Data is abstract

Take a hard disk. Print it out on a sheet of paper. It's just a long string of bits. The processor does nothing but shuffle around these bits, using some of the bits to interpret the other bits.

DNA is the same; instructions to build proteins to build cells and build more DNA.

The interesting parts are the concrete details; what kind of machine gets built. And they're not really in there; looking at machine will tell you what kinds of instructions there are, but not how to interpret them.

Teeth Care

(There are highly-abbreviated notes loosely based on "Kiss Your Dentist Goodbye". Read the book or google for clarifying details.)

• Tooth decay could be called an epidemic 
• widespread, not really treated
• almost all adults, even those flossing regularly, eventually get dental disease
• 1/5 Americans rate dental health as fair to poor
• 1/4 of young people have gum disease
• tooth decay 5x more common than asthma in childhood
• All sorts of diseases have been linked to it: cancer, acid reflux, heart problems, high blood pressure, stroke, insulin instability, infertility, premature birth, pancreatic cancer, bowel problems.
• Health care systems mostly suck, incentivize expensive treatments instead of prevention - good for research (and researchers), bad for the people involved

Identifying a good dentist

Despite name of the book (implying that you never need see your dentist again), she's a dentist and still recommends you see one occasionally.

A good dentist:

• prevents problems, avoids drilling; if treatment is necessary, chooses minimally invasive procedure
• avoids the common error of filling a perfectly sound tooth
• Identifies fillings when damaged by acidity (tooth around it erodes, comes loose) - can offer array of options, avoids using toxic chemicals such as mercury
• ideally: screens to help you prevent cavities, does not handle treatments or fillings directly (thus no conflict of interest)
• compare "drill, fill, cover" vs. leaving it in place and covering w/ porcelain pastes
• is skeptical of industry claims, communicative, source of info, experienced, knowledgeable, caring, effective, etc.
• believes in prevention, remineralization
• "mouth fitness trainer"
• interviews patients regularly to discover cause of dental damage
• has special equipment
• ultrasound depth testing, Inspektor dental light, digital imaging fiber-optic trans-illumination (DIFOTI), DIAGNOdent laser (kavo usa), inspektorpro, x-rays, ...
• see cavities, weakened areas
• measure tooth strength/thickness
• see at regular intervals
• provides advance warning/praise
• uses blunt instrument to check for rough spots, not explorer - see article "Should a Dental Explorer be Used to Probe Suspected Carious Lesions?"
• explorer - pushing sharp point into weakened area makes it harder for tooth to repair itself
• sticky spots not reliable diagnosis for cavity - only 24/100 w/ cavity in one study
• hunts for new dental ideas or methods to stop dental problems
• at least: dental school, journals, and education programs
• attends lectures on preventative care
• interacts with other dental professionals
• reads (some of) Dentistry Journal, J of ADA/Calif DA, J of D Education/Research, General/Pediatric Dentistry, Caries Research, Archives of Oral Biology, FEMS Microbio Reviews,  J of Clinical Microbio, Infectious Immunology, J of Clinical Pediatric Dentistry, oral health and preventative dentistry, Micro-organisms of human mouth, J of Clinical Periodontology, A J Epidemiology, J of Endodontics, Annals of Pharmacotherapy, 
• Cleanings make bacteria attach more easily, but also remove a significant amount of them. Unclear if they're beneficial, if you have a good home care routine. (if you don't take care of your teeth then of course they help...) 

old method of fillings - cut grooves into tooth to retain filling
new method - etch, fill pores w/ plastic resin ("sealant")
sealants useful for small cavities, pits, grooves - worry about bacteria though

Minitutorial on teeth and how they decay

Structure of tooth is similar to egg - shell corresponds to enamel - immerse in vinegar, shell turns to rubber (but does not vanish; just breaks really easily)
soft teeth look dark or yellowish, just need time/care to harden/lighten - don't use bleaching agents
note that fluorescent lights make teeth look yellow regardless

tooth parts (outside to inside):

