The human microbiome is a very interesting aspect of our health and biology.
The 99% figure they quote is mainly silly. It might be technically accurate, but it is much more misleading than accurate (if it is accurate). We have more non-human cells than human but those cells are much smaller and we are overwhelmingly made up of human cells by weight (95+%).
The complexity of healthy bodies is far from understood. It is interesting to watch our understanding of the balancing act going on inside of us. Many foreign “invaders” are critical to our health.
This webcast, from the wonderful SciShow, explores how we discovered fluoride helps prevent tooth decay and how we then used that knowledge and finally discovered why it worked.
I love stories of how we learn for observing what is happening. We don’t always need to innovate by thinking up creative new ideas. If we are observant we can pick up anomalies and then examine the situation to find possible explanations and then experiment to see if those explanations prove true.
After investigation the natural fluoridation of the water in Colorado Springs, Colorado, USA seemed like it might be an explanation (though they didn’t understand the chemistry that would cause that result). They also explored the sense that the discolored teeth were resistant to decay.
Even without knowing why it is possible to test if the conditions are the cause. Scientists discovered by reducing the level of fluoridation in the water the ugly brown stains could be eliminated (these stains took a long time to develop and didn’t develop in adults). Eventually scientists ran an experiment in Grand Rapids, Michigan and found fluoridation of the water achieved amazing results for dental health. The practice of fluoridation was then adopted widely and resulted in greatly improved dental health.
In 1901, Frederick McKay, a recent dental school graduate, opened a dental practice in Colorado Springs, Colorado. He was interested in what he saw and sought out other dentists to explore the situation with him but had little success. In 1909, he found some success when renowned dental researcher Dr. G.V. Black collaborate with him.
Dr. H. Trendley Dean, head of the Dental Hygiene Unit at the National Institute of Health built on their work when he began investigating the epidemiology of fluorosis in 1931. It wasn’t until 1945 that the Grand Rapids test started. Science can take a long time to move forward.
Only later did scientists unravel why this worked. The fluoride reacts to create a stronger enamel than if the fluoride is not present. Which results in the enamal being less easily dissolved by bacteria.
Health tip: use a dental stimudent (dental picks) or floss your teeth to maintain healthy gums and prevent tooth decay. It makes a big difference.
Pure Home Water, Ghana manufactures and distributes AfriClay Filters in an effort to bring clean water to 1 million people. So far they have delivered filters to provide 100,000 people clean water.
The process is simple. Water is placed in a clay filter and gravity pulls the water through the pores left in the clay during firing.
Sediment and bacteria are filtered out in several ways:
Physical straining: the particles are too large to fit through the pores in the clay
Sedimentation or adsorption: particles come to rest on or stick to the clay
Inertia: friction in the pores keeps the particles from passing through
Bacteria are also killed by a coating of colloidal silver (a disinfectant), which we apply to all filters that pass our quality control tests. While sediment and bacteria are filtered out, the molecules of water are small enough to pass through the pores in the clay.
The filters are sold to those who will use them. The effort has shown a willingness to pay by villagers in remote Northern Ghana (those earning < US$1/day). I imagine (I am just guessing) the prices are subsidized; in the last decade more (most?) appropriate technology solutions will have those benefiting pay something for the benefits they receive.
My nephews are working on a similar effort in India, using bio sand filters, I plan to post more on that later. There is current a campaign to help fund the delivery of water filters to Indian villages.
One of the treats of living in a tropical climate is drinking coconut water. I love drinking the water from fresh coconuts. This video provides insight into the many uses of all parts of the coconut tree.
[coconut water] has fewer calories, less sodium, and more potassium than a sports drink. Ounce per ounce, most unflavored coconut water contains 5.45 calories, 1.3 grams sugar, 61 milligrams (mg) of potassium, and 5.45 mg of sodium compared to Gatorade, which has 6.25 calories, 1.75 grams of sugar, 3.75 mg of potassium, and 13.75 mg of sodium.
