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… by Michael Graham Richard, Ottawa, Canada on 03. 3.10


Lemon leaf with interconnected loops. Photo: RU

A team of biophysicists at Rockefeller University recently published a paper in Physical Review Letters about a new way to design distribution networks based on the veins that carry water and nutrients in most tree leaves. This is a great example of biomimicry! Evolution by natural selection maybe be blind, but it has had billions of years of trial-and-error to figure out efficient and robust ways to do things. The interconnecting vein loops in leaves are a good example of that, and we can learn from them.


Ginko leaf, without interconnected loops. Photo: RU

“Operations researchers have long believed that the best distribution networks for many scenarios look like trees, with a succession of branches stemming from a central stalk and then branches from those branches and so on, to the desired destinations. But this kind of network is vulnerable: If it is severed at any place, the network is cut in two and cargo will fail to reach any point “downstream” of the break.”

A good example of that can be seen on the two pictures in this post. The big dots are damage in the network. In the pic on top, you can see that the flow isn’t stopped, and can go everywhere in the network. In the second pic, the flow is stopped everywhere downstream of the damage point.

“Operations researchers have appreciated that these redundancies are an effective hedge against damage. What’s most surprising in the new research, according to Marcelo O. Magnasco, head of the Laboratory of Mathematical Physics at Rockefeller University, is that the complex network also does a better job of handling fluctuating loads according to shifts in demand from different parts of the system — a common real-world need within dynamic distribution networks.”

This kind of network full of loops can also be found in the blood vessels of the retina, the architecture of some corals, and the structural veins of insect wings.

It remains to be seen if the benefits of more robust and easy to balance networks will outweigh the negatives (it would probably be more expensive), but I think resilience and robustness are worth a lot since our society is so dependent on these networks.

For something a bit similar, check out how slime mold can help design public transit networks.

Via Physical Review Letters, Rockefeller University

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by Michael Graham Richard, Ottawa, Canada on 03. 3.10

Lemon leaf with interconnected loops. Photo: RU

A team of biophysicists at Rockefeller University recently published a paper in Physical Review Letters about a new way to design distribution networks based on the veins that carry water and nutrients in most tree leaves. This is a great example of biomimicry!

Evolution by natural selection maybe be blind, but it has had billions of years of trial-and-error to figure out efficient and robust ways to do things. The interconnecting vein loops in leaves are a good example of that, and we can learn from them.


Ginko leaf, without interconnected loops. Photo: RU

“Operations researchers have long believed that the best distribution networks for many scenarios look like trees, with a succession of branches stemming from a central stalk and then branches from those branches and so on, to the desired destinations. But this kind of network is vulnerable: If it is severed at any place, the network is cut in two and cargo will fail to reach any point “downstream” of the break.”

A good example of that can be seen on the two pictures in this post. The big dots are damage in the network. In the pic on top, you can see that the flow isn’t stopped, and can go everywhere in the network. In the second pic, the flow is stopped everywhere downstream of the damage point.

“Operations researchers have appreciated that these redundancies are an effective hedge against damage. What’s most surprising in the new research, according to Marcelo O. Magnasco, head of the Laboratory of Mathematical Physics at Rockefeller University, is that the complex network also does a better job of handling fluctuating loads according to shifts in demand from different parts of the system — a common real-world need within dynamic distribution networks.”

This kind of network full of loops can also be found in the blood vessels of the retina, the architecture of some corals, and the structural veins of insect wings.

It remains to be seen if the benefits of more robust and easy to balance networks will outweigh the negatives (it would probably be more expensive), but I think resilience and robustness are worth a lot since our society is so dependent on these networks.

For something a bit similar, check out how slime mold can help design public transit networks.

Via Physical Review Letters, Rockefeller University

More on your ‘cookprint’.

These healthy eco-friendly kitchen gadgets and appliances will save energy.

