Zark's

The Amazon Drought

Red and orange identify areas where satellite measurements indicated reduced Normalized Difference Vegetation Index
Image Credit: Boston University/NASA

In standard PowerPoint style, red and orange on the left denote regions of trouble.

River's End tells that a major tributary to the Amazon, the Negro River dropped to a depth of 46 feet, the lowest in history.  NASA photos reveal drought in the Amazon adds that the area of healthy, green vegetation shrunk by an area three times the size of Texas.  The drought of 2010 was four times the size of the last severe drought in 2005.

NASA scientists are concerned that the Amazon rainforest may be undergoing a change from trees to grasslands and savannahs.  Large amounts of carbon would transfer from the rotting trees into the atmosphere.

Amazon Rainforest is Looking a Bit Brown and Wilted explains the elevated concern of scientists.  The 2010 drought has broken, with the rains returning.  But the forest and vegetation has not rebounded with green growth.

Exploring Space-Time

Artist's animation of hot iron gas riding upon a wave in spacetime
Image Credit: NASA

If you recall, Einstein's Special relativity applies to the case of one twin leaving the Earth in a spacecraft that travels nearly at the speed of light.  The twin that stayed on Earth will be very old when the other twin returns.  That explains what it means, but not why it is needed.  Suppose you had two space ships traveling at the speed of light in opposite direction.  If we assume the reference frame of one of the ships, then the other space ship is traveling at twice the speed of light.  But that breaks Einstein's axiom - that the speed of light is constant in every direction.  So the way to fix this conudrum is that time moves much more slowly for objects traveling near the speed of light.

General relativity predicts that time travels more slowly for objects within gravitational fields relative to those outside those fields.  Wikipedia explains that three-dimensional space and time are part of a four-dimensional manifold. On the Earth, when we measure the speed of an automobile around a racetrack, we assume that time measured by the stopwatch is independent of its position. 

Within tremendous gravity, the four-dimensional surface is compact, and closes upon itself.  This is mathematically bizarre, because it breaks causality - future events can effect historical events.  But gravity is really the distortion of space-time by mass, not an independent force. More strange though, is that on Earth, we can move along a single coordinate such as East.  If space-time is a four-dimensional manifold, we should be able to travel along the coordinate of time.  Hence somehow, time travel is possible.

Ethics and Science

This historic 1966 image shows a roller apparatus used in the process of growing cell cultures - the first cell clones.
Image Credit: CDC/ Gerald Taylor, PhD

TED almost always has a thought-provoking, if not challenging talk by a front-runner in their field.  They recently posted Paul Root Wolpe: It's time to question bio-engineering.  He directs ths Center for Ethics at Emory University, in Atlanta.  In the talk, he discusses some  surprising bio-engineering experiments from animal hybrids such as zorse, (zebra and horse), geep (chimera of sheep and goat), and luminescent pets.  Not too far in the future, parents will decide to have glow-in-the dark children.

I have posted in the past about genetically modified salmon, but Paul says we shouldn't be too particularly concerned, because the majority of the food we eat in the U.S. has been genetically modified.  Of course, we have clones of many species, some of which are in an attempt to save a species.  Also, don't forget transgenic pigs which are an attempt to grow human organs for transplantation. 

Many people shrug their shoulders, because after all, mankind has been breeding animals and plants for centuries.  What should give us pause is the things scientists are creating would never appear in nature. 

Several years ago, Paul posted a commentary - Reasons Scientists Avoid Thinking About Ethics.  I encourage you to read it, but the executive summary is:

• I'm not trained in ethics
• My scientific work has little to do with ethics
• Ethics is arbitrary
• Ethicists mostly say 'no' to new technologies
• Others will make the ethical decisions
• The public does not what it wants
• Knowledge is intrinsically good
• If I don't do it someone else will

Mmm.  We are creating a scarier world than we inherited.  It is hard to argue that a transgenic pig is wrong when it can save a life.  Or is the premise that human life is the basis of ethics invalid?

