One of the top science stories of 2008 from Discover magazine:
#41: A Synthetic Genome Is Built From Scratch
This is one of the top Science news in 2008. Scientists at JCVI synthesize the genome of Mycoplasma genitalium using E. coli and then yeast. Of course, there’s a long way to go from DNA to a functional organism. From transcription to translation, modification or mutations take place to give unexpected results. The researchers have also taken measures to make sure that this synthetic genome can’t survive outside the lab (Adding their names and “JCVI” in the genetic code was pretty cool). While controversial, this development can tell us a lot about a cell on the molecular level in future research.
While the petrolium fuel price is skyrocketing with no end in sight, the search for a reliable alternative energy source is essential. Hydrogen is one of the most popular candidates.
So how does a hydrogen fuel cell work? (more…)
From Scientific American’s Can Bovine Growth Hormone Help Slow Global Warming?:
There is currently a debate raging over the safety of bovine growth hormone. The U.S. Food and Drug Administration (FDA) in 1993 ruled that it was not harmful and could be injected into cows to improve their milk production. But some studies have linked it with a risk of mastitis (udder infection) in cows, requiring the use of antibiotics that may in turn be contributing to the evolving resistance of bacteria to the drugs.
Bovine growth hormone is also known to stimulate the production of insulinlike growth factor 1 (IGF1) by the liver; some studies have shown that high levels of IGF1 in the bloodstream may heighten the risk of prostate and breast cancers as well as a woman’s chance of conceiving twins. As a result of consumer concerns, farmers in Australia, Canada, the European Union and New Zealand do not inject their cows with bovine growth hormone.
Back in high school (That was the 90′s. Geez, I feel so old), I read that high milk consumption had been linked to development of breast cancer. So it seems that growth hormone could be the culprit to blame. If the farmers can really sustain the same amount of milk production and keep the greenhouse gas emission in check without depending on injecting the cows with GH, everyone will be happy. And then I can keep drinking milk with an eased mind. I really don’t want to think about what to eat for breakfast. I’m happy with the bowl of cereal every morning.
PLA = polylactic acid, is made from fermented plant (mostly corn) starch and considered a better alternative than the traditional petroleum-based plastic, polyethylene terephthalate (PET), used to make bottles. To make PLA, dextrose is extracted from corn starch, and them lactic acid is produced as a by-product in a fermentation process. Lactic acid is converted to lactide. The molecules then link together to form polymers that are polylactic acid. Therefore, PLA comes from a renewable carbon source, it reduces greenhouse gas emissions, and it does not release toxic gas when incinerated. The idea has been around for decades, but thanks to the technology that can now produce 1 pound of PLA for less than $1, more retailers are looking into PLA as their packaging option.
Don’t get too excited just yet. (more…)
OK, I’ve written about a terrifying burden on the environment that is plastic bags. Now a Canadian high school student may find a plausible solution to this problem — by isolating bacteria that break down plastic bags in 3 months, instead of millions of years. (more…)
Source: Scientific American’s No Fair! My Serotonin Level Is Low
In the last post, we found out that serotonin controls appetite and metabolism. In fact, 80% of the body’s serotonin is found in the gut. But the neurotransmitter has many more functions, including roles in depression, anger, sleep, etc. Now the scientists have discovered that it can also affect the perception of fairness.
The subjects in the experiment are offered an amount of money that has been unevenly split. Normally, people would reject lowball offers like 20% or 30% of the money. When the subjects are depleted of serotonin, they turn down even 80% of the money, indicating that their judgement of fairness is seriously skewed.
Serotonin influences so many emotions that it is difficult to pinpoint a single function to study. It is amazing how a small chemical can affect our body, mind, and life.