Monitor-Merrimac Memorial Bridge-Tunnel

photo of Hampton Roads Virginia Bridge-Tunnel

Now that is some cool engineering: a bridge that becomes a tunnel. The Monitor-Merrimac Memorial Bridge-Tunnel is a 4.6 miles (7.4 km) crossing for Interstate 664 in Hampton Roads, Virginia, USA. It is a four-lane bridge-tunnel composed of bridges, trestles, man-made islands, and tunnels under a portion of the Hampton Roads harbor where the James, Nansemond, and Elizabeth Rivers come together in the southeastern portion of Virginia.

If you like this post, please look at our other popular posts, and consider adding our blog feed to your blog reader. Posts such as: Bacteriophages: The Most Common Life-Like Form on Earth, Robot Finds Lost Shoppers and Provides Directions and The Engineer That Made Your Cat a Photographer

It was completed in 1992, after 7 years of construction, at a cost $400 million, and it includes a four-lane tunnel that is 4,800 feet (1,463 m) long, two man-made portal islands, and 3.2 miles (5.1 km) of twin trestle.

Photos by Virginia Department of Transportation. Details from wikipedia. Google satellite view of the bridge-tunnel.

Waste from Gut Bacteria Helps Host Control Weight

A single molecule in the intestinal wall, activated by the waste products from gut bacteria, plays a large role in controlling whether the host animals are lean or fatty, a research team, including scientists from UT Southwestern Medical Center, has found in a mouse study.

When activated, the molecule slows the movement of food through the intestine, allowing the animal to absorb more nutrients and thus gain weight. Without this signal, the animals weigh less.

The study shows that the host can use bacterial byproducts not only as a source of nutrients, but also as chemical signals to regulate body functions. It also points the way to a potential method of controlling weight, the researchers said.

“It’s quite possible that blocking this receptor molecule in the intestine might fight a certain kind of obesity by blocking absorption of energy from the gut,” said Dr. Masashi Yanagisawa, professor of molecular genetics at UT Southwestern and a senior co-author of the study, Proceedings of the National Academy of Sciences, open access: Effects of the gut microbiota on host adiposity are modulated by the short-chain fatty-acid binding G protein-coupled receptor, Gpr41.

Humans, like other animals, have a large and varied population of beneficial bacteria that live in the intestines. The bacteria break up large molecules that the host cannot digest. The host in turn absorbs many of the resulting small molecules for energy and nutrients.

In the Big Fat Lie I mentioned some related ideas:

It also makes perfect sense that our bodies evolved to store energy for worse times (and some of us have bodies better at doing that). Now we are in a new environment where (at least for many people alive today) finding enough calories is not going to be a problem so it would be nice if we could tell our bodies to get less efficient at storing fat

This research seems to be looking for a similar way to attack the obesity epidemic: reduce the efficiency of our bodies converting potential energy in the food we eat to energy we use or store. If we can make that part of the solution that will be nice. So far the reduction in our activity and increase in food intake have not been getting good results. And efforts to increase (from our current low levels) activity and reduce food intake have not been very effective.
Continue reading →

Plants can Signal Microbial Friends for Help

When under attack, plants can signal microbial friends for help

Researchers at the University of Delaware have discovered that when the leaf of a plant is under attack by a pathogen, it can send out an S.O.S. to the roots for help, and the roots will respond by secreting an acid that brings beneficial bacteria to the rescue.
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In a series of laboratory experiments, the scientists infected the leaves of the small flowering plant Arabidopsis thaliana with a pathogenic bacterium, Pseudomonas syringae. Within a few days, the leaves of the infected plants began yellowing and showing other symptoms of disease.

However, the infected plants whose roots had been inoculated with the beneficial microbe Bacillus subtilis were perfectly healthy. Farmers often add B. subtilis to the soil to boost plant immunity. It forms a protective biofilm around plant roots and also has antimicrobial properties, according to Bais.

Using molecular biological tools, the scientists detected the transmission of a long-distance signal, a “call for help,” from the leaves to the roots in the plants that had Bacillus in the soil. The roots responded by secreting a carbon-rich chemical–malic acid.

