Fourier Analysis is a mathematical tool which can do a number of things: separate out signals from noise; help identify patterns or trends in data; filter out all unwanted data and focus on a single signal; use approximations to make generalizations; make approximations of real world signals (think electronic music); combine harmonics to get a stronger signal. That's what I'll be trying to do here!! Won't you join me with your comments?

Tuesday, October 13, 2009

It's Not Easy Being Clean...

Having been raised on a farm in Texas, I grew up thinking that dirt was a good thing, as the quality of the soil directly affected the crops and therefore the family income! I played with mud instead of Playdough. Sweat was natural and odors were common. And dust was a fact of life and we just never got too bothered about it. Only as I got "citified" did things change somewhat, to the point where I was advised by my children's doctor to NOT bathe them more than 2-3 times a week or less as they both had very sensitive skins and were better off with their natural protection. However, as my husband will testify, I still don't get too bothered by dust...*sigh* I will never make a good German "hausfrau".

But while I am not the cleanest of housekeepers, I do know a lot about cleanliness, indeed some things I wish I didn't know... (keep reading at your own peril!!)

  • The human body is home to over 1000 different kinds of bacteria. In fact, there are more germs on your body than the population of the United States. We actually have more bacteria living on us than there are cells in our bodies!
  • Housedust is composed of fibers from carpets and textiles, mold and plant spores, food and plant fibers, dander and skin flakes from people and animals, insect and spider parts, pollen, small bits of paper, household insulation and foam backing from carpets, and other minute particles. Dust mites feed off of dead skin cells and of course their excrement also makes up a component of dust. It is this substance that is one of the most common sources of allergens and what people refer to when they say they are allergic to "dust".
  • Sorry to disillusion some of you, but there is no "5-second rule" when it comes to dropping food on the ground. Bacteria need no time at all to contaminate something, all they need is contact!
  • And yes, in theory you can catch some diseases by sitting on a public toilet seat. Such locations have been found to have both common and unfamiliar strains of bacteria such as E.coli, hepatitis A, streptococcus, staphylococcus, and shigella, as well as strains of common cold and flu viruses and sexually transmitted organisms. But if your immune system is healthy and you always wash your hands afterwards, then you are at very little risk. Most disease-causing organisms cannot live long on the surface of a toilet seat and the chances of contamination to your buttocks or thighs could only occur if you have an open wound when sitting on one, and even then it is very unlikely.
  • Killing all bacteria, however, is actually less healthy as most of the over 1000 species of bacteria that make their home on the human body are beneficial to us in a mutual relationship -- we keep them alive and they keep us healthy. Despite some advertisements to the contrary, the more bacteria free you are, the more vulnerable you are to disease.
  • Another reason not to invest in anti-bacteria soaps, is that they have been found to be no more effective at preventing infection than regular soaps. In fact, those products containing triclosan actually can alter hormone levels and reduce libido.
  • Recent studies of children have shown that those who had an "overly hygienic environment" during their early years (up to age 10) were more at risk to develop asthma and eczema as well as more prone to allergies as they got older. One of the theories behind these results is that the young immature immune systems need to be challenged on a broad scale in order to build up a flexible pathogen resistance.
  • The origin of soap was actually a waste product of wood ash and animal fat that was polluting the Tiber river coming down from Mount Sapo. Women found it aided in getting their clothes clean when they did the laundry on the river's banks.
  • And early anti-bacterial substance that was used by Egyptians as well as Aztecs was urine. The key chemical in it, urea, was actually effective in treating cuts and burns as it kills bacteria and fungi which are the major sources of infection.
  • The founder of the Methodist church in the 1700's, John Wesley, is the author of the famous quote "Cleanliness is next to Godliness." but he was actually referring to clothes, not personal hygiene.
  • Society was not always so picky about personal hygiene. In Roman times, the sweat, dirt and oil that a famous athlete or gladiator scraped off himself was sold to their fans in small vials. Roman women reportedly used it as a face cream.
  • The medieval saint, St. Lutgard's saliva was believed to heal the sick, as were the crumbs chewed by another saint, St. Colette. A man sent from England to the Netherlands for St. Lidwina's washing water, to apply to his afflicted leg. The water from St. Eustadiola's face- and hand-washing was reported to have cured blindness and other illnesses.
  • Austrian men would place a handkerchief under their armpits while dancing and when it had soaked up their sweat and scent, they would use it to wipe the face of the woman they were courting, believing she would be aroused by the odor and fall in love.
  • King Henry IV was one of the first royal monarch's to try and move his society towards more cleanliness as he insisted that his knights bathe at least once in their lives during the ritual of knighthood. The rest of society, however, remained firm in their beliefs that bathing was unhealthy. Queen Elizabeth I was regarded as a model of cleanliness in her time. She declared that she bathed once every 3 months, whether she needed it or not. Actually the custom of daily bathing is something that has become common only after the 1950's.
  • Monks of an offshoot of the Hindu religion in India, the Jain Dharma, are forbidden to bathe any part of their bodies besides their hands and feet. Their belief is the act of bathing might jeopardize the lives of millions of microorganisms.
  • If you eat a lot at fast food restaurants, you might want to skip this factoid! Recent investigations have shown that the ice machines in fast food restaurants have more bacteria and higher concentrations of harmful bacteria than the water in your toilet bowl (assuming you keep your toilet reasonably clean). Fresh toilet bowl water is not necessarily contaminated and pets drinking from the toilet bowl may know more than their owners about clean water!
  • Most infections are transmitted by people handling something with germs on it and then rubbing their eyes or putting their fingers in their mouths or touching food that then goes in their mouths. Actually the mouth has a lot of natural defenses against germ attack. "Mother's spit" is not as unsanitary as it might seem as saliva is a natural anti-baterial fluid!But our eyes have very little natural protection.
  • One of the most contaminated objects in hospitals are TV remote controls! They are worse than toilet handles and are believed to be a major contributor to the estimated 90,000 annual deaths from infections acquired in hospitals.
  • Sufficiently grossed out now? Thought so! I will therefore refrain from the various facts about dental hygiene and lavatory practices except to refer back to back to last week's Tidbits: NASA spent over $23 million dollars designing the toilet for the Space Shuttle which uses suction technology of 860 liters per minute so that it will work in zero gravity (part of the reason why positioning oneself on the seat is so important). Still, I think that is an awful lot of money for a toilet that sucks...

