Posted by: scienceguy288 | November 8, 2009

A Strange System: Food: Hard Travelin’ Blues

You walk through the aisles of your local supermarket.  Apples in June.  Watermelons in February.  Oranges in December.  Weird star fruit in….well I don’t actually know if star fruit have a picking season.  So how do we have these fruits and vegetables when it is not time for them to be picked.

Most of our food doesn’t come from the good ol’ USA.  As I previously mentioned, we mainly grow corn.  Most of that is used for biofuels and livestock feed.  So where do we get all this stuff?  Well, where is it warm and rainy all year-round (and cheap to grow)?  Thing South.  We get a vast majority of our produce (when not in season) comes from Mexico, Brazil, Columbia, and Brazil.  If you have time, I suggest you actually go to your local supermarket and ask the manager from where the produce is coming.  99 times out of 100, you will get a blank stare.

As a nation, we have become so disconnected from the very sustenance we need for survival.  Most urbanites think farmer as being synonymous with country bumpkin, redneck, hillbilly, or quaint.  There is a social stigma to be a farmer.  But should those farmers disappear, well, the high and mighty urbanites are in for a world of hurt.  In fact, this may not be as strange as one would think.  Since 1979, 300,000 small farms have disappeared in the United States, and since 1946 the number of people who make their living by farming has been cut in half. Increasingly, large companies like Monsanto and Carghill take over and force farmers out of their land.

Farmers' Numbers Decrease

Farmers' Numbers Decrease

Back to the food.  So these crops are being grown in countries far away from all of us.  The workers who are spraying the pesticides we previously mentioned, working long hours in the hot sun are probably not being paid very well.  But that is not a problem: we get our watermelons cheap!  The crops are finally picked.  Now what?  The crops are put in an air-conditioned airplane and flown to packaging and distribution centers throughout the United States.  Then, they are shipped in air-conditioned trucks all over the country on our wonderful highway system.  This is hugely energy intensive.  It is estimated that the average American family’s meal has traveled almost 10,000 miles before it reaches the plate (in December, to be fair).   Scientists have clocked energy usage as being 10 calories of fossil fuels for 1 calorie of food.  Talk about inefficient.

The Cosmic Perspective

Perhaps for the purposes of this series the Cosmic Perspective should be retitled to What You Can Do.  Oh well, too late.

If ever there was a simple way to make a difference it is to: buy local and in season!  Simple!

Don’t buy those apples in June or watermelons in February.  Eat what is available in your zone when you plan to eat it.  That might mean doing without some things.  Unfortunately, most Americans are still in the mentality that they want it all and they want it now.  So visit your local farmer’s markets.  Not only will you help support the local economy (that is all the rage), but you will be eating better: better for you and for the environment.  Build a relationship with those great folks who grow your food.  Check out this link to find more links regarding local eating:

http://www.animalvegetablemiracle.com/LocatingLocal.html

I don’t mean that you have to drop oranges altogether.  I have eaten a star fruit.  Guilty as charged.  But all good things in moderation.  Once in a while is fine, every day is where the problem arises.

In her book, Animal, Vegetable, Miracle, Barbara Kingsolver notes,

“The main barrier standing between ourselves and a local-food culture is not price, but attitude. The most difficult requirements are patience and a pinch of restraint – virtues that are hardly the property of the wealthy. . . We’re raising our children on the definition of promiscuity if we feed them a casual, indiscriminate mingling of foods from every season plucked from the supermarket, ignoring how our sustenance is cheapened by wholesale desires. Waiting for the quality experience seems to be the constitutional article that has slipped from the American food custom…We have the illusion of consumer freedom, but we’ve sacrificed our community life for the pleasure of purchasing lots of cheap stuff. Making and moving all that stuff can be so destructive: child labor in foreign lands, acid rain in the Northeast, depleted farmland, communities where the big economic engine is crystal meth. We often have the form of liberty but not the substance.”

Posted by: scienceguy288 | November 2, 2009

A Strange System: Food: Blue Baby Blues

Time to get back on the horse after a week of midterms.

