Questões de Concurso

Chagas disease, also known as American trypanosomiasis, is a potentially life-threatening illness caused by the protozoan parasite Trypanosoma cruzi. About 6-7 million people worldwide are estimated to be infected with T. cruzi. The disease is found mainly in endemic areas of 21 continental Latin American countries, where it has been mostly transmitted to humans and other mammals by contact with feces or urine of triatomine bugs (vector-borne), known as kissing bugs, among many other popular names, depending on the geographical area.

Chagas disease is named after Carlos Ribeiro Justiniano Chagas, a Brazilian physician and researcher who discovered the disease in 1909. Chagas disease was once entirely confined to continental rural areas of the Region of the Americas (excluding the Caribbean islands). Due to increased population mobility over previous decades, most infected people now live in urban settings and the infection has been increasingly detected in the United States of America, Canada, and many European and some African, Eastern Mediterranean and Western Pacific countries.

Chagas disease’s transmission is caused by T. cruzi parasites, which are mainly transmitted by contact with feces/urine of infected blood-sucking triatomine bugs. Normally they hide during the day and become active at night when they feed on animal blood, including human blood. They usually bite an exposed area of skin such as the face (hence its common name, kissing bug), and the bug defecates or urinates close to the bite. The parasites enter the body when the person instinctively smears the bug’s feces or urine into the bite, other skin breaks, the eyes, or the mouth. T. cruzi can also be transmitted by consumption of food or beverages contaminated with T. cruzi through, for example, contact with feces or urine of infected triatomine bugs or common opossums. This kind of transmission typically causes outbreaks with more severe cases and mortality; passage from an infected mother to her newborn during pregnancy or childbirth; blood or blood product transfusion from infected donors; some organ transplants using organs from infected donors; and laboratory accidents.

Internet: <who.int> (adapted).

The public school district in Seattle has filed a novel lawsuit against the tech giants behind TikTok, Instagram, Facebook, YouTube and Snapchat, seeking to hold them accountable for the mental health crisis among youth.

Seattle Public Schools filed the lawsuit Friday in U.S. District Court. The 91-page complaint says the social media companies have created a public nuisance by targeting their products to children.

It blames them for worsening mental health and behavioral disorders including anxiety, depression, disordered eating and cyberbullying; making it more difficult to educate students; and forcing schools to take steps such as hiring additional mental health professionals, developing lesson plans about the effects of social media, and providing additional training to teachers.

"Defendants have successfully exploited the vulnerable brains of youth, hooking tens of millions of students across the country into positive feedback loops of excessive use and abuse of Defendants' social media platforms, " the complaint said. "Worse, the content Defendants curate and direct to youth is too often harmful and exploitive ...."

Meta, Google, Snap and TikTok did not immediately respond to requests for comment Saturday.

While federal law — Section 230 of the Communications Decency Act — helps protect online companies from liability arising from what third-party users post on their platforms, the lawsuit argues that provision does not protect the tech giants' behavior in this case.

"Plaintiff is not alleging Defendants are liable for what third-parties have said on Defendants' platforms but, rather, for Defendants' own conduct, " the lawsuit said. "Defendants affirmatively recommend and promote harmful content to youth, such as pro-anorexia and eating disorder content."

The lawsuit says that from 2009 to 2019, there was on average a 30% increase in the number of Seattle Public Schools students who reported feeling "so sad or hopeless almost every day for two weeks or more in a row" that they stopped doing some typical activities.

The school district is asking the court to order the companies to stop creating the public nuisance, to award damages, and to pay for prevention education and treatment for excessive and problematic use of social media.

While hundreds of families are pursuing lawsuits against the companies over harms they allege their children have suffered from social media, it's not clear if any other school districts have filed a complaint like Seattle's.

Internal studies revealed by Facebook whistleblower Frances Haugen in 2021 showed that the company knew that Instagram negatively affected teenagers by harming their body image and making eating disorders and thoughts of suicide worse. She alleged that the platform prioritized profits over safety and hid its own research from investors and the public.

Available at: ttps://www.npr.org/2023/01/08/1147735477/seattlesschools-are-suing-tech-giants-for-harming-young-peoplesmental-health

Elon Musk's web of satellites makes it harder to detect dangerous near-Earth asteroids, scientists have warned.

The number of satellites orbiting Earth has soared from just a few hundred in 1986 to 10,000 today.

Another tenfold increase is expected over the coming decade - much of it driven by Musk's Starlink network.

Starlink is a fleet of satellites which brings internet to people with little or no signal - including troops in Ukraine.

But more than 100 astronomers have now warned against launching more "megaconstellations" of satellites.

The boffins said clogging up the Earth's orbit with satellites could block their telescopes' view of outer space.

Professor Robert McMillan told Space: "Artificial satellites, even those invisible to the naked eye, can obstruct astronomical observations.

"These observations help detect asteroids and understand our place in the universe.

"The potentially long-term environmental harms of deploying tens of thousands of satellites are still unclear."

Light streaks from Starlink have dazzled a California telescope which scans the sky for exploding stars and dangerous near-Earth asteroids.

A study found that Musk's satellites could stop the Zwicky Transient Facility picking up asteroids coming from the sun.

Around one in five snaps from the huge telescope have been affected, Scientific American reports.

Expert Przemek Mróz said: "We don't expect Starlink satellites to affect non-twilight images.

"But if the satellite constellation of other companies goes into higher orbits, this could cause problems for non-twilight observations."

Co-author Tom Prince said: "There is a small chance that we would miss an asteroid or another event hidden behind a satellite streak."

https://www.thesun.co.uk/tech/31609240/elon-musk-satellites-asteroidsscientists/