Antioxidants, fingerprint testing, peers

These are the latest science news links and snippets from Sciencebase:

  • Healthy antioxidants may do more harm than good – This has been my hunch for years. Now, scientists (J Agric Food Chem, ACS) are calling for more research on the possibility that some supposedly healthy plant-based antioxidants – including those that supposedly prevent cancer – may actually aggravate or even cause cancer in some people.
  • Intelligent Fingerprinting – Testing for illicit drugs often falls foul of fraud and mislabelling of urine or blood samples. New technology from Cambridge company Intelligent Fingerprinting could avoid all that simply by taking fingerprints from a suspected user and testing those instead of a urine sample for recent drug abuse. The fact that their fingerprint represents is the sample means no more mixups and no chance for fraudulent swapping of samples.
  • Interview With Jean-Claude Bradley (no relation) on the impact of open notebook science – Jean-Claude Bradley is an organic chemist at Drexel University in Philadelphia. As with most scientists, Bradley used to be very secretive. He kept his research under wraps until publication and frequently applied for patents on his work in nanotechnology and gene therapy.
  • Write for Oprah? Wrong for Me – Sounds like debunking health myths has a different meaning when it comes to the big O. Can you define "good morning" what do you mean by good and what hours constitute the pre-afternoon period?
  • Peer to Peer Mentoring – Peer-mentoring schemes have been around since ancient times, they even get a mention in Greek texts, but today they are becoming increasingly popular in academic environments as educators begin to recognise the benefits for their students of learning with a little help from their friends.
  • Why scientists are waiting for Web 3.0 – Personally, I'd be happy with web 2.1, but it seems that scientists in general are holding out their enthusiasm for web 3.0

Phantom radiation protection

Ionizing radiation exists as either subatomic particles (alpha and beta particles, and neutrons) or photons (electromagnetic waves at X-ray and gamma ray wavelengths, i.e. energies of a few electron volts). The energy from such radiation can strip electrons from atoms or molecules, thus ionizing them, but it has to have an energy above a certain threshold. An intense flood of particles or photons will not cause ionization if the individual particles do not have enough energy. The energy of a photon correlates with its frequency (it is inversely proportional to its wavelength). So, radiation of short wavelength are high-frequency ultraviolet, X-ray, and gamma rays, and are thus ionizing, whereas visible light, infra-red, microwave, and radio waves with much lower frequencies but longer wavelengths are non-ionising.

High-energy ionising radiation, which comes from natural radioactive sources, particle accelerators, and X-ray machines, is a well-established risk factor for human cancer. Exposure to radiation causes damage to living tissue, DNA damage and at low doses can cause tumour growth. At high dose, skin burns, radiation sickness and death occur.

Epidemiology based on patients treated with ionising radiation, survivors of atomic bomb blasts, and uranium workers, has revealed the risks of leukaemia, lung cancer and various tumour types associated with exposure. Equally well known, of course, is that ionising radiation has many practical uses in medicine. X-rays in imaging and other forms of ionising radiation in cancer therapy, for instance. Alpha particles, beta particles, positrons, gamma emitters, protons and X-rays are all uses to either deliberately cause ionisation to kill malignant cells or as a way of highlighting different types of tissue or diseased cells within the body.

Radiological and nuclear medicine confer a long-term risk of cancer, explains Mauro Valente of the University of Cordoba, and this risk applies not only to patients undergoing examination or treatment but also to healthcare staff and even those simply visiting a patient in hospital. Valente and his colleagues have now turned to statistical tools to help them map out the risk and to offer new boundaries to improve safety for those working in radiology and nuclear medicine.

They have developed a computational tool with an easy to use graphical user interface (GUI) based on a form of statistical analysis known as a Monte Carlo technique. The tool takes into account, the configuration of the treatment or examination room, the specific ionising radiation being used and the shape and size of the individual being irradiated.

“The first preliminary investigation confirmed that the introduced user-defined geometry was satisfactorily capable of mimicking typical treatment room,” the team says, “With the aim of representing realistic situations, all target ‘phantom’ positions were defined in such a way that at every simulated location the target phantom would mimic a person viewing the patient.”

