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Small chemical barbs (cones) slow the release of anti-cancer antibodies (blue) from this functionalized mesoporous silica (orange). Artist's rendering; not to scale. Credit: PNNL, Univ. of Washington

Like bees and their honeycomb, a team of PNNL and University of Washington scientists have figured out a way to pack tumor killing antibodies into the cavities of porous silica particles, hopefully creating a superior transport system for anti-cancer agents.

They have demonstrated that they can embed antibodies into the structure of chemically modified silica particles that have already been shown to be biocompatible. “The silica’s mesoporous nature provides honeycomb-like structures that can pack lots of individual drug molecules,” says PNNL material scientist Jun Liu. “We’ve been exploring the material for our energy and environmental problems, but it seemed like a natural fit for drug delivery.”

The general idea is to spare noncancerous tissue from exposure to antibodies and direct an intense dose at the actual tumor site. According to results published in the Journal of the American Chemical Society, the particles can help anti-cancer antibodies prevent tumor growth and prolong the lives of mice.

The mesoporous silica particles have diameters of about six to 12 micrometers and pores of about 30 nanometers in diameter. The group was able to improve the containment of antibodies by attaching small chemical “barbs” of amine, carboxylic acid or sulfonic acid groups to the interior portion of the silica material’s pores. These barbs didn’t fully prevent the antibodies from leaking out, but the researchers discovered they could fine tune the leakage rate by tinkering with the the concentration and choice of chemical composition of the barbs.

In test on mice, the particles were injected directly into tumors. The results were significantly slowed tumor growth, compared with control groups, and prolonged life.

“We are very excited by our preliminary results,” says PNNL biochemist Chenghong Lei. “We plan to do some additional, larger studies with animals. We hope the results hold up well enough to take it to clinical trials somewhere down the road.”

The team is hopeful that the delivery system will prove effective with cancers that form solid tumors such as breast cancer.

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Credit: Boston.com

The AP is reporting that there have been numerous problems and failures related to the use of cement in sealing oil wells in the Gulf of Mexico. One current theory is the the Deepwater Horizon spill also may have been caused by problems with cement.

And, apparently federal regulators never set standards about what type of cement(s) should be used:

The drillers are urged to simply follow guidelines of the American Petroleum Institute, an industry trade group.

Far more stringent federal and state standards and controls exist on cement work for roads, bridges and buildings.

[. . . ]

An AP review of federal accident and incident reports on offshore wells shows that the cementing process has been implicated at least 34 times since 1978. Many of the reports, available from the U.S. Minerals Management Service that regulates offshore wells, identify the cause simply as “poor cement job.”

[ . . . ]

Reports by MMS, a branch of the Interior Department, also provide evidence of the role bad cement work has played in accidents. One study named cementing as a factor in 18 of 39 well blowouts at Gulf rigs from 1992 to 2006. Another attributed five of nine out-of-control wells in the year 2000 to cementing problems.

[ . . . ]

Halliburton, which had the Deepwater Horizon job, mixes in nitrogen to make its slurry more elastic. The nitrogen also helps create a lightweight cement that resembles a gray foamy mousse and bonds better to the casing.

But the recipe also depends on the job, because cement must respond to varying pressures and temperatures. Cement contractors work closely with oil and gas companies on the formulas for individual wells. The oil and gas companies have the final say on what is used.

ACerS Cements Division is partnering for an upcoming meeting July 11-13 with the Center for Advanced Cement-Based Materials. As one of the big cements research centers in the U.S., it’s good to see ACBM and other colleagues weigh in on this:

In the wake of the accident, some experts support mandatory uniform cement standards for underwater wells. “When you change the composition, it should meet a certain standard. Such standards exist for the building construction industry,” said Surendra Shah, Northwestern University engineering professor and director of the Center for Advanced Cement-Based Materials at Evanston, Ill.

[ . . . ]

Many construction projects use concrete hardened with sand and gravel aggregate, but cement is the glue that holds it together. On federal projects, “just about everything is regulated, from the thickness of the concrete, to the strength of the concrete, to the type of aggregate that’s used,” said Brian Turmail, spokesman for the Associated General Contractors of America.

I suspect this topic may be hashed over at the ACerS Cements Division/ACBM meeting.

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S&T student Emily Pasch working in Erquis Sud last year. (Credit: Missouri S&T.)

Students from Missouri University of Science and Technology will bring sustainable, clean water to portions of rural Bolivia this summer.

Students with the university’s Engineers Without Borders chapter are making the trip this summer. S&T’s EWB chapter began working with the community of Erquis Sud in 2008.

Team leader Emily Pasch, a senior in mechanical engineering from Lake Zurich, Ill., says S&T students have designed a water distribution system for the subdivision. The system connects a well to a storage tank and uses PVC pipes to distribute water to houses in the subdivision. The planned well will be dug deep enough to draw clean water that will require little or no treatment. The team will also provide funds to bring electricity to the community to power a submersible pump for the system so that water could potentially be pumped automatically up to the storage tank.