Nitrogen was the primary limiting nutrient in terrestrial ecosystems.  Nitrogen levels could be increased by using composted organic material, but that took a long period of time and was hard work.  Keep that in mind.  World War II is raging and ammonia is needed to create munitions.  Cue Fritz Haber and Carl Bosch.  They came up with the aptly named Haber-Bosch Process which synthetically fixes nitrogen by reacting nitrogen gas and hydrogen gas over an enriched iron catalyst to produce ammonia.  Before this, ammonia was difficult to produce on an industrial scale because atmospheric nitrogen, N2, contains resilient triple bonds. During the process, N2 gas is combined with H2 gas at high pressures and high temperatures.  This reaction takes place in the presence of a catalyst, usually some sort of iron, which lowers the activation energy required to break chemical bonds, allowing the reaction to happen more efficiently.   After all is said and done, we have gaseous ammonia which can be condensed into liquid ammonia.  This, in turn, can be used in munitions.

 

Haber Bosch Process

Soldiers were coming home after the end of the second World War.  Everybody wants to forget about the staggering losses of life that took place during the War.  But, the chemical companies which supplied chemicals needed for weapons during wartime have a problem.  No war means no sales.  They had to adapt to a new market quickly.  So, they came up with a brilliant idea: they would work to create chemical fertilizers and pesticides.  I bet you didn’t know that chemicals used in wartime could be so easily converted to fertilizers and pesticides (take Agent Orange and DDT, for example).  These chemicals greatly improved our agricultural output.  In fact, the increases in crop yields were so drastic that it is still called the Green Revolution.  Crops were specifically chosen and bred so that they could tolerate high nutrient levels that are not normally present in nature.  The problem is that the Green Revolution was not very green.

I don't even have words for this...

One cannot be led to believe that pumping inordinate amounts of  nitrogen fertilizer into the soil is natural.  And since the soil cannot possibly hold all of it, much is lost when irrigation (more on that next time) percolates through the soil, flushing many of the nitrates into streams, rivers, and groundwater.  Oops.  As I mentioned before.  Nitrates from fertilizers often flow into rivers which dump the excess nutrients into bodies of water, creating algal blooms.  The algal blooms don’t have all that much oxygen in the rather warm waters (warm liquids don’t hold gases as well as cold ones (why pop is better cold)), so they die relatively quickly, but not before using up all of the oxygen in the water, creating a dead zone.

The nitrates can also seep into ground water which is then used for drinking, bathing, washing dishes, etc.  Not surprisingly, this is not great for your health.  In fact, excess nitrates have been linked to many diseases, particularly in children, whose small bodies cannot tolerate as many chemicals.  Probably the most horrifying disease is Blue Baby Syndrome, or Methemoglobinemia, which results in decreased oxygen carrying capacity of hemoglobin in babies leading to death or other birth/developmental disorders (similar diseases can be caused by excess nitrates from cesspools of fecal matter from factory farms as described previously).

Pesticides are used extensively.  Most of us use them without a second thought.  But perhaps, we are doing more harm than good.  Imagine you are spraying some pesticides to kill off some Japanese beetles (the little iridescent buggers which eat all of your flower leaves).  You kill off most of them, but some survive.  They have a resistance to the chemical.  Now, these beetles reproduce and pass on their resistance to some of their offspring, so we spray more and more, to kill fewer and fewer beetles.  That is the story since the beginning of time: a process of coevolution between pests and pesticides.  Our response is to either increase the dosage of pesticides, or increase the toxicity of the chemicals, neither of which is good in the long run.  Because of genetic resistance, farmers can pay more and more for pest control programs that become less and less effective.

Another big problem with these pesticides is that they are nonspecific: they will kill most of the pests, but many of the pest’s natural predators as well!  Not to mention, when the pesticides are sprayed, some of the chemicals will end up in nearby natural areas like forests and streams, which will kill many species in the nearby area, limiting biodiversity.It turns out that pesticide use has not reduced US crop losses to pests, mostly because of genetic resistance and reduction of natural predators.  I am sure we all remember the effects of DDT as presented by Rachel Carson in Silent Spring.


