Daily Archives: 18 October 2012

More scientists are retracting papers for misconduct

The rate of retractions of scientific papers is rising, being up by a factor of 10 since the 1970s. But a new study shows that this is due more to fraud and misconduct, rather than simple mistakes.

The researchers from Princeton University looked at all 2,047 articles retracted in the field of biomedical and life-science research, as indexed on 3 May 2012 by the US National Library of Medicine’s PubMed service (Fang FC, Steen RG & Casadevall A 2012, “Misconduct accounts for the majority of retracted scientific publications”, Proceedings of the National Academy of Sciences, vol. 109, no. 42, pp. 17028-17033, doi: 10.1073/pnas.1212247109).

They found that only 21.3% of retractions could be attributed to error, with 67.4% being due to misconduct.

‘Misconduct’ here includes fraud or suspected fraud (43.4%), as well as duplicate publication (14.2%) and plagiarism (9.8%).

The rise in retractions has often been put down to pressure to publish leading to mistakes getting through, but the high incidence of fraud suggests that it’s more than mere carelessness.

What’s really concerning is the high rate of citations of these papers, even after they’ve been retracted. Once something is published, there’s no realistic way to control how others use it.

In the long term, these effects may even out. Assuming other researchers follow the scientific method properly, even if they start from a flawed citation their own, rigorous research will correct it. The scientific process will clean things up eventually.

But in the short term, inaccurate research can cause serious problems. An example is Dr Andrew Wakefield’s 1998 study published in The Lancet, which claimed that autism was linked to the measles, mumps and rubella vaccine. Although this was retracted in 2010 and is now considered fraud, it had a huge impact on public perception and gave ammunition to anti-vaccination campaigners.

Graph of citations per year of Dr Andrew Wakefield's fraudulent 1998 article published in The Lancet, that tried to link autism to vaccines. After a small drop following partial retraction in 2004, citations continued to rise, even after full retraction in 2010 (click to embiggen)
The most cited article in the study was Dr Andrew Wakefield’s fraudulent 1998 paper that tried to link autism to vaccines, with citations continuing to rise even after retraction (image by Fang et al, PNAS)

In order to keep up with today’s relatively high number of retractions (about 1 in 10,000, compared with 1 in 100,000 in 1977), a website has been created, called Retraction Watch.

If these mistakes can be caught early enough, whether deliberate or not, then it’s hoped that the only damage will be to the reputations scientists involved.

Pot plants fight pollution

Indoor plants make homes or offices more pleasant to be in, but they can also make them healthier by removing pollutants from the air.

The air you breathe when inside is actually more polluted than that outside. It contains all the fossil fuel emissions you get on the street, but in addition it has extra CO2 from people breathing out, as well as things called volatile organic compounds.

Volatile organic compounds, or VOCs, are chemicals that evaporate from plastic or synthetic furniture, fabrics, fittings, paints, varnishes, solvents, and so on. They include substances like benzene – a known carcinogen – as well as toluene, ethylbenzene and xylene.

Research by a team at the University of Technology, Sydney, has studied the ability for potted plants to remove these volatile chemicals. They used both laboratory settings with closed containers and real-world office settings, with a number of different plants, including Spathiphyllum wallisii ‘Sweet Chico’ (Peace Lily), Dracaena deremensis ‘Janet Craig’, Zamioculcas zamiifolia (Aroid Palm), Monstera deliciosa and Sansevieria trifasciata (Mother-in-law’s Tongue or Snake Plant).

Potted plant Dracaena deremensis 'Janet Craig' flowering (click to embiggen)
One of the species used in the study, Dracaena deremensis ‘Janet Craig’ (photo by Nick J. Howe, via Wikimedia Commons)

In the offices they found that for high concentrations of VOCs (greater than 100 parts per billion), the pot plants could reduce them by 50-75%.

Interestingly though, the species of plant didn’t matter – instead, it’s what they call the ‘plant microcosm’, as bacteria in the soil or potting mix digest the VOCs. This means that generally the bigger the pot, the more pollution will be removed – although, there appears to be a limit after which adding more soil with more bacteria won’t remove more VOCs.

Only about two standard-sized pot plants were needed to service an average 12 square metre office – an indoor jungle with dozens of plants was not required.

The plants have another benefits too, like removing CO2 (although that requires them to be placed in sunshine to photosynthesise), reducing dust levels, stabilising temperature and humidity, and reducing noise.

With all that and the ability to remove toxic chemicals, how can you go wrong?


Wood RA, Burchett MD, Alquezar R, Orwell RL, Tarran J & Torpy F 2006, “The potted-plant microcosm substantially reduces indoor air VOC pollution: I. office field-study”, Water, Air, and Soil Pollution, vol. 175, no. 1-4, pp. 163-180, DOI: 10.1007/s11270-006-9124-z

Orwell RL, Wood RA, Burchett MD, Tarran J & Torpy F 2006, “The potted-plant microcosm substantially reduces indoor air VOC pollution: II. laboratory study”, Water, Air, and Soil Pollution, vol. 177, no. 1-4, pp. 59-80, DOI: 10.1007/s11270-006-9092-3

Burchett MD, Torpy F, Brennan, J & Craig A 2010, Greening the great indoors for human
health and wellbeing, Final report to Horticulture Australia Ltd

Stretching credulity

Quick news-you-can-use today: the bulk of research shows that stretching before or after exercise doesn’t prevent injury or muscle soreness, or improve performance. In fact, stretching before exercise may increase the risk of injury.

And yes, you should warm up before exercise, but stretching is not a warm-up.

Woman enjoying a hamstring stretch while balanced on one leg (click to embiggen)
Stretching may feel great – and look impressive – but it won’t prevent injuries or improve athletic performance (Photo by lululemon athletica, via Wikimedia Commons)
Flexibility is one thing that stretching may help, although whether that has any benefits itself is not proven. Its popularity despite lack of evidence leads to the the following curious statement in the 2008 Physical Activity Guidelines for Americans (chapter 4):

“Flexibility is an important part of physical fitness… For this reason, flexibility activities are an appropriate part of a physical activity program, even though they have no known health benefits and it is unclear whether they reduce risk of injury.”

But one thing on which most of us would agree is that stretching feels good. That may be enough motivation itself – after all, it’s probably why animals do it. Just don’t expect other benefits.

For very thorough, exhaustive and well-written further reading, see Quite a Stretch, by Paul Ingraham.

More references after the jump…

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