By Ronnie Citron-Fink
Rhinebeck, NY, USA | Wed Feb 17, 2010 11:30 AM ET

©iStockphoto.com/Thinkstock

READ MORE ABOUT:
Eco-Friendly Kitchens | Energy Efficiency | Green Appliances | Green Home | Green Your Electricity | Home Energy Use

Would you like to cut your electric bill every month? If you’re like me, you have drawers and kitchen cabinets full of gadgets and small appliances. In an effort to pare down and conserve energy, resources and cash, which of these energy sucking kitchen wonders should you ditch (donate away) and which should stay?

WATCH VIDEO: Emeril’s Vermont Adventures

First, let’s consider at the materials and resources that use energy to prepare a meal. While the term “cookprint” is often used to remind us to eat more plant-based, locally grown and sustainable food, it also represents which appliances and gadgets to cook with. Consumer Reports chose “cookprint” as a top buzzword to describe the energy needed to prepare the food we eat.

“That energy use encompasses the appliances and techniques used to prepare and store food, though the management of leftovers and food waste also factors in–you lower your cookprint by composting rather than tossing scraps into the trash.”

Ditch These Kitchen Appliances and Gadgets

1. Coffee Grinder
OK, it’s early in the morning and it’s awfully easy to plug in the coffee grinder to pulverize fresh beans. Just think how much faster you’ll wake up if you have to do it yourself. Bodum makes preparing and drinking coffee a stylish experience. Check out their hand-crank coffee-grinding beauty.

2. Can Opener
Jaymi has written about electric can openers before and she makes the important point that, “Electric can openers are handy but they don’t save time or effort when compared to a quality manual can opener.” Classic swing-away can openers get the job done.

3. Electric Knife
My mom’s generation swears that the electric knife must come out when the Thanksgiving turkey is ready to curve. But really, why use an electric one when a nice sharp knife can do the same job? Try a hand-held knife sharpener and a good knife.

4. Juicer
Are you surprised to find an electric juicer on the list? This is an easy switch that won’t screw up your healthy juice regimen. Hand-held juicers require a little muscle, but they produce big energy savings. Here are some hand-held juicers to choose from.

5. Electric Mixer and Stick Blender
An electric stick immersion blender has a single mixer attachment, so to make something like whipping cream, a hand-held mixer is your best bet. The old fashioned, quiet hand mixer works like a dream. Often you can find these in antique stores with wooden handles.

Keep These Appliances and Gadgets in Your Kitchen

1. Rice Cookers
Although rice cookers use electricity, they are an eco-friendly alternative to firing up your stove to make rice. Finding a rice cooker with a stainless steel–not “non-stick”–insert is the healthiest choice, because most “non-stick” pots are made with Teflon or aluminum. Teflon contains PBDE, a prevalent contaminant known to cause to the human body and the environment. Here are a bunch of rice cookers with stainless steel inserts.

2. Countertop Grills
These grills are inexpensive and an energy-saving solution to turning on a stove when you want to just make, say, a grilled cheese sandwich. Be aware that George Foreman and similar grills can be coated with Teflon. What’s an eco-cook to do? Get a stainless steel countertop grill.

3. Waffle Irons
The same advice applies for waffle irons as grill pans, especially if you eat waffles often. We have an old, old cast iron waffle iron that makes the best waffles. If you can’t score one of those, I would suggest finding a secondhand waffle iron with cast iron inserts.

4. Hand-Crank Blender
Again, the older “historical technology,” does a fine job. TreeHugger posted on a hand crank travel mixer, and here are some other crank blenders.

5. Mortar and Pestle
A mortar and pestle can be a manual food processor. It’s been used for centuries to make everything from ground spices to mayonnaise. The mortar and pestle’s best feature: It will never require replacement parts.
Are you seeing a trend here? The oldies-but-goodies are making a strong comeback. And making these small changes can significantly lower your cookprint.

More on your ‘cookprint’.

