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Pouring oil on troubled waters ...

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1 Pouring oil on troubled waters ...
As early as the 9th Century BC, sponge divers would spread olive oil (containing the surfactant olive oil) on the water surface in attempt to reduce the irritating flickering due to surface ripples (Young, L.B. 1983; The Blue Planet. Little Brown and Co. Boston. See J.C. Scott’s paper on: “The Historical Development of Theories of Wave-Calming Using Oil” Rep. 81, University of Essex, Colchester, England (1977) In 1774, Benjamin Franklin read a paper to the Royal Society describing an experiment he performed on a half-acre pond where a tea spoon of oil, which was “very rough with wind”, became as “smooth as a looking glass.” Dr. Jim Rohr - SPAWAR Systems Center Pacific

2 Problem: increasing signal to noise of hydrophones
As early as the 9th Century BC, sponge divers would spread olive oil (containing the surfactant olive oil) on the water surface in attempt to reduce the irritating flickering due to surface ripples (Young, L.B. 1983; The Blue Planet. Little Brown and Co. Boston. See J.C. Scott’s paper on: “The Historical Development of Theories of Wave-Calming Using Oil” Rep. 81, University of Essex, Colchester, England (1977) Solution (?): reducing background noise Dr. Jim Rohr - SPAWAR Systems Center Pacific

3 Phenomenon: wine tears

4 how it works ( sort of ) less alcohol more alcohol The effect is a consequence of the fact that alcohol has a lower surface tension than water. If alcohol is mixed with water inhomogeneously, a region with a lower concentration of alcohol will pull on the surrounding fluid more strongly than a region with a higher alcohol concentration. The result is that the liquid tends to flow away from regions with higher alcohol concentration. This can be easily and strikingly demonstrated by spreading a thin film of water on a smooth surface and then allowing a drop of alcohol to fall on the center of the film. The liquid will rush out of the region where the drop of alcohol fell. Wine is mostly a mixture of alcohol and water, with dissolved sugars, acids, colourants and flavourants. Where the surface of the wine meets the side of the glass, capillary action makes the liquid climb the side of the glass. As it does so, both alcohol and water evaporate from the rising film, but the alcohol evaporates faster, due to its higher vapor pressure. The resulting decrease in the concentration of alcohol causes the surface tension of the liquid to increase, and this causes more liquid to be drawn up from the bulk of the wine, which has a lower surface tension because of its higher alcohol content. The wine moves up the side of the glass and forms droplets that fall back under their own weight. The phenomenon was first correctly explained by physicist James Thomson, the elder brother of Lord Kelvin, in It is an instance of what is today called the Marangoni effect (or the Gibbs-Marangoni effect): the flow of liquid caused by surface tension gradients. It is sometimes claimed incorrectly that wine with "lots of legs" is sweeter or of a better quality. In fact the intensity of this phenomenon depends only on alcohol content, and it can be eliminated completely by covering the wine glass (which stops the evaporation of the alcohol). On certain curious motions observable at the surfaces of wine and other alcoholic liquors ~ James Thompson

5 how it works Oleic acid (olive oil) composed of both hydrophilic and hydrophobic ends. A I R W A T E R

6 OIL CONCENTRATION DECREASING AT SURFACE SO SURFACE TENTION INCREASING
Air Water OIL CONCENTRATION INCREASING AT SURFACE SO SURFACE TENTION DECREASING

7

8 Fourier Analysis is important many branches of physics: heat conduction, light diffraction, wave propagation, musical sound, etc. First and foremost, a Fourier transform of a signal tells you what frequencies are present in your signal and in what proportions. Example of how can use: If you're a football (soccer) fan, you might've been annoyed at the constant drone of the vuvuzelas that pretty much drowned all the commentary during the 2010 world cup in South Africa. However, the vuvuzela has a constant pitch of ~235Hz which made it easy for broadcasters to implement a notch filter to cut-off the offending noise.[1st and foremost, a Fourier transform of a signal tells you what frequencies are present in your signal and in what proportions. Can use to estimate height from voice by determining fundamental formants and estimate of resonating chambers in head. Elementary book on Fourier analysis: Who is Fourier ? A mathematical Adventure Translational College of LEX, Language Research Foundation, Boston