Toxic Chemicals Being Sprayed

The Cosmic Perspective

Today, 50% of the world’s population is alive thanks to synthetic fertilizers and pesticides.  Don’t forget to couple that with the 40% alive thanks to antibiotics.  If the fact that fertilizers and pesticides are destroying the earth didn’t convince you that there is a problem, perhaps you wonder who is spraying these toxic chemicals.  More often than not it is migrant workers who are given little to no protection, causing serious medical conditions.  So what can we do to limit our and the earth’s exposure to pesticides?  Grow some of your own food using organic methods.  Wash and scrub fresh fruits and vegetables.  Eat less meat.  And, if you think that you cannot get around using some sort of pesticides, here are some tips.  Rotate the types of crops and adjust planting times to fool the pests.  Provide homes for pest enemies.  Inplant genetic resistance.  Use pheromones to lure pests into traps or attract natural predators into crop fields.  By changing our habits, if only a little bit, we can make a big difference.

Posted by: scienceguy288 | October 25, 2009

A Strange System: Food: Too Corny

Too Corny

Corn is a wonderful vegetable.  Admittedly, the stuff we consider corn is actually maize, but I’m not here to argue semantics.  The kernel of maize is a mature ovary of fruit fused with a seed coat.  Corn can be eaten raw, cooked, or ground into flour for bread.  Good stuff this corn.  Perhaps that is why so many Native American cultures used it as the basis for their agricultural system.   However, we decided that there can’t be too much of a good thing.  Too bad that’s not true.

A cornfield

A cornfield

If you drive through the Great Plains states, you will be seeing a ton of cornfields.  In fact, that is probably the only type of farming you will see.  We have turned our central Great Plains into a monoculture, where one crop dominates.  This causes a number of problems.  First, this limits the genetic variability of the crops.  If a blight or fungus decided to mosey its way into a corn field and do some damage, you can bet that the whole system is likely to fail, because now, certain plants that are resistant to this infestation are gone.  It is all the same.  Second, it depletes the soil.  When the early white settlers were moving into the Great Plains, the grass had root systems several feet deep.  There was a huge amount of top soil.  But due to constantly farming the same thing and not rotating crops, we have decreased the topsoil levels to a paltry few inches.  Where did this soil go?  Into the streams.  Where do the streams go?  In that area, all roads may lead to Rome, but all streams head to the Mississippi River.  And where does the Mississippi River go?  Unless you flunked seventh grade social studies, you know that it empties into the Gulf of Mexico.  These sediment deposits disrupt the natural ecosystem of the Gulf.  They also carry with them nitrates from fertilizers (more on that in the next segment), which create huge algal blooms.  The algal blooms don’t have all that much oxygen in the rather warm Gulf stream waters (warm liquids don’t hold gases as well as cold ones (why pop is better cold)), so they die relatively quickly, but not before using up all of the oxygen in the water, creating a dead zone.  This is a continuous cycle of nutrient depletion and algal blooms, creating a large dead zone at the mouth of the Mississippi.

And we eat it.  Corn, that is.  Well, perhaps eat is isn’t the best word.  We ingest it in some form.  Corn is convertible into tons of cool food additives, like high fructose corn syrup, dextrose, corn starch, corn oil, and many more of your favorite food label regulars.  We find it everywhere.  Why?  (That one question is so important).  It is common because it is cheap.  Why?  One word: subsidy.  Why?  Because big companies love to use corn.  Why?  Aha, now that is the right question.  The corn kernel is essentially a packet of starch that can be broken down and rearranged as all of those additives, sweeteners, and preservatives listed above.  So to keep their costs down, companies need to keep corn cost down.

Brought to you by the letter c: Corn

Brought to you by the letter c: Corn

Not only is corn convertible to foodstuffs, it can be made into, drum roll please… ethanol!  Ethanol amongst the dumbest ideas I ever heard, and to think that I once believed it had potential.  Right now, whether you like it or not, your gas is 10 percent ethanol.  It’s required by law.  Ethanol is a renewable bio-fuel.  It may burn a bit more cleanly than gas, but, depending on which study you read, some scientists claim that you need to put 1.2 calories of corn into the system to get 1 calorie’s worth of ethanol (this depends on what you consider a cost of farming and producing for corn ethanol.  Some analysts believe tractors fall from the sky so they don’t need to be considered in cost analysis).  It doesn’t take a rocket scientists to do the math.

