E2science

wolf note (thing) by Calast Fri Sep 03 2004 at 7:48:06

linked by Oolong

A wolf note is a note on a musical instrument, or really anything, that makes the object resonate more than usual. Of course the instrument resonates some all the time, to create sound, but we're talking about unusually large resonance.

Resonance is powerful, it's why protesters can topple over a truck; by pushing and pulling when that action will add to the already occurring motion.

So the wolf note is a given note on an instrument that makes the whole instrument vibrate at that frequency, much louder than the other notes.

Or rather, that's how it works for instruments that aren't meant to work that way. Compare. for example, a pipe organ, a flute, and guitar. A pipe organ has cylinders of specific diameter and length related in such a way (it has to do with wavelengths and the speed of sound) to make the air in the pipes resonate at the note desired. Essentially, a pipe organ plays nothing but wolf notes. Except when the room it's in has resonances in the organ's range, that can get exciting.

The flute is of average diameter with relation to its notes, but the air column is of variable length. When the player blows over the hole, it's exciting the air column, forcing it to resonate at the frequency dictated by the length of the air column.

Then it's useful to look at the example of a guitar. The note a plucked string makes when it's plucked is dictated by string tension, string mass per unit length, and string length. When you use the tuning pegs on a guitar, you're varying the tension. When you switch strings to heavier strings, the mass per unit length rises, and the resonant pitch lowers. When you finger a fret, you're reducing the effective length of the string, raising its resonant frequency.

A wolf note comes along when a string's resonance and the resonance of the guitar as a whole are the same, or even-integer multiples of each other. One vibrating thing moves another. This creates uneven volume levels, and generally, the wolf note's character is different (the proportions of the overtones are different), and is generally undesirable. Although, with new music, who's to say?

The concept can extend to anything that makes variable-pitched sound, a car could conceivably have a wolf note at a given engine RPM. iDan's computer speaker has a wolf note around 2125 Hertz (aka Hz), due to resonances in his computer case. An ideal speaker would not have a wolf note, but in practice, many do. You may notice that the air cavity in your car has a certain wolf note in some music that you listen to, which disappears when you open a window, because the air is no longer captive, instead of the vibrations being contained, they're leaked to the outside. (Incidentally, a closed car is an awesome space for bass, the air cavity's just about the right size for it to be positively resonant in our audible bass. Tell that to the guys who're blasting the neighborhood next time (so they can blast you))

The term 'wolf note' is also used to describe the effect of raising the pickups too high on an electric guitar. This causes the magnets in the pickup to interfere with the string's motion, causing strange effects, sometimes warbling and sometimes just dissonance. Thanks to sideways for the info in this paragraph

Conversely, there are null notes too. Notes that are much quieter than the others. Same idea with dampening, instead of resonance. Most guitars have one or two dead or null notes.

Magical Ideation Scale (thing) by Tato Tue Feb 22 2005 at 5:13:49

linked by redbaker

Schizophrenia is a continuum, and most of us are closer to the odd end than we might like to think. In fact, psychologists have long defined lots of behaviors and beliefs as “schizotypal,” meaning schizophrenia-prone, that many folks might not think twice about. One particular category of schizotypal beliefs is that of magical ideation.

As P.E. Meehl defined it in 1964, magical ideation is a “belief, quasi-belief, or semi-serious entertainment of the possibility that events which—according to causal concepts of this culture—cannot have a causal relation with each other, might somehow nevertheless do.”

Judging from e2’s magical content, I think we might skew high.

Psychologists hoping to identify such beliefs for research need a way to measure the degree of magical ideation, and in 1983 that's just what Mark Eckblad and Loren J. Chapman at the University of Wisconsin–Madison, did with their publication of “Magical Ideation as an Indicator of Schizotypy” in the Journal of Consulting and Clinical Psychology. They developed a test which could be administered to subjects to find out where on the spectrum they might sit between, say, Richard Dawkins and Stevie Nicks. They also iterated and tested their test to show that it reasonably predicts future psychosis. The test was replicated and validated in 1997 by researchers at the same university. It is still in use today as one of the most regarded tests for magical ideation, and has come to be known as the Magical Ideation Scale.