9 No effect at low ? frequencies ?
Fourier Analysis is important many branches of physics: heat conduction, light diffraction, wave propagation, musical sound, etc. First and foremost, a Fourier transform of a signal tells you what frequencies are present in your signal and in what proportions. Example of how can use: If you're a football (soccer) fan, you might've been annoyed at the constant drone of the vuvuzelas that pretty much drowned all the commentary during the 2010 world cup in South Africa. However, the vuvuzela has a constant pitch of ~235Hz which made it easy for broadcasters to implement a notch filter to cut-off the offending noise.[1st and foremost, a Fourier transform of a signal tells you what frequencies are present in your signal and in what proportions. Can use to estimate height from voice by determining fundamental formants and estimate of resonating chambers in head. Elementary book on Fourier analysis: Who is Fourier ? A mathematical Adventure Translational College of LEX, Language Research Foundation, Boston ?

10 ? -5 to –6 dB per octave from 500 to 20,000 Hz

11 “I want to know what it says…the sea…
what it is that it keeps on saying” – Charles Dickens

12 Synoptic Surface Noise Instrument
Floats about 1 m below surface, takes video of surface events while recording sound.

13 PRIOR TO SPREADING OF SLICK
NO MICRO-BREAKING WITHIN FILM OF MONOMOLECULAR OIL (oleic acid)

14 Sound associated with micro-breaking… but how?

15 Birth of a bubble!

16 On the Musical Air-Bubbles and Sounds of Running Water – M
On the Musical Air-Bubbles and Sounds of Running Water – M. Minnaert 1933 An explanation for “the murmur of the brook, the roar of the cataract, or the humming of the sea”. Air bubble of 1 mm in radius Resonant frequency of about 3300 Hz An explanation for “the murmur of the brook, the roar of the cataract, or the humming of the sea”.

17 Drop Creating Bubble

18 Symbols: my data Lines: boundary for bubble production from literature
Drop Height (cm) Probability that an individual drop will produce a bubble decreases linerly from 100% at normal incidence to 10% for oblique incidence 20o from vertical (Nystruen) Drop Diameter (cm)

19 Bubbles produced by breaking/spilling waves
and associated spray Film bubble No Film impact

20 University of Cambridge, England
THE END Rohr, Glass and Castille – Effect of Monomolecular Films on the Underlying Ocean Ambient-Noise Field J. Acoust. Soc. Am. 85, (1989) Rohr and Detsch – A low sea-state study of the quieting effect of monomolecular films on the underlying ambient-noise field J. Acoust. Soc. Am. 92 (1), (1992) Rohr and Updegraff in Natural Physical Sources of Underwater Sound, B. R. Kerman (ed.) Kluwer Academic Publishers University of Cambridge, England

21 Olympic Excellence (number of medals)
#1 #1 - #1 #1 #2 #3 #1 #2 #2 #1 #1 …. in science H.S. students - #17th in math H.S. students - #24th I could not begin to imagine the reaction that would follow if our world ranking fell to 17th or 24th. And yet, that is precisely where our high school students respectively rank internationally in science and math. We also rank 27th (out of 29) for the rate of STEM (science, technology, engineering and mathematics) degrees awarded in developed countries. In engineering 6% of our undergraduates major in engineering, 12% in Europe, 20% in Singapore, 40% in China rate of STEM degrees 27th (out of 29) 21 21

22 In this country we honor engineers as movie stars
and action heroes Homer Simpson first appeared on TV in 1987, his series started on Channel 4 viewers voted him the greatest TV character of all time.

