Tag Archives: chemistry

Where are the Senior Female Scientists

Why Are Senior Female Scientists So Heavily Outnumbered by Men? by Anna Kushnir

There is some funny math in the world of academic science. Take my graduate school for example: My class was made up of eight people — seven women and one man, or 7 to 1. He was Snow White and we were the seven dwarves — each with a remarkably appropriate nickname. I was Grumpy, should you be curious to know.

Snow White and at least four of the dwarves have continued on to postdoctoral research jobs. That is a 4 to 3 ratio of women who went on to do a post-doc to those that chose alternate career paths.

Everything is adding up so far, right? Lots of women are around. Lots of science is being done. All is well. The next set of numbers is slightly puzzling, however. That is the ratio of female to male professors in our department, at a well-respected academic institution, is 48 to 7 men to women.

The proportion of female faculty in her department, 14 percent, is exactly equal to the overall average from the top fifty US chemistry departments.

From her blog: Lab Life: I thought I wanted to be “normal”

The majority of researchers, in my experience, think that stress level, pressure, and time commitments all drop by a factor of ten the moment you step outside of the chemical-smeared walls of a lab. I have come to realize that’s a misconception. It’s just not true. I think that whenever one wants a career instead of a job, time, stress, pressure, and worry are the price to pay.

If all I wanted was a job with a steady income, I am pretty sure I could get it. I would be well-rested and calm, but would I be happy? Would I be alright staying put where I am, with nothing pushing me to reach the next step or rise to the next level? I don’t think so.

I have heard the words ‘ambition’ and ‘drive’ described as derogatory, when applied to people. Unfortunately, I think those are apt words to describe me (in addition to ‘tired’ and ‘often occasionally cranky’). It was an important thing for me to understand about myself and come to terms with. It’s just who I am.

Related: A Decade of Progress for Women in ScienceWomen Working in Scienceposts on scientists at workWomen Choosing Other Fields Over Engineering and Mathscience internships

Plants can Signal Microbial Friends for Help

When under attack, plants can signal microbial friends for help

Researchers at the University of Delaware have discovered that when the leaf of a plant is under attack by a pathogen, it can send out an S.O.S. to the roots for help, and the roots will respond by secreting an acid that brings beneficial bacteria to the rescue.

In a series of laboratory experiments, the scientists infected the leaves of the small flowering plant Arabidopsis thaliana with a pathogenic bacterium, Pseudomonas syringae. Within a few days, the leaves of the infected plants began yellowing and showing other symptoms of disease.

However, the infected plants whose roots had been inoculated with the beneficial microbe Bacillus subtilis were perfectly healthy. Farmers often add B. subtilis to the soil to boost plant immunity. It forms a protective biofilm around plant roots and also has antimicrobial properties, according to Bais.

Using molecular biological tools, the scientists detected the transmission of a long-distance signal, a “call for help,” from the leaves to the roots in the plants that had Bacillus in the soil. The roots responded by secreting a carbon-rich chemical–malic acid.

All plants biosynthesize malic acid, Bais explains, but only under specific conditions and for a specific purpose–in this case, the chemical was actively secreted to attract Bacillus. Magnified images of the roots and leaves showed the ratcheted-up defense response provided by the beneficial microorganisms.

“Plants can’t move from where they are, so the only way they can accrue good neighbors is through chemistry,” Bais notes.

Related: Researchers Learn What Sparks Plant GrowthSecret Life of MicrobesSymbiotic relationship between ants and bacteriaBacterium Living with High Level Radiation

Measuring Protein Bond Strength with Optical Tweezers

Using a light touch to measure protein bonds

MIT researchers have developed a novel technique to measure the strength of the bonds between two protein molecules important in cell machinery: Gently tugging them apart with light beams. “It’s really giving us a molecular-level picture of what’s going on,” said Matthew Lang, an assistant professor of biological and mechanical engineering

The researchers studied the interactions between the proteins by pinning one actin filament to a surface and controlling the motion of the second one with a beam of light. As the researchers tug on a bead attached to the second filament, the bond mediated by the actin-binding protein eventually breaks.

