sagansense:
Learn to Read a Scientific Report
Illustration/Image: Mattias Adolfsson
Don’t trust us. Which is to say, the press isn’t always the most reliable transmitter of information about well-being. But thanks to changes in funding and new publishing models, you can now bypass us altogether and read the actual research papers yourself. The problem is, that’s harder than it sounds. Reading an original paper isn’t the same as understanding it. Science journalists try to help on that front, but as with any filter, important bits can get lost in translation. So you need to explore a few critical elements—of the study or the media coverage about it—to determine whether it contains life-changing advice or something best deposited behind the couch in the dentist’s office. And what are those elements? Glad you asked.
Causation vs. correlation
How do you know if a study’s results answer the question it set out to ask? Sometimes an outcome is just a coincidence—there’s a correlation but no causation. Meta-analyses pool the results of smaller studies and filter signal from that kind of noise.
True size of the effect
Watch out for weasely language—a “threefold increase” might only be a shift from 1 percent to 3 percent. One recent paper reported that women’s mortality risk rose 133 percent. That sounds scary, but the elevated mortality rate was still just 1.9 percent.
Statistical power
Look at two key factors, the n and the p. The n is the number of subjects used in the study. Multifaceted experiments typically have fewer subjects than simple surveys. Genetics studies need a big n. The p value lets you know whether the result is “statistically significant”—it’s the probability of something occurring by chance alone. You want to see a p of less than 0.05. (Results can be statistically significant and still only show correlation, or have confounding factors.)
Conflicts of interest
Most journals now note this as a matter of policy. Was the company making the drug or product associated with the laboratory that did the study? Are any of the authors trying to sell a product? For example, the authors of a study exploring the effectiveness of “brain training” techniques on cognitive enhancement worked for the company that developed (and sold) those techniques. They disclosed this, but that’s still a red flag.
Source.
(via eatgeekstudy)
5:55 am • 7 October 2012 • 180 notes
“
Researchers in Aalto University have developed a new concept for computing, using water droplets as bits of digital information. This was enabled by the discovery that upon collision with each other on a highly water-repellent surface, two water droplets rebound like billiard balls.
Using the tracks, the researchers demonstrated that water droplets could be turned into technology, “superhydrophobic droplet logic.” For example, a memory device was built where water droplets act as bits of digital information. Furthermore, devices for elementary Boolean logic operations were demonstrated. These simple devices are building blocks for computing.
Furthermore, when the water droplets are loaded with reactive chemical cargo, the onset of a chemical reaction could be controlled by droplet collisions. Combination of the collision-controlled chemical reactions with droplet logic operations potentially enables programmable chemical reactions where single droplets serve simultaneously as miniature reactors and bits for computing.
The researchers foresee that the present results enable technology based on superhydrophobic droplet logic. Possible applications include autonomous simple logic devices not requiring electricity, and programmable biochemical analysis devices.
”
— Towards computing with water droplets: Superhydrophobic droplet logic (via myserendipities)
(via shychemist)
6:39 pm • 12 September 2012 • 100 notes
holymoleculesbatman:
Researchers at Northwestern University, Chicago have set a new world record for synthesising two new materials with the largest surface areas recorded to date. ( NU-109 and NU-110)
http://www.sciencedaily.com/releases/2012/09/120907125148.htm
(via scinerds)
7:02 pm • 9 September 2012 • 107 notes
jtotheizzoe:
World’s Smallest Scale Can Measure the Mass of a Single Molecule
This new nanomolecular scale is less than one micron wide at its center. By detecting how vibrations in the central arm change when a single molecule hits it, one solitary group of atoms can be accurately weighed.
More on the technical aspects and fabrication at Surprising Science.
10:12 pm • 27 August 2012 • 472 notes
amazinganatomy:
endless-emotion:
nerdsinmypants:
Stages of Deterioration in the Human Body
The Moment Of Death:
1. The heart stops.
2. The skin gets tight and ashen in color.
3. All the muscles relax.
4. The bladder and bowels empty.
5. The body temperature begins to drop 1 1/2 degrees Fahrenheit per hour.
After 30 minutes:
6. The skin gets purple and waxy.
7. The lips, fingernails, and toenails fade to a pale color.
8. Blood pools at the bottom of the body.
9. The hands and feet turn blue.
10. The eyes sink into the skull.
After 4 hours:
11. Rigor mortis has set in.
12. The purpling of the skin and the pooling of the blood continue.
13. Rigor continues to tighten muscles for another 24 hours or so.
After 12 hours:
14. The body is in full rigor mortis.
After 24 hours:
15. The body is now the temperature of the surrounding environment.
16. In males, the semen dies.
17. The head and neck are now a greenish-blue color.
18. The greenish-blue color spreads to the rest of the body.
19. There is a pervasive smell of rotting meat.
After 3 days:
20. The gas in the body tissues forms large blisters on the skin.
21. The whole body begins to bloat and swell grotesquely.
22. Fluids leak from the mouth, nose, vagina, and rectum.
After 3 weeks:
23. The skin, hair, and nails are so loose they can easily be pulled off the corpse.
24. The skin bursts open on many places on the body.
25. Decomposition will continue until the body is nothing but skeletal remains, a process that can take a month or so in hot climates, and two months or more in cold climates.
Wait wait wait
It takes a whole 24 hours for the semen to die?!
The wanker in me had to change the typo, but this is great!
(via unbearablevastness)
1:41 am • 13 August 2012 • 156,054 notes
jtotheizzoe:
If you’re an engineer, you usually try to design things that don’t collapse. But when it comes to some structures (like car crumple zones), designing instability can be very important. They are studying math, folding, origami and complex geometry. Read above about the engineers who are trying to design the artfully unstable.
Very cool stuff!
(via Nature News)
8:33 pm • 12 August 2012 • 264 notes
The Neuroscience of Prayer
jtotheizzoe:
Disconnect, for a moment, from the argument of whether prayer is real. That’s for another time and another place. The fact remains that it is an ancient, powerful, and widely practiced behavior. What is it about the human brain that encourages so many to appeal to a higher power? And what is happening inside the brain when people pray?
When we look at prayer through the lens of neuroscience, we can make an interesting observation: Talking to God is not really different from talking to one’s friends and neighbors.
The brain’s evolution was a highly social process and involved complex problem solving. Yet, invisible entities are not a force of natural selection. Check out this fMRI study of religious folks, and you’ll see that religious people’s brains view prayer as communication with an actual physical entity.
Believer or not, it’s good conversation fodder for your next cocktail party. For sure, it appears that religion is far more than illusion for the religious.
8:33 pm • 12 August 2012 • 572 notes