23 thinking outside the box
Draw four straight lines to connect all the dots. You can not take your pencil off the paper. It has been suggested that the term “thinking outside the box” comes from this puzzle. In one 6th grade class a young girl sheepishly stated that she could satisfy the requirements in one stroke! One line! I never specified how thick the line had to be. Another imaginative solution was to place the dots so close to each other that one line will pass through them! Puzzles are in all cultures throughout time... And the 9 Dot puzzle is as old as the hills. Even though it appears in Sam Loyd’s 1914 “Cyclopedia of Puzzles”, the Nine Dot puzzle existed long before Loyd under many variants. In fact, such a puzzle belongs to the large labyrinth games family. 9 Dot puzzle is also a very well known problem used by many psychologists, philosophers and authors (Paul Watzlawick, Richard Mayer, Norman Maier, James Adams, Victor Papanek...) to explain the mechanism of ‘unblocking’ the mind in problem solving activities. It is probable that this brainteaser gave origin to the expression ‘thinking outside the box’. The most frequent difficulty people encounter with this puzzle is that they tend to join up the dots as if they were located on the perimeter (boundary) of an imaginary square, because:   - they assume a boundary exists since there are no dots to join a line to outside the puzzle.   - it is implicitly presumed that tracing out lines outside the ‘invisible’ boundary is outside the scope of the problem.   - they are so close to doing it that they keep trying the same way but harder.Unfortunately, repeating the same wrong process again and again with more dynamism doesn’t work... No matter how many times they try to draw four straight lines without lifting the pencil. A dot is always left over! “A wonderful old expression calls creativity “a fine madness” and it is. Invention lies outside the common ways and means. If it is sane to respond predictably to reality, then invention surely is madness. A well-known riddle shows us something of the way that madness works. You are asked to connect nine dots, in a square array, with four straight lines. Each line has to continue from the end of the last line. The problem seems at first to have no solution.

24 ! TO THINK OUTSIDE THE BOX…
Draw four straight lines to connect all the dots. Each line must start from the end of the last line. ! “The trick, of course, is to walk around accepted limitations. Once we recognize that lines need not conform to the square space suggested by the dots, we can solve the problem.” Thinking outside the box (sometimes erroneously called "thinking out of the box" or "thinking outside the square") is to think differently, unconventionally or from a new perspective. This phrase often refers to novel, creative and smart thinking. The origin of the phrase is somewhat obscure. John Adair claims to have introduced the problem in 1969[1]. Management consultant Mike Vance has claimed that the use of the nine-dot puzzle in consultancy circles stems from the corporate culture of the Walt Disney Company, where the puzzle was used in-house.[2] Both Martin Kihn of Fast Company[3] and the Random House Word Mavens[4] agree that the phrase relates to a traditional topographical puzzle called the nine dots puzzle. According to consultants of the 1970s and 1980s tried to make their prospective clients feel inferior by presenting them with the puzzle. The challenge is to connect the dots by drawing four straight, continuous lines that pass through each of the nine dots, and never lifting the pencil from the paper. The puzzle is easily solved but only if you draw the lines outside the confines of the square area defined by the nine dots themselves. Thus, the phrase "thinking outside the box" was born. The Word Mavens refer to Prof. Daniel Kies of the College of DuPage, who observes that the puzzle only seems difficult because "we imagine a boundary around the edge of the dot array."[5] The nine dots puzzle is much older than the slogan. It appears in Sam Loyd's 1914 Cyclopedia of Puzzles.[6] In the 1951 compilation The Puzzle-Mine: Puzzles Collected from the Works of the Late Henry Ernest Dudeney, the puzzle is attributed to Dudeney himself.[7] Sam Loyd's original formulation of the puzzle[8] called it "Christopher Columbus's egg puzzle." as an allusion to the story of Egg of Columbus. Christopher Columbus's Egg Puzzle as it appeared in Sam Loyd's Cyclopedia of Puzzles. The Columbus story may have originated with Italian historian and traveler Girolamo Benzoni. In his book , published in 1565,[2] he wrote: Columbus was dining with many Spanish nobles when one of them said: 'Sir Christopher, even if your lordship had not discovered the Indies, there would have been, here in Spain which is a country abundant with great men knowledgeable in cosmography and literature, one who would have started a similar adventure with the same result.' Columbus did not respond to these words but asked for a whole egg to be brought to him. He placed it on the table and said: 'My lords, I will lay a wager with any of you that you are unable to make this egg stand on its end like I will do without any kind of help or aid.' They all tried without success and when the egg returned to Columbus, he tapped it gently on the table breaking it slightly and, with this, the egg stood on its end. All those present were confounded and understood what he meant: that once the feat has been done, anyone knows how to do it. “A Fine Madness”

25 ? ONE STRAIGHT LINE? (make line sufficiently thick)
This solution to the 9-dot puzzle was offered by a 3rd grader during my presentation. She raised her hand and sheepishly said “I think I can solve the puzzle with ONE line”. I told her the line has to be STRAIGHT, NO TAKING PENCIL OFF THE PAPER. Up goes her hand – “yes, I think I can solve the puzzle with one straight line, not taking my pencil off the paper”. I said incredulously, well OK, how? She simply drew one straight, VERY THICK line! I never said how thin the line had to be. (make line sufficiently thick)

