(Press-News.org) A small piece of freshly cut sapwood can filter out more than 99 percent of the bacteria E. coli from water, according to a paper published in PLOS ONE on February 26, 2014 by Michael Boutilier and Jongho Lee and colleagues from MIT.
Researchers were interested in studying low-cost and easy-to-make options for filtering dirty water, a major cause of human mortality in the developing world. The sapwood of pine trees contains xylem, a porous tissue that moves sap from a tree's roots to its top through a system of vessels and pores. To investigate sapwood's water-filtering potential, researchers collected white pine branches, stripped the outer bark, and cut them into small inch-long sections. They then mounted each in plastic tubing, sealed and secured, and filtered water through that either contained small particles or E. coli bacteria.
The authors found that sapwood filtered out particles greater than 70 nanometers wide, but was unable to separate out 20-nanometer particles, suggesting that there is a particle size limit to what coniferous sapwood can filter. Sapwood also filtered out more than 99% of E. coli from water, which mostly accumulated in the first few millimeters of the wood in what are known as pit membranes. The small- branch filtration system produced water at rates up to four liters of clean drinking water a day, typically enough for one person. However, the authors caution that only hydrated sapwood (and not dried-out wood) will filter out contaminants.
"There's huge variation between plants," says Rohit Karnik, senior author on the paper. "There could be much better plants out there that are suitable for this process. Ideally, a filter would be a thin slice of wood you could use for a few days, then throw it away, and replace at almost no cost. It's orders of magnitude cheaper than the high-end membranes (currently) on the market today."
INFORMATION:
Adapted by PLOS ONE from press release by Jennifer Chu, MIT News Office
Citation: Boutilier MSH, Lee J, Chambers V, Venkatesh V, Karnik R (2014) Water Filtration Using Plant Xylem. PLoS ONE 9(2): e89934. doi:10.1371/journal.pone.0089934
Financial Disclosure: This work was supported by the James H. Ferry, Jr. Fund for Innovation in Research Education award to R.K. administered by the Massachusetts Institute of Technology. SEM imaging was performed at the Harvard Center for Nanoscale Systems, a member of the National Nanotechnology Infrastructure Network (NNIN), which is supported by the National Science Foundation under NSF award no. ECS-0335765. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.
Competing Interest Statement: The authors have declared that no competing interests exist.
PLEASE LINK TO THE SCIENTIFIC ARTICLE IN ONLINE VERSIONS OF YOUR REPORT (URL goes live after the embargo ends):http://dx.plos.org/10.1371/journal.pone.0089934
Tree branch filters water
Pine tree sapwood filters bacteria from contaminated water
2014-02-27
ELSE PRESS RELEASES FROM THIS DATE:
Waterbirds' hunt aided by specialized tail
2014-02-27
The convergent evolution of tail shapes in diving birds may be driven by foraging style, according to a paper published in PLOS ONE on February 26, 2014 by Ryan Felice and Patrick O'Connor from Ohio University.
Birds use their wings and specialized tail to maneuver through the air while flying. It turns out that the purpose of a bird's tail may have also aided in their diversification by allowing them to use a greater variety of foraging strategies. To better understand the relationship between bird tail shape and foraging strategy, researchers examined the tail skeletal ...
MIT researchers make a water filter from the sapwood in tree branches
2014-02-27
If you've run out of drinking water during a lakeside camping trip, there's a simple solution: Break off a branch from the nearest pine tree, peel away the bark, and slowly pour lake water through the stick. The improvised filter should trap any bacteria, producing fresh, uncontaminated water.
In fact, an MIT team has discovered that this low-tech filtration system can produce up to four liters of drinking water a day — enough to quench the thirst of a typical person.
In a paper published this week in the journal PLoS ONE, the researchers demonstrate that a small ...
Study finds social-media messages grow terser during major events
2014-02-27
In the last year or two, you may have had some moments — during elections, sporting events, or weather incidents — when you found yourself sending out a flurry of messages on social media sites such as Twitter.
You are not alone, of course: Such events generate a huge volume of social-media activity. Now a new study published by researchers in MIT's Senseable City Lab shows that social-media messages grow shorter as the volume of activity rises at these particular times.
"This helps us better understand what is going on — the way we respond to things becomes faster ...
Humans have a poor memory for sound
2014-02-27
Remember that sound bite you heard on the radio this morning? The grocery items your spouse asked you to pick up? Chances are, you won't.
Researchers at the University of Iowa have found that when it comes to memory, we don't remember things we hear nearly as well as things we see or touch.
"As it turns out, there is merit to the Chinese proverb 'I hear, and I forget; I see, and I remember," says lead author of the study and UI graduate student, James Bigelow.
"We tend to think that the parts of our brain wired for memory are integrated. But our findings indicate ...
