10 MAR 2017 by ideonexus

 1937 Description of Lightspeed Travel

After a while I noticed that the sun and all the stars in his neighborhood were ruddy. Those at the opposite pole of the heaven were of an icy blue. The explanation of this strange phenomenon flashed upon me. I was still traveling, and traveling so fast that light itself was not wholly indifferent to my passage. The overtaking undulations took long to catch me. They therefore affected me as slower pulsations than they normally were, and I saw them therefore as red. Those that met me on my hea...
  1  notes
02 SEP 2016 by ideonexus

 Effects of Good Teachers on Student Outcomes

These findings would suggest that the difference in achievement gains between having a 25th percentile teacher (a not so effective teacher) and a 75th percentile teacher (an effective teacher) is over one-third of a standard deviation (0.35) in reading and almost half a standard deviation (0.48) in mathematics. Similarly, the difference in achievement gains between having a 50th percentile teacher (an average teacher) and a 90th percentile teacher (a very effective teacher) is about one-third...
  1  notes
07 APR 2015 by ideonexus

 Dementia Linked to Carbohydrates

High caloric intake has been associated with an increased risk of cognitive impairment. Total caloric intake is determined by the calories derived from macronutrients. The objective of the study was to investigate the association between percent of daily energy (calories) from macronutrients and incident mild cognitive impairment (MCI) or dementia. Participants were a population-based prospective cohort of elderly persons who were followed over a median 3.7 years (interquartile range, 2.5-3.9...
  1  notes
19 JAN 2012 by ideonexus

 Uniformity, Non-Uniformity, and Irreversibility

We must make the following remark: a proof, that after a certain time t1, the spheres must necessarily be mixed uniformly, whatever may be the initial distribution of states, cannot be given. This is in fact a consequence of probability theory, for any non-uniform distribution of states, no matter how improbable it may be, is still not absolutely impossible. Indeed it is clear that any individual uniform distribution, which might arise after a certain time from some particular initial state, ...
Folksonomies: thermodynamics
Folksonomies: thermodynamics
  1  notes

A heavy passage from Ludwig Eduard Boltzmann on the probability of non-uniform states.

29 JUN 2011 by ideonexus

 The Cultural Bias of the "Growth Curve"

A more flexible construct of normality also has practical applications. As all parents in Western culture know, there is a "normal growth curve" against which all infants are compared when they are brought in for visits to the pediatrician. This standard is used to evaluate babies' growth, and if die baby falls drastically below die curve, pediatricians recommend intervention. But pediatrician Glen Flores, who codirects the Pediatric Latino Clinic at the Boston University School of Medicine, ...
  1  notes

Infants are compared to a growth average, but this average is based on on white, Western infants, other breeds of humans fall beneath or above the curve, resulting in their being considered "abnormal" when they are not.