26 ONE STRAIGHT LINE! OR THREE!
This solution to the 9-dot puzzle was offered by a 3rd grader during my presentation. She raised her hand and sheepishly said “I think I can solve the puzzle with ONE line”. I told her the line has to be STRAIGHT, NO TAKING PENCIL OFF THE PAPER. Up goes her hand – “yes, I think I can solve the puzzle with one straight line, not taking my pencil off the paper”. I said incredulously, well OK, how? She simply drew one straight, VERY THICK line! I never said how thin the line had to be.

27 Minimum number of straight lines without taking pencil off of paper
For an older audience, perhaps a little more math orientated, you might add this. The point is that mathematicians are interested in these type of puzzles.

28 Minimum of 6 lines are required!
Excluding rotations and reflections there are 15 possible solutions For n x n square there are a minimum of 2n-2 lines required 6 lines are required, at a minimum, to solve the Sixteen Dot puzzle. Unlike the 9 Dot puzzle, this variant has 15 possible solutions (excluding compositions obtained by rotation and reflection). Since 6 straight lines are needed for this variant of the 9 Dot puzzle, then, how many straight lines would you need to solve the Twenty-Five Dot variant? Exactly 8 lines (you can try to solve this problem by yourself). Is there some general formula to find the minimum number of lines for a given number of dots? By making the Nine Dot puzzle as complex as we desire (exponentially increasing the number of dots to 25, 36, 49, 64, etc.), the following pattern appears to emerge through inspection: No. of DotsRequired Straight Lines 3 x 3 4 x 4 5 x 5 6 x 6 … (3 + 1) = 4 (4 + 2) = 6 (5 + 3) = 8 (6 + 4) = 10 … n + (n-2) = 2n -2

29 Education “ To Lead Out” Educere
Here I talk about how the word education is derived from the Latin word “educere” or “to lead out.” I talk about how all the books that they learn from exist in our offices and libraries. So what we need, is for them not to be able to regurgitate the material, but to understand it and more importantly, to use it in innovative ways.

30 Ingenium mental power “engine” related to: “ingenuity”
Is a Latin word that means mental power related to: “ingenuity” “engine” (14) Here I ask middle school students to give examples of engineers – most often the replies are “someone who drives a train.” So I say “Before Disney’s Imagineers, there were the Middle Age Ingeniators. P.S. The word “science” comes from the Latin word scienta, which means knowledge. Curiously, the word scientist did not appear to 1840.” engineer = “wild for adventure, keen for achievement, eager, ardent, bronze-faced, and keen-eyed” … someone who “had been seized by the spirit of some great thing to be.” - Zane Grey In The U. P. Trail See “INGENIUM – Five Machines that Changed the World” by Mark Denny Or “THE ENGINES OF OUR INGENUITY” by John Lienhard – for good background stories. In Medieval times ingenium referred to an “ingenious contrivance” and was often associated with siege engines such as the trebuchet; the crew who worked on these devices were ingeniators

31 Why do engineers innovate???
WHY DO ENGINEERS – ENGINEER? Why do engineers innovate??? “To the engineer falls the job of clothing the bare bones of science with life, comfort, and hope.” - Herbert Hoover The Grand Engineering Challenges: prepared by the U.S. National Academy of Engineering * Make solar energy economical * Provide energy from fusion * Develop carbon sequestration methods * Manage the nitrogen cycle * Provide access to clean water * Restore and improve urban infrastructure * Advance health informatics * Engineer better medicines * Reverse-engineer the brain * Prevent nuclear terror * Secure cyberspace * Enhance virtual reality * Advance personalized learning * Engineer the tools of scientific discovery Here I ask middle school students to give examples of engineers – most often the replies are “someone who drives a train.” So I say “Before Disney’s Imagineers, there were the Middle Age Ingeniators. P.S. The word “science” comes from the Latin word scienta, which means knowledge. Curiously, the word scientist did not appear to 1840.” engineer = “wild for adventure, keen for achievement, eager, ardent, bronze-faced, and keen-eyed” … someone who “had been seized by the spirit of some great thing to be.” - Zane Grey In The U. P. Trail See “INGENIUM – Five Machines that Changed the World” by Mark Denny Or “THE ENGINES OF OUR INGENUITY” by John Lienhard – for good background stories.