“The project is anticipated to have drastic effects on the health of the community members, particularly infants,” Pasch explains.

In Tacachia, designed a new water distribution system that includes two hydraulic ram pumps, two settling tanks, two 2,500-gallon storage tanks, and in-home biosand filters.

“These pumps use the flow rate of the Rio Palca river - not electricity - to divert water from the river up a mountainside where settling tanks will be located,” says team leader Matthew Schultz of Ellisville, Mo., a senior in architectural and civil engineering. “This will lower the suspended solids in the water before it’s sent to the storage tanks. From there, water can be distributed throughout a PVC pipe system to each of the homes.”

Inside each home, a biosand filter will then make the water drinkable.

Last year, S&T students introduced the concept of biosand filtration to the community by installing 10 precast concrete filters. The team also constructed one of the needed ferrocement storage tanks. Ferrocement structures are typically strong and inexpensive to build, and made from a wire-reinforced mixture of sand, water and cement.

This year the students plan to build the two settling tanks and 30 biosand filters, using 160-liter plastic barrels for the bodies of the filters. S&T student will also continue to assess the feasibility of constructing an 800-foot-long pedestrian footbridge across the river to provide access to health and educational facilities on the opposing riverbed during the rainy season.

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Clarke with Champion Supersuit: Credit Clarke and Hanesbrand

Following up on the post from last week about Hanesbrands/Element 21’s Champion aerogel jacket that was used in Jamie Clarke’s successful ascent of Mt. Everest, an AP story indicates that the superinsulating Supersuit jacket may be in stores soon, and that Aspen Aerogel – the source of the insulation in the jacket – business is growing well enough that it plans to double the size of one of its facilities.

From the AP:

Champion parent Hanesbrands and Element 21, a Toronto company that licensed the aerogel technology, have spent two years and $2 million to solve those problems. If they succeed, they might have a competitor to insulators such as Thinsulate and Primaloft.

[. . . ]

The company wants to push aerogel into even more mainstream applications, including mass-market Champion gear set to be sold at Target and other stores sometime next year. Hanes spokesman Matt Hall said any Champion item developed containing aerogel would be “significantly under $100.”

The story goes on to note that Aspen has outgrown a fairly new $30 million, 150,000 square foot plant in East Providence, R.I.:

Aspen, based in Northborough, Mass., lowered costs by opening up to new industrial markets, making its manufacturing more efficient by improving chemistry and lowering costs for its raw material. It has also expanded manufacturing, opening a plant in Rhode Island in 2008. It now plans to double the plant’s size.

 

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RechargeIT converted plug-in hybrids at Google's Mountain View campus. The garage has recharging facilities powered by solar panels. Credit: Marcin Wichary, Flickr

A new National Research Council report starts to get at the real costs of energy versus what everyone pays at the gas pump or to their utility company.

Damage to human health from burning coal for electricity, for example, totaled about $62 billion in 2005. Driving motor vehicles produced $56 billion in health and other damages. And using natural gas to heat our homes, workplaces, and factories resulted in about $1.4 billion in harm. All told, the damages from U.S. energy use that the study committee was able to quantify added up to an estimated $120 billion in 2005. Not included in those dollar figures was harm from climate change, which the committee found impossible to estimate as a single number because of the wide-ranging possibilities for the damages. Instead, it estimated ranges for the climate-related damages; for example, the cost of those that result from burning coal to generate electricity range from about 0.1 cents to 10 cents per kilowatt-hour.

The report also has some other findings that are, to me at least, new:

• Almost half the damages to human health and other nonclimate-related harms caused by coal-fired power plants could be traced to a just 10% of generating plants.
• Electric vehicles and plug-in hybrids, by themselves, have greater damages than many other vehicle technologies because of hidden costs in the electricity used to power them and to create the batteries and electric motors.
  
• Corn-based ethanol also had higher damages than many other types of vehicle fuel because of the energy used to produce the corn and convert it to fuel.

The report suggests that, “the most efficient policies to tackle hidden costs are likely to be targeted at the damages themselves, not the energy use - for example, by taxing the sulfur dioxide emissions from power plants rather than the electricity generated by them.”

In a separate but related new report about PHEVs, the NRC also says the new generation of hybrid vehicles will have little impact on oil dependency or CO₂ emissions “until tens of millions of them are on the road, which will take decades.”

The report pins much of the blame for relatively low levels of anticipated sales on the higher sticker price for PHEV vehicles. But this is where I think the NRC’s conclusions get dicey.

Coupled with the first report above, it seems that government policy conceivably could shift how the hidden costs are paid and transfers those payments into subsidies that offset the purchase prices. In other words, we can either accept the hidden costs and continue to indirectly subsidize by having everyone pay through higher health care costs, environmental remediation, etc., and change nothing, or we tax the emissions and use policies to incentivize more efficient practices (not just PHEVs but also trains, public transit and zoning) through direct subsidies. More PHEVs, even if they turn out to be a transitional technology, means better manufacturing processes and less expensive per-vehicle costs.

Policies could also reward the use of solar-powered recharge stations, such as the one featured in the picture above.

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