The 30-question questionnaire asks the subject to label each statement as true or false. Based on comparison to an answer sheet, subjects are given a scale from 0-30, with zero being Baywatch and 30 being Bewitched. In the original sample set, 0-3 was unusually linear. 4-12 was normal for males, and 4-15 was normal for females. Above that is considered unusually schizotypal.

I emailed the authors and asked permission to post the whole test, but I was asked not to, as publishing it here would lessen its validity as a tool. But following are a few examples that range between the odd to the extreme:

I might not be human

Horoscope

TV or radio broadcaster

reincarnation

In general, the questions aim to identify whether the subject experiences, through magical beliefs, one of the seven main schizophrenic dissociations:

Thought-broadcasting
Passivity (being directly controlled)
Auditory hallucinations
Thought-withdrawal (having thoughts removed from the head)
Aberrant beliefs
Visual Hallucinations
Thought-reading

I'm not a test designer, but the language of the questions is sometimes a little loose for my taste. Sometimes the statements seem like they were made negative just so there would be some false answers, and that makes those statements unnecessarily hard to consider. Sometimes the sloppy language makes the question not fit the true/false sort of answer. For example, I pride myself on being a very grounded person, yet I could interpret some of these questions in the schizotypal way. For instance, question #24 is clearly structured in an if-then fashion, and, if I accepted the protasis, then yes, the apodosis follows. But, outside of that question, I don't accept the protasis, so how should it be answered? Per the actual language or per my guess about the question's intention? There are lots of tricky issues of interpretation like this that you could levy on other questions as well. Fortunately, the test captures this “slop” with an average mean higher than 0, because it's all relative to cultural norms of the sample set. That's good, because it covers the looseness of language and cultural norms. But it feels a little unnerving to have such a relative scale on something as important as your connection to reality.

Even in Meehl's definition, "normal" magical ideation and schizotypy are defined by the context, and that changes with geography, time, and subculture. For example, in the original report Eckblad and Chapman arbitrarily excuse their own culture when defining "passivity experiences". They describe these experiences as "ranging from a subject's belief that a person or force other than God, the devil, an angel, or spirits seized control of his or her body or mind..." (Italics my own.) From naturalist perspective, there's no reason to excuse these agents at all. Possession by "the devil" seems just as out of touch with reality as possession by a dryad or a Martian.

So, yes, the edges of "in touch with reality" and "looney tunes" are a little muddy, but if psychologists are going to study these things, they have to start somewhere. And until someone comes up with a better test than this, this is how we'll be measuring up.

Sources

Meehl, P.E. Manual for use with checklist of schizotypic signs. Unpublished manuscript, University of Minnesota, 1964
Eckblad, M. & Chapman, L. J. (1983). Magical ideation as an indicator of schizotypy. Journal of Consulting and Clinical Psychology, 95, 111-125.
~~To get a copy of the test (and the answer key) contact the American Psychological Association at http://www.apa.org/~~
(Apparently the APA has taken it down from their site. Now I don't know where you can get a copy, other than me.)

carrier wave (idea) by redbaker Fri Jan 14 2005 at 10:28:31

linked by Oolong

Say you want to send a message out on the airwaves. How do you do it? Well, sound is a wave, right? And radio is a wave too, right? So why not just convert the sound waves of your message directly into radio waves and broadcast that signal? There are a couple of problems with that. The human ear can hear sounds ranging in frequency from 20 Hz to 20,000 Hz. This means that your signal will have a similar range. But where in that range will it fall? As it turns out, it'll be all over the place, unless you plan on sending out A above middle C all day. The waveform of a human voice looks something like this:

 . . . .. .. '    . .!    . .(.   . .7,   . .=*   . .¦¦   . .!(   . .!(   . .!(   . .!(   . .!'*  . .! (  . .! (  . .! (  . . ''  .! (  . ¦ *¦  .! ¦. . 7* **!,.! ,* ..7*   ( *,,*.* '!..!!*   ( *,,*.!  !..('*   ( '*!'        *,,*.!  ,*.(.!.  ( ******' *,        *,'*'!   ¦.(  .! ( '!        *' !'! !'      .!  !,! .!.     '!  !,!   .¦!'   ¦,* .!.    !.  !,!   .(! .,'  .¦   !,!   .=' *' !'   !,!   .! ,*¦.   **!    . ..     =!    . ¦!    . .!    . .,    . . . . .. . . . . . . . . . . . . . . . . . . ............................. . . . . .  /well-defined" title="well-defined" class='populated' >well-defined frequency there.  It changes with time.  And it's pretty hard to tune your radio to a signal with a frequency that is changing drastically all the time.  Moreover, these are fairly low frequencies, at least when we're talking about radio signals.  It's hard to get an antenna to transmit at 20,000 Hz, much less 20 Hz.  So what's the solution?  Use a carrier wave.  A carrier wave is a wave with a frequency far higher than that of the signal (and I mean far higher — for AM radio, frequencies around one million Hz are often used!) which is used to transmit the signal.  This is done through the process of modulation.  Modulation is, in essence, a process in which a certain property of the carrier wave is multiplied by the signal.  It's...well, perhaps we'd be better off with some pictures at this point.  Say that this is the signal that we want to send:

                                          .
                                                 .',!¦=CJC7=7JJCC=¦!'.
                                              .,¦7CC=!,'........,!¦=C7¦*'.
                                           '*=CC(!'                 .,¦=7C=,.
                                        .,(CC(*.                       .'*=7=*'.
                                      .!7J7!'                              '¦7C=*.
                                    .¦JC¦,.                                  .,¦CC*.
                                  .!3J!.                                        '¦3C*.
                                '!JC¦.                                            '¦CC!'
                              .!CJ¦.                                                .!JC!.
                            .!7C¦'                                                    '!CC*.
                           'J3¦'                                                        ,(C7'
                         '¦$¦'                                                            '(37,
                       .¦JJ!                                                                ,=J¦.
                     .*7J!                                                                    ,7C¦'                                                                            ..
                    .(J7,                                                                      .!77*.                                                                        .,(*
                    '¦,.                                                                         .!7=*                                                                      '=3('
                                                                                                   '¦7=*.                                                                 '!77!.
                                                                                                     .!J7,                                                              .!JC!.
                                                                                                       '¦C(,.                                                         .*JJ!.
                                                                                                         '(7('                                                      .*=3('
                                                                                                           '(C(,.                                                 .*CJ¦'
                                                                                                            .*=C=,                                               ,7J=,
                                                                                                               '¦CC!.                                         .!7C(,
                                                                                                                 ,(JC!.                                     .*C3(,.
                                                                                                                   .*=C=*.                               .*=JJ,
                                                                                                                      '(CC(,.                         .,(JJ=,.
                                                                                                                        .*=C7(!,.                 .'*(CJ7!.
                                                                                                                          .'*!(7=(!*,'..    .'',!(77=(!'.
                                                                                                                              .',!(7====(((¦===((¦*'.
                                                                                                                                   ...'',,,,'...
                                                                                                                                                                            ..