32 Thinking Outside the Box
Does Air Have Weight? while working inside the JAR

33 “We live submerged at the bottom
Does air have weight? in 1cm2 x 30km box ~ 1kg mass ~ 10N/cm2 Ninety nine percent of the atmosphere is below an altitude of about 30 kilometers. Compared with EArth's radius, Earth's atmosphere is just a thin shell. Earth's Atmosphere consists of gases built up from billions of years of volcanic eruptions mixed with suspended liquid and solid particles such as water droplets, ice crystals and dust particles. Gravity holds our atmosphere in place while differential solar heating reaching a tilted rotating sphere makes for an active and interesting system uniquely capable of supporting life on Earth. The Earth's atmosphere is more than just the air we breathe. It's also a buffer that keeps us from being peppered by meteorites, a screen against deadly radiation, and the reason radio waves can be bounced for long distances around the planet. The air that accomplishes all of this is composed of five major layers. The lowest is the troposphere, which is the layer that provides most of our weather. It contains about four-fifths of the Earth's air, but extends only to a height of about 11 miles (17 kilometers) at the Equator and somewhat less at the Poles. The name comes from a Greek word that refers to mixing. And mixing is exactly what happens within the troposphere, as warm air rises to form clouds, rain falls, and winds stir the lands below. Typically, the higher you go in the troposphere, the colder it gets. A Newton can be seen to be the force required to accelerate 1 kg of mass at 1 m/s2. To accelerate a 1 kg mass at 9.8 m/s2 would require 9.8 newtons, so on Earth the weight of 1 kg is 9.8 newtons. Similarly, a pound can be seen to be the force required to accelerate 1 slug of mass at 1 ft/s2. Since the acceleration of gravity in US common units is 32.2 ft/s2, it follows that the weight of one slug is 32.2 pounds. How much does a cloud weigh? Do you think clouds have any weight? How can they, if they are floating in the air like a balloon filled with helium? If you tie a helium balloon to a kitchen scale it won't register any weight, so why should a cloud? To answer this question, let me ask if you think air has any weight—that is really the important question. If you know what air pressure and a barometer are, then you know that air does have weight. At sea level, the weight (pressure) of air is about 14 ½ pounds per square inch (1 kilogram per square centimeter). Since air has weight it must also have density, which is the weight for a chosen volume, such as a cubic inch or cubic meter. If clouds are made up of particles, then they must have weight and density. The key to why clouds float is that the density of the same volume of cloud material is less than the density of the same amount of dry air. Just as oil floats on water because it is less dense, clouds float on air because the moist air in clouds is less dense than dry air. We still need to answer the question of how much a cloud weighs. For an example, let's use your basic "everyday" cloud—the cumulus cloud with a volume of about 1 cubic kilometer (km) located about 2 km above the ground. In other words, it is a cube about 1 km on each side. The National Oceanic and Atmospheric Administration (NOAA) provides some estimates of air and cloud density and weight. NOAA found that dry air has a density of about kilograms/cubic meter (kg/m3) and the density of the actual cloud droplets is about kg/m3. In the final calculations, the 1 km3 cumulus cloud weighs a whopping billion pounds (1.003 billion kilograms)! However, remember that air also has mass, so the cloud floats because the weight of the same volume of dry air is even more, about billion pounds (1.007 billion kilograms). So, it is the lesser density of the cloud that allows it to float on the dryer and more-dense air. per inch2 “We live submerged at the bottom of an ocean of air” Torricelli