• Plaque - mesh/biofilm of protein strands, many bacteria types, and other substances, fluids, and cells; can have a protective or harmful effect on teeth
• enamel - continuously changing mesh of watery film and mineral crystals (calcium hydroxyapatite - key elements calcium and phosphate)
• in presence of fluoride, crystals form faster, structure is calcium fluorapatite - larger, stronger, smoother, more symmetric, and shinier crystals
• acid dissolves both types, some is normal but too much is bad
• porous teeth are sensitive, fragile, and temperature-sensitive
• demineralization/remineralization - shrinkage/growth of crystals -acid demineralizes, saliva remineralizes
• usually clear, like glass
• dentin - softer than enamel, very porous, creamy white, tubes
• pulp - soft living tissue w/ blood supply - odontoblasts
• gum - seals roots off from rest of mouth, protects roots

Caries

• bad bacteria transferred by contact w/ infected saliva on food, utensils, hands, etc.
• There are ~700 species of bacteria, mostly competing for resources in the mouth. Their functions are still an active research area, but it's clear that some are worse than others in terms of cavities, and you want to get rid of those, e.g. Streptococcus mutans and some lactobacilli. Yeast is another possibility.
• bacteria attach to a hard, non-shedding tooth surface
• eating - bacteria process some of the sugar and produce acid
• acid eats away at the nearby portions of tooth, weakening it and eventually causing cavities
• bacteria cause gum disease too, attach near gum/tooth line instead of on tooth

Signs that you have a problem (from bad to worse):

• gingivities - mild inflammation of gum, 1/7 adults
• enamel on outside surface of back molar teeth chips away (where teeth bend and flex)
• back teeth are sensitive
• bleedings gums
• periodontis - severe inflammation of gums
• periodontal pockets form
• fillings fail and need replacement
• gums need extra cleaning
• gum recession, exposed roots showing cementoenamel junction
• root-canals and crowns
• extractions, implants, bridges, dentures

Ways to prevent:

(all of these happen naturally, but you can help the process by being conscious of it and using various products)

1. Control which bacteria you have - don't share saliva, remove infected clumps of bad species, eat clean food
2. Prevent bacteria from attaching to teeth - brushing, flossing (questionable), chew gum, protective sealants, fillings
3. Kill the bacteria - xylitol, antiseptic rinses, less mouth sugar/food, immune system
4. Protect teeth - fluoride, pH, minerals, saliva flow (gum, ...), protective rinses

 Methods

Fluoride

• strengthens teeth. benefits mostly when in direct contact w/ outside of tooth, for as long as possible
• good for teeth in moderation (toothpaste!)
• extreme amounts can cause fluorosis in anyone
• fluoride before age 3 can poison ameloblasts (teeth cells) and cause even more problems
• breast milk has low fluoride, infant formula might have high fluoride - bad
• types:
• sodium fluoride - well studied, pretty safe, more expensive than other types
• stannous fluoride - reduces gum inflammation, but brown/black staining of teeth
• silicon fluorides - not well studied (commonly found in fluoridated water)
• fluoride sources - foods, sodas, beer, infant formula, powdered iced tea, ...
• Fluoride rinse - last thing before bed, first thing in morning; spit at least twice to remove extra stuff
• recommendation: dilute ACT 0.05% fluoride, with no alcohol
• very little is needed, just enough to coat the tooth surfaces (a few drops)
• rinsing more often w/ fluoride gives better results
• Topical high-concentration rinse doesn't do much for healthy teeth.
• Fluoride gels/foams only effective when applied for >4 minutes on disease-laden teeth
• fluoride varnish - recent option for low-dose fluoride, numerous studies touting effectiveness
• Fluoridated water... but:
• tends to use less-studied (cheap) fluorides, which might have adverse health effects (e.g. heavy metal poisoning)
• can't control - it's better to filter your tap water and buy your own (sodium) fluoride