There are some health benefits to consuming coconut water. It’s an all-natural way to hydrate, reduce sodium, and add potassium to diets. Most Americans don’t get enough potassium in their diets because they don’t eat enough fruits, vegetables, or dairy, so coconut water can help fill in the nutritional gaps.
Beyond that, the scientific literature does not support the hype that it will help with a laundry list of diseases. “There is a lot of hype about coconut water, yet the research is just not there to support many of the claims and much more research is needed,” says Cheung.
I have tried bottled coconut water which was pitiful. I don’t know if that was just a bad type and good options exist or the fresh stuff is just much much better. But I’ll stick to fresh coconut water as long as I can.
I think the video’s message is overly simplistic and unrealistic (great innovations often seem unrealistic so I don’t mind people trying things I don’t think are likely to succeed in the ways they imagine). But I believe in the concepts of using our knowledge to use appropriate technology to make the standard of living better for everyone. Open access to scientific knowledge is important to such efforts and to the economic well being of modern society.
The video, above, provides an overview of an online course, Calculus: Single Variable, via coursera from the University of Pennsylvania. This course provides a brisk, entertaining treatment of differential and integral calculus, with an emphasis on conceptual understanding and applications to the engineering, physical, and social sciences.
Robert Ghrist is the Andrea Mitchell University Professor of Mathematics and Electrical & Systems Engineering at the University of Pennsylvania. Coursera offers many courses in all sorts of disciplines including: Introduction to Genetics and Evolution (Duke), Scientific Computing (University of Washington), Principles of Economics for Scientists (California Institute of Technology), Game Theory (Stanford University and The University of British Columbia), A Beginner’s Guide to Irrational Behavior (Dan Ariely, Duke University), The Modern World: Global History since 1760 (University of Virginia), Microeconomics for Managers (University of California, Irvine), Data Analysis (Johns Hopkins University), Fundamentals of Human Nutrition (University of Florida), Algorithms, Part I (Princeton University), The Ancient Greeks (Wesleyan University), Astrobiology and the Search for Extraterrestrial Life (University of Edinburgh) and Epigenetic Control of Gene Expression, (University of Melbourne).
All the classes are free. These courses, and many more, are extremely appealing. I signed up for 2. I would be interested in signing up for much more but I worry about having the time to commit to keeping up with the coursework. I hope the first two go well and I can sign up for more in the future.
Fun cat video and a reminder to thank your mother for all the times she saved you from your version of the slide. Have a happy friday. Maybe you should forward this video to your Mom with a note of thanks and make it a happy one for her too.
Graeme, a cat in Melbourne, Australia, walks to the train station with its owner in the morning and then goes off to play (and probably lots of sleep, it is a cat) and then returns in time to meet its owner at the train station after the work day.
The pampered cat cannot get enough of attention, with scores of regulars calling him by name as they stop for a chat and give him a pat on the head. Safety conscious, the sociable moggie is meticulous about using the subway to cross to the city-bound platform, rather than take a dangerous short cut across the tracks.
When the evening peak comes around, Graeme puts on an encore performance, arriving at the opposite platform in time to greet owner Nicole Weinrich as she returns home from work. “He always seems to know which train carriage I am on and will be sitting there behind the yellow line when the doors open, because he is all about safety,” Ms Weinrich said.
But sometimes Graeme can take his desire to be close to his fans a bit too far – he has been known to jump on the train and get off a station or two later. “He doesn’t do it often, but we do worry about that,” Ms Weinrich said.
She said Graeme, believed to be about 12, had roughed it on the street before being saved from the RSPCA’s “death row” six years ago, so his love of people is tempered by his survival instincts.
Very cool cooperation between robots. It seems more and more research is going on in cooperative robotics. It would seem this would let us have specialized robots for various tasks instead of having to have robots that can do everything (which is very complex and difficult). Plus cooperating robots are just cool. See the Swarmanoid project web site and the overarching Swarmbot site. I look forward to what these scientists and engineers can create for us.
Our modern world is influenced greatly by algorithms. As computing power allowed incredibly complex calculation we have taken advantage of that and used algorithms to find solutions to our desires. Great things are done but we also find ourselves getting into trouble occasionally as we develop these algorithm.