 

Siberian Forests are Changing

Norilsk, a major city in Krasnoyarsk Krai, Russia, and the northernmost city in Siberia, was founded in the 1930s as a settlement for the Norilsk mining-metallurgic complex, sitting near the largest nickel-copper-palladium deposits on Earth.

Image Credit: NASA/GSFC/METI/ERSDAC/JAROS, and U.S./Japan ASTER Science Team

Wikipedia reminds us that Siberia represents 77 percent of Russia's territory, but only 25 percent of the population.  Covering the vast mineral resources are miles and miles of trees.  Until the environment began changing, most of these trees were larch trees.

The larch tree is coniferous, but also deciduous, which means it loses its leaves in autumn.  Those leaves are needle-like, but again, very different from pine trees which keep their needles through the winter.  The wood is tough, and waterproof - highly desired for yachts and building exteriors.

Russian Boreal Forests Undergoing Vegetation Change, Study Shows tells that over the past several decades, pine trees are migrating northward, displacing larch trees.   The pine is less hardy in cold temperatures, but is now able to tolerate the warming Siberian winters.  (A boreal forest is simply a coniferous forest.)

That doesn't sound so bad, but remember, a pine tree does not lose its needles.  What is happening is these new trees are not losing their leaves, so the winter sunlight is being absorbed by the leaves, where previously the sunlight was reflected by the snow underneath the barren branches.  Positive-feedback occurs, because warmer temperatures produce more pine trees, which create warmer winter temperatures.

Interesting, isn't it?  Actually, I have always enjoyed stories of Siberia, and my second novel, Butterflies Escape, begins in the Soviet Union's secret Science City, Akademgorodok.  It was Nikta Khrushchev's dream to out-think the West, and exploit the vast mineral resources that were frozen underneath the Siberian landscape.  He was somewhat prophetic - Russia is selling the mineral resources today, but that constitutes their economy, not the scientific society that he envisioned.

Radiation Effects on the Human Body

Three Mile Island Complex
Image Credit: CDC

Japan Now Fights Radioactive Water explains that seawater radioactivity is 1250 times greater than normal offshore of Fukushima.  To place it in perspective, if you drank 500 ml of the water, you would reach your limit for a year's exposure.

Radioactivity implies ionizing radiation, or the ability to move electrons from their orbits.  That means breaking chemical bonds, which can alter DNA, or other functionality.  Radiation Biological Effects explains there are four different categories of radiation effects upon living cells:

• a) Cells are undamaged by the dosage - if the dosage has a chemical change, it is similar to non-nuclear changes, and the cell is able to tolerate it. 
• b) Cells are damaged, repair the damage and function normally - a cell has extensive repair machinery and can repair even DNA damage. 
• c) Cells are damaged, repair the damage and operate abnormally - life critical functionality might be ruined, or cancers and tumors might result. 
• d) Cells die as a result of the damage - some cells are more susceptible to radiation than others (such as bone marrow).

Exposure (rem)	Health Effect	Time to Onset (without treatment)
5-10	changes in blood chemistry
50	nausea	hours
55	fatigue
70	vomiting
75	hair loss	2-3 weeks
90	diarrhea
100	hemorrhage
400	possible death	within 2 months
1,000	destruction of intestinal lining
	internal bleeding
	and death	1-2 weeks
2,000	damage to central nervous system
	loss of consciousness;	minutes
	and death	hours to days

Credit: EPA

End of the Journey for NASA's Stardust

Artist's Illustration of Stardust
Image Credit: NASA/JPL-Caltech

It was launched on Feb 7, 1999.  Mmm.  I was going to list some highlights from 1999, but Wikipedia recounts it was a particularly tumultuous year - Columbine High School massacre, several plane mishaps, and the Kosovo War.  U.S. women defeated China in the World cup, and Lance Armstrong won his first tour.

