11/4/13: NEW! WRIT
Two stories in the llast week from the New York Times bring to our attention transcranial direct current stimulation (tDCS) as a procedure to enhance mental or motor skills--A quick trip to the "focused," "in the zone" state that is at the peak of the Yerkes-Dodson curve! The relevant websites are
http://www.nytimes.com/2013/10/29/science/jump-starter-kits-for-the-mind.html

http://www.nytimes.com/2013/11/03/magazine/jumper-cables-for-the-mind.html?ref=magazine&_r=0

As I said when I recalled my own 9v. battery + potentiometer experiment as a UG at Berkeley, I didn't notice much in the way of improved "creativity" or "less need for sleep." Perhaps my ground electrode was just in the wrong place.

Read over the two articles linked above and comment in your essay on whether you think the claims about tDCS are legitimate...believable. What about tDCS in animal studies? How are electrodes attached to the scalp? How can a 9v. battery deliver 1mA of DC current?

Keep in mind your fellow student Ignacio, from Madrid, whose slides I borrowed for my "electrodes" lecture, as a resource.

WRIT 1
From a certain point of view, kidney hemodialysis hasn't changed much since it was invented in the 1950's. The cellophane-like filter that allows urea and other undesirable chemicals to be removed from blood still has a difficult time with some molecules, like phosphate. To supplement hemodialysis itself, patients are frequently asked to take binders with meals to help reduce phosphate levels. See the links below for a couple reviews of phosphate issues in hemodialysis:
http://ndt.oxfordjournals.org/content/17/6/1037.long
http://www.medscape.org/viewarticle/583906_5

Write an essay of more than 300 and less than 800 words speculating on what could be another way to deal with phosphate buildup in patients with partial or total kidney failure. Your speculations need not be technically correct or complete...here we are wanting to look at your thought processes put into prose to build a coherent argument about some possible new way--however fanciful or expensive--to reduce phosphate levels.

WRIT 2
Blood pressure of a human is normally taken by a nurse who inflates a pressure cuff on the patient's upper arm until no pulse can be detected with a stethoscope on the lower arm. She the nurse then opens a valve to slowly lower the pressure and listen for return of pulse. From observing a pressure meter when the pulse returns she concludes what the patient's systolic and diastolic pressures are, in mm Hg. A typical reading is 120/80. OK, so it's a cumbersome process...

Write an essay about how you think a blood pressure cuff could be calibrated. We want the calibration to as realistic as possible with regard to how the cuff is used. Note you will be worried about how the pressure is measured as a function of blood flowing (or not) as detected by a sound-measuring device like a stethoscope.

As another example of a biomedical device needing calibration, consider the "forensic breathalyzer" which must be calibrated to read out correctly the percentage of alcohol in the bloodstream. There carefully measured sources of 1% to 30% EtOH in vapor must be "blown" into the breathalyzer and repeated tries must result in the same correct answer each time. Defense attorneys for drunk drivers often question the accuracy of the breathalyzer used to charge someone with a DUI offense.

Again, speculate on what might be a calibration setup, and go into as much detail as you care to, regarding the calibration of a blood pressure cuff.

other topic choices:

WRIT 3
Here is a link to a recent NYT front page story about the cost of saline infusions in a hospital setting. The reporter tries to be matter-of-fact in her detailing of the seemingly high cost of saline bags for infusing, compared to the actual cost of 0.9% NaCl sterile salty water.

Write an essay on your reaction to the facts of the article as presented. Consider issues of secrecy and confidentiality.

Can you think of any technical or economic "fix" for this particular issue? Should patients be allowed to buy low-cost saline bags and bring such bags to the hospital with them? Should the government supply saline bags to hospitals "free of charge" and not allow any markup on bills to insurance companies?

Will Obamacare bring down the cost of saline bags?

WRIT 4
MOHS dermatological procedure and need for better pathology reporting. In a MOHS a dermatologist tries to remove a skin cancer tumor--but no more--from a patient. The surgeon at first excises what she thinks is the minimum amount of tissue that includes all of the tumor. Standing by is a pathologist who freezes and sections the tissue, accounting for its orientation in the skin of the patient. The pathologist looks at the margin of the excision for signs (perhaps by staining) that there are no cancer cells=> all of the tumor has been removed. If the pathologist sees irregular cells at the margin, the surgeon goes back to the patient and cuts out another ring of tissue to be examined by the pathologist. When the pathologist finally reports that no more cancerous cells (squamous or basal) can be seen at the margin, the surgery is finished (save for calling in a plastic surgeon to do his best restoring normal appearance to the area of skin operated on.

The problem is that the pathology procedure takes so long: an hour or so to freeze, section on a microtome, and move onto slides, and perhaps stain... then look through the microscope for tell-tale signs. Your essay: speculate on how the inspection of the surgical margin can be sped up. Think of a possible new way to to tell if the skin tissue removed contains all of the cancerous cells.

WRIT 5
Apocryphal story: The Smart endoscope: In colonoscopy an endoscope is guided up the colon--the descending colon, the transverse colon and the ascending colon. The endoscope has a fiber optic light and camera to allow the gastroenterologist to look for signs of colon cancer. Fine. The problem: The "dumb" endoscopes commonly employed have a hard time making the 90 deg turn from descending to transverse colon. Pain ensues. Anesthesia is called for.

Along come two mechanical engineers who had made a robotic snake. They realize that the "smart snake" could turn the 90 deg corner of the colon by having its "snake segments" sense that joints needs to rotate and change direction so the segments march around the corner painlessly.

A few years (and 50 employees) of work result in exactly what was hoped for. The "smart snake" received preliminary approval from the FDA because of a small clinical trial. The Smart Snake marketing team then went out to sell their device to gastroenterologists who run the colonoscopy outpatient centers. One benefit of the smart snake: less anesthesia needed--just mild sedation. One marketing agent got excited and went around telling the GI docs, "It's so easy even a nurse can use it!" One GI finally said, "Well then what am I supposed to do?" and was told that the device would mean more colonoscopies per day, or some such thing.

Result: At a gastroenterology conference word went around about the "nurse could do it" remark and no one ordered the smart snake for their practice. After more futile attempts to sell the snake, the company laid off engineers, then within a year went out of business.

Apropos of the story above google "Robots vs Anesthesiologists" and read about J&J's automated anesthesia machine for colonoscopy procedures, and the strong protests being lodged by the American Society of Anesthesiologists. (handout from Sept 26 WSJ will be distributed).
more here

Your challenge: write about what you think of the story presented here, what the company could have done different from the start... Say how you think new technology should be "sold" to practicing physicians.