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May 10, 2013

Carbon dioxide levels in atmosphere reach 3 million-year high

Carbon Dioxide Level Passes Long-Feared Milestone - NYTimes.com
Scientific monitors reported that the gas had reached an average daily level that surpassed 400 parts per million — just an odometer moment in one sense, but also a sobering reminder that decades of efforts to bring human-produced emissions under control are faltering. The best available evidence suggests the amount of the gas in the air has not been this high for at least three million years, before humans evolved, and scientists believe the rise portends large changes in the climate and the level of the sea. “It symbolizes that so far we have failed miserably in tackling this problem,” said Pieter P. Tans, who runs the monitoring program at the National Oceanic and Atmospheric Administration that reported the new reading. Ralph Keeling, who runs another monitoring program at the Scripps Institution of Oceanography in San Diego, said a continuing rise could be catastrophic. “It means we are quickly losing the possibility of keeping the climate below what people thought were possibly tolerable thresholds,” he said.

May 07, 2013

Birds in menopause develop male coloration

Science is amazing. The long-running mystery of why birds seemingly change sex
When people began dissecting female birds that suddenly displayed male plumage, the found atrophied or nonfunctioning ovaries. When they removed the ovaries from healthy female birds, many of them began developing male plumage. Estrogen is the only thing that keeps female birds camouflaged in browns and grays. As ovaries age and stop working, or if they for some reason sustain damage, the sudden loss of estrogen causes females to grow vivid plumage, and even start calling or crowing like male birds. This is most often observed in chickens — since they're the most commonly observed birds — but it's been shown to happen in golden pheasants and even peacocks. As females peahens age, they will often grow full peacock tails, the way male peacocks do, although they won't fan them. We think of male plumage as an extravagance that is added to birds. It seems as if it's more of a default that needs to be hormonally suppressed to keep from showing up.

May 05, 2013

Study suggests link between pesticides and autism, Alzheimer's

A tenuous link, but an intriguing one. Study Links Monsanto’s Roundup to Autism, Parkinson’s and Alzheimer’s – EcoWatch: Cutting Edge Environmental News Service
A new review of hundreds of scientific studies surrounding glyphosate—the major component of Monsanto’s Roundup herbicide—sheds light on its effects within the human body. The paper describes how all of these effects could work together, and with other variables, trigger health problems in humans, including debilitating diseases like gastrointestinal disorders, diabetes, heart disease, obesity, Parkinson’s and Alzheimer’s disease. Glyphosate impairs the cytochrome P450 (CYP) gene pathway, which creates enzymes that help to form and also break down molecules in cells. There are myriad important CYP enzymes, including aromatase (the enzyme that converts androgen into estrogen) and 21-Hydroxylase, which creates cortisol (stress hormone) and aldosterone (regulates blood pressure). One function of these CYP enzymes is also to detoxify xenobiotics, which are foreign chemicals like drugs, carcinogens or pesticides. Glyphosate inhibits these CYP enzymes, which has rippling effects throughout our body. Because the CYP pathway is essential for normal functioning of various systems in our bodies, any small change in its expression can lead to disruptions. For example, humans exposed to glyphosate have decreased levels of the amino acid tryptophan, which is necessary for active signaling of the neurotransmitter serotonin. Suppressed serotonin levels have been associated with weight gain, depression and Alzheimer’s disease.

Portraits synthesized from DNA found on discarded chewing gum

Stranger Visions: DNA Collected from Found Objects Used to Create 3D Portraits | Colossal
So I extract the DNA in the lab and then I amplify certain regions of it using a technique called PCR – Polymerase Chain Reaction. This allows me to study certain regions of the genome that tend to vary person to person, what are called SNPs or Single Nucleotide Polymorphisms. I send the results of my PCR reactions off to a lab for sequencing and what I get back are basically text files filled with sequences of As, Ts, Cs, and Gs, the nucleotides that compose DNA. I align these using a bioinformatics program and determine what allele is present for a particular SNP on each sample. Then I feed this information into a custom computer program I wrote which takes all these values which code for physical genetic traits and parameterizes a 3d model of a face to represent them. For example gender, ancestry, eye color, hair color, freckles, lighter or darker skin, and certain facial features like nose width and distance between eyes are some of the features I am in the process of studying. I add some finishing touches to the model in 3d software and then export it for printing on a 3d printer. I use a Zcorp printer which prints in full color using a powder type material, kind of like sand and glue.