And say this is our carrier wave:^*


                      ..      .'    . .'      '.      ''      ,'     .,'     .,'     .*'     .,'     .!,     .!,     .!,     .(*     '¦,     '¦,     '7,     ,(,     '(*     'C,
                      7C.    .=J,    .JJ.    .CC.    'C7.    'AC     ,$=.    ,AJ.    ,A7     ,$C.    '5J.    *57     *AC.    ,@J.    (#7.    ¦57     !M7     =#=.    ¦#7     !W7
                     .AÐ'    '$#!    'Ð@*    ,5#'    *#A,    *M5.    ¦@$'    *ÐA,    ,Ð#     ¦@%,    ,ÐA'    !Ð5.    (Ð%,    *W%.    C@3.   .=Ð3.    (W$.   .C@C.   .=ÐJ.    ¦@3
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                     !%%=    *7%7.   'AJ(    =35!   .¦33(    (J$,   .73$*   .¦33¦    ¦7A'   .=7C!    ¦JC¦    ==%'   .=JC!    CC3,    C7$'   '=3J*   .3!5,   .7C3,   '7JJ*    J!#'
                     ¦JJC    ¦C37.   *3=7    ==$(   .=JJ7    77J¦   .=(J!   .7CJ7    C¦J!   .=(7¦   .=C77    7¦J!   .=7C¦    3=7!   .3(3,   '=7C!   .$!A!   'C=J,   '=(C¦   .3*5,
                     ¦7¦%.   ¦=77'   !7¦C    C(3C.  'C7C7    3===   .7(J¦.  .7=77    J!7!   .7(C(.   (=(7    J¦7¦   '7=J=.  .3!=7   'C!J*   ,7¦7¦   ,%'J¦   ,C¦J!   'C!7¦   ,3'J*
                     =(*A.  .(=!('   (7!3'   J¦7J.  'J===.  .$¦7J.  '7!C=.  '7(=C   .J*7C   '=!(¦.  .C(¦=   .J*=C   ,=!C=.  'A*=7   ,C*J¦   ,7*=(   *A'C(   !C*J¦.  ,J,=(   ,3'C¦
                     7(,A.  .(=¦7,   J(!3'  .C¦!J.  '3=(7.  '$,=3.  '7!==.  'C!7J.  'J,(C   '7!¦¦.  .C,¦7.  '3*(C   ,7!=7'  '$,=J   !C,C(   *J,7=.  !A'C=   ¦C*J=.  ,3,==   ,J.=7
                     J('5'  .((!C*   3(,3,  .J¦,3.  ,J¦(C'  '$,¦A'  *7*(7.  'J,¦C'  '3,,3.  ,=*!='  .C'*7'  'J**$.  *C*(='  '%'(J   ¦C,¦=   *J'==.  !J.77   ¦='77.  '7.=7.  !J.!7
                     C¦.%,  .==,7*  .$!,3!  .J¦,A.  ,3!¦7,  *%'*%'  *7*!J'  ,$'!7'  *3'.$.  ,=**7'  '3.*C,  !C',%.  *C*!7'  ,5.!C.  (7'!J.  *J'(=.  ¦$.¦J.  ((.=7.  ,C.¦=.  ¦J.*C
                     3¦.C*  '7('J(. .%*'C!  'J!'A'  ,$*!3!  !A.'$,  !C*,C'  ,3.!J*  !3..%'  *7,,C,  '$ *J!  ¦J'.$.  !J,!C,  ,% *J,  (7'*3.  ¦C.¦='  ¦J !J.  (7'!C.  !J.¦='  ¦7.*3.
                    '3¦.J(  '=¦.C(. .%*.(¦  *C*.%!  ,J,*J!  !%.'$*  ¦7,,$,  ,3.!J!  !J..$,  !C,,3*  ,% ,C!  !C' 3'  !J'!3*  *$ ,J,  ¦(.,$. .¦C.¦C,  ¦C ,J'  (=.*C.  !C.¦C,  (=.,$'
                    .3! CC  ,7! 7=. .$'.==  *C* J=  *$''C(  *$.'$!  ¦C,.J,  *3.,J(  *=..3,  ¦C,'J*  *% 'C(  !7' $,  !J,*J!  !C 'C!  =(.'5' .(3.!C*  C( ,3,  ((.,3'  !J.!7,  7( .3'
                    '3! =J  ,C! =7' '$..=J  !C, C=  *%'.C=. !3..C=  ¦7'.J*  !%.'C=  ¦=. 7¦  !C,.C¦. *A..==  (C' C¦  *7''C¦  !C '=¦ .7=..%* .77 ,C!  == '3* .=¦.'3'  !7 ,7!  7=..3,
