Science News
Headlines
. Junk foods can harm young children's brains
. Plastic waste is literally filling the world
. 60 year old Arecibo Astronomical Observatory to be closed
. Vaccines for Covid-19 are on the way
Read more about them below.

Junk foods can harm young children's brains
Adolescents are young children in the age group from 10 to 19. They are more sensitive than any other age group to foods with a lot of processed fat and sugar.  says. Amy Reichelt is part of a group of scientists around the world who have been studying why.
Teenage brains are still developing. The prefrontal cortex in the front part of their brains are not fully grown. So they cannot assess risks and control their actions as easily as adults do. In addition, there is a natural chemical called dopamine that is called the feel-good chemical. So not only can teens not resist that junk food, but eating it releases dopamine to make them get that feel-good sensation. So it becomes doubly difficult to stop eating such food.
Mouse brains on fat and sugar
In 2017, Reichelt was part of a team that fed adolescent mice high-fat foods to see how it affected their brains.
One group of mice ate a diet in which a huge 63 percent of their calories came from fat. A second group ate a healthy diet. Apart from becoming fat, the first group of mice performed worse on memory tests, especially tests involving what is called as working memory.
Working memory helps you remember which things you need to buy at the store. Or what time you said you’d meet your friends.  It’s also important for reasoning and decision-making. And it involves the prefrontal cortex — that’s the same brain area that helps make decisions.
Then the researchers looked at the animals’ brains. Here they found important differences in reelin, a chemical that helps brain cells chat with each other. Mice on a high-fat diet had roughly 35 percent less reelin in their prefrontal cortex compared to mice on a healthy diet.  The high-fat diet may have made the prefrontal cortex in these mice work less effectively.
Reichelt found similar behavioral effects in adolescent rats that got daily access to a sugary drink. They showed less desire to explore new things than did rats not fed sugar.

Human brains on junk food
Human children showed one more negative effect of junk food. In one 2013 study, children who ate more junk food were found to have nearly 50 percent more chance to show signs of mental depression: they want to lie around, not wanting to do any thing, and not finding enjoyment in simple activity. This may be caused by inflammation due to eating processed foods.

Good fat, bad fat
The good news is that you can make food choices that support a healthy brain. 
“The brain is the most fat-rich organ we have,” notes Alexandra Richardson.  “And where does it get its fats? From what we put in our bodies.” Foods like fish, nuts, seeds and other foods rich in Omega-3 fats help the brain grow and improve mental health.
Research shows exercise can be a good way to fend off damage from junk food. 
Two important things happen in the brain when we exercise. The first is that the brain’s reward system — the one that feels good when we do something we like — becomes less sensitive to food so that it does not find high-calorie foods as rewarding.
Exercise can also improve strong connections between the prefrontal cortex and other brain regions. When that happens, the prefrontal cortex “can exert control better,” says Lowe. In other words, better connections help us weigh risks, make informed decisions on how to act, and curb our impulses. So put that junk food away, eat healthy, and exercise: and watch those brain cells sharpen up!

. Plastic waste is literally filling the world
Plastics are everywhere: that's because we use and throw millions of tons of plastic away. Estimates made say that we use about 300 million tons of plastic every year. The plastics live practically for ever, breaking down into small centimeter size pieces, and damaging the delicate digestive systems of many marine animals.  Now, these microplastics (plastic pieces less than half centimeter in size) have been found at Everest Base Camp (5500 m above mean sea level) for a long time. Recently, they have been found at a height of 8,440 m above sea level (the height of Mt Everest is 8,848 m), nearly at the top.
Plastic is not only floating on large areas of the Pacific ocean. It has also been found as deep as in the Mariana Trench in the western Pacific ocean, 10,890 m below sea level, which is among the deepest places in the world.
Millions of pieces of microplastics have been found in Arctic ice. Not just around us: plastics are also in us: a 2019 study concluded that an average American consumes about 50,000 pieces of microplastic a year.  Where does this come from? From the microplastics in the water that we drink, and in food such as fish, and salt, which come from the sea, etc.  Surely it is time that we stopped using so much plastic and looked for more environmentally friendly alternatives.

