Want bigger plants? Get to the root of the matter

 Weird
Jun 302012
 


From their 3-D root scans, the researchers observed that quickly extend their roots to the pot’s walls. It is likely that the plants use their roots to ‘sense’ the size of the pot, although the details of how the roots relay the message about the pot’s size remain the plants’ secret.

They also looked at 65 independent studies across a wide range of species including tomato, , , cactus, , and , and found that all species reach larger sizes when grown in a bigger pot. On average, doubling pot size allowed plants to grow 43% larger.


Want bigger plants? Get to the root of the matter
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This image shows the roots of a barley plant in a cylindrical pot imaged by MRI 44 days after sowing. Blue roots are in the outer 50 percent of the pot volume, yellow roots are in the inner 50 percent of the pot volume, the stem of the barley plant is in red. Credit: Jonas Bühler

Dr Hendrik Poorter (Forschungszentrum Jülich, Germany) who led the study, said: “There has been commercial interest in seeing how small pots can be, but our aim was to see how big a pot needs to be to avoid affecting plant experiments.”


Want bigger plants? Get to the root of the matter
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This image shows the roots of a sugar beet growing in a cylindrical pot, imaged by MRI 44 days after sowing. Roots in blue grew in the outer 50 percent volume of the pot, roots in yellow grew in the inner 50 percent pot volume, and the storage organ of the sugar beet is in red. Credit: Jonas Bühler

The work is relevant for gardeners too. Poorter added, “After this study, I immediately changed the pot size for all the plants I had in my house.”

To understand the pot size effect, the scientists looked at various aspects of the plants’ growth. They found that the plants in smaller pots grew more slowly because of a decreased rate of photosynthesis. But, looking for causes for the decrease, the scientists ruled out limitations in water and nutrients and did not find any differences in the thickness of the leaves for plants in smaller pots. It is therefore unlikely that the plants use water and nutrient levels to sense the pot size, supporting the possibility that sensing happens another way, such as by the roots.

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Article source: http://phys.org/news260281233.html

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Falling lizards use tail for mid-air twist, inspiring lizard-like ‘RightingBot’

 Weird
Jun 302012
 


This work, carried out by Ardian Jusufi, Robert Full and colleagues at the University of California, Berkeley, explains how large-tailed animals can turn themselves right side up while falling through the air. It could also help engineers to design air- or land-based robots with better stability.

“It is not immediately obvious which mechanism an animal will use to accomplish aerial righting and recover from falling in an upside-down posture. Depending on body size, and mass distribution there are multiple strategies for animals to execute this behavior,” said Ardian Jusufi, lead author of the study.

in their natural environment encounter various situations where they could fall. For instance, they could fall while fighting over territory, seeking food, or even mating. To avoid injuries, they must have a way to turn themselves during a fall to land safely on their feet.


Falling lizards use tail for mid-air twist, inspiring lizard-like 'RightingBot'
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To turn right-side up when falling, lizards swing their large tails one way to rotate their body the other. Credit: Ardian Jusufi

For over a century, people have been studying if and how cats and other mammals right themselves when they fall. Other animals like lizards, which have different body plans and probably use different strategies, have been largely unexplored.

The researchers used high-speed videography to dissect the motion of two common lizards – the flat-tailed house gecko and green anole – as they fall, starting upside down. Watching as the lizards righted themselves in mid-air before alighting on extended legs, the researchers discovered that both lizards swing their tails in one direction, causing their bodies to turn in the other.

The team also compared the righting movement of the two lizards, which have similar body sizes but different tail lengths and inertial properties. The gecko, with its shorter tail, has to swing its tail further to the side to right itself, making a larger angle relative to its body. By contrast, relatively smaller movements of the anole tail, which is twice as long, are enough to reorient its body.

“A comparative approach provides useful insights in the study of aerial righting responses and could be beneficial to the design of robots that navigate complex environments,” said Ardian Jusufi.

For the study, Jusufi and his colleagues developed a three-dimensional mathematical model to test their understanding of the lizards’ righting movement.

To further test the mathematical model’s predictions the team then built a simple . ‘RightingBot’ consists of just two parts: a body joined to a tail. Despite its simple design, RightingBot rights itself in mid-air with a swing of its tail just like the lizards that inspired it, showing how useful a can be for that purpose.