But back to Stardust.  The primary mission was to collect comet particles and then return the samples back to Earth via a sample return capsule in 2006.  At that time, NASA re-tasked the spacecraft to fly past comet Tempel 1.  That occurred on Valentine's Day this year, where it was used to survey the comet after the Deep impact mission.

NASA Stardust Spacecraft Officially Ends Operations tells the spacecraft traveled 3.5 billion miles before it finally used up its last fuel in a burn.  NASA scientists wanted to know when fuel ran out, because it helps them develop better estimates of a spacecraft's remaining fuel, since they use a computer model rather than a hardware fuel gauge.  (Apparently it is a difficult problem, determining how much fuel is remaining in a spacecraft's tank.)  After this last burn, NASA officially retired the mission, like yesterday's western cowboy rode into the sunset with the closing credits of the film. 

Women Now Graying Ten Years Earlier

Hair cell of amphibian inner ear
Image Credit: A.J. Hudspeth, MD, PhD

Wikipedia explains that hair color is the pigmentation from hair follicles caused by two types of melanin - eumenalanin (black and brown) and pheomelanin (red).

High concentrations of black or brown eumenalanin results in darker hair color, whereas low concentrations of black result in gray hair.  Low concentrations of brown results in blond hair.  Sounds complex, doesn't it?

The natural changing of hair color with age is called achromotrichia.  As you might guess from the description above, graying occurs when the hair follicles cease producing melanin.  The root cause (no pun intended) is when the melanocyte stem cells die.  (Yes, I know - another pun.)

Women starting to go grey earlier tells that 1/3 of British women have begun to turn gray by the age of 30.  Only 20 years ago, that percentage was only 18 percent.  The hair-care brand, John Frieda, calls this trend - GHOSTS (grey-haired, overstressed twentysomethings). 

Why are today's women going grey at 25? tells that most of the afflicted women believe it is indeed due to stress.  The hair-care company had first suspected that women were simply highlighting their hair.  The research instead, showed that they are covering gray.  The Daily Mail article describes a double-standard for early graying.  Men are called a silver fox, whereas a woman is called 'grandma'. 

Initial thoughts from scientists are that genetics are responsible instead of the environment.  Mmm.  I guess we can't blame Fukushima, yet.

Should We Invest in Subcritical Nuclear Reactors?

Drums of Thorium Stored After Decommissioning the Fernald Project
Image Credit: Department of Energy

Over the past ten days, everyone has received a refresher on the basics of nuclear power plant.  The nuclear reactors at Fukushima are powered by radioactive isotopes of plutonium and uranium.  The process is called a chain reaction because the fission of one atom produces neutrons that scatter into other atoms, producing more neutrons.  Engineers call it a positive-feedback system, because it will continue to grow, limited only by the fissionable material available.  Prior to the first successful chain reaction with the Manhattan Project, some scientists were concerned that a chain reaction might destroy the earth.

As evidenced by the reactors at Fukushima, uranium and plutonium are dangerously unstable - containment and control are necessary.  So maybe we should think about a nuclear reactor that is subcritical - or without external energy applied to it, it simply cools down.  (Yes, nuclear engineers will joking call it a hydrogen fusion reactor, because we have never been able to produce more energy than it consumed, but I digress.) 

Accelerators for America's Future explains that thorium is three to four times more abundant than uranium, and doesn't produce enough neutrons to support a self-sustaining chain reaction.  An accelerator-driven subcritical thorium reactor would achieve chain only as long as the neutron source provided a sufficient quantity of neutrons.  If something like a tsunami or earthquake interrupted operations, the neutron source would be switched off (manually or naturally) and the chain reaction would cease. 

Essentially, this type of reactor could be called an energy amplifier, and would produce about 100 times as much energy as it consumed.  The thorium reaction produces much less plutonium as conventional reactors today.  It does produce highly reactive U²³², but again, it cannot achieve a runaway chain reaction.