60 year old Arecibo Astronomical Observatory to be closed
Construction for the Arecibo Observatory was started in 1960 in Arecibo in Puerto Rico, in the Caribbean ocean. The radio telescope built there has a 305 m spherical reflector dish and so was the world's largest single-aperture dish till 2016. It has been working since Nov 1963, and will be shut down soon since some of its cables are damaged beyond repair. 
The telescope has been used to make many important scientific discoveries.
. In 1964, it was used to study the rotation period of Mercury.
. In 1968, studies on the Crab Pulsar by Lovelace proved that neutron stars exist.
. The most prominent one was the discovery in 1974 of the binary pulsar PSR-B1913+16 by Hulse and Taylor, for which they got the Nobel Prize. (The discovery led to a better understanding of gravity, and tested Einstein's theory of relativity). 
. In 1982, Backer discovered the first millisecond pulsar, which spins 642 times a second!
. In 1989, it imaged an asteroid for the first time.
. In 1990, the first exo-planets (planets outside our solar system) were found.
. In 2008, emission of hydrogen cyanide molecules from a distant galaxy was found.
. In 2011, radio emissions from a brown dwarf star were observed for the first time.
. It also studied exotic issues such as attempting to find life outside Earth! It was also featured in Hollywood movies.
Unfortunately, it appears that the structure is old and cannot be easily repaired. So it will be dismantled. Its loss will be keenly felt among astronomers and scientists, who have used it to look at the sky to answer questions about our Universe.

Vaccines for Covid-19 are on the way
It has been a year and the world is still in the grip of the Covid19 pandemic. Scientists the world over are racing to find a vaccine. A vaccine trains and prepares the body's immune system to recognise and fight bacteria and viruses. Once you have taken a vaccine, if your body is infected by the virus or bacteria against which the vaccine is effective, the immune system rapidly responds to the attack and prevents you from getting sick.
There are more than 100 groups working on different vaccine candidates.  All of them are first tested on animals before they reach the human trial phase. Even then, there are three phases of trials that a vaccine has to pass before it can be approved for use. A vaccine not only must prevent the infection, it must also not have serious side-effects. It takes time to find out all the side-effects and decide whether they are major or not.
The COVAX initiative is a part of the World Health Organization’s (WHO) efforts (together with the Coalition for Epidemic Preparedness Innovations (CEPI); Gavi, the Vaccine Alliance). The goal is to work with vaccine manufacturers to offer low-cost COVID-19 vaccines to countries.
Currently, CEPI’s candidates from companies Inovio, Moderna, CureVac, Institut Pasteur/Merck/Themis, AstraZeneca/University of Oxford, Novavax, University of Hong Kong, Clover Biopharmaceuticals, and University of Queensland/CSL are part of the COVAX initiative. There are further candidates being evaluated in the COVAX Facility from the United States and internationally. Many of them are in phase-3 trials.
It has already been announced that the Oxford vaccine is effective, and may work 70-90% of the time, although their phase-3 trials are yet to conclude. Pfizer have also announced that their vaccine is 95% effective against Covid19. Moderna's vaccine has a similar efficacy. However Pfizer's vaccine needs to be stored at an incredibly low temperature of -70 degrees, otherwise the vaccine components may break down. This will pose a serious challenge for countries such as India. Moderna's vaccine, on the other hand, can be stored at -20 degrees, in a standard freezer, and even survives up to one month in an ordinary fridge. In contrast, the Oxford vaccine, though less efficient, can be stored at normal fridge temperature. It is expected to be much cheaper than the other two, especially since it will also be manufactured in India by the Serum Institute and may cost about Rs 500.
The results look promising and it is likely that a vaccine will be available soon, across the world.
Sources: 
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