All plants biosynthesize malic acid, Bais explains, but only under specific conditions and for a specific purpose–in this case, the chemical was actively secreted to attract Bacillus. Magnified images of the roots and leaves showed the ratcheted-up defense response provided by the beneficial microorganisms.
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“Plants can’t move from where they are, so the only way they can accrue good neighbors is through chemistry,” Bais notes.

Huge Tomb Uncovered in Rome

‘Gladiator’ tomb is found in Rome

The tomb of a general thought to have been an inspiration for the main character in the Oscar-winning film Gladiator has been unearthed in Rome.
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The tomb was discovered along the northbound Via Flaminia where construction work has been taking place. Many marble columns, inscriptions and decorations have been beautifully preserved thanks to the mud caused by a centuries-old flood of the River Tiber. It is “the most important ancient Roman monument to come to light for 20 or 30 years”, said senior archaeologist Daniela Rossi.

Workers renovating a rugby stadium have uncovered a vast complex of tombs that mimic the houses, blocks and streets of a real city… Meanwhile, archaeologists restoring imperial residences in the heart of ancient Rome are also reported to have found what they believe to be the underground passageway where the Emperor Caligula was murdered by his guards…

Problems Programming Math

Arithmetic Is Hard – To Get Right by Mark Sofroniou

I’ve been working on arithmetic in Mathematica for more than 12 years. You might think that’s silly; after all, how hard can arithmetic be?
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The standard “schoolbook” algorithms are pretty easy. But they’re inefficient and often unnecessarily inaccurate. So people like me have done a huge amount of work to find algorithms that are more efficient and accurate. And the problem is that these algorithms are inevitably more complicated, and one has to be very careful to avoid insidious bugs.

Take multiplying integers, for example. The standard “schoolbook” long-multiplication algorithm uses n^2 multiplications to multiply two n-digit numbers. But many of these multiplications are actually redundant, and we now know clever algorithms that take n^1.58, n log n, or even fewer multiplications for large n. So this means that if one wants to do a million-digit multiplication, Mathematica can do it in a fraction of a second using these algorithms–while it would take at least a few minutes using standard long multiplication.
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It’s not easy to get reliable numerical computation, and it’s not something one can “bolt on” after the fact. It’s something one has to build in from the beginning, as we’ve done in Mathematica for nearly 20 years.

Friday Robot Fun

Buy your own Tomy i-SOBOT Robot ($180)

High-School Social Skills Predict Better Earnings than Test Scores

High-School Social Skills Predict Better Earnings than Test Scores

Ten years after graduation, high-school students who had been rated as conscientious and cooperative by their teachers were earning more than classmates who had similar test scores but fewer social skills, said a new University of Illinois study.

The study’s findings challenge the idea that racial, ethnic, and socioeconomic gaps in educational attainment and earnings can be narrowed solely by emphasizing cognitive skills, said Christy Lleras, a University of Illinois assistant professor of human and community development.

“It’s important to note that good schools do more than teach reading, writing, and math. They socialize students and provide the kinds of learning opportunities that help them to become good citizens and to be successful in the labor market,” she said.

“Unless we address the differences in school climates and curriculum that foster good work habits and other social skills, we’re doing a huge disservice to low-income kids who may be entering the labor market right after high school, especially in our increasingly service-oriented economy,” Lleras added.

The University of Illinois study analyzed data from the National Educational Longitudinal Study, which followed a diverse group of 11,000 tenth graders for 10 years, tracking not only their scores on standard achievement tests but teacher appraisals of such qualities as the students’ work habits, their ability to relate well to peers, and their participation in extracurricular activities, a proxy for the ability to interact well with both students and adults.

The teachers’ assessments were then compared with the students’ self-reported educational attainments and earnings 10 years after high-school graduation. Even after controlling for students’ achievement test scores, family socioeconomic status, and educational attainment, Lleras found that such social skills as conscientiousness, cooperativeness, and motivation were as important as test scores for success in the workplace.

Reducing Poverty

photo of Rita Bashnet

Today is blog action day, which this year is focused on poverty. We have highlighted various uses of appropriate technology, many of which help those in poverty improve their lives. Such as: Water Pump Merry-go-Round and Smokeless Stove Uses 80% Less Fuel.