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                    ,J* ,$. *J, ¦=' ,$  !C. ¦C, =C  !3. ==. (= .=J .(=. J( .=C  (=. =C. (7  ¦=. (¦. (C  ¦=  (7' (C  ¦7. 7(. ¦J .¦( .C¦ .$= .== '7¦  %¦ .=¦ 'C¦ .3! .7! '=¦  $! .=! .,'
                    .*. '$' !3, !7' *%  !J' ¦=' !J .($. (=' == .(3 .=(. ==..7C  (7. 7(. =J  ¦(. ¦=. (C  ¦=. 7=. *3 .¦=  ==. =C .(7 .J¦  J( .==  =(. $¦ .== 'J( .C! .7¦  ((. $! .== '=¦
                         %, *J, *C, !A  *C' (=' '$..¦C. ¦C, J=  ¦J..7=. ¦7. ¦=  ¦=' C¦. !J .¦(. ¦J' !=  !7' C=. ,3..(=  (7' =( .(C .J¦  (C '7¦  =(. $! .(7 'C¦  (= 'J¦  =7. J*  ¦7 ,C¦
                         $* !3, ,J* !$  ,C* ((. .5' !C. *7, C=  *3''C=. !J..(=  !=' C¦  ,3'.((  *J' ¦=  *='.C¦. '$'.==  ¦C' C¦ .¦7 'J¦  !J 'C*  ==' %! .¦7 ,7!  (C.'J,  (7. J*  != *C!
                         C! !J' 'J* *C  ,C! =='  5,.=7  *C* 7¦  *3,'C=  'J..J(  *=, J*  'J''7=  'J' J¦  *=,.3!  ,$''7=  *7' $*  !7.'C*  !3.'7,  ¦=''$,  !J.*7*  ¦J.'J,  !('.C'  ¦J.*7,
                         7! ¦C. 'J! !J  '7¦.7(.  A,.==  *J! 3¦  ,3*,J(  '$'.J!  !C* 3!  'J,'7(  '$' J¦  *C!.3¦  .3,'7¦  ,7'.$,  *C''J!  '%',J'  ¦7''$,  !C.*C*  ,C.,$.  !=''J,  !J.*7,
                         =C.¦7. .C¦.((  .¦('3(   A!.C=  ,C! $!  'J*,7!  'A'.3!  *C* J*  .7,,7¦  'A, 3!  ,7¦.C*   3,,7*  '3,.$,  ,=,,=,  .%'*3,  !J**3'  *C'*7,  'C.*$.  ¦J**J,  ,J'*=,
                         ¦J.¦7.  7=.7(  .¦='J(   $¦'J¦  '7!.3*  'C¦,7!  'A,'3,  '7!.C,  .=!'=!  .$,.3*  '7(.C*   J*,7*  .C,'%'  ,=**7,   A,*$'  *C*!3'  ,C,!=,  .$'*$   *=,!C'  ,J'!C'
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                         *3,7=   ¦7'3¦   ¦7*J¦   =3,J*  .7=*3,  .(7!C*   C¦,$'  .=(*C'  .¦=*7*   7¦,$'   (=*C*   (7,C,  .C¦¦%.  .¦(¦='   J!!$.  'C!=C.  .(¦¦='   $!!$   '7!(=.  .7!¦C.
                         ,$*J=   *C,$!   ¦3!C!   ¦3*$,   ((¦$,  .=J!C,   ==*%.   ((!C'   !7*7'   (=*$.   (7¦7,   ¦J*C'   =(¦A.   ¦7(7'   C=*J.  .7¦7C.  .¦=(=.   3¦¦3   .7=7=.  .((¦=.
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                         .=5%,   .C$%.   .=#3,    $%3    '35=.   'C%7.    $A=    ,CA¦.   'C%7.    3#C    'C5(.   .3ÐJ.   .3@(    ,3A(    'A#(    *5Ð!    *$%¦    .A@¦    !A@!    ,$%¦
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                          '7(     .C¦     '¦*     '7,     ,7,     '!'     '(.     ,('     '¦'     '!.     '*'     '!.     '*.     ',.     .,      ,,      .'      .'      .'      .'
                           ..      ..      .       .       .               .       .