Wednesday, October 7, 2009

Yes, NASA is bombing the Moon, no, they are not after Osama Ben Laden...

This week, Friday, 9 October, 2009, NASA will send a missile into the Moon at twice the speed of a bullet. As part of the LCROSS (Lunar CRater Observing and Sensing Satellite) mission, scientists have selected a target close to the Moon's south pole. At this time the plan is to target crater Cabeus A, but the exact location is still being determined based on data and information that scientists and mission controllers are gathering as the satellite approaches the moon.

This mission was launched back in June and is part of an ongoing program that NASA has to try and find any water ice that might be trapped in crater shadows. The Moon is primarily an airless, dusty/rocky desert and about the only place where water could be trapped is in areas that do not receive any sunlight. Water is a critical component in making any manned moonbase project a success. Transporting water and other goods from Earth to the moon's surface is expensive. Finding natural resources, such as water ice, on the moon could help expedite lunar exploration.

The missile impact is expected to be so powerful that a huge plume of debris will be ejected. Just as the impact of the Shoemaker-Levy comet fragments into Jupiter revealed a lot of information on the compostion of Jupiter's atmosphere, scientists hope hope that water ice or water vapour will be ejected in the cloud that is thrown up from the impact. As the ejecta rises above the target crater’s rim and is exposed to sunlight, any water-ice, hydrocarbons or organics will vaporize and break down into their basic components.

Following the missile, another part of the spacecraft will be taking pictures and analyzing the ejecta for evidence of water. The instruments include two near-infrared spectrometers, a visible light spectrometer, two mid-infrared cameras, two near-infrared cameras, a visible camera and a visible radiometer. The spectrometers analyze the breakdown of the ejecta materials into their basic components. The infrared cameras will help determine the amount and distribution of the water vapor and the visible camera will tract the location of the impact and the debris plume.

All this will take place in just four minutes and then this craft itself will crash into the Moon itself, producing an even more spectacular explosion. What is interesting about this is that this second explosion should be visible in the 10-12 inch and larger telescopes of amateur astronomers! The projected impact at the lunar South Pole is currently: Oct 9, 2009 at 4:30 a.m. Pacific Daylight Savings Time, which is 9 hours behind Central European Daylight Savings Time of 1:30 PM. So we in Europe won't get much chance to have a peak, but if you get up early enough in the US, depending on where you are, you might be able to see it.

Otherwise, NASA will be providing a live broadcast of this event starting at 3:15 AM PDT which can be seen online: www.nasa.gov/ntv. Additional information on the LCROSS mission can be found here: www.nasa.gov/mission_pages/LCROSS/main/index.html.

No, this is not an attack on an alien base on the moon. Nor is it a misguided attempt of Obama's administration to root out a new Al-Qaeda hiding place. It is not vandalism or scientist's frustration with the lack of funding for space science. It is a valid and useful experiment and a good way to find information without the expense and hazards of a moon landing to bring back samples to Earth.

And while there is some controversy about such an experiment, it should be noted that this is not the first impact by spacecraft on the moon. This past June, the Japan space agency, JAXA, sent its robotic probe, the Kaguya spacecraft, on a controlled impact into the moon after the completion of its mission and the exhaustion of its fuel supply. As this happened on the dark side of the moon, there was not a reach chance to view the ejecta from the impact, but there was a brilliant explosion that was caused purely by the energy of the impact and it was viewed by a number of astronomers with some spectacular images captured by the Anglo-Australian Telescope in New South Wales.