A factory farm dairy feedlot

A factory farm dairy feedlot

Cows are grazing animals.  They are supposed to eat grasses.  So when farmers take cows to pasture, they can have some fun, eat some grass, chew some cud, poop some poop (fertilizing the soil so more grass grows) and everybody goes home happy.  Now, cut to the factory farms.  Cows stand with little to no room to move, knee deep in their own feces.  Factory farms use corn to feed all these cows.  But wait, didn’t I just say that cows are supposed to eat grasses?   Corn is not a natural part of their diet, and it completely messes up their digestive system.  So now what are we going to do with all this fecal matter?  Well, the brilliant solution we have come up with is to create giant cesspools of crap.  These, in turn, seep into the ground water and streams, killing those systems, much like nitrates from fertilizers created a dead zone in the Gulf.  Yum.  Good, clean water.  Also, whenever we divert corn to ethanol, or to livestock feed, we divert it from people who need it for food.  And as the amount of corn being grown for food decreases, the prices increase, causing many people to go hungry.  Seems like a system designed to fail!  It gets better.  We use gas with ethanol in it to ship corn from the Plains to the factory farms in the Carolinas and the Dakotas, and then the cows to the processing plant, and then your local supermarket.  Every calorie of commercial food you eat expends almost 10 fossil fuel calories.  Talk about inefficient.

The Cosmic Perspective

But, you say, how can I make a difference?

A feedlot

A feedlot

You have buying power.  The purchases you make directly influence companies and our governmental policies.  Buy grass fed beef instead of factory farm meat if you have the money to do so.  It will have less fat and will taste better!  Or, eat less meat.  I am not asking you to become vegetarians.  In fact, I think vegetarianism is unhealthy (The Vegetarian Myth by Lierre Kieth) and often committed to for the wrong reasons.  The clear-cutting of forests to make room for fields for cattle, the environmental impact of slaughterhouses, transportation costs and the sheer amount of methane gas emitted by cattle herds, is damaging to the planet.  Also, eating less meat will positively affect our health in the long run.  The average American obtains 80 percent of their caloric intake from meats, 7 percent from pop and processed foods, and 3 percent from plants.  Is it any surprise that 30 percent of the population is obese, 8 percent have diabetes and 1 in 5 adults have high cholesterol.  400,000 people in the US die from obesity related diseases each year.  Type II diabetes was once thought to be only found in adults.  Now, this generation is set to be the first to have a lower life expectancy than their parents.  We should try to move towards 45-5-50 with regards to our caloric intake.  This will help us lower our cholesterol, blood sugar, and weight.

But it costs so much.

Well, thanks to those nice government subsidies, corn fed beef and corn products can be sold cheaply.  If the actual cost of those corn products was displayed in the supermarket, people would never buy them.  Think of all the water, fertilizers, pesticides, energy, and man hours went into making those foods.  I think that may be worth a bit more that what the supermarkets are saying it is worth.  Not to mention the environmental costs!

Think about it.

Posted by: scienceguy288 | October 18, 2009

New Series: A Strange System: Food: The Stage is Set

It has been a while since my last official series on this blog.  I have been reading several books and watching several films on this subject.  Food is an important facet of our existence, for obvious reasons.  And yet, for some strange reason, few of us know from where the things we put into our body come.  A little disclaimer first: I am not a nutritionist, I am simply a concerned citizen who wants people to start asking some very important questions.  There are many people who know much more about this subject than I do, and fortunately for you, they have written extensively about their knowledge.  If you are interested in this series, I suggest you read the writings of Michael Pollan, Frances Moore Lappe, Barbara Kingsolver, Eric Schlosser, and/or Vandana Shiva.  So without any further ado, I present: A Strange System: Food.

The Stage is Set

When you picture a farm, what do you see?  Probably chickens and chicks pecking around for seeds underfoot, cows sitting in a pasture, contentedly mooing, perhaps a farmer, chewing a piece of straw, of course, checking to see if there are any weeds choking out his corn crop.  This is the typical, idyllic scene we all grew up with, and like most things we grew up with, it is largely dead wrong.

We live in a time when food production has shifted from the hands of farming families to agribusiness conglomerates.  Businesses most of us don’t even know exist, like Monsanto and Cargill.  The whole food system revolves around these players.  The web they weave is so thick and tangled that I almost don’t know where to start.  But perhaps, I should begin with the beginning.