With this technique, the researchers can get a precise measurement of the force holding the proteins together, which is on the order of piconewtons (10-12 newtons).

Related: Neuroengineers Use Light to Silence Overactive NeuronsSlowing Down LightFoldit, the Protein Folding Game

Pesticide Laced Fertiliser Ruins Gardens

Home-grown veg ruined by toxic fertiliser

Aminopyralid, which is found in several Dow products, the most popular being Forefront, a herbicide, is not licensed to be used on food crops and carries a label warning farmers using it not to sell manure that might contain residue to gardeners. The Pesticides Safety Directorate, which has issued a regulatory update on the weedkiller, is taking samples from affected plants for testing.

Problems with the herbicide emerged late last year, when some commercial potato growers reported damaged crops. In response, Dow launched a campaign within the agriculture industry to ensure that farmers were aware of how the products should be used. Nevertheless, the herbicide has now entered the food chain. Those affected are demanding an investigation and a ban on the product. They say they have been given no definitive answer as to whether other produce on their gardens and allotments is safe to eat.

It appears that the contamination came from grass treated 12 months ago. Experts say the grass was probably made into silage, then fed to cattle during the winter months. The herbicide remained present in the silage, passed through the animal and into manure that was later sold. Horses fed on hay that had been treated could also be a channel.

Related: Effect of People on Other SpeciesPigs Instead of PesticidesPeak SoilFlushed Drugs Pollute Water

Plastic Balls for the Resevoir

photo of Los Angeles resevoir

This photo looks like a April fools joke but I think it is real. Los Angeles Drops 400,000 Balls in Reservoir to Fight Suspected Carcinogen

So why deploy these balls — which are typically used by airports to prevent bird congregation on runways — in particular? Some of the other alternatives, such as a large tarp or metal cover, were considered too costly or impractical. The balls, on the other hand, are (relatively) cheap — costing 40 cents each — and are safe for drinking water; black is also the only color able to deflect UV rays.

The DWP has ordered 6.5 million of these balls, 3 million of which it plans on using to blanket the Ivanhoe and Elysian reservoirs. So, yeah, this probably isn’t the best solution for the city’s water woes but, given the circumstances, maybe the only “realistic” option in the short-term.

Los Angeles Department of Water and Power drops 400,000 balls onto Ivanhoe Reservoir:

The water needs to be shaded because when sunlight mixes with the bromide and chlorine in Ivanhoe’s water, the carcinogen bromate forms, said Pankaj Parekh, DWP’s director for water quality compliance. Bromide is naturally present in groundwater and chlorine is used to kill bacteria, he said, but sunlight is the final ingredient in the potentially harmful mix.

Photo by (Irfan Khan / Los Angeles Times)

Call me a bit skeptical. Adding a huge number of plastic balls to a water supply in order to try and prevent a chemical reaction caused by added chemicals and sunlight seems a bit crazy to me. But who know maybe it is a good idea.

Related: Cheap Drinking Water From SeawaterEngineering A Cleaner RiverBoiling Water And Plastic Spikes Bisphenol A LevelsBottled Water Waste

The Chemistry of Hair Coloring

Scientists Develop the First Significant Advance in Hair Dye in 50 Years by Kristen Philipkoski

Hair color is serious chemistry. Getting color into that hair shaft is no joke. That’s why Procter & Gamble employs 1,800 “beauty scientists” around the globe. I spoke to two of these beauty scientists this week who told me they have invented a kinder hair color, and that it marks the first significant advance in dye jobs in 50 years.

Small, diffuse color molecules enter the hair, and while they’re inside, they oxidize and form a chemical reaction with a larger color molecule that’s already trapped in there. But the small molecules aren’t all that selective about who they get it on with, and they end up breaking some of the chemical bonds that hold hair together. That releases free radicals that make hair weaker and less able to resist things like aggressive brushing, blow-drying and ironing.

So the beauty scientists came up with a whole new chemistry for getting the lightening molecules inside the hair. First, the new process works at a much lower pH. That makes it less alkaline, so it strips away much less of the lipid coating.