Monthly Archives: August 2012

University of Missouri and the US Geological survey study carbon nanotubes in aquatic environments

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The University of Missouri’s Aug. 22, 2012 news release (by Timothy Wall) announces the result of a carbon nanotube study in aquatic environments,

A joint study by the University of Missouri and United States Geological Survey found that they [carbon nanotubes or CNTs] can be toxic to aquatic animals. The researchers urge that care be taken to prevent the release of CNTs into the environment as the materials enter mass production.

“The great promise of carbon nanotubes must be balanced with caution and preparation,” said Baolin Deng, professor and chair of chemical engineering at the University of Missouri. “We don’t know enough about their effects on the environment and human health. The EPA and other regulatory groups need more studies like ours to provide information on the safety of CNTs.”

CNTs are microscopically thin cylinders of carbon atoms that can be hundreds of millions of times longer than they are wide, but they are not pure carbon. Nickel, chromium and other metals used in the manufacturing process can remain as impurities. Deng and his colleagues found that these metals and the CNTs themselves can reduce the growth rates or even kill some species of aquatic organisms. The four species used in the experiment were mussels (Villosa iris), small flies’ larvae (Chironomus dilutus), worms (Lumbriculus variegatus) and crustaceans (Hyalella azteca).

“One of the greatest possibilities of contamination of the environment by CNTs comes during the manufacture of composite materials,” said Hao Li, associate professor of mechanical and aerospace engineering at MU. “Good waste management and handling procedures can minimize this risk. Also, to control long-term risks, we need to understand what happens when these composite materials break down.”

I found the abstract for the team’s paper gave a good overview of how the research was conducted,

Carbon nanotubes (CNTs) are hydrophobic in nature and thus tend to accumulate in sediments if released into aquatic environments. As part of our overall effort to examine the toxicity of carbon-based nanomaterials to sediment-dwelling invertebrates, we have evaluated the toxicity of different types of CNTs in 14-d water-only exposures to an amphipod (Hyalella azteca), a midge (Chironomus dilutus), an oligochaete (Lumbriculus variegatus), and a mussel (Villosa iris) in advance of conducting whole-sediment toxicity tests with CNTs. The results of these toxicity tests conducted with CNTs added to water showed that 1.00 g/L (dry wt) of commercial sources of CNTs significantly reduced the survival or growth of the invertebrates. Toxicity was influenced by the type and source of the CNTs, by whether the materials were precleaned by acid, by whether sonication was used to disperse the materials, and by species of the test organisms. Light and electron microscope imaging of the surviving test organisms showed the presence of CNTs in the gut as well as on the outer surface of the test organisms, although no evidence was observed to show penetration of CNTs through cell membranes. The present study demonstrated that both the metals solubilized from CNTs such as nickel and the “metal-free” CNTs contributed to the toxicity.

Here’s the full citation and a link to the paper,

Toxicity of carbon nanotubes to freshwater aquatic invertebrates by Joseph N. Mwangi, Ning Wang, Christopher G. Ingersoll, Doug K. Hardesty, Eric L. Brunson, Hao Li, and Baolin Deng in Environmental Toxicology and Chemistry, Volume 31, Issue 8, pages 1823–1830, August 2012

For anyone who’s curious about what carbon nanotubes look like, here’s an image provided by the University of MIssouri,

Carbon Nanotubes Credit: Shaddack, Wikimedia Commons
Multi-walled carbon nanotubes. 3-15 walls, mean inner diameter 4nm, mean outer diameter 13-16 nm, length 1-10+ micrometers. Black clumpy powder, grains shown, partially smeared on paper. Scale in centimeters.

I could have included a larger version of the image but, given that we’re talking about the nanoscale, the smaller image seems more appropriate.

It’s the length, not the size that matters with nanofibres such as carbon nanotubes

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The Aug. 22, 2012 news item on Nanowerk by way of Feedzilla features some research at the University of Edinburgh which determined that short nanofibres do not have the same effect on lung cells as longer fibres do. From the news item, here’s a description of why this research was undertaken

Nanofibres, which can be made from a range of materials including carbon, are about 1,000 times smaller than the width of a human hair and can reach the lung cavity when inhaled.

This may lead to a cancer known as mesothelioma, which is known to be caused by breathing in asbestos fibres, which are similar to nanofibres.

I wrote about research at Brown University which explained why some fibres get stuck in lung cells in a Sept. 22, 2011 posting titled, Why asbestos and carbon nanotubes are so dangerous to cells. The short answer is: if the tip is rounded, the cell mistakes the fibre for a sphere and, in error, it attempts to absorb it. Here’s some speculation on my part about what the results might mean (from my Sept. 22, 2011 posting),

The whole thing has me wondering about long vs. short carbon nanotubes. Does this mean that short carbon nanotubes can be ingested successfully? If so, at what point does short become too long to ingest?

The University of Edinburgh Aug. 22, 2012 news release provides answer to last year’s  speculation about length,

The University study found that lung cells were not affected by short fibres that were less than five-thousandths of a millimetre long.

However, longer fibres can reach the lung cavity, where they become stuck and cause disease.

We knew that long fibres, compared with shorter fibres, could cause tumours but until now we did not know the cut-off length at which this happened. Knowing the length beyond which the tiny fibres can cause disease is important in ensuring that safe fibres are made in the future as well as helping to understand the current risk from asbestos and other fibres, [said] Ken Donaldson, Professor of Respiratory Toxicology.

Sometimes, I surprise myself. I think I’ll take a moment to bask. … Done now!