When humans were first evolving on the African Savannah, we had appetites similar to those we have today.  The appetite was developed to encourage people to eat what they needed.  The African Savannah had plenty of grazing animals for us to kill and eat.  This gives us our proteins, minerals, and some vitamins.  There are also plenty of edible roots, nuts, and plants which provide us with fiber, oils, and more minerals and vitamins.  However, there was a problem.  Humans need some fat to survive, and grazing animals, which eat grass (more on that later), don’t have too much of that.  It was also rather difficult to find salt and sugar.  So, if you found something with salts or sugars, evolution encouraged us to gorge ourselves.  And so, we spent our formative years as a collective species discovering new ways to provide our communities with food.  We learned how to hunt more efficiently; how to gather edible plants.

Fast forward to about 11,000 BC.  Scientists are pretty sure that humans learned how to domesticate certain plant species at this point in time.  Annuals like peas and wheat were being domesticated in area of the Middle East known as the Fertile Crescent.  There, the dry-summer allowed for a long growing period and variety of elevations led to a great number of plant species being domesticated.

Skip to the next scene when, about 1000 years later, in 10,000 BC., animals like the sheep and goat were being domesticated.  Pigs, cows, and chickens followed in the subsequent millenia.

The domestication of plants and animals was probably the single most important event in the evolution of civilization. Slowly but surely, as we began to farm, humans shifted from being hunter-gatherers to a settled agricultural society.

Ancient Agriculture

Ancient Agriculture

Through the Middle Ages, everyone seemed to either have a farm or know a local farmer who could produce food for them.  Farming methods were being fine tuned.  Farmers in drier regions developed hydraulic irrigation systems.   People explored the reasons why farming different crops worked better in one place than another.  They expanded the number of species of plants being grown.  Crop rotation was developed.  The Chinese developed a moldboard plow which helped till the soil leading to better crop yields.  Things were on the up and up, but progress was relatively slow.

Once again, we step into our little time machine and zoom to 17th century England.  The Agricultural Revolution is about to begin.  One of the first big changes was enclosure.  Before this point in time, most agricultural systems worked in an open field system.  Each farmer grew subsistence levels of crops and fed their livestock on tracts of land nobody really owned.  Then, come the 17th century, wealthy farmers began buying up the land.  This led to most farmers losing their land.  Mechanical advancements came soon after.  Jethro Tull, the inventor, not the band, invented a seed drill: a mechanical seeder which distributed seeds evenly and efficiently across a plot of land.  This was much faster than spreading seeds by hand.  Joseph Folijambe invented the Rotherham plow in 1730, the first commercially available iron plough in Europe.  In 1786, Andrew Meikle invented a threshing machine.  When steam engines came out on the market in the 1850’s, they were quickly put to use for plowing and digging in agricultural settings.  Excellent news.   Food production skyrocketed, and with it, population.

The English Agricultural Revolution

The English Agricultural Revolution

We have one more stop for today.  Let’s travel to the United States around 1920.  Scientists have identified nitrogen, potassium, and phosphorus as the main factors behind plant growth.  So to max out crop yields, they create synthetic fertilizers leading to more intensive agriculture.  Vitamins and antibiotics are discovered.  This allowed livestock to be raised inside, reducing their exposure to the harsh side of Mother Nature.  They could be fed these antibiotics allowing for livestock to be grown in concentrated areas without the risk of spreading disease.  They also grew larger and faster.  After World War II, everybody just wanted to kick back.  But the chemical companies have a problem.  They just spent the last six years producing chemicals to be used in the war.  No war means no sales, so they convert their factories to produce synthetic pesticides.  An interstate highway system is constructed allowing for food to be distributed all across the country.  Oil is plentiful and cheap, so it’s all systems go.  Agricultural production across the world doubled four times between 1820 and 1975 to feed a global population of one billion human beings in 1800 and 6.5 billion in 2002. Oddly enough, during this same time, the number of farmers actually farming dropped.  Well, the stage is set.  We’ll return to the second act in our next installment.

Posted by: scienceguy288 | October 11, 2009

Science and Soul: Earthquakes

This year’s Nobel Prize in medicine was awarded to three Americans for their discovery of the importance of telomerase in the genetic operations of cells, an insight that has inspired new lines of research into cancer.  Elizabeth H. Blackburn of UC San Francisco, Carol W. Greider of Johns Hopkins School of Medicine, and Jack W. Szostak of Harvard Medical School were the winners.