The tool can process the necessary data and produce the corresponding graphic visualisation of potential radiation exposure for any area within a treatment room, the team adds.

“The developed system may be used for the study, characterization and quantification of exposure levels associated with specific arrangements of treatment room and facilities,” Tirao told Sciencebase. “In particularly, it is possible for each user (expert or not) to introduce the specific treatment room characteristics, facilities and patient disposition, locations where medical and technical staff are typically positioned during treatments and so on.”

In addition, the system allows the user to specify isotope emission properties, like radiation type (beta or gamma), emission spectrum and activity distribution.

“The implementation of this system may help in the assessment of exposure levels according to actual treatment room and typical exposed people locations as well as specifying radiation source distribution and emission properties,” he adds. “Authorities and departments responsible may take advantage from this information with the aim of reducing occupational exposure levels as well as minimizing the risks for occasionally exposed people, like the patient’s family.”

Research Blogging IconMauro Valente, Francisco Malano, & Germán Tirao (2010). A computational tool for evaluating the exposure risk in nuclear medicine treatments Int. J. Low Radiation, 7 (4), 333-346

Research in the past and structural correctness

These are the latest science news links and snippets from Sciencebase:

  • Scientific Research in the Past – Literally a blast from the past: This item about science in museums and finding a job in museum research was posted on way back in 2005, but was originally an “Adapt or Die” feature article for the now-defunct
  • Are you sure that structure is right? – UK chemists have developed a computer program that can work out how likely a chemical structure is to be correct, or identify the right structure from a range of possibilities.
  • Cancer Carnival #37 – Bayblab hosts the 37th edition of the cancer blog carnival.
  • Latest arXiv preprint shows you how to store entanglement – “Stuff” is the way many physicists are beginning to think of entanglement: as a resource, rather like water or energy, to be called upon when needed in the new quantum world. These physicists want to be able to create entanglement, use it and store it whenever they need to.
  • A bumper harvest of biofuel news from C&EN – Lots of clean tech, green energy, alternative fuels info from the ACS’ blog
  • Magnetic leaves – Researchers have used a fig leaf as a template to produce a complex, hierarchical structure from the magnetic and conductive material iron carbide. X-ray powder diffraction allowed them to reveal how the biological template was able to create an intricate vascular structure in a ceramic product.

Spectroscopy now!

These are the latest science news links and snippets from Sciencebase:

  • Diabetics drop the needle – A new device based on Raman spectroscopy has been developed by scientists at MIT to help patients with diabetes monitor their blood glucose levels without needing to prick their fingers to take a blood sample.
  • Pocket spotted – Researchers have identified a new class of chemicals that bind to a previously unknown allosteric pocket-a pocket outside the enzyme active site-and inhibit the enzyme FPPS. The work could have implications for new treatments of bone diseases, Paget's disease and tumour-induced bone degradation.
  • Infrared watermarks – Water molecules continuously form short-lived clusters that can be rapidly protonated in the liquid state. Now, computer simulations revealed how protonated water clusters interact with nearby messenger molecules, which are required to measure their geometrical structures and the chemical properties by IR spectroscopy.
  • Dollar signs and the brain – Functional magnetic resonance imaging has revealed a region of the brain about two inches above the left eyebrow that lights up whenever a person anticipating a reward for a task performed successfully is shown a dollar sign. The response is linked to dopamine release in response to pre-determined cues of which a symbol for money is one.
  • Top ten writing tips for scientists – If you’re more at home with numbers than words, writing can be a difficult prospect. Learning a few simple techniques can make all the difference, according to Sciencebase guest contributor Rob Ashton.
  • Dental care without toothpaste – Hmmm…they're apparently still testing this toothpaste-free toothbrush, but the blurb says: "The Soladey-J3DX toothbrush is powered by natural sunlight and brings teeth brushing to a new technological plateau. It does away with toothpaste because the embedded solar panel in the centre of the toothbrush can transmit electrons which react with the acid in the saliva to fight plague and bacteria." Like I said. Hmmm…