Here’s my final thought, while this research suggests short length nanofibres won’t cause mesothelioma, this doesn’t rule out  other potential problems. So, let’s celebrate this new finding and then get back to investigating nanofibres and their impact on health.

Ask and ye shall receive: a ‘communicating controversial science’ symposium

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Yesterday (Aug. 21, 2012), I expressed the hope (in my Repairing your vocal cords posting) that the American Chemical Society’s (ACS) 244th meeting would provide a session or two to counterbalance the relentless science enthusiasm (it’s like cooking where you need to add  a little salt to balance the sugar in your cake).

Providentially, the Aug. 21, 2012 (I often get the notices a day later) news release on EurekAlert announced a special symposium on controversial science being held at the Fall 2012 meeting,

The American Chemical Society (ACS), the world’s largest scientific society, is holding a special symposium today honoring Rudy M. Baum, editor-in-chief of its weekly newsmagazine, whose thought-provoking editorials and editorial leadership made Baum an icon among ACS’ more than 164,000 members.

“Rudy Baum’s editorials focused on some of the greatest challenges facing humanity,” said ACS President Bassam Z. Shakhashiri, Ph.D., who organized the symposium. It is part of the 244th ACS National Meeting & Exposition, a scientific extravaganza being held here through Thursday. The meeting features 8,600 reports on new discoveries in science and other topics, a major scientific exposition and an anticipated attendance of more than 14,000 scientists and others.

“Baum tackled inherently controversial topics ― global climate change, for instance, surging population growth, disease, violence and war and the denial of basic human rights,” added Shakhashiri, who is the William T. Evjue Distinguished Chair for the Wisconsin Idea at the University of Wisconsin-Madison. “Rudy had the courage to express his opinions forthrightly and honestly. He has challenged us all to be scientist-citizens for the benefit of Earth and its people.”

The news releases lists a number of presentations included as part of the symposium,

Abstracts

Every Day in Every Way, Chemistry Makes the World Ever Better
Richard N. Zare, Marguerite Blake Wilbur Professor in Natural Science, Stanford University

Such were not the titles or contents of Rudy Baum’s editorials in Chemical & Engineering News, although many of my friends had wished otherwise. Instead, Rudy followed a far riskier path of provoking thought and broaching controversial topics. Whether you agreed or disagreed with his points of view, they raised the level of discourse about the role of chemistry in society. Let me congratulate Rudy Baum on his many years of editorship of the flagship weekly of the American Chemical Society. He always made it clear to his readers that he was speaking for himself, not the Society, and I applaud his boldness and daring. The turtle only advances by sticking its neck out.

It’s Not Just About the Science
Eugenie Scott, Executive Director, The National Center for Science Education (NCSE)

The National Center for Science Education defends the teaching of evolution and climate change, two topics on which there is considerable scientific consensus but strong ideological pushback from the general public. How does one change the perception of the public to more closely parallel that of scientists? The normal reaction of scientists is to bemoan the quality of science education, and propose that more and better science instruction will solve the problem. However, multifactorial problems require multifactorial solutions, and the rejection by substantial proportion of the public of well-established science is certainly multifactorial. We need to go beyond science (and science education) to consider the underlying ideological sources of the rejection and how best to deal with them.

Where in the World Will Our Energy Come From?
Nate Lewis, George L. Argyros Professor of Chemistry, California Institute of Technology

Where in the world will our energy come from? What would it take for the world to get away from fossil fuels and switch over to renewable energy? It takes more than willingness to buy a Prius or to have solar panels installed on your roof. If we want to use wind, solar thermal, solar electric, biomass, hydroelectric and geothermal energy it will take a lot of planning, and willingness on the part of governments and industry. It takes R&D investment, a favorable price per unit of energy to get anyone to produce alternative energy, and plenty of resources to create those energy sources.

Lewis will discuss these and other hurdles – technical, political, and economic – that must be overcome before the widespread adoption of renewable energy technologies.

Odds Are It’s Wrong: How Misuse of Statistics Fuels Scientific Controversy
Tom Siegfried, Editor-in-Chief, Science News

Standard tests of statistical significance are widely recognized to be deeply flawed, but are nevertheless widely used in scientific studies. Far from merely a technical concern, this issue is literally a matter of life and death. Misuse of statistics generates controversies about the safety of medicines such as antidepressants that end up depriving some people of life-saving treatments. Media coverage of such issues — and scientific results in general — is confounded by the diabolical coincidence that the qualities of a scientific finding that make it newsworthy are also the qualities that render it most susceptible to being a statistical illusion.

Beware! Breaking a Paradigm can Result in Pain and Suffering
Chris Enke, Professor of Chemistry (Retired), University of New Mexico

Innovators who overturn established paradigms frequently encounter antipathy (or worse) from their scientific communities. I believe a principal cause of this reaction is confusion over which parts of scientific knowledge are facts and which are theories subject to change. We rely on verified observations and established relationships to be true and repeatable within given boundaries. However, the explanations we conceive for these relationships, even though experimentally and theoretically supported to various degrees, are neither proven nor unique. Strong attachments to widely accepted explanations influence our responses to messengers bringing news of their demise.

Toxics, Carcinogens & Mutagens …..Oh My!
Glenn Ruskin, Director, Office of Public Affairs, American Chemical Society

Generally, people fear the unknown. The general public and media often struggle with highly complex scientific issues and topics, especially those with strange names, scary properties and controversy attached to them. When confronted with the unknown, most people will “take flight” – preferring to avoid the topic or issue. In many cases, people will look to experts or organizations they think they “trust” to help explain the issue to them. People want complex and controversial topics broken down into the simplest of terms so they can make informed decisions. Unless scientists or the presenters of complex and controversial science can effectively communicate with the media and general public – disastrous outcomes can result. This presentation will look at how scientific topics can effectively be presented to foster public understanding.