DNA test better than standard screens in identifying fetal chromosome abnormalities
2014-02-27
BOSTON (Feb. 27) – A study in this week's New England Journal of Medicine potentially has significant implications for prenatal testing for major fetal chromosome abnormalities. The study found that in a head-to-head comparison of noninvasive prenatal testing using cell free DNA (cfDNA) to standard screening methods, cfDNA testing (verifi® prenatal test, Illumina, Inc.) significantly reduced the rate of false positive results and had significantly higher positive predictive values for the detection of fetal trisomies 21 and 18.
A team of scientists, led by Diana W. Bianchi, ...
More evidence that vision test on sidelines may help diagnose concussion
2014-02-26
PHILADELPHIA – A simple vision test performed on the sidelines may help determine whether athletes have suffered a concussion, according to a study released today that will be presented at the American Academy of Neurology's 66th Annual Meeting in Philadelphia, April 26 to May 3, 2014.
The study provides more evidence that the King-Devick test, a one-minute test where athletes read single-digit numbers on index cards, can be used in addition to other tests to increase the accuracy in diagnosing concussion.
For the study, 217 members of the University of Florida men's ...
IU study ties father's age to higher rates of psychiatric, academic problems in kids
2014-02-26
BLOOMINGTON, Ind. -- An Indiana University study in collaboration with medical researchers from Karolinska Institute in Stockholm has found that advancing paternal age at childbearing can lead to higher rates of psychiatric and academic problems in offspring than previously estimated.
Examining an immense data set -- everyone born in Sweden from 1973 until 2001 -- the researchers documented a compelling association between advancing paternal age at childbearing and numerous psychiatric disorders and educational problems in their children, including autism, ADHD, bipolar ...
Improved prescribing and reimbursement practices in China
2014-02-26
Bethesda, MD — Pay-for-performance—reimbursing health care providers based on the results they achieved with their patients as a way to improve quality and efficiency—has become a major component of health reforms in the United States, the United Kingdom, and other affluent countries. Although the approach has also become popular in the developing world, there has been little evaluation of its impact. A new study, being released today as a Web First by Health Affairs, examines the effects of pay-for-performance, combined with capitation, in China's largely rural Ningxia ...
3-D microgels 'on-demand' offer new potential for cell research
2014-02-26
Stars, diamonds, circles.
Rather than your average bowl of Lucky Charms, these are three-dimensional cell cultures generated by an exciting new digital microfluidics platform, the results of which have been published in Nature Communications this week by researchers at the University of Toronto. The tool, which can be used to study cells in cost-efficient, three-dimensional microgels, may hold the key to personalized medicine applications in the future.
"We already know that the microenvironment can greatly influence cell fate," says Irwin A. Eydelnant, recent doctoral ...
New gas-phase compounds form organic particle ingredients
2014-02-26
Helsinki/Jülich/Leipzig. Scientists made an important step in order to better understand the relationships between vegetation and climate. So-called extremely low-volatility organic compounds, which are produced by plants, could be detected for the first time during field and laboratory experiments in Finland and Germany. These organic species contribute to the formation of aerosol that can affect climate and air quality, they report in this week's issue of the journal Nature. The results may help to explain discrepancies between observations and theories about how volatile ...
LAST 30 PRESS RELEASES:
Intra-arterial tenecteplase for acute stroke after successful endovascular therapy
Study reveals beneficial microbes that can sustain yields in unfertilized fields
Robotic probe quickly measures key properties of new materials
Climate change cuts milk production, even when farmers cool their cows
Frozen, but not sealed: Arctic Ocean remained open to life during ice ages
Some like it cold: Cryorhodopsins
Demystifying gut bacteria with AI
Human wellbeing on a finite planet towards 2100: new study shows humanity at a crossroads
Unlocking the hidden biodiversity of Europe’s villages
Planned hydrogen refuelling stations may lead to millions of euros in yearly losses
Planned C-sections increase the risk of certain childhood cancers
Adults who have survived childhood cancer are at increased risk of severe COVID-19
Drones reveal extreme coral mortality after bleaching
New genetic finding uncovers hidden cause of arsenic resistance in acute promyelocytic leukemia
Native habitats hold the key to the much-loved smashed avocado’s future
Using lightning to make ammonia out of thin air
Machine learning potential-driven insights into pH-dependent CO₂ reduction
Physician associates provide safe care for diagnosed patients when directly supervised by a doctor
How game-play with robots can bring out their human side
Asthma: patient expectations influence the course of the disease
UNM physician tests drug that causes nerve tissue to emit light, enabling faster, safer surgery
New study identifies EMP1 as a key driver of pancreatic cancer progression and poor prognosis
XPR1 identified as a key regulator of ovarian cancer growth through autophagy and immune evasion
Flexible, eco-friendly electronic plastic for wearable tech, sensors
Can the Large Hadron Collider snap string theory?
Stuckeman professor’s new book explores ‘socially sustainable’ architecture
Synthetic DNA nanoparticles for gene therapy
New model to find treatments for an aggressive blood cancer
Special issue of Journal of Intensive Medicine analyzes non-invasive respiratory support
T cells take aim at Chikungunya virus
[Press-News.org] Tree branch filters waterPine tree sapwood filters bacteria from contaminated water