Cellular Biology Review: Telomerase is an enzyme that adds specific DNA sequence repeats to the 3′ end of DNA strands in the telomere regions, which are found at the ends of eukaryotic chromosomes.  The telomeres are known as cellular clocks.  As they degrade, the cells become closer to death.  Grey hair is caused by telomere degradation to a certain degree.

Politicians’ low aims regarding climate change reform could be too little, too late, according to a new historical record of carbon dioxide levels.  Using ocean sediments to research carbon dioxide levels, scientists determined that the numbers many politicians want to reach are not extreme enough.

Apocalypse Soon: Sea levels could become 25 to 40 meters higher than today’s levels.

Scientists have discovered how the two meter long strands of DNA code (one cell) are packed into the cells’ nucleus, which is 1/100 millimeter in diameter.  The genes are organized into a tight, knotted ball to do so.

Fuzzy Math: Unravel your DNA and it would stretch from here to the moon: 3.85 × 108 m.

Cool Creature

A small glass lizard

A small glass lizard

A glass lizard (Scheltopusik) is commonly referred to as the snake lizard, because it resembles a snake.  This lizard has no legs, but have a characteristic head shape, movable eyelids, and external ear openings.  These characteristics are present in lizards, not snakes.  They can grow up to 4 feet long.  They will commonly eat insects and can be found in Southeastern Asia, North Africa, and the Southern United States.

Feature Story: Earthquakes

Admitedly, this post will be late, but still pertinent. More than 1,100 people have been killed and thousands more injured by the strong earthquake that struck the Indonesian island of Java. The quake, which occurred on the 3oth of September, measured 7.6 on the Richter scale.  To put this in the perspective, imagine 2 atomic bombs being dropped simultaneously.  This is the amount of destruction rained down on this little southeast Asian island.  Fortunately, the earthquake’s epicenter was in the ocean, which created a buffer for the island.  Geologists have long warned that Padang – a city of 900,000 people – could one day be completely destroyed by an earthquake because of its location.

Unfortunately, Java sits in the Pacific Ring of Fire, an area famous for its high frequencies of earthquake and volcanoes. About 90% of the world’s earthquakes and 80% of the world’s largest earthquakes occur along the Ring of Fire.  The ring consists of a 40,000 kilometer horseshoe shape where tectonic plates jut up against one another.  The Western portion of the ring, where Java is located, is made up of several smaller plates which are all shifting on the earth’s liquid mantle.  Usually, during an earthquake, one of these plates will dip at a fault and the other will rise: a dip-slip.  An earthquake is essentially seismic waves created by the release of energy.  This jerk causes the forces we feel: tremors, tsunamis, and landslides.

Cosmic Perspective

We live on a planet that is constantly in motion.  Not only are we hurtling through space, the ground below us moves, slowly but surely.  Sometimes, these slight movements create huge effects.  When this happens, humans think of this as nature being against us.  Nature must be out to get us because something in nature caused human death.  And yet, I feel that humans pose a greater problem for humanity’s survival.  We do more to kill ourselves off than any natural disaster.  People must realize that nature is not inherently against or for us.  Nature is.  To quote The Big Lebowski: “The dude abides.”  Nature’s forces reigned before we came into being and will reign afterwards as well.

I suppose this cosmic perspective would not be complete without a public service announcement.  The amount of destruction in Java is terrible.  We must help those affected by the tragedy.  Do what you can, donate money, time, prayers, a smile.  I like this Arlo Guthrie story:

Do you know the story of Joseph, you know, in the Bible.  Well, Joseph is looking for his brothers, who aren’t where he thought they’d be, and while Joseph is going down the road, he asks some dude where his brothers were.  Some unnamed person working in a field points and says, “They’re that way.” When he catches up to them, the brothers send him to jail in Egypt. While there, he helps his cellmates with troubled dreams. One cellmate goes on to advise the Pharaoh and when the Pharaoh has bad dreams, Joseph is summoned, and he helps predict a drought and helps Egypt prepare for it. From Joseph derives Moses, and from Moses comes the whole line of people down to Jesus, and all that — and it’s all because of that one guy who said, “They went that way.”  Remember, if the world was wonderful: everyone has a BMW, health insurance, a nice family and a job, one would have to go a long way to make a difference.  But in a world that sucks, like this one, well…there was never a time like this: where you could do so little and get so much done! And you can do so much with a hug, a gentle word, or a smile when you don’t feel like smiling.

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