Why I Love A Good Poison
Deborah Blum, Helen Firstbrook Franklin Professor of Journalism, University of Wisconsin-Madison

Journalists, they say, are drawn to controversy. Or in my case, controversial – and often hazardous – chemical compounds. Some of this has to do with the way story-telling works – a writer needs theatre to make a story compelling. But in the case of science writers, like myself, we are usually looking for the “teachable moment” that goes with that controversy, that hazard, that highly readable tale. We can use such cases to delve into everything from peer review to the realities of observational studies. And a chemistry blogger like myself can use a good poison to illustrate much about how the science works – and whether it works well.

Reporting Ethical Violations In Research
William G. Schulz, News Editor, Chemical & Engineering News

A reporter’s notebook of stories that have covered a wide range of ethical violations, including one of the worst cases of scientific fraud ever. Research ethics stories often challenge journalists to hew to their own code of ethics and avoid the pitfalls that might threaten their own journalistic reputations.

The Hockey Stick and the Climate Wars: Dispatches From The Front Lines
Michael E. Mann, Director, Earth System Science Center, The Pennsylvania State University

A central figure in the controversy over human-caused climate change has been “The Hockey Stick,” a simple, easy-to-understand graph my colleagues and I constructed to depict changes in Earth’s temperature back to 1000 AD. The graph was featured in the high-profile “Summary for Policy Makers” of the 2001 report of the Intergovernmental Panel on Climate Change (IPCC), and it quickly became an icon in the debate over human-caused (“anthropogenic”) climate change. I will tell the story behind the Hockey Stick, using it as a vehicle for exploring broader issues regarding the role of skepticism in science, the uneasy relationship between science and politics, and the dangers that arise when special economic interests and those who do their bidding attempt to skew the discourse over policy-relevant areas of science. In short, I attempt to use the Hockey Stick to cut through the fog of disinformation that has been generated by the campaign to deny the reality of climate change. It is my intent, in so doing, to reveal the very real threat to our future that lies behind it.

Covering Controversial Science for C&EN
Rudy Baum, Editor-in-Chief, Chemical & Engineering News

Science is a system for understanding nature, the only system that yields testable knowledge. Since its inception, some of the knowledge uncovered by science has been controversial because it clashed with the revealed “truth” of religious beliefs. The most prominent such clash has been the controversy over Darwinian evolution that continues today. More recently, science has been controversial when it threatened economic interests as was the case with research that established a link between smoking and cancer, CFCs and stratospheric ozone depletion, and human activities and climate disruption. I have been reporting and commenting on controversial science throughout my 32-year career at C&EN and will draw from those experiences in my talk.

Other Talks in the Symposium

Is it ‘News’ if It Happens Slowly?
George M. Whitesides, Woodford L. and Ann A. Flowers University Professor, Harvard University

Communicating Science that People May Not Be Ready to Hear
Paul T. Anastas, Director, Center for Green Chemistry and Green Engineering, Teresa and H. John Heinz III Professor in the Practice of Chemistry for the Environment, School of Forestry & Environmental Studies, Yale University

Thanks for Writing
Bassam Z. Shakhashiri, President, American Chemical Society, Professor of Chemistry, University of Wisconsin-Madison

I wish I could have been there, this looks like a very interesting lineup. Perhaps some of our Canadian science conference organizers can take some inspiration from this symposium for future meetings here in Canada.

By the way, I notice that George Whitesides is listed (third from the bottom)  as one of the symposium presenters. Whitesides was last featured here in a posting titled, Watch out Roomba! Camouflaging soft robots are on the move (Aug. 17, 2012).

Dalai Lama and a 3rd science dialogue in 2013

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Hot off my twitter feed from about 2:40 pm PDT today (Aug. 21.12): @natashamitchell (via @kristinalford) confirmed that there will be a 3rd series of science dialogues featuring the Dalai Lama on the Australian Broadcasting Corporation’s (ABC) radio service.

Mitchell provided a link to two previous Dalai Lama science dialogues hosted by ABC, the first in 2009 and the second in 2011. Excerpted from the Dialogue with the Dalai Lama webpage on the ABC radio service website (Note: I have removed links),

In recent years, the Dalai Lama has engaged in a series of dialogues with influential scientists, especially in the mind sciences. He’s interested in exploring links between Western science and what he describes as the ‘contemplative’ science of Buddhism, in an effort to better understand the human condition and promote wellbeing. …

…

[2009 dialogue series]

  • Dialogue with the Dalai Lama: Part 1 (of 3)
    Saturday 5 December 2009

From the stage of the 2009 Mind and Its Potential conference, His Holiness the Dalai Lama joins All in the Mind’s Natasha Mitchell in an extended conversation about the mind, science and much else. And, joining the dialogue over coming weeks is the founder of the field of positive psychology, Martin Seligman, leading Harvard evolutionary biologist Marc Hauser, and Buddhist scholar Alan Wallace

….

[2011 dialogue series]

Dialogue with the Dalai Lama – Part 1 [of 3] – happiness, sadness and everything in between

Saturday 25 June 2011

Is sadness important for happiness? How does compassion become a mental habit? From the Happiness and Its Causes Conference, His Holiness the Dalai Lama joins Natasha Mitchell with a panel of top scientific minds.

As for Natasha Mitchell, here’s more about her from her webpage on the ABC radio service website,

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Natasha Mitchell originally trained as an engineer, but escaped a PhD partway to pursue her real passion—radio. Her first stint behind a microphone was hosting a punk music show on Monash University’s 3MU.