And in 2006, ESA's SMART-1 concluded its scientific observations of the Moon through a small impact on the lunar surface. This kind of conclusion to a lunar mission has actually been common through the years and scientists have watched them closely, gleaning what additional data they could from the debris of such impacts. Observatories around the world have conducted fast imaging of impacts and of the associated ejected material, and spectroscopic analysis, to try and find hints about the mineralogy of the impact areas.

However, this "accepted practice" has not caused the controversy in the past that this week's mission has raised, with some folks exaggerating the impact crater size as being up to 5 miles, others stating that it "...is contrary to space law prohibiting environmental modification of celestial bodies." And even some folks worried about it triggering potential "...conflict with known extraterrestrial civilizations on the moon as reported on the moon in witnessed statements by U.S. astronauts." *sigh*

In truth, there is no actual explosives on board, and the impact vehicle is just the upper stage of the rocket that launched the mission in the first place. It is estimated that it will excavate a crater approximately 20 meters wide and almost 3 meters deep and more than 250 metric tons of lunar dust will be lofted above the surface of the moon. It is not expected to be a spectacular explosion. Though at this time it is unknown about the kind of response we can expect to get from the lunar aliens... (this last sentence is just a joke!!!)

Tuesday, October 6, 2009

Why I Should Be Glad I'm NOT an Astronaut...

OK, I admit it, I am an ├╝ber-geek. However, for most of my adult life I have been in a position to explain very technical things to non-technical persons (laypeople). Thru the years I have acquired a broad base of factual knowledge that I constantly add to. This comes in very handy at social occasions when stimulating "small talk" is appropriate, and also makes me very good at playing Trivial Pursuit.

As I kind of use this blog as a conversation with yawl, my "Dear Readers...", I decided to start a little project I am calling "Tuesday Tidbits" in which I will be posting a collection of what I consider are interesting facts on various subjects. If you also want to play along, drop me a line and I will mention it here. And if I can get inspired, I might even come up with a cool button to go along with this.

Today, I give you some of the facts that I use to help me overcome that twinge of regret at "the road not taken", namely "Why I should be glad I'm NOT an astronaut..."