These healthy eco-friendly kitchen gadgets and appliances will save energy.

by Lloyd Alter, Toronto on 03. 2.10

Cash for Caulkers

President Obama is set to announce a new residential renovation funding program that they call a “triple win”: a jolt to the sickly construction industry, saving Americans money on their energy bills and reducing dependence on oil and other fossil fuels. Last month they might have called it a “quadruple win” and mentioned greenhouse gas reductions, but they don’t do that any more, Senator Inhofe would complain.

If they do it right, the six billion dollar program can create a lot of jobs; caulking and sealing is labor intensive, and can put a lot of people to work. But with the power of modern media, it is really easy to do it wrong.

When Planet Green started out, we did a series of posts based on a terrific document prepared by the Rocky Mountain Institute: Cool Citizens: Everyday Solutions to Climate Change: Household Solutions, that looked at the cost of a renovation item, the amount of energy and carbon it saved, and calculated the bang for the buck. It is now eight years old and much has changed, as fuel got more expensive and compact fluorescents a lot cheaper. But the order is probably still pretty much correct.

Some of our Planet Green posts following the RMI order:

Where To Start
Get a Programmable Thermostat
Stop the Air Leaks
Add Attic Insulation
Insulate Your Water Heater
Add Attic Insulation
Install Efficient Showerheads
Install Faucet Aerators

Notice that window replacement is nowhere on the list; it is so far down the list in terms of energy saved per dollar spent that it is almost off the bottom. If I were handing out the bucks, I would ensure that everyone followed the list; no windows unless you caulk first.

But then Pella is spending more on full page ads than Obama is on the stimulus these days, so that won’t happen. And of course, Glenn Beck ran Mr. “put down the handgun and pickup a caulking gun” out of the White House, so the bucks will go to big business.

Environmental justice means the fair treatment and meaningful involvement of all people regardless of race, color, national origin, or income with respect to environmental policies.

The Faces of the Grassroots contest is an opportunity to publicly exhibit creativity with environmental justice stories, and connect with others working to raise awareness of the movement.

Videos can focus on any environmental justice activity, issue, or topic. Examples would be a music video about climate change, or a video recording a successful environmental justice project that has made a community a healthier and happier place to live.

Awards will be given to the winning submissions in each category. The videos will also be featured on EPA’s Web site and may be used as public service announcements.

Entries must be received by 11:59 p.m. EST on Thursday, April 8, 2010. EPA will announce winners in honor of the 40th anniversary of Earth Day.

Categories and prize money:

Public Service Announcements (30 or 60 seconds)
1st Place – $2,500
2nd Place – $1,500
3rd Place – $1,000
Student Winner – $500 (13-18 years old)

Informational Video (3-5 minutes)
1st Place – $2,500
2nd Place – $1,500
3rd Place – $1,000
Student Winner – $500 (13-18 years old)

More information and the promotional video: http://www.epa.gov/compliance/environmentaljustice/events/video-contest.html

protect and defend our ecosystems

Date: 16-Feb-10
Country: US
Author: Maggie Fox

WASHINGTON – The coastal fog that gives San Francisco its romantic ambiance is thinning out, a boon to drivers but a real threat to the giant redwoods there, researchers reported on Monday.

It in unclear if natural climate variations or human activity is to blame, but the result could be the loss of trees, they reported in the Proceedings of the National Academy of Sciences.

“Fog prevents water loss from redwoods in summer, and is really important for both the tree and the forest,” biologist Todd Dawson of the University of California Berkeley said in a statement.

“The coast redwood is the tallest living tree species and notably long-lived, with some individuals exceeding 2,000 years in age,” the researchers wrote in their report, available here

“If the fog is gone, we might not have the redwood forests we do now.”

Dawson and colleagues estimated the frequency of fog by looking at weather records, especially airport records dating back to 1951.

“Since 1901, the average number of hours of fog along the coast in summer has dropped from 56 percent to 42 percent, which is a loss of about three hours per day,” said Berkeley’s James Johnstone, who led the study.