She was the founding presenter and producer of ABC Radio National’s popular program All in the Mind from 2002-2012, her eclectic approach to science, psychology and culture attracting a passionate, global audience.

Natasha is currently vice president of the World Federation of Science Journalists, for which she’s served as board member since 2009. From 2009-11 she was a member of the National Health and Medical Research Council’s Human Genetics Advisory Committee.

Natasha spent a year at MIT and Harvard as a Knight Science Journalism Fellow in 2005, where she also received a Marine Biological Laboratory Journalism Fellowship.

Her work has been recognized with four Gold World Medals and the overall Grand Prize at the New York Radio Festivals, four Australian and New Zealand Mental Health Broadcast Media Awards, the Yooralla Broadcast Media Award, and the Australasian Association of Philosophy Media Professionals’ Award, among others. She was finalist for two Human Rights Awards.

Natasha Mitchell on Twitter @natashamitchell

They offer podcasts and transcripts of the previous and hopefully that will keep you satisfied until 2013.

COllaborative Network for Training in Electronic Skin Technology (CONTEST) looking for twelve researchers

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The CONTEST (COllaborative Network for Training in Electronic Skin TechnologyCOllaborative Network for Training in Electronic Skin Technology) project was launched today in Italy. According to the Aug. 21, 2012 news item on Nanowerk,

“Flexible electronics” is one of the most significant challenges in the field of future electronics. The possibility of realizing flexible and bendable electronic circuits, that can be rolled up, twisted or inserted in films around objects, would introduce a range of infinite applications in multiple fields, including healthcare, robotics and energy.

In this area, the Fondazione Bruno Kessler of Trento will coordinate the CONTEST project (COllaborative Network for Training in Electronic Skin Technology), an Initial Training Network (ITN) Marie Curie project funded by the European Commission involving European research, academic and business players. These include seven full partners (Fondazione Bruno Kessler, Italy; ST Microelectronics, Italy; Technical University Munich, Germany; Fraunhofer EMFT, Germany; University College London, UK; Imperial College London, UK; and Shadow Robotics Company, UK) and two associate partners (University of Cambridge, UK, and University of Tokyo, Japan).

The CONTEST project page at the Fondazione Bruno Kessler website offers more details,

At the heart of the CONTEST programme lies the multidisciplinary research training of young researchers. The CONTEST network will recruit twelve excellent Early-Stage Researchers (e.g. PhD students) and two Experienced Researchers (e.g. Post-Doc fellows). Information for submitting applications is available at the project’s website: http://www.contest-itn.eu/.
CONTEST activities will be coordinated by Ravinder S. Dahiya, researcher at the Bio-MEMS Unit (BIO-Micro-Electro-Mechanical-Systems) of  the Center for Materials and Microsystems (Fondazione Bruno Kessler) and by Leandro Lorenzelli, head of the Bio-MEMS Unit.
“The disruptive flexible electronics technology – says Ravinder S. Dahiya – will create change and improve the electronic market landscape and usher in a new revolution in multifunctional electronics. It will transform to an unprecedented degree our view of electronics and how we, as a society, interact with intelligent and responsive systems.”
“The investigation, in a very multidisciplinary framework, of technological approaches for thin flexible components – explains Leandro Lorenzelli – will generate new paradigms and concepts for microelectronic devices and systems with new functionalities tailored to the needs of a wide range of applications including robotics, biomedical instrumentations and smart cities.”

Here’s more about the 12 researchers they’re recruiting, excerpted from the Job Openings page on the CONTEST project website (Note: I have removed some links),

We have been awarded a large interdisciplinary project on electronic skin and applications, called CONTEST (COllaborative Network for Training in Electronic Skin Technology). We are therefore looking for 12 excellent Early-Stage Researchers (e.g. PhD students) and 2 Experienced Researchers (e.g. Post-Doc), associated to:

  • Fondazione Bruno Kessler, Trento, Italy (2 Early-Stage Researcher positions on silicon based flexible sensors (e.g. touch sensors), electronic circuits and 1 Experienced Researcher position on system integration)  …,
  • ST Microelectronics, Catania, Italy (2 Early-Stage Researcher positions on chemical/physical sensors on flexible substrates, and metal patterned substrates for integrating flexible sensing elements)…,
  • Technical University Munich, Germany (3 Early-Stage Researcher positions on organic semiconductor based electronics devices and circuits, modeling of flexible devices and sensors … , and artificial skin in humanoids…,
  • Fraunhofer EMFT, Munich, Germany (1 Early-Stage Researcher position on assembly on film substrates and foil integration as well as 1 Experienced Researcher position on reliability and ESD issues of components during flex integration) … ,
  • University College London, UK (2 Early-Stage Researcher positions on organic semiconductor based interconnects, solutions processed sensors, alternative on-skin energy schemes, patterning of e-skin and stretchable interconnects using blends of graphene in polymeric materials …
  • Imperial College London, UK (1 Early-Stage Researcher position on human sensori-motor control and robotics) …, and
  • Shadow Robotics Company, UK (1 Early-Stage Researcher position on biorobotics and mechatronics) ….

Mobility rules apply to all these positions. Researchers can be of any nationality. They are required to undertake trans-national mobility (i.e. move from one country to another) when taking up their appointment. One general rule applies to the appointment of researchers: At the time of recruitment by the host organization, researchers must not have resided or carried out their main activity (work, studies, etc.) in the country of their host organization (i.e. recruiting institute) for more than 12 months in the 3 years immediately prior to the reference date. Short stays such as holidays and/or compulsory national service are not taken into account.