  • It stinks. Literally. And we are talking nausea-inducing smells sometimes. While the current ISS is not nearly as bad as the old Russian MIR space station, and after an hour or two the sensation wears off, those first few hours can be very hard. Where do the smells come from? Well along with the outgassing from plastics and synthetic materials, you of course have a mixture of various body odors from astronauts who have not really had a good shower during their entire tour of duty and who have only one set of clothes. And of course various lingering food odors, and the residue odors after the food has been "processed" by the bodies of the various ISS personnel. (See below where I talk about the toilet). Oh yes, there are fans and scrubbers and additional oxygen is added, but just ask any sailor who has served on a submarine...these devices are far from perfect! Yes, the human nose is adaptable and very few visitors to the ISS will really complain about the small inconvenience this poses, but the fact remains...it stinks!
  • At some point in time, everyone who travels to space gets space-sickness. The space docs know this is caused by the inner ears being confused by the lack of gravity and the visual cues also being mixed up. Sometimes it is not only nausea, but also headaches and loss of body and limb sense. Can you imagine not knowing where your arm is? Seriously, it doesn't sound like fun. I mean I've been on dates in college where the guy claimed to not know where his hand was, but I think this is a bit different...
  • Weightlessness may make the scales go to zero, but it makes you look fat. We are talking serious bloating here. Fluids shift upwards and towards your extremities, sinuses congest, faces get puffy, we are talking some of the worst symptoms of PMS here. Not attractive!
  • In addition, weightlessness causes bones to lose calcium and increases the chances of forming kidney stones. Here I am already fighting osteoporosis on the ground, and outerspace would do even more damage in a very short period of time. Not only that, it causes muscles to atrophy and the heart to shrink. Can you imagine how much extra exercise those astronauts have to do to combat those problems. (I hate exercise by the way, so this really is a negative for me!!) The fact that one gets taller (up to 2 inches or 5 cm!) is some compensation, but it only lasts while you are in space.
  • Sleeping arrangements are kind of odd. Most astronauts attach their sleeping bags to the wall of their little cubicle. Except there are only 2 cubicles and usually a minimum of 3 crew members. The odd astronaut(s) out are allowed to attach their sleeping bags anywhere inside the space station. Astronaut Susan Helms slept in the huge Destiny Laboratory Module by herself while she was living aboard the International Space Station. Some of the shorter astronauts, who of course do not suffer from claustrophobia (something astronauts are screened against), have even made a nice little nest for themselves in the larger storage drawers.
  • While the astronauts are scheduled for 8-hours sleep periods, their circadian rhythms are often thrown off by the 16 sunrises per day. Shuttles command crews have even more difficulty when they try and sleep in the cockpit with bright sunlight and warmth entering the cockpit every 90 minutes, though sleeping masks do help. The good news is that most snorers are reported to stop snoring while they are sleeping in space.
  • It is a good thing that most astronauts don't snore in space, as all noises are heard while living in such cramped quarters. At least those that are above the ambient noise level which has slowly been rising as more and more experiments and equipment is installed on the ISS, although some improvements have been made. All ISS astronauts used to have to wear earplugs all day, but now are only required to wear them 2-4 hours per day. That did not stop two ISS crewmen from suffering permanent hearing loss during their 6-month stay that ended in April.2006, as reported by Russian authorities, though NASA refuses to comment on the health of individual astronauts. The living quarters of the ISS is the noisiest module, with current goals in the sleeping cubicles at a maximum of 50 decibels (dB) and in the work area of 60 dB. Decibels are measured on a logarithmic scale, meaning 60 dB is 10 times louder than 50dB. For comparison, most window air conditioning units or washing machines or your electric toothbrush operate at noise levels of around 50 dB, while phones, alarm clocks and vacuum cleaners operate at around 60dB.
  • While there are some funny videos of ISS crew members eating in space, in truth it is more of a chore than a pleasure. While swallowing in zero gravity is not really a problem, getting some flavor into what astronauts swallow has been. Salt and pepper spices in liquid form have been included. All food is canned dehydrqted or otherwise packaged so it doesn't need to be refrigerated. In fact, there isn't anything served cold on the ISS, it is either heated or served at room temperature, nor is their any fresh fruits, vegetables, etc. Most things have some sort of sauce on them so that they will stick to a spoon, a fork is not needed. And of course the antics of squeezing things from plastic pouches and maneuvering food from containers to mouths requires a lot of concentration. It is not a good idea to have bits of dinner floating about in the space station...
  • Which brings us to the next topic...going to the bathroom in space. NASA did make an attempt a building some sort of waste elimination facility into its space suits, which meant a fitted condom attached to a waste packet for men and a molded gynecological insert for women...but it gave up and passed out diapers to all. Both the shuttle commode and the ISS have bathrooms, but using the toilet requires that crew members precisely align themselves in the dead center of the seat. A mock-up of the toilets is used during astronaut training, complete with a built-in camera and personal technician to aid in viewing the video to assist in training all the crew members on how to position themselves. One would definitely have to lose one's modesty in order to become an astronaut... Oh, and I guess I should also mention that just recently, while the ISS was boasting of its largest complement of crew members, 13 in total, one of the two toilets failed. It came close to being a real crisis before they got it repaired.
  • While zero gravity may at times be fun, returning astronauts report extreme difficulty in moving and controlling their arms and legs after touchdown. But the biggest adjustment comes for crew members who have spent longer terms in outerspace who say they have to remember that when they let go of objects, they fall!
  • And of course there are the dangers no one wants to talk about, like radiation. Radiation inside the ISS, as on the former Russian space station Mir and the Space Shuttle, is actually released by the materials that make up the vehicles and is caused by the cosmic rays colliding with the hulls, releasing secondary particles. While the exposure of a crew member spending around 3 months time in this environment amounts to the equivalent risk of someone on Earth getting radiation from natural sources in one year, it is therefore deemed an " acceptable risk". The problem is, that the effects of this kind of radiation on the body are not well understood. And there is not clear way to translate the estimated radiation exposure into the increased risk of cancer. One study puts an estimate of a 20% higher risk of dying of some kind of cancer, and a number of crew members who have spent 6 months or more in this kind of environment have already shown chromosomal abnormalities. It is therefore impossible for authorities or even the crew members themselves to make an informed decision about the potential damage their job may be doing to their health. Sounds pretty risky to me...
  • And then the biggie, the vacuum of space. Now science fiction movies like to show people exploding. Actually, you wouldn't explode, unless you were holding your breath, in which case the sudden depressurization would cause your lungs to rupture. But lack of oxygen in your blood would be what kills you, and that would take about 2 minutes, and you would probably be conscious the whole time. Of course it wouldn't be pleasant, as water on your tongue and eyeballs would boil away (not from heat, but from the lack of pressure). Scientists know this from and experiment where a space suit failed and the tester was exposed to near vacuum for 15 seconds. Thus far there have not been any ruptures to the ISS and it has had a number of hits from micro-meteors which have damaged several systems, but nothing critical...thus far.

So, once again I have talked myself out of any regrets about not following that career path. I'm glad I wrote this down, as sometimes I do have to go back and read it to remind myself, especially about the camera in the practice toilet...!



Tune in next week for "It's Not Easy Being Clean..."