Science

The Greater Chennai Corporation has decided to launch robotic science classes in its schools. The Corporation runs 281 schools in the city.

The classes will be started in five schools in the first phase and extended to all higher secondary schools later.

At least 300 children in Chennai Higher Secondary School in Thiruvanmiyur, Chennai Girls Higher Secondary School in Saidapet, Chennai Higher Secondary School in Taramani, Chennai Girls Higher Secondary School in Nungambakkam and Chennai Higher Secondary School in Maduvankarai will be covered in the first phase of the initiative. Classes will be held twice a week.

Increase in admissions

Meanwhile, the Corporation schools in many zones have registered an increase in the number of students. For example, in one zone, the student strength had increased by 12% in schools. Teachers said the classrooms had become inadequate for admitting more students. As a result, teachers have come up with the suggestion of holding classes in two shifts.

Teachers said the student strength had gone up because of introduction of modern facilities. Many parents, who had been unable to pay the fees in private schools, had started admitting their children in Corporation schools, they pointed out.

For every sighting of a Burmese python in Florida’s Everglades, there could be up to 1,000 that we do not see, according to the top scientist at conservation group the Everglades Foundation.

The huge numbers underline the challenge facing conservation workers in controlling the fast-expanding population of the invasive species in the tropical wetlands of the Everglades, an ideal habitat for the snakes.

Steve Davis, the Everglades Foundation’s chief science officer, told Newsweek that the Florida Python Challenge, an annual event that awards hunters with cash prizes for catching the most and the biggest pythons, is a good way to keep numbers down.

“The detection capacity for pythons is very low. I’ve seen estimates of 100 to 1,000 other pythons for every one python we see—1,000 being the extreme high end.

“That range may have changed as efforts like the python challenge help to improve our understanding of where they are and how to find them,” Davis said.

Burmese pythons, which are native to southeast Asia, became an invasive species in the Everglades after being brought over as pets in the 1990s. Because they have no predators in the U.S. and can produce clutches of up to 100 eggs, python numbers have exploded across the Everglades. There are thought to be over 100,000 in the state of Florida.

In January 2012, the U.S. Fish and Wildlife Service banned the importation of four species of pythons, including the Burmese python. However officials admit that they should have acted much sooner.

“People might argue the ultimate boundaries, but there’s no part of this state that you can point at and say that pythons couldn’t live here,” Frank Mazzotti, an associate professor of wildlife ecology in the University of Florida’s Institute of Food and Agricultural Sciences, said in a 2012 news release. “They’re capable of surviving anywhere in Florida, they’re capable of incredible movement—and in a relatively short period.”

This year’s Florida Python Challenge, being held from August 5 to 14, was announced on June 16 by Governor Ron DeSantis , who said the pythons “wreak havoc on the ecosystem”.

At a press conference about the 2022 hunt, he said: “We’ve worked hard on conserving Florida’s natural resources and to make sure that we were taking a unique piece of property that God has given us and leaving it to the next generation better than we found it.”

Burmese pythons outcompete native wildlife for food, which has led to enormous drops in the populations of native mammals, including raccoons and opossums.

The Florida Python Challenge is one attempt by the Florida government to eradicate at least some of the invasive populations . Burmese pythons, however, blend in extremely well with the marshy environment of the Everglades, meaning that they are difficult for hunters to detect.

The Florida Fish and Wildlife Conservation Commission (FWC) encourages people to kill Burmese pythons on private land, so long as it is done humanely. The FWC also runs a detector dog team, which goes out five days a week to hunt down pythons.

But these methods have done little to reduce the python population in Florida. In November last year, it was reported Burmese pythons had expanded their range north, with sightings in the Arthur R. Marshall Loxahatchee National Wildlife Refuge.

Burmese pythons use constriction to kill their prey, such as mice and birds, squeezing the animal until it suffocates. It is rare for a Burmese python to attack a human without being provoked, although there have been cases of captive Burmese pythons killing people in the U.S.

The Florida Python Challenge involves participants killing as many pythons as possible, with cash prizes for those who catch the most, and longest, snakes. The catcher of the most snakes wins $2,500, and the longest snake gets a $1,500 prize.

The Python Challenge suggests using captive bolt stunners or air guns to kill pythons. The use of firearms is prohibited during the 2022 competition.

The snakes must be killed humanely , or a participant will be disqualified. The FWC defines a humane killing as one resulting in the python losing consciousness immediately, followed by destroying its brain by ‘pithing’: inserting a metal rod into the brain and moving it around to completely destroy the tissue.

Attendees are taught how to correctly kill the pythons humanely as part of an online training course that is mandatory to enter the competition. Last year over 600 people registered to participate and 223 snakes were removed from the Everglades.

What happens to our genes when we die? They stop working, would be a reasonable assumption. But a surprising, new study shows that even when our bodies show no signs of life, genes can continue to be active.

Related: Where Do You Go When You Die? The Increasing Signs That Human Consciousness Remains After Death

Currently, little is known about how death affects gene expression. The presence of a gene in our DNA doesn’t automatically guarantee an end result, like eye color. Rather, it’s through the process of gene expression that they essentially provide a plan for how cells will function. And some of our genes are active, or expressed, while others are not.