Good luck to all who apply! Priority will be given to applications received by Sept. 30, 2012.

Repairing your vocal cords

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In his Kavli Foundations in Chemistry Lecture at the 244th meeting of the American Chemical Society (ACS), Robert Langer, Sc.D., discussed a material that mimics vocal cords. Langer heads a team of over 100 in laboratories at the Massachusetts Institute of Technology. From the Aug. 20, 2012 news release on EurekAlert,

The artificial vocal cord material, the first designed to restore lost flexibility in human vocal cords, results from an ongoing effort to produce artificial tissues in the lab, Langer explained. Lost flexibility in the vocal cords, due to the effects of aging or disease, is a major factor in the voice loss that affects 18 million people in the United States alone.

“The synthetic vocal cord gel has similar properties as the material found in human vocal cords and flutters in response to air pressure changes, just like the real thing,” explained Langer, who is the David H. Koch Institute Professor at MIT.

The vocal cords are two folds in the “voice box” that vibrate, or come together and away from each other very quickly to produce puffs of air that help form sounds. They function in much the same way as a reed in a saxophone. The cords consist of layers of muscle, ligament and a membrane. A layer between the ligament and the membrane is very flexible, and that flexibility and pliability is critical for speech.

But when someone, such as a teacher, a politician or a performer, overuses their voice, scar tissue develops. The same thing happens when a person gets older, accounting for the lower volume and hoarseness often apparent in older people. Cancer or having a tube inserted in the throat for medical procedures also can damage the cords. Scar tissue is stiff, and scarring leaves a person with a hoarse, breathy voice.

“About 90 percent of human voice loss is because of lost pliability,” said Steven Zeitels, M.D., F.A.C.S., Langer’s collaborator on the project. Zeitels is the Eugene B. Casey Professor at Harvard Medical School and Director of the Massachusetts General Hospital Voice Center. His patients include singers Julie Andrews of The Sound of Music fame, who lost her full vocal range after surgery done elsewhere in 1997, Steven Tyler of Aerosmith and Adele. “I recognized this need in my practice over the years, after seeing many patients with voice problems. I went to Bob Langer because I knew he could help design a material that would ultimately help patients speak and sing again. Currently, no treatments exist to restore vocal cord flexibility.”

The material had to be very flexible and be able to vibrate just like human vocal cords. After trying numerous candidates, Langer’s team settled on polyethylene glycol 30 (PEG30), which is already used in personal care creams and in medical devices and drugs approved by the U.S. Food and Drug Administration (FDA), as a starting material and created polymers based on it. The PEG30 gel can flutter at a rate of 200 times per second, which is a normal rate for a woman speaking in a conversation.

Here’s a video which shows the gel and introduces you to some of the scientists working on this project accompanied by a soundtrack of Julie Andrews singing prior to her 1997 operation,

Here’s how the gel would work based on animal testing results (from the news release),

A physician would inject the gel into a patient’s vocal cords. Patients would receive different formulations, depending on how they use their voices. The most stable version is highly “cross-linked,” which means the molecules of PEG are more tightly stitched together than in other versions. That makes the material a little bit rigid, but it would still help restore someone’s speaking voice. A singer, however, would likely receive a formulation that is more loosely stitched together, or less cross-linked, which is more flexible to allow the patient to hit high notes. The gel degrades over time, so patients would receive two to five injections per year, estimated Zeitels.

Tests in animals suggest that the material is safe, and human trials will hopefully begin in mid-2013. Some of Zeitels’ patients, such as Andrews, have formed a nonprofit organization called The Voice Health Institute, which funds Langer and Zeitels’ research on the vocal cord biomaterial.

I looked at the Voice Health Institute  (VHI) website  and found this on the About Us page (Note: I have removed some links),

The Voice Health Institute (VHI) is a federally-approved non-profit organization (501-C-3) that was established in 2003 by patients with voice loss to advance voice restoration and breathing impairment as a result of throat and larynx problems through the support of innovative research, education and outreach programs. A small group of patients from around the United States convened in New York City to share their experiences with throat and larynx cancer, vocal cord paralysis and voice loss. These patients shared their gratitude to the caregivers at the Massachusetts General Hospital while acknowledging substantial frustration with their initial management.

This highlighted the wide disparity of care offered in the United States and abroad and the generalized limited awareness of the general public about issues related to the throat, larynx and voice. Julie Andrews, the iconic singer/actress who lost her singing voice joined the VHI at its incorporation as the Honorary Chairwoman through the efforts of Dr. Steven Zeitels, her current physician and surgeon. Since then, iconic rock vocalists Steven Tyler of Aerosmith and Roger Daltrey of The Who have also provided invaluable support to the VHI to forward their mission.

The VHI has funded educational and award-wining pioneering research programs at:

  • Massachusetts General Hospital
  • Harvard Medical School
  • Massachusetts Institute of Technology
  • Boston University
  • University of South Carolina
  • American Speech-Language-Hearing Association (ASHA)
  • New England Conservatory of Music and
  • American Broncho-Esophagological Association (ABEA)

I don’t see a lot  of doctors or researchers on either the ‘working’ board which features mostly business people (Julie Andrews is the honorary chair and the six business people are all male) or the advisory board (broadcasters or singers and a better gender balance [eight members, two of whom are female]). I wonder how they decide the disbursements  if neither sets of board members have medical expertise. Presumably they convene a special committee to oversee grant submissions but who’s on the committee? In a research area that’s so highly specialized all of the players are likely to know each other. So, the people adjudicating the disbursements  this time may be applying for research funds  the next time and presenting their submissions to the last round’s applicants who are now the adjudicators.

