General science thread

Quote:

Spraying crops with bacterial or yeast spores that have unique DNA “barcodes” would make food safer by allowing the source of food poisoning to be rapidly identified, says a team at Harvard University. They have genetically engineered the bacteria, developed a rapid test for them and shown that the spores – which are inert and harmless – persist and remain detectable, even on cooked food.

It’s estimated that almost 1 in 10 people worldwide get food poisoning and more than 400,000 die of it every year, according to the World Health Organization. Tracing the source of contamination is difficult and can take many weeks, says Jason Qian at Harvard University.

His team has genetically engineered strains of Bacillus subtilis bacteria and Saccharomyces cerevisiae yeast to give them unique DNA “barcode” sequences. These species are very common and also form tough, long-lasting spores.

The spores of the barcoded microbes are inert. The genes required for B. subtilis to come out of dormancy have been deleted, and the yeast spores are heat-treated to kill them. Both types are also unable to make a key amino acid, so can only grow when fed it.

The team then sprayed the spores on various surfaces including sand, soil, carpet and wood. They were able to detect them three months later even on surfaces that were swept or vacuumed, or subjected to simulated wind or rain.

Quote:

Negative thinking behaviors such as rumination about the past and worry about the future were measured in over 350 people over the age of 55 over a two-year period. About a third of the participants also underwent a PET (positron emission tomography) brain scan to measure deposits of tau and beta amyloid, two proteins which cause Alzheimer's disease, the most common type of dementia.

The scans showed that people who spent more time thinking negatively had more tau and beta amyloid buildup, worse memory and greater cognitive decline over a four-year period compared to people who were not pessimists.

Quote: rxwine

Does negative thinking lead to alzheimers?

Interesting, but I'll reserve judgment for now on that conclusion.

https://www.msn.com/en-us/health/health-news/negative-thinking-linked-to-dementia-in-later-life-study-finds/ar-BB15avrr?ocid=spartanntp

Quote: kenarman

Two things wrong with that idea. Is it cause or effect for the negative thinking? Maybe people in the early stages of dementia are more pessimistic because of the disease. The second thing is a promising Alzheimer's drug that was in the 3rd phase of testing and was reducing the amyloid buildup didn't effect the progress of the Alzheimer's. The tests were cancelled and the drug abandoned as ineffective. The scientists are now not sure that the assumption that amyloid buildup was the cause are starting to wonder if the amyloid buildup is just an effect.

Quote: rxwine

I told my dentist I thought maybe dementia might be related to not flossing.

Tooth infection has a short path to the brain.

(hasn't taken hold yet)

Quote: Gandler

Its probably true. Gum health has a direct correlation to brain health.

Quote: kenarman

Probably the teeth not the gums. Everyone I see missing 1/2 their teeth looks dumb as ---k ;-)

Quote: kenarman

Probably the teeth not the gums. Everyone I see missing 1/2 their teeth looks dumb as ---k ;-)

Quote: petroglyph

The first thing I think when I see poor teeth is, it is an obvious sign of low money.

Anyone, especially in the summer can don a set of clean new clothes and shave. But missing teeth takes time an money to solve.

I've spent a fortune in my mouth over the years, then radiation blew them back out. Now I'm screwed.