Behavioral Saliva /  PH Control

• Probably the most effective, after fluoride.
• Measure saliva pH (litmus, special probe), also amount (saliva buffer kit)
• To take mouth acidity reading: 
1.  Spit saliva into spoon
2.  Test w/ pH detector
•  do when you wake up (base pH, should be neutral or alkaline, close to 7, <6 is worrying), then 10-minute intervals over course of day to see how drinks/foods change the pH - typically return to normal takes ~30min, quicker is better
• Know pH of liquids you commonly drink (e.g. the water)
• Saliva contains minerals for rebuilding teeth (remineralization), lubricates teeth so they don't grind while eating; normal saliva contains all the needed minerals, specifically rinsing w/ minerals is generally unnecessary
• dry mouth is related to dry esophagus, leaving it open to bacteria or fungi which could give symptoms of acid reflux
• healthy saliva is neutral or alkaline; should return acidity to safe levels ~30 minutes after eating
• saliva flow increases at mealtimes and reduces during sleep, varies according to person and situation
• stress thickens saliva and make your mouth dryer - go to sauna/beach, practice meditation/relaxation, frequent exercise

Good foods:

• potatoes, asparagus, broccoli
• fresh veggies/fruits, veggie juices
• herbs
• vitamins/minerals, and waters with them
• whole grains
• bananas, almonds, fresh apples, pineapple
• milk, cheese, other dairy products
• tea, coffee
• chocolate, licorice, pure cranberry juice - intense sweeteners
• alkaline soups/broths/water

Non-food stuff:

• propolis (bee product)
• chewing gum
• plant fibers/leaves - even chewing sugarcane is good

Bad stuff:

• acidic food
• acidic drinks (worst to OK)
• frozen fruit juice
• lemon juice, lemonade
• citric, apple, and grape juices - even diluted they still cause problems
• soda, sports drinks, coffee, beer
• sugar/carbohydrates (if bacteria present)
• Halloween candy - best to eat it all at once (unless you're diabetic)
• corrosive, abrasive, or whitening oral care products 
• includes Listerine, don't leave it in your mouth
• bleaching - horrible - damages enamel - sensitive teeth, inflamed gums, gum recession, etc.
• sugarless products (diet soda, sugarless cookies)
• sorbitol causes gastric problems and feeds the bacteria too
• gastric acid
• grinding teeth stresses them and causes problems

Ellie's 3-Rinse Care Procedure

(2x / day, once before sleeping and once ~12 hours later)

1. Prerinse with pH-balanced/stabilized unflavored chlorine dioxide rinse (Closys/Retardex)
• salt water probably would work too
• baking soda,peroxide - sensitize gum, don't work
2. Brush teeth, in particular gum-tooth edge, all the way around the mouth
• Use toothbrush - head <1 inch in length, easily-grasped handle, soft/giving bristles w/ round ends, should be able to reach upper outside and lower inside easily
• Toothpaste - old-fashioned, boring, low-chemical, low-tech, no abrasives, few additives, no whitening, "gentle", sodium fluoride, ADA seal
• dicalcium phosphate dehydrate- abrasive 
• recommend Crest Regular Cavity Protection
• Brush bleeding gums, heals in a few days if bacteria are removed
• use warm water/prerinse + soft cloth instead of toothbrush if sensitive
3. Disinfect toothbrush (1x/day)
• Swish bristles in 0.5oz undiluted antiseptic/antibacterial rinse (Listerine) for 30 seconds
• Rinse off w/ tap water
• Alternatively: use UV box
4. Store toothbrush w/ head upright, in cup, allowing bristles to dry completely before using again
• ensure head doesn't touch other brushes to avoid contamination
5. Use antiseptic rinse (listerine), swishing around everywhere in the mouth
• should have ADA seal, good taste, no whitening/abrasives - can dilute if needed
• Spit out, don't rinse
6. After antiseptic, immediately use protective anticavity rinse, esp. before sleeping
• 0.05% sodium fluoride ACT
• goal is to rebuild teeth
• don't wash off afterwards, keep on as long as possible
• swishing toothpaste around your mouth w/ a small amount of water can be used instead of a rinse, but does require spitting it out again

The toothbrush breaks up plaque films and rinsing afterwards mechanically removes most bacteria. Flossing breaks up plaque as well, but it's not particularly effective (it's mostly good for removing food particles). However, the toothbrush is inadequate for periodontal pockets, only goes ~4mm deep. A Waterpik works but breaks far too easily; the antiseptic mouthwash works pretty well for gum pockets. Also see Periogen, not mentioned by Ellie but seems effective at periodontal restoration / prevention (it has a cult internet following, although it's overpriced). Similarly sodium hexametaphosphate inhibits calculus and loosens extrinsic stains, and in general there are lots of interesting rinse additives to explore.