The problem which all organizations that disburse funds face is this: if you stack committees with people who don’t have expertise in the specialty you may find they don’t understand the proposed research well enough to make informed decisions or if they are experts in the field everyone is beholden to everyone else.

Enough of this excursion into the business of funding. Langer’s work extends beyond this vocal cord research, from the news release,

Artificial vocal cords are just one artificial tissue in development in Langer’s lab. He described work on building intestinal, spinal cord, pancreatic and heart tissue in the laboratory with many different types of materials. Among them: Nanowires (which are about a tenth the diameter of a human hair) and something called “biorubber.”

“It’s hard to know when they will be ready for clinical use,” Langer said. “But In Vivo Therapeutics hopes to start clinical trials for the spinal cord tissue we’ve developed within the next year.”

Langer also recently developed a pacemaker-sized microchip that delivers just the right amount of medication at just the right time, potentially allowing thousands of patients to ditch painful needles forever. A clinical trial of the device, implanted in women with osteoporosis, has just concluded and showed that it was safe to use. The device released osteoporosis medication when it received a signal from a computer. It worked just as well as daily shots of the drug. MicroCHIPS, Inc., a company that Langer co-founded, will commercialize the remote-controlled microchip.

Another way to make medicines more effective is to make sure they go exactly to the location where they are needed; this reduces harmful side effects. Langer’s targeted nanoparticles can do just that. A clinical trial run by BIND Biosciences, another company co-founded by Langer, recently found that these nanoparticles are safe in humans. The particles have a homing molecule on them that targets them to prostate cancer cells or cancer blood vessels, and they deliver an anti-cancer medication called docetaxel. All of the materials, including the drug, are already approved by the FDA.

I expect that as the 244th meeting of ACS continues there’ll be more news about chemistry and the glorious future we can look forward to due to research. I hope they’re planning a few sessions that are less laudatory to balance things out.

Soybeans and nanoparticles

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They seem ubiquitous today but there was a time when hardly anyone living in Canada  knew much about soybeans.  There’s a good essay about soybeans and their cultivation in Canada by Erik Dorff for Statistics Canada, from Dorff’s soybean essay,

Until the mid-1970s, soybeans were restricted by climate primarily to southern Ontario. Intensive breeding programs have since opened up more widespread growing possibilities across Canada for this incredibly versatile crop: The 1.2 million hectares of soybeans reported on the Census of Agriculture in 2006 marked a near eightfold increase in area since 1976, the year the ground-breaking varieties that perform well in Canada’s shorter growing season were introduced.

Soybeans have earned their popularity, with the high-protein, high-oil beans finding use as food for human consumption, animal rations and edible oils as well as many industrial products. Moreover, soybeans, like all legumes, are able to “fix” the nitrogen the plants need from the air. This process of nitrogen fixation is a result of a symbiotic interaction between bacteria microbes that colonize the roots of the soy plant and are fed by the plant. In return, the microbes take nitrogen from the air and convert it into a form the plant can use to grow.

This means legumes require little in the way of purchased nitrogen fertilizers produced from expensive natural gas-a valuable property indeed.

Until reading Dorff’s essay, I hadn’t early soybeans had been introduced to the Canadian agricultural sector,

While soybeans arrived in Canada in the mid 1800s-with growing trials recorded in 1893 at the Ontario Agricultural College-they didn’t become a commercial oilseed crop in Canada until a crushing plant was built in southern Ontario in the 1920s, about the same time that the Department of Agriculture (now Agriculture and Agri-Food Canada) began evaluating soybean varieties suited for the region. For years, soybeans were being grown in Canada but it wasn’t until the Second World War that Statistics Canada began to collect data showing the significance of the soybean crop, with 4,400 hectares being reported in 1941. In fact, one year later the area had jumped nearly fourfold, to 17,000 hectares…

As fascinating as I find this history, this bit about soybeans and their international importance explain why research about soyboans and nanoparticles is of wide interest (from Dorff’s essay),

The soybean’s valuable characteristics have propelled it into the agricultural mix in many parts of the world. In 2004, soybeans accounted for approximately 35% of the total harvested area worldwide of annual and perennial oil crops according to the Food and Agriculture Organization of the United Nations (FAO) but only four countries accounted for nearly 90% of the production with Canada in seventh place at 1.3% (Table 2). Soymeal-the solid, high-protein material remaining after the oil has been extracted during crushing-accounts for over 60% of world vegetable and animal meal production, while soybean oil accounts for 20% of global vegetable oil production.

There’s been a recent study on the impact of nanoparticles on soybeans at the University of California at Santa Barbara (UC Santa Barbara) according to an Aug. 20, 2012 posting by Alan on the Science Business website, (h/t to Cientifica),

Researchers from University of California in Santa Barbara found manufactured nanoparticles disposed after manufacturing or customer use can end up in agricultural soil and eventually affect soybean crops. Findings of the team that includes academic, government, and corporate researchers from elsewhere in California, Texas, Iowa, New York, and Korea appear online today in the Proceedings of the National Academy of Sciences.

The research aimed to discover potential environmental implications of new industries that produce nanomaterials. Soybeans were chosen as test crops because their prominence in American agriculture — it is the second largest crop in the U.S. and the fifth largest crop worldwide — and its vulnerability to manufactured nanomaterials. The soybeans tested in this study were grown in greenhouses.

The Aug. 20, 2012 UC Santa Barbara press release has additional detail abut why the research was undertaken,

“Our society has become more environmentally aware in the last few decades, and that results in our government and scientists asking questions about the safety of new types of chemical ingredients,” said senior author Patricia Holden, a professor with the Bren School [UC Santa Barbara’s Bren School of Environmental Science & Management]. “That’s reflected by this type of research.”