A better understanding of exactly when our genes cease their activity could help forensic scientists pinpoint time of death, and add to what we know about how genes work.

To determine whether genes remain active after death, a group of international researchers measured how strongly a gene was being expressed. The team used donated tissue samples from the American Genotype-Tissue Expression project, a government-funded project to study genetics that includes tissue samples from patients (both alive and dead).

The researchers looked at 36 blood and tissue samples from 540 deceased donors, who had been dead for up to 29 hours , and reviewed records on how soon the specimens were collected after death. The paper was

According to the study, published in February in Nature , activity didn’t stop all at once. Gene expression in muscle tissue, for example, stopped soon after death, but activity in colon tissue increased.

“The response to the death of the organism is quite tissue specific,” study co-author and molecular biologist Roderic Guigó of the Center for Genomic Regulation in Barcelona, Spain, told Science magazine.

Guigó and his team determined that subcutaneous fat, lung, thyroid and skin tissues most accurately reflected someone’s time of death.

Based on their findings, the team created an algorithm to better estimate the time of death that’s accurate to about nine minutes, according to microbial ecologist Jennifer DeBruyn, of the University of Tennessee in Knoxville. DeBruyn was not involved in the study but explained to Science News that this finding could help better identify someone’s time of death.

Currently, forensic scientists look at internal body temperature, measure muscle stiffness and study environmental factors to determine when someone died. But improving accuracy is a constant focus for the community. Solving the biological mystery of how our genes behave after death could help solve criminal mysteries, too.

Clinically, we understand death to mean the state that takes hold after our hearts stop beating. Blood circulation comes to a halt, we don’t breathe, our brains shut down—and that’s what divides the states we occupy from one moment (alive) to the next (dead). Philosophically, though, our definition of death hinges on something else: the point past which we’re no longer able to return. Those two were more or less the same until about 50 years ago, when we saw the advent of CPR . Today, someone’s heart can stop and they can be dead, and then they can come back.

Modern resuscitation was a game-changer for emergency care, but it also blew apart our understanding of what it means to be dead. Without many people returning from the dead to show us otherwise, it was natural to assume, from a scientific perspective, that our consciousness dies at the same time as our bodies. Over the last few years, though, scientists have seen repeated evidence that once you die, your brain cells take days, potentially longer, to reach the point past which they’ve degraded too far to ever be viable again. This does not mean you’re not dead; you are dead. Your brain cells, however, may not be.

“What’s fascinating is that there is a time, only after you and I die, that the cells inside our bodies start to gradually go toward their own process of death,” Dr. Sam Parnia, director of critical care and resuscitation research at New York University Langone Medical Center, told Newsweek . “I’m not saying the brain still works, or any part of you still works once you’ve died. But the cells don’t instantly switch from alive to dead. Actually, the cells are much more resilient to the heart stopping—to the person dying—than we used to understand.”

Scientists working on human cadavers have from time to time observed genes that are active after death, according to University of Washington microbiology professor Peter Noble. For a 2017 study published in Open Biology , Noble and his colleagues tested mice and zebrafish and found not just a handful, but a combined total of 1,063 genes that remained active, in some cases for up to four days after the subject had died. Not only did their activity not dissipate—it spiked.

“We didn’t anticipate that,” Noble told Newsweek . “Can you imagine, 24 hours after [time of death] you take a sample and the transcripts of the genes are actually increasing in abundance? That was a surprise.”

Quite a few of these are developmental genes, Noble said, raising the fascinating and slightly disturbing possibility that in the period immediately following death, our bodies start reverting to the cellular conditions that were present when we were embryos. Noble found that certain animals’ cells, post-mortem, remained viable for weeks. The research suggests a “step-wise shutdown,” by which parts of us die gradually, at different rates, rather than all at once.

Exactly why some cells are more resilient to death than others can’t yet be said. In a 2016 study published in the Canadian Journal of Biological Sciences , doctors recounted shutting off life support for four terminally ill patients, only to have one of the patients continue emitting delta wave bursts—the measurable electrical activity in the brain we normally experience during deep sleep—for more than 10 minutes after the patient had been pronounced dead; no pupil dilation, no pulse, no heartbeat. The authors were at a loss for a physiological explanation.

Parnia’s research has shown that people who survive medical death frequently report experiences that share similar themes: bright lights; benevolent guiding figures; relief from physical pain and a deeply felt sensation of peace. Because those experiences are subjective, it’s possible to chalk them up to hallucinations. Where that explanation fails, though, is among the patients who have died on an operating table or crash cart and reported watching—from a corner of the room, from above—as doctors tried to save them, accounts subsequently verified by the (very perplexed) doctors themselves.

How these patients were able to describe objective events that took place while they were dead, we’re not exactly sure, just as we’re not exactly sure why certain parts of us appear to withstand death even as it takes hold of everything else. But it does seem to suggest that when our brains and bodies die, our consciousness may not, or at least not right away.

“I don’t mean that people have their eyes open or that their brain’s working after they die,” Parnia said. “That petrifies people. I’m saying we have a consciousness that makes up who we are—our selves, thoughts, feelings, emotions—and that entity, it seems, does not become annihilated just because we’ve crossed the threshold of death; it appears to keep functioning and not dissipate. How long it lingers, we can’t say.”