one part in ten thousand

we assume that the main seismic wave energy is that
associated with the surface waves.

For simplicity, we ignore the uplifted fraction of the
crater rim material. We estimate the thickness of ejecta at a
given distance from an impact by assuming that the material
lying above the pre-impact ground surface is entirely ejecta,
that it has a maximum thickness te = htr at the transient crater
rim, and that it falls off as one over the distance from the
crater rim cubed

we
assume that the transient crater is a paraboloid with a depth to
diameter ratio of 1:2

assumes that all ejecta is thrown out of the crater from
the same point and at the same angle (45Â) to the horizontal.

we assume that the impact-generated shock wave in
the air is directly analogous to that generated by an explosive
charge detonated at the ground surface

the Mach region is
assumed to begin at the impact point

For convenience, however, we assume that the shock
wave travels at the ambient sound speed in air

The air blast model we use extrapolates from data
recorded after a very small explosion (in impact cratering
terms) in which the atmosphere may be treated as being of
uniform density. Furthermore, at this scale of explosion, the
peak overpressure decays to zero at distances so small (

about a year and a half ago
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Missouri Legislation Redefines Science, Pushes Intelligent Design

repapetilto Re:It's a race... (813 comments)

Ah, thanks for the clarification.

about a year and a half ago
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Missouri Legislation Redefines Science, Pushes Intelligent Design

repapetilto Re:It's a race... (813 comments)

I wouldn't say know. I have observed some instances myself which are consistent with theories I've read in books written by people who have experimented with it more. Thats not to say any of that will be true under every circumstance or there may not be further forces that can come into play.

about a year and a half ago
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Missouri Legislation Redefines Science, Pushes Intelligent Design

repapetilto Re:It's a race... (813 comments)

I have another one. The surface of the ball is already resting on a table and the strong nuclear force prevents any "falling".

about a year and a half ago
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Missouri Legislation Redefines Science, Pushes Intelligent Design

repapetilto Re:It's a race... (813 comments)

The density of the medium relative to that of the falling objects matters as well. You can also do tricks with magnets, or come up with some other situation where forces cancel each other out or lead to the ball moving opposite the direction you would expect from the word "fall".

about a year and a half ago
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Missouri Legislation Redefines Science, Pushes Intelligent Design

repapetilto Re:It's a race... (813 comments)

Yea i was underwater and it was lighter than water. That is just one example. Seriously this stuff shouldn't be riddles to you guys.

about a year and a half ago
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Missouri Legislation Redefines Science, Pushes Intelligent Design

repapetilto Re:It's a race... (813 comments)

I'm sure you can think of circumstances under which that doesn't occur.

about a year and a half ago
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Missouri Legislation Redefines Science, Pushes Intelligent Design

repapetilto Re:It's a race... (813 comments)

I expected this response because you are too uneducated to predict that I knew you would qualify your statement and fail to interpret my purpose in saying that. Now go look up who has ever said that the process of science has proved something. If you come back with more nonsense thats the end of my attempt to help you understand science, but hopefully the seed has been planted.

about a year and a half ago
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Missouri Legislation Redefines Science, Pushes Intelligent Design

repapetilto Re:It's a race... (813 comments)

And why isn't that already normally part of a science curriculum. The discrepancies and unexplained are the most interesting and important part if you want to train a new generation of scientists. Its sad that such a movement is coming from the most superstitious of society.

about a year and a half ago
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Missouri Legislation Redefines Science, Pushes Intelligent Design

repapetilto Re:Teaching different religions' theories (813 comments)

If you think our current theories of the origin of life are factual you are misled. How the hell should people know for sure what happened billions of years ago or even that it was billions of years ago? There are just more and less plausible theories that get selected from based on when a few compete and one turns out to be more useful than the other. The people advocating science really need to learn what it is. I don't believe in god btw (thats not to say something like that can't exist).

about a year and a half ago

Submissions

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Those Cartoons are Back

repapetilto repapetilto writes  |  more than 6 years ago

repapetilto (1219852) writes "CNN reports that newspapers across Europe Wednesday reprinted the controversial cartoon of the Prophet Mohammed that sparked worldwide protests two years ago.

The move came one day after Danish authorities arrested three people allegedly plotting a "terror-related assassination" of Kurt Westergaard, the cartoonist behind the drawing.

Berlingske Tidende, was one of the newspapers involved in the republication by newspapers in Denmark. It said: "We are doing this to document what is at stake in this case, and to unambiguously back and support the freedom of speech that we as a newspaper always will defend," in comments reported by The Associated Press."
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Could Neurons be Signaling Each Other Via Sound?

repapetilto repapetilto writes  |  more than 6 years ago

repapetilto (1219852) writes "Danish Biophysicists challenge the accepted scientific views of how nerves function and of how anesthetics work. Their research suggests that action of nerves is based on sound pulses (propagating pressure waves) and that this explains the phenomenon of anesthesia.

For the more curious of you can find the original papers here"

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