Soybean was chosen for the study due to its importance as a food crop –– it is the fifth largest crop in global agricultural production and second in the U.S. –– and because it is vulnerable to MNMs [manufactured nanomaterials]. The findings showed that crop yield and quality are affected by the addition of MNMs to the soil.

The scientists studied the effects of two common nanoparticles, zinc oxide and cerium oxide, on soybeans grown in soil in greenhouses. Zinc oxide is used in cosmetics, lotions, and sunscreens. Cerium oxide is used as an ingredient in catalytic converters to minimize carbon monoxide production, and in fuel to increase fuel combustion. Cerium can enter soil through the atmosphere when fuel additives are released with diesel fuel combustion.

The zinc oxide nanoparticles may dissolve, or they may remain as a particle, or re-form as a particle, as they are processed through wastewater treatment. At the final stage of wastewater treatment there is a solid material, called biosolids, which is applied to soils in many parts of the U.S. This solid material fertilizes the soil, returning nitrogen and phosphorus that are captured during wastewater treatment. This is also a point at which zinc oxide and cerium oxide can enter the soil.

The scientists noted that the EPA requires pretreatment programs to limit direct industrial metal discharge into publicly owned wastewater treatment plants. However, the research team conveyed that “MNMs –– while measurable in the wastewater treatment plant systems –– are neither monitored nor regulated, have a high affinity for activated sludge bacteria, and thus concentrate in biosolids.”

The authors pointed out that soybean crops are farmed with equipment powered by fossil fuels, and thus MNMs can also be deposited into the soil through exhaust.

The study showed that soybean plants grown in soil that contained zinc oxide bioaccumulated zinc; they absorbed it into the stems, leaves, and beans. Food quality was affected, although it may not be harmful to humans to eat the soybeans if the zinc is in the form of ions or salts, in the plants, according to Holden.

In the case of cerium oxide, the nanoparticles did not bioaccumulate, but plant growth was stunted. Changes occurred in the root nodules, where symbiotic bacteria normally accumulate and convert atmospheric nitrogen into ammonium, which fertilizes the plant. The changes in the root nodules indicate that greater use of synthetic fertilizers might be necessary with the buildup of MNMs in the soil.

At this point, the researchers don’t know how zinc oxide nanoparticles and cerium oxide nanoparticles currently used in consumer products and elsewhere are likely to affect agricultural lands. The only certainty is that these nanoparticles are used in consumer goods and, according to Holden, they are entering agricultural soil.

The citation for the article,

Soybean susceptibility to manufactured nanomaterials with evidence for food quality and soil fertility interruption by John H. Priester, Yuan Ge, Randall E. Mielke, Allison M. Horst Shelly Cole Moritz, Katherine Espinosa, Jeff Gelb, Sharon L. Walker, Roger M. Nisbet, Youn-Joo An, Joshua P. Schimel, Reid G. Palmer, Jose A. Hernandez-Viezcas, Lijuan Zhao, Jorge L. Gardea-Torresdey, Patricia A. Holden. Published online [Proceedings of the National Academy of Sciences {PNAS}] before print August 20, 2012, doi: 10.1073/pnas.1205431109

The article is open access and available here.

 

Graphene paper batteries

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Michael Mullaney’s Aug. 20, 2012 news release for Rensselaer Polytechnic Institute (RPI) highlights work on a battery made from the worlds thinnest material. From the news release,

Engineering researchers at Rensselaer Polytechnic Institute made a sheet of paper from the world’s thinnest material, graphene, and then zapped the paper with a laser or camera flash to blemish it with countless cracks, pores, and other imperfections. The result is a graphene anode material that can be charged or discharged 10 times faster than conventional graphite anodes used in today’s lithium (Li)-ion batteries.

…

“Li-ion battery technology is magnificent, but truly hampered by its limited power density and its inability to quickly accept or discharge large amounts of energy. By using our defect-engineered graphene paper in the battery architecture, I think we can help overcome this limitation,” said Koratkar, the John A. Clark and Edward T. Crossan Professor of Engineering at Rensselaer. “We believe this discovery is ripe for commercialization, and can make a significant impact on the development of new batteries and electrical systems for electric automobiles and portable electronics applications.”

Here are some more details about the graphene paper the researchers hope will replace the less efficient elements of today’s lithium-ion batteries  (from the news release),

Koratkar’s solution [to the problem of slow charging and discharge] was to use a known technique to create a large sheet of graphene oxide paper. This paper is about the thickness of a piece of everyday printer paper, and can be made nearly any size or shape. The research team then exposed some of the graphene oxide paper to a laser, and other samples of the paper were exposed to a simple flash from a digital camera. In both instances, the heat from the laser or photoflash literally caused mini-explosions throughout the paper, as the oxygen atoms in graphene oxide were violently expelled from the structure. The aftermath of this oxygen exodus was sheets of graphene pockmarked with countless cracks, pores, voids, and other blemishes. The pressure created by the escaping oxygen also prompted the graphene paper to expand five-fold in thickness, creating large voids between the individual graphene sheets.

The researchers quickly learned this damaged graphene paper performed remarkably well as an anode for a Li-ion battery. Whereas before the lithium ions slowly traversed the full length of graphene sheets to charge or discharge, the ions now used the cracks and pores as shortcuts to move quickly into or out of the graphene—greatly increasing the battery’s overall power density. Koratkar’s team demonstrated how their experimental anode material could charge or discharge 10 times faster than conventional anodes in Li-ion batteries without incurring a significant loss in its energy density. Despite the countless microscale pores, cracks, and voids that are ubiquitous throughout the structure, the graphene paper anode is remarkably robust, and continued to perform successfully even after more than 1,000 charge/discharge cycles. The high electrical conductivity of the graphene sheets also enabled efficient electron transport in the anode, which is another necessary property for high-power applications.