I am also very interested in using micro loans to help entrepreneur improve their lives – I have written about Kiva before. Kiva fellows are funded by Kiva (fellows are unpaid) to go to spend time in the countries Kiva facilitates loans for working with the local partners. This post is about Rita Bashnet (in photo) an entrepreneur from Nepal:

Field visits are by far the best part about being a Kiva Fellow. You’re given the opportunity to hop on a motorbike, hike up a village trail, and actually see the impact of a Kiva loan firsthand.
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Five years ago, Ms. Rita took her first loan of NRs. 10,000 (USD $150) and purchased some extra seed and fertilizer in the hopes of expanding her small vegetable patch. With the profits from this initial investment and a second loan from Patan Business and Professional Women (they offer a graduated loan program), she then purchased her first dairy cow.
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After hearing about a program that subsidized the installation of methane gas storage tanks, Ms. Rita took another loan and applied for the program. With this new system, she is now able to capture the valuable gas released from her cow’s waste in a simple controlled-release storage tank. Today she no longer purchases gas from the city and can even sell some during times of shortage.
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Ms. Rita exemplifies the potential of microfinance. A combination of access to capital and strategic investment has allowed her and her family to drastically improve their economic situation in a short five years.

Great story, and exactly my hope for using capitalism to improve the standard of living for people around the globe.

If you haven’t loaned money through Kiva, please consider it now. If you do (or already have a Kiva page), send me your Kiva lender link and I will add it to Curious Cat Kivans. I would love to add more of our readers to that page.

Mentors Prepare Women for Construction Career

photo of Heather Cavitt

Mentors prepare women for construction career

Now Cavitt and other women in the construction school, a part of ASU’s Ira A. Fulton School of Engineering, can give themselves another advantage: Learning from pioneering women who have already risen to leadership positions in the business.

The school recently established its Advancing Women in Construction program, a key part of which is a mentorship project. More than 70 women – and several men – in the construction industry in the greater Phoenix area have signed on to mentor female students and provide them an inside look at life in the industry.
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plan to increase female enrollment from less than 15 percent of total enrollment to 30 percent – or about 200 female students – within five years.

Cavitt says her favorite things about the school’s construction management program are the opportunities to learn beyond the classroom, such as internships and building-project competitions between construction students at other universities. She expects the mentoring program to add significantly to the value of her college education. “I’m excited to learn about the real-world business of construction from women who have been successful at it for many years,” she says.

photo: School of Construction student Heather Cavitt (front) will gain from the experience of Crystal Slawson (center), president of Phoenix Pipelines and Natalie Palmer, the company’s project coordinator, through the school’s Advancing Women in Construction mentorship program.

Silk E.coli Sensors

“Edible Optics” Could Make Food Safer

Scientists at Tufts University’s School of Engineering have demonstrated for the first time that it is possible to design such “living” optical elements that could enable an entirely new class of sensors. These sensors would combine sophisticated nanoscale optics with biological readout functions, be biocompatible and biodegradable, and be manufactured and stored at room temperatures without use of toxic chemicals. The Tufts team used fibers from silkworms to develop the platform devices.
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The possibility of integrating optical readout and biological function in a single biocompatible device unconstrained by these limitations is tantalizing. Silk optics has captured the interest of the Defense Department, which has funded and been instrumental in enabling rapid progress on the topic. The Defense Advanced Research Projects Agency (DARPA) awarded Tufts a research contract in 2007 and is funding Tufts and others on groundbreaking projects that could someday result in biodegradable optical sensing communications technology.
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To form the devices, Tufts scientists boiled cocoons of the Bombyx mori silkworm in a water solution and extracted the glue-like sericin proteins. The purified silk protein solution was ultimately poured onto negative molds of ruled and holographic diffraction gratings with spacing as fine as 3600 grooves/mm.
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The Tufts team embedded three very different biological agents in the silk solution: a protein (hemoglobin), an enzyme (horseradish peroxidase) and an organic pH indicator (phenol red). In the hardened silk optical element, all three agents maintained their activity for long periods when simply stored on a shelf. “We have optical devices embedded with enzymes that are still active after almost a year of storage at room temperature.