Xylitol

wood sugar, available in specialty stores
Sciency mumbo-jumbo:

• antibacterial effects
• less buildup of plaque for some reason
• 5g had strong effects, even with a 3 month break
• 6.5g a day - after 5 wks, reduced; afer 6 months, bacteria gone. for 2 years, plaque reduced significantly - no buildup at all.
• past 10g/day, no generic effects, but some suggest for calcium absorption
• xylose + other 8 sugars precursors to some important proteins
• also reduces ear infections
• stimulates saliva flow like other foods 
• 15g naturally produced by body (though not in saliva)
• 100g/day eaten w/out obvious ill effects

Ellie's website (Zellie's) sells xylitol wipes, gum, mints, rinses, etc., obvious conflict of interest. She recommends 6-10g/day in 3-5 doses. Buying in bulk from her website, the cost per day ranges from 75 cents (gum) to 48 cents (mints) to 13 cents (granular xylitol). For comparison, the general recommendation is to use 1g of toothpaste and brush twice a day, so your typical $3 232g tube of Crest Regular Cavity Protection toothpaste is only 2.5 cents a day, and 20ml of $5/L Listerine mouthwash once a day is 10 cents a day.

Thoughts on Google I/O 2016 Keynote

So, I watched the Google I/O 2016 Keynote. As usual, my thoughts are different from other people, so it's worth writing them down.

• Music: those were some cool people in the beginning. But Google can't find their music, and they have no credits in the schedule. What gives?
• Intro movie: reasonable, I guess it was a spin on the play store. Dubstep's still not my thing.
• Knowledge Graph: still not useful enough to disambiguate "simon haskell" into "simon peyton jones" and "simon marlow". And considering the reasons for the removal of the 'phonebook' operator, I'm not sure it ever will.
• Machine learning: it's (mostly) open source, no real objections here
• Buying from movie theaters: Is this still a thing, in 2016? What's wrong with Netflix? I assume Netflix can give much better movie recommendations than Google (although it would be nice to have competition), and unlike Google there aren't any difficulties with availability.
• Ordering food: the ordering part is ok, but I'd rather have it show up as a persistent notification than as a text bubble
• Google Home: The majority of examples there should be automated; telling a speaker to turn on the lights every morning is tedious. The flight planning stuff and sensor control seems like it would work better with a touchscreen.
• Allo: the intelligent completion should be in the system-wide keyboard, rather than the messaging app. Too late now I guess.
• Duo: same here, improve the platform rather than the app
• Watch: sounds like watches are the new phones. but do they make calls?