Here’s a citation and link for the paper (which is behind a paywall),

Photothermally Reduced Graphene as High-Power Anodes for Lithium-Ion Batteries by Rahul Mukherjee, Abhay Varghese Thomas, Ajay Krishnamurthy, and Nikhil Koratkar in ACS Nano, Article ASAP DOI: 10.1021/nn303145j Publication Date (Web): August 11, 2012

If the researchers are successful, electric cars could become 100% battery-run.

Solid smoke; a new generation of aerogels

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The latest American Chemical Society (244th) meeting (Fall 2012, Aug. 19 – 23, 2012) includes a presentation on one of my favourite topics ‘solid smoke’ or aerogel, as it’s called more commonly.

From the Aug. 19, 2012 news item on Nanowerk (Note: I have removed a reference to a video on previous generations of aerogels that the folks at Nanowerk found and included with this news item),

A major improvement in the world’s lightest solid material and best solid insulating material, described here today, may put more of this space-age wonder into insulated clothing, refrigerators with thinner walls that hold more food, building insulation and other products.

The report, on development of a new flexible “aerogel” — stuff so light it has been called “solid smoke” — was part of the 244th National Meeting & Exposition of the American Chemical Society, the world’s largest scientific society. …

Mary Ann B. Meador, Ph.D., explained that traditional aerogels, developed decades ago and made from silica, found in beach sand, are brittle, and break and crumble easily. Scientists have improved the strength of aerogels over the years, and Meador described one of these muscled-up materials developed with colleagues at the NASA Glenn Research Center in Cleveland, Ohio.

The Aug. 19, 2012 news release from the American Chemical Society, which originated the news item, describes this new generation of aerogels’ strength and potential applications,

“The new aerogels are up to 500 times stronger than their silica counterparts,” Meador said. “A thick piece actually can support the weight of a car. And they can be produced in a thin form, a film so flexible that a wide variety of commercial and industrial uses are possible.”

Flexible aerogels, for instance, could be used in a new genre of super-insulating clothing that keeps people warm in the cold with less bulk than traditional “thermal” garments. Tents and sleeping bags would have the same advantages. Home refrigerator and freezer walls insulated with other forms of the material would shrink in thickness, increasing storage capacity. Meador said that the aerogel is 5-10 times more efficient than existing insulation, with a quarter-inch-thick sheet providing as much insulation as 3 inches of fiberglass. And there could be multiple applications in thin-but-high-efficiency insulation for buildings, pipes, water heater tanks and other devices.

NASA envisions one use in an advanced re-entry system for spacecraft returning to Earth from the International Space Station, and perhaps other missions. Re-entry vehicles need a heat shield that keeps them from burning up due to frictional heating from Earth’s atmosphere. Those shields can be bulky and heavy. So NASA is exploring use of a heat shield made from flexible aerogel that inflates like a balloon when spacecraft enter the atmosphere.

Meador said the material also could be used to insulate spacesuits. However, it likely would not be good for firefighting clothing products, which require protection beyond the 575 degrees Fahrenheit limits of the aerogel.

The scientists also offered a brief explanation of how these new aerogels are made (from the ACS news release),

Scientists produced the stronger new aerogels in two ways. One involved making changes in the innermost architecture of traditional silica aerogels. They used a polymer, a plastic-like material, to reinforce the networks of silica that extend throughout an aerogel’s structure. Another involved making aerogels from polyimide, an incredibly strong and heat-resistant polymer, or plastic-like material, and then inserting brace-like cross-links to add further strength to the structure.

My last mention of ‘solid smoke’ was in my Mar.27, 2012 posting about the 243rd meeting of the American Chemical Society held in Spring 2012.

Welcome to Something About Science; another Canadian science blog

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Lynn K, the Something About Science blogger is a (from the online profile),

…  Ph.D. candidate in biochemistry at the University of British Columbia. Biochemistry is the chemistry of life. I am interested in things that happen inside our bodies, such as what happens when you drink alcohol, what does it mean to have mutations, and how can we treat diseases like cancer and heart failure. Through this blog, I hope to intrigue your curiosity by sharing some bits of facts and stories about science in everyday life!

Lynn posts once a week on a variety of topics,

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I have a personal fondness for the July 11, 2012 posting, What is a flame? — When a house catches fire…,

“FIRE!!” In the middle of the night last week, I was woken up to find a neighbor’s house fast ablaze. The entire framework crackled and was engulfed by flames which glared bright orange against the night. Fortunately, no one was hurt, as the house was under construction, and the neighboring houses had been evacuated before they, too, caught fire.

Here are some images that recapitulate the (hopefully) once-in-a-lifetime experience.

…

But this being a science blog, my question to you is, “What is a flame?” And better yet, can you explain flames in a way everyone, including children, can understand and enjoy learning?

Alan Alda and the Center for Communicating Science at Stony Brook University, New York, have asked the same question to scientists. The Flame Challenge invited scientists to communicate science clearly to the public by explaining what flames are in a way simple and fun, yet educational. The challenge received over 800 entries, which were judged by over 6,000 children aged 11.

Lynn goes on to announce the winner, Ben Ames, a PhD student in Austria and includes the challenge-winning video animation. You can watch the video and find out where you can post a question for next year’s challenge in Lynn’s What is a flame? posting.