The fog is caused by cool surface waters of the Pacific Ocean meeting warm air from the interior of California. It is held in place by an inversion, caused when cooler air is trapped closer to the surface.

“The data support the idea that Northern California coastal fog has decreased in connection with a decline in the coast-inland temperature gradient and weakening of the summer temperature inversion,” Johnstone said.

“As fog decreases, the mature redwoods along the coast are not likely to die outright, but there may be less recruitment of new trees,” Dawson added. “They will look elsewhere for water, high humidity and cooler temperatures.”

The coast redwood, known scientifically as Sequoia sempervirens, is naturally found in a very narrow band along the northeast Pacific coast.

The researchers found changes all the way down the coast from northernmost California to San Diego.

“Fog is clearly a dominant climatic factor on the California coast, and long-term reductions likely have and may continue to impact the water and carbon economy of redwoods and other coastal endemic species,” they concluded.

(Editing by Sandra Maler)

© Thomson Reuters 2010 All rights reserved

By Ashley Halsey III

Washington Post Staff Writer
Wednesday, January 27, 2010

http://www.washingtonpost.com/wp-dyn/content/article/2010/01/26/AR2010012603238.html?sub=AR

safety = lost time + lost income

On Tuesday, the federal government formally barred truckers and bus drivers from sending text messages while behind the wheel, putting its imprimatur on a prohibition embraced by many large trucking and transportation companies.

“We want the drivers of big rigs and buses and those who share the roads with them to be safe,” said U.S. Transportation Secretary Ray LaHood. “This is an important safety step, and we will be taking more to eliminate the threat of distracted driving.”

LaHood has made the effort to curtail driver distractions a centerpiece of his tenure as the nation’s top transportation official. Some saw his announcement as a step that might ultimately fuel a push to ban cellphone use by all drivers.

LaHood’s announcement followed a study released in July by Virginia Tech’s Transportation Institute that found that when truckers text, they are 23 times more likely to be involved in a crash or close call.

Also Tuesday, a group of senators unveiled legislation that seeks to bar all texting while driving.

“This is a giant step forward for safety on our roads, but we must do more,” Sen. Charles E. Schumer (D-N.Y.) said of LaHood’s action. “We need the administration to support our ban, which does the same thing for cars and mass transit that they are now doing for trucks and buses.”

Although both houses of Congress are considering bills restricting texting and 19 states have banned the practice, LaHood said that existing rules on truckers and bus drivers give him the authority to issue the prohibition. LaHood said drivers of commercial vehicles caught texting could be fined up to $2,750.

“It’s an important first step,” said Jonathan Adkins, a spokesman for the Governors Highway Safety Association, a coalition of state highway safety directors. “It’s will start a cultural shift away from texting and cellphone use. We’d like to see a ban on all cellphone use by drivers of commercial vehicles.”

Enforcement of LaHood’s ban is so problematic, however, that it might prove more symbolic than practical.

“The enforcement problem here is enormous,” said Russ Rader of the Insurance Institute for Highway Safety. “It’s not clear this is going to make any difference on the road in terms of crashes.”

Last year, President Obama banned federal employees from texting while driving government vehicles and from texting in their own cars if they use government-issued phones or are on official business.

With LaHood leading the effort, supported by mounting evidence of the dangers, Adkins said that an effort to ban cellphone use by all drivers could be proposed this year.

“At some point, we’ll have to address that issue,” Adkins said. “We think 2010 will be the year when we do something about distracted driving. We can’t remember a secretary ever taking the issue of highway safety so seriously.”

In announcing the ban, LaHood mentioned data compiled last year by the Federal Motor Carrier Safety Administration. The agency said that texting drivers take their eyes off the road for an average of 4.6 out of every six seconds. At 55 mph, he said, that means a texting driver travels the length of a football field, including the end zones, without looking at the road.

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