An immediate interpretation of probability

Given that many interpretations of probability have been considered and rejected*, it is not clear that a simple interpretation of probability exists. For example, the rhetorical flourishes of the simple interjection “Fat chance!” are unlikely to be captured in a rational* discussion. Furthermore, even if such an interpretation did exist, it is not at all obvious that a paper should be written about it. For example, a study of monkeys, who share 93% of DNA with humans*, shows that they do not use writing in the wild. Monkeys are nonetheless able to learn simple mathematics* and English*. We thus defer discussion of the subject by treating the paper as a preliminary mere-exposure experiment*; it does not need to be approved in advance due to essays falling under normal educational practices*.
Our interpretation may be termed immediacy. Consider the statements “Alex is wearing a red sweater” and “Alex is wearing a blue sweater”, and assume that the former was observed yesterday but the latter is present today. Qualitatively, these perceptions are different. We can interact with the blue sweater, for example by splashing paint on it; we term this “near”. In contrast, the red sweater exists only in our mind; we may have recollected incorrectly*, for example, if Alice was wearing a red sweater but swapped desks with Alex; we term this “far”. The far reality is mentally constructed, with no direct perceptual connection.
Far reality is fragile. Consider a child with no experience of elevators, taking their first ride alone. The door closes on their parents, a number changes, the elevator beeps, and when the door opens again a new space is presented, with complete strangers and no parents in sight. Confusion results, only resolved by introducing a notion of “floor” and its corresponding sensations and notifications of vertical movement.
A reasonable reaction is to ask is how to avoid the possibility of being confused. Unfortunately, we run into the problem of incompleteness*, and in particular the problem of other humans*. Although a problem may not necessarily have a solution*, it may have an approximation; furthermore, we can categorize the techniques used to approximate the solutions, in this paper termed “mental constructions".
What are mental constructions? Again, an example: “The visual system, although highly complex*, in its most basic elements appears to function as a recording and processing device*.” The previous sentence is simply a reflection of the dominance of the computational paradigm*. A better model than simple computation is the act of writing itself, wherein letters are sequentially produced on a page by some complex process with memory*. We of course lose aspects of humanity when we attempt to describe it in writing, but it is futile to expect to solve these problems via more writing*, so we stop there. Thus, for our purposes, mental constructions are recurrent processes that result in the production of writing. Finally, then, we arrive at our interpretation of probability; given several possible processes with which to produce writing, select one (for this paper, a randomized variant of the autofocus system*).
One particular strength of our interpretation is its similarity to the etymology of probability*. The word probability originates from the Proto-Indo-European root *pro-bʰwo-, meaning “‎to in front”. This came to be associated with the Latin probus, meaning good, noble, and virtuous. After morality became a common good*, there were then techniques of probo to test and certify what was good. Hypothetically this then became the Latin probābilis, meaning provable, credible, and finally probability as a measure of provability. In our case, provability is determined by a measure of verbosity; in particular, we measure proof as an estimate of the amount of processing done, via an analysis of the amount of references and obscure concepts used.
Another strength is its self-referential nature, more precisely homiconicity*; by writing a paper interpreting probability using a probabilistic paper-writing process, we achieve a similar representation of both paper and probability. Our interpretation thus covers a vast conceptual space in a small amount of time by utilizing foundational tools repeatedly, particularly the Axiom of Choice*. Although this might appear to be a weakness, in that the two are mutually recursive and thus could lead to an infinite regress, there are well-established base cases of an empty paper and not writing a paper. Furthermore, the homoiconic property ensures that the presented concepts can be reproduced by reproducing the paper.
A final strength of our interpretation is its synthesis of concepts present in frequentist and Bayesian probability. By its emphasis on writing, we mimic the emphasis on enumeration of possibilities found in frequentism. However, whereas a frequentist approach might focus on the space of possibilities, e.g. H and T in a coin flip, we fix the choice of possibility space (a sequence of English characters) and instead focus on the choice of process. Furthermore, we leave the general method of choice purposely ambiguous, thus implicitly introducing subjectivist notions of probability. But unlike Bayesian probability we successfully avoid the need to enumerate all possible choices of process, by introducing a stopping procedure (detecting the presence of self-reference). Our interpretation of probability is thus strictly constructionist* and does not introduce problems of computability or practicality.
Our interpretation does have a flaw, though, in that it does not guarantee optimality in any sense. For example, it does not preclude the possibility of accepting a Dutch book. Although it heavily emphasizes writing, references, and consideration of the means of production*, it addresses the possibility of an unconsidered approach only reactively. Furthermore, it does not necessarily produce agreement among different individuals*; they may make different choices in process. We submit three responses: first, that optimality is a theoretical concern* of no particular relevance to applied mathematics*; second, that our approach is optimal in terms of a suitably defined global measure of cognitive costs*; and third, that one can always postulate an independent third party that would use the process of considering and synthesizing all other processes*, but such a third party does not necessarily exist in practice.
Although any experiment is subject to uncertainty, we have attempted to minimize it through the use of a controlled environment and hypothetical situations. The most pressing concern is that the experiment could fail to produce any measurable effect. Particularly, its focus on references and concepts makes it conceptually difficult to understand, and thus it may be rejected altogether. Furthermore, the use of randomized concepts may make transitions in the paper appear stilted or disjointed. Time constraints forced the summarization, omission, and consequent misunderstanding of many concepts that require an interpreting paper in their own right. Nonetheless we look forward to seeing the results.

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