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Article source: http://phys.org/news260281431.html

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A Thought About Chief Justice Roberts

 Legal
Jun 302012
 

When Roberts was nominated to the Supreme Court, one especially remarkable biographical detail came to light: every one of his friends interviewed by the media, conservative, liberal, and otherwise, swore they had never heard him express any opinion in private conservation on any controversial Supreme Court cases. How could it be that a top Washington lawyer, a veteran of the Reagan Administration who eagerly expressed rather strong political and legal views while serving in that administration, had avoided talking about any of great constitutional and other cases of the day?

Well, it suggests that he intentionally avoided discussing any of the cases, lest he say something that could get him in trouble in judicial nomination hearings in the future, or otherwise somehow interfere with his political career. This suggests a few relevant things about Roberts:

(1) He is extremely self-disciplined.

(2) He is extremely risk-averse. Besides avoiding discussion of any Supreme Court cases with his many high-powered DC acquaintances, as disclosed during his nomination battle, while he participated in Federalist Society events he never became a member. The most likely reason that a young conservative DC lawyer would avoid doing so is that he thought it could be a negative in future confirmation hearings. This risk-aversion seems have been on display in his unwillingness to provide a fifth vote to invalidate Obamacare.

(3) Consistent with the theory that his opinion is part of a long-term strategy, Roberts exhibits both farsightedness and a confidence in his own role in history. How many thirty-something DC lawyers, no matter how strong their credentials, censor their private conservations because they think they may be nominated to the Supreme Court someday? Many individuals, including John Yoo in today’s WSJ, share my skepticism that Roberts is pursuing what seems to be a tenuous and unrealistic long-term strategy. But perhaps it wouldn’t be the first time.

For those disappointed with Roberts’ opinion, it may suggest a rule for future nominations: it’s better to nominate the type of individual who is forthright in his views, and if asked about his participation in the Federalist Society, would defend the organization and his membership therein (which really tells you nothing more than that the individual in question is not on the “left”). Whether such a person is confirmable nowadays is another question.

Article source: http://feedproxy.google.com/~r/volokh/mainfeed/~3/RAt_QDHpXM4/

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From Marty Lederman’s Mouth to God’s Ears

Georgetown lawprof Martin Lederman had this to say about the undue coercion challenge to the Medicaid expansion back in March: It is one thing to suggest—as litigants in many past Spending Clause cases have—that Congress may not use the lure of its valuable funding to “coerce” the States to spend their own funds outside the federal program, or regulate their own citizens, in a way that Congress could not insist upon directly. The Court has always rejected such arguments, and [Read More]

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So, Speaking of Soccer . . .

OK, nobody actually was speaking of soccer. . . . But I’ve been away from home (and the VC) for a while (six weeks in Italy), and after a 20-hour transatlantic ordeal I come home in the midst of this firestorm about the healthcare decision (about which I have, at the moment, nothing intelligent to say).  Ordinarily, I’d hang back for a few days to gather my thoughts before returning to the blog, but important events on other fronts dictate otherwise. [Read More]

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Splitsville

And then there’s Tom Cruise and Katie Holmes, neither of whom are on my radar, who are getting divorced. It’s Katie’s decision, and she’s seeking sole custody. That speaks volumes so what’s the deal? Looks like Scientology may be the factor ripping them apart. Their daughter, Suri, is about to reach an age where Scientology expects her cooperation. How so? Suri is at the age when children typically begin participating in a core Scientology practice called auditing a version of [Read More]

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2011 Wiretap Stats Released

These stats don’t even include most forms of electronic spying for which the Government doesn’t need a warrant based on probable cause — like pen registers/trap and trace devices or obtaining toll records, subscriber information, e-mail and social media account information. Nor do the stats include the rampant use of cell phone tracking. The Justice Department is fighting legislative proposals to require warrants for cell phone tracking. It says it would “cripple law enforcement.” More here. Here’s the ACLU‘s report [Read More]

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One step closer to robotic refueling demonstrations on space station

A joint effort between NASA and the Canadian Space Agency (CSA), RRM is an external station experiment designed to demonstrate the technologies, tools, and techniques needed to robotically repair and refuel satellites in orbit, especially those not built with servicing in mind. RRM results and lessons learned are reducing the risks associated with satellite servicing and bolstering the foundation for future robotic servicing missions. “Now that these tasks are complete, our eyes are now set on the RRM refueling demonstration [Read More]

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