34 Difference ~ 0.223 grams; Volume ~ 225 cm3;
The design of the vacuum pump (syringe) is similar in principle to the Hooke’s original except a valve was manually opened and closed between plunges of the piston, whereas we are now using two check valves which only lets the air move one way. Drawing the syringe out some of the air in the bell jar moves through check valve (A) to occupy the space in the syringe; check valve (B) is closed. When we push the syringe in check valve (A) closes and the air in the syringe moves out through check valve (B) to the room. Every time we go through this procedure (pushing in and pulling out), we remove a little more of the air in the bell jar. Notice it get harder to pull the syringe out – this is because the difference in pressures within and outside the bell jar is increasing. What does a cubic foot of air weigh? Given some data and making a few assumptions we can come to an answer that is probably pretty close. First of all, we need to know the composition of air. What is air made of and how much is it made of. A quick internet search popped up which gives us something to work with. (For those unfamiliar with the site's punctuation, a comma "," is used instead of a period "." a decimal delineation mark). This breakdown is actually greatly affected by where we are in the world and how far we are above sea level and other factors. We will assume average composition at sea level at 0 degrees Celsius which is known as STP or Standard Temperature and Pressure. For reasons that should become clear a bit later, we need the volume of the various components, not the weight. This is the composition of air (as cited from the website above) by volume: Oxygen: 20.99% Nitrogen: 78.03% Carbon Dioxide: 0.03% Hydrogen: % Argon: 0.93% Neon: % Helium: % Krypton: % Xenon: % There is a neat property that applies to any gas that a 22.4 liters of it at STP (standard temperature and pressure) contains x10^23 molecules of said gas. This amount (Avogadro's number) is called a mole. So another way to say this is that a single mole of gas at STP will fill 22.4 liters. The special thing about a mole is that a if we have a molecule, we can find that molecule's molecular weight (from a periodic table) and that's how many grams a mole of the molecule would weigh. For instance, if we were to look up iron (Fe) on a periodic table, we find that its atomic weight is A mole of iron is therefore grams. Quick conversion of 1 cubic foot to liters gives us liters. Going back we can take this number to find that liters of gas at STP is going to be moles of air. Great, we can now determine how many moles of each particular substance we have from the percentage composition of air. These are the results (and the molecular symbol for each): Oxygen (O2): moles Nitrogen (N2): moles Carbon Dioxide (CO2): moles Hydrogen (H2): moles Argon (Ar): moles Neon (Ne): moles Helium (He): moles Krypton (Kr): moles Xenon (Xe): moles By looking on the periodic table for the atomic weight of constituent atoms in the above molecules (for instance CO2 we would get the weight for C and add to it twice the weight of O) and multiplying by the number of moles we have of these substances, we will get the following weights for the substances: Note: After rounding errors and such, our current accuracy is such that anything less than 0.01g is insignificant and I have left those numbers out. Oxygen: 8.49g Nitrogen: 27.63g Carbon Dioxide: 0.02g Argon: 0.47g Adding these numbers together (remember the rest was insignificant) we get 36.61g. Converting to pounds (since the question was in English units I assume the answer is desired in English units) we get lbs. 1 cubic foot of air at standard temperature and pressure assuming average composition weighs approximately lbs. air inside bell jar air pumped out Difference ~ grams; Volume ~ 225 cm3; (~75% of air removed)

35 Robert Boyle Does suction “pull” or does outside atmosphere push?
(1627 – 1691) father of modern chemistry Does suction “pull” or does outside atmosphere push?

36 1 Build it! 3 Do suction cups suck?

37 What do you think happens to a balloon?
Before After What do you think happens to a balloon?

38 What do you think happens to a marshmallow?

39 What do you think happens to water ?

40 Boiling water by reducing ambient pressure,
Water boils when its saturated vapor pressure is equal to the atmospheric pressure 1 atm is kPa. Boiling water by reducing ambient pressure, boiling actually reduces temperature

41 Robert Boyle why is everything dying? (1627 – 1691)
father of modern chemistry pumped out air and showed it was the atmospheric supporting column can I produce sound? can a bumble bee fly? why is everything dying? can a bird fly?

42 “comes great responsibility” - ???
“with great power… “comes great responsibility” - ??? An Experiment with a Bird in an Air Pump ~ Joseph Wright 1768 42

43 “with great power comes great responsibility” – Uncle Ben
Uncle Ben first appeared in Amazing Fantasy #15 (August 1962) and was killed in the very same issue. Although his history as a supporting character was very brief, Uncle Ben is an overshadowing figure in Spider-Man’s life, “with great power comes great responsibility” – Uncle Ben

44 THE END (57) Please feel free to add some out-of-the-box thinking associated with your work or profession. June 2010 This presentation was created by: James Rohr, director Educational Outreach Programs SSC Pacific San Diego phone: (619)


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