Safe nuclear does exist, and China is leading the way with thorium tells that China has a serious interest in this alternative nuclear technology.  The Telegraph's report explains that scientists at Oak Ridge, TN, proposed the thorium reactor in the early 1960s, but never commercialized the technology.  China's Academy of Sciences has embraced the idea, happier with the safety of the thorium reactor.

Mmm.  Popular Science reminds us that thorium is named for the Norse god of thunder.  Subcritical hydrogen fusion has not been particularly successful.  I wonder whether it would be more thunder than rain.

(In case you are interested about the photograph, Fernald was a uranium processing facility located 18 miles northwest of Cincinnati, OH.  After 37 years of operation, it was retired in 1989 and placed into cleanup.)

New Delivery Mechanism for Alzheimer's Sufferers

PET Scans of Two Brains - One normal, and one with Alzheimer's Disease
Image Credit: National Institute of Aging

A vesicle is a bubble of liquid within a bubble of liquid.  Practically, they are a membrane-enclosed sack that can transport substances.  They are used by a living cell to organize its content.  No doubt you remember seeing vacuoles underneath a microscope, where a vacuole is used for nutrient storage.

An exosome is a specialized vesicle about 1000 times smaller than the diameter of a human hair, 50 to 90 nm.  Researchers believe they are used for selective removal of proteins within the cell's outer membrane wall. 

Breakthrough in delivering drugs to the brain explains that scientists at the University of Oxford have discovered exosomes can cross the blood-brain barrier.  The latter is a complete separation of the blood that circulates in most of our body from the blood in the brain.  This protects the brain from most bacterial infections, but also prevents treatment of the brain with drugs. 

The Oxford team harvested exosomes from mice and filled them with proteins that would deactivate a suspected Alzheimer's gene, BACE1.  These were inserted back into geneticially modified mice with the equivalent of human Alzheimer's disease.  The treatment reduced the Alzheimer's gene activity by 60 percent.

Researchers are excited by the results, because they could lead to future treatments for humans on Alzheimer's which is expected to double to 66 million cases by 2030.

Why Do We Care About Network Neutrality?

First locomotive to cross the newly construdted railroad bridge spanning the Han River at Seoul, Korea. 19 Oct 1950
Image Credit: U.S. ARMY

Wikipedia explains network neutrality is a principle for no restrictions by internet service providers and governments on content, sites, etc.  Berners-Lee warns ISPs on net neutrality argues that restrictions on content and bandwidth would ruin the innovation and creativity experienced on the internet during the past two decades.  (Berners-Lee is the inventor of the world-wide web.) 

House Committee Votes to Approve Resolution Against FCC Net Neutrality Rules tells that the House is attempting to ditch the FCC's resolution on net neutrality.  But as The FCC's Net Neutrality Announcement: The Good, The Bad, and What It Means for You, explains that ISPs are prohibited from favoring their content over someone else's content.  They are free to create bandwidth tiers, which for cable companies, essentially does that.  A bandwidth cap could make NetFlix prohibitively expensive compared to the cable company's own offered content.

Mmm.  In some ways, but not all, this resembles the tactics of the railroads in the late 1800s.  Their fares determined which businesses succeeded and which failed, because the fares were not the same.  This was how Standard Oil became such a monopoly.  At one time, it could ship a barrel of oil $1 cheaper than its competitors.  But to make things worse, $1 of the competitor's fare went directly to John D. Rockefeller's corporation.  Little wonder that Standard Oil drove competitors out of business.  Other businesses also created preferred deals with the railroads.

Eventually, laws were passed that the railroads had to be common carriers with the same rates for everyone. 

With the internet, there is a cost for the ISPs to accommodate bandwidth-hungry customers, particularly on the last-mile connections to the households and businesses.  So it is a little different from the railroad monopolies in that internet content providers expect the ISPs to transport their product for free.  But we are also running parallel to history in permitting ISPs to have bandwidth caps that do not include their own content.

It is a complicated problem ...