Then this would then be the form of the signal that was actually sent out if the process of amplitude modulation were used to piggyback the signal on the carrier:

                                                                                                                                                                                         .
                                                      .,'     .J,     .*.
                                                      !%=     ,W7     ¦A¦
                                                      ¦@J.    !©C     =@=.
                                              '7!     !#3.    !©J     =Ð7.    ,7!
                                              *#C.    !#3'    =M%.    7ÐC.    ¦@C
                                              ,#%.   .(#3,    J$$'    =$C.    ¦Ð3      .
                                      .¦!     !#5.   .(A3*    JC$'    7%3'    ¦@J     .C,
                                      '5$.    !CA.   .¦$J*    C($,    CA5,   .¦AJ'    ,W=
                                      '55,    !C5.   .(JC!    C=$*    CJ$'   .¦$J'    *MC
                               .'     '@#*    ¦J#,   .=J7!   .3($*    7=3'   .¦3J*    *M$.
                              .CJ,    ,#A!    =C5,   .=CJ(   .$¦$!   .C(3'   .(JJ!    ,@A'    .¦*
                              .$5*    ,$J¦    (¦3!   .¦=C(   .3!=¦   'C(J'   .(CC!    (J$'    *AC.
                              .$#!    ,37(    7(J!   .¦(7(.   J'=¦   '7¦$!   '==C(    7C$'    ,AJ.
                       ''     ,%#!    ,3C7    C¦J=   '7(7=.  .3,=(   .C($!   '((C(    7(%*    ,5$'
                       C5.    *J%¦.   ¦J=7    C¦=J   '=!==.  .3,(J   .=!J¦   '7¦7=    C*3*    !A%,
                       3M,    *73(.   (J(C    J¦!J   '=¦==.  '%'¦J   '=*7=.  ,7*((    J*C!    !C$,     ..
                      .%W¦    !7J=.   ¦7!=    7!*J   '=¦7C'  'A.!C   '7*=(   ,C*==.   7,7(    (73*    'JC.
                      ,%$=    ¦(C7'   ¦7!C.   7!*3   '=!7C'  '%,!J   *C*=7.  '7*=7.   7'=(    ==C*    ,#A,                                                                     ¦'
                      ,$7J    ¦(=='   77*7'   7*'J   '(!(='  .$.!C   !7,(C.  '=,=7.  .J,(C    (¦C(.   ,A%*                                                                    ,Ð7
                      *J!C   .((!='   7(,C,  .C*.3.  ,7!!7,  .$ *C   ,7,,J.  '=,(7.  .C.¦=    ¦!C=.   *3C!                                                                    !WJ
                      *7,J.  .==*='   C7,7,  .C!.5'  *J**7,  .J ,J'  *C*'C.  ,C*¦7'  .J'!7    (¦==.  .¦C¦¦     '.                                                             !#%'
                      !7.3'  .==,C,   7¦,7!  .C!.A'  *3!*J!  .$ ,J*  ,7,'J.  ,C,!7,  .J.,7    =¦¦=.  .¦7(7    .$J.                                                     '.     =7$,
                      ¦7.3'  .=='C*   =!,C¦  .7, %,  ,J¦,7*  ,5 '7*  ,7,'3'  ,J,!C*  .J.'C    =¦!7.  .¦(¦=    ,#@'                                                    *$7.    J!3*
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Hopefully that gets the idea across.  Mind you, there are other kinds of modulation out there — amplitude modulation was just the first to be used, and when it comes to explaining what a carrier wave is, it's also the most pedagogically valuable.  The details of modulation are best left for another node.
^*NB: This is not to scale at all — carrier waves generally have wavelengths hundreds of times shorter than the signal they carry.

Clovis point (thing) by The Lush Sat Jan 15 2005 at 6:07:49

For those who play with rocks for a living...

What is a Clovis point?
It is a type of spear point created through a process known as bifacial pressure flaking. To get an idea of what a Clovis point looks like, picture in your mind, the familiar image of an arrowhead (forget that there are actually several forms). Now, take away the side notches, make the sides excurvate (curve outward), and make it somewhere in the neighborhood of 50mm - 74mm in length. Voila! You have done it, now you know what a Clovis looks like. The name Clovis comes from the location of the site were the first Clovis points were found, in Clovis, New Mexico (eastern part of the state, bordering Texas). They are generaly composed of flint or chert. Also, they are fluted, which means that they have a pointy-ish line running down the middle of them. Their base is concave, facilitating the process of hafting them to spears.
Who used them? How were they used?
Archaeologists believe that Clovis points are among the oldest projectile points used by the Paleo-indian peoples of North America, dating to the Early Paleo Period (15,000 B.P. - 9,000 B.P.). Clovis points were wedged into notches at the ends of spears and then hafted with cord (likely made with animal gut or plant materials). The finished spears could then be thrown at large game, or, for the more exceptional hunter, launched with a device known as an atlatl. It is a tube with a spur at one end (or something else to catch on the spear), and an opening and hand grip at the other end. The spear is loaded into the open end and catches on the spur. Holding onto the atlatl the entire time, the hunter may throw the spear with a slingshot like effect. In effect, the purpose of the atlatl is to lengthen the arm of the spearthrower, thus, increasing the power of the throw.
Further Thoughts
During this past semester, whilst in the midst of our lithics unit, our archaeology T.A. told us a little anecdote about Clovis points. Apparently, a few years back a farmer in the area of our our school (University of Missouri - Columbia) found a Clovis point in one of his fields. He was quite excited about his find and prepared it to be donated to the MU Museum of Archaeology. When the museum curator received the artifact, however, he was perturbed to find that it had been defiled. The farmer later admitted to busting out his Dremmel to grind side notches into the Clovis, "because it didn't look like how an arrowhead is supposed to."

Sources:

http://www.sdsmt.edu/wwwsarc/collectn/stone/clovis.html
Archaeology Classnotes 10/18

Simethicone (thing) by rootbeer277 Wed Mar 31 2004 at 23:24:41

linked by Serjeant's Muse

Also known under the trade names Phazyme and Mylicon.

Chemical formula:
(CH₃)₃SiO[Si(CH₃)₂O]_nSi(CH₃)₃ {n: 200 < n < 350}
The chemical chain [-Si(CH₃)₂O-]_n is called poly(dimethylsiloxane), and it is both literally and figuratively the backbone of the silicone industry. All silicones are formed around a chain of Si-O atoms, frequently with organic groups attached by an Si-C bond. PDMS is the most common example, and looks like this:

     H      H      H
     |      |      |
   H-C-H  H-C-H  H-C-H
     |      |      |
... -Si--O--Si--O--Si--O- ...
     |      |      |
   H-C-H  H-C-H  H-C-H
     |      |      |
     H      H      H

Simethicone is an over the counter drug (see note below) used as anti-gas medicine. It works by breaking down the surface tension which allows bubbles and foam to form, making it easier to pass the gas out of your system (it does not actually prevent gas, it just eases discomfort caused by gas). It is available in capsules or tablets (60-125mg), chewable tablets (40-125mg), or as a liquid suspension (40-95mg). Dosages for children should be determined by a doctor.

Medicine containing Simethicone should be stored in a tightly closed container, out of the light, and away from heat and moisture (that is, do not store in the bathroom). Simethicone is an active ingredient in a number of medicines, including:

Maalox
Flatulex
Gas-X
Genasyme
Mylanta
Phazyme
My Baby Gas Relief Drops
Mylicon Drops
Phazyme
Ovol (in Canada)

Simethicone is very safe, since it is not actually absorbed by the body. Missed dosages are not a significant problem, and overdoses are very unlikely to cause any serious harm. There are no known interactions with other drugs, food, or vitamins (although some people are allergic) and it is safe for pregnant and nursing mothers. It can be taken for long periods of time with no additional risks. Side effects, though rare, include bloating, constipation, diarrhea, gas, and heartburn.

My personal experience with Simethicone (in Mylanta) suggests that for best results, take the recommended dosage once about ten minutes before eating foods likely to cause gas problems.

Special thanks to vuo for pointing me to the information I needed on PDMS, and also for letting me know that Simethicone is not technically a drug since it is chemically inert and not absorbed by the body. Its physical properties as a surfactant (as opposed to chemical properties), however, are useful for controlling gas problems.

Sources:
http://www.gicare.com/pated/simethicone.htm
http://www.nlm.nih.gov/medlineplus/druginfo/medmaster/a682683.html
http://health.yahoo.com/health/drug/202522/overview
http://www.bnamericas.com/rc_search_detail.xsql?id_documento=30642&Tx_idioma=I&tipo=C
http://www.dowcorning.com/content/sitech/sitechbasics/silicones.asp

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