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Página 41 de 950

  • Linguagens

    Inglês

    Read Text I below and answer the  question that follow it.


    Text I


    Jonathan Haidt: How to make the 'anxious generation' happy again


    Academics researching wellbeing have for a long time almost unanimously agreed on one thing: over the typical lifetime, happiness tends to follow a U-shaped curve, peaking at 30, plummeting at age 50, before spiking again after 70. It’s a pattern replicated using data going back as far as the 1970s in almost 150 countries.

    But around 2011, researchers noticed an astonishing reversal in this trend. “This empirical regularity has been replaced by a monotonic decrease in ill-being by age,” they reported in an NBER working paper. In plain English, younger people today are unhappier, both compared to previous generations and to their older peers. Or, to quote the title of the most recent book from Jonathan Haidt, Professor of Ethical Leadership at New York University, they are the anxious generation […].

    Today, rather than playing with their friends, kids stay at home on their devices. Instead of hearing chatter and laughter in the corridor of schools, we hear the gentle tapping of screens. The social isolation many of us experienced during pandemic-induced lockdowns was nothing new for children, Haidt said. “They began social distancing as soon as they got smartphones.”

    The good news for parents is that, while this trend is worrying, it is not inevitable. There are things we can do. “We can turn this around with four new norms,” Haidt proposed.

    The first norm is a commitment to not give our children a smartphone until they are at least 14. “Give them a flip-phone if you want to, so they can call and text you,” he said. “But don’t give the entire world access to your child.” The second is to not allow our children to use social media until they are at least 16. “Social media is wildly inappropriate for children — you have strangers trying to talk to them, cyberbullying, explosive drama.”

    The third norm is that schools should be a phone-free environment. “All schools need to be phone free from bell to bell — from the morning when kids arrive to the end when they leave,” Haidt explained.

    And finally, the fourth norm involves going back to a time where parents felt more comfortable letting their kids walk to the shops or play outside with friends. “The fourth norm is to give them much more independence in the real world,” he said. “Ultimately, our mission is to restore childhood: the kind of wonderful, fun, exciting childhood we all had, which was full of conflicts, failures, exploration, adventure, risk-taking, thrills and all those emotions that you experienced not with your parents, but when you were out, away from your secure home base.”


    Adapted from https://www.weforum.org/stories/2025/01/jonathan-haidt-digitaltechnology-social-media-childhood/
    Based on Text I, mark the statements below as true (T) or false (F).


    ( ) Happiness among young people has increased compared to previous years.

    ( ) Today, children prefer playing with their friends at school to using a smartphone.

    ( ) According to Haidt, social media is harmful to children.


    The statements are, respectively: 
    Escolha uma alternativa para a questão b4c37d92-f9
  • Linguagens

    Português

    Texto I


    Os erros continuam...


    Já mais de uma vez, temos procurado apontar erros da imprensa, em textos da redação e de colaboradores, na esperança de vê-los desaparecer. Repetem-se com uma monotonia desanimadora. Já não falo da chamada crase, entregue aos cuidados de colegas. Quase ninguém mais sabe acentuar o a, se com acento agudo ou grave, ou mesmo sem nenhum acento. Nem querem saber, ao que parece. Saliente-se que os principais órgãos da imprensa têm editado uma espécie de manual de redação para o público interno, mas os resultados não têm correspondido à expectativa. Demais, é preciso contar com a contribuição dos colaboradores... Vou, pois, continuar malhando em ferro frio e a trazer mais algumas incorreções postas em letra de forma.


    ELIA, Sílvio. 50 textos errados e corrigidos, Rio de Janeiro: Gráfica Olímpica.

    Saliente-se que os principais órgãos da imprensa têm editado uma espécie de manual de redação para o público interno, (...)


    Nesse segmento, o termo público interno se refere aos
    Escolha uma alternativa para a questão b4a86e39-f9
  • Linguagens

    Português

    Texto I


    Os erros continuam...


    Já mais de uma vez, temos procurado apontar erros da imprensa, em textos da redação e de colaboradores, na esperança de vê-los desaparecer. Repetem-se com uma monotonia desanimadora. Já não falo da chamada crase, entregue aos cuidados de colegas. Quase ninguém mais sabe acentuar o a, se com acento agudo ou grave, ou mesmo sem nenhum acento. Nem querem saber, ao que parece. Saliente-se que os principais órgãos da imprensa têm editado uma espécie de manual de redação para o público interno, mas os resultados não têm correspondido à expectativa. Demais, é preciso contar com a contribuição dos colaboradores... Vou, pois, continuar malhando em ferro frio e a trazer mais algumas incorreções postas em letra de forma.


    ELIA, Sílvio. 50 textos errados e corrigidos, Rio de Janeiro: Gráfica Olímpica.

    O Texto I afirma que o mau emprego da crase é um problema que se repete com uma monotonia desanimadora.


    Assinale a frase em que o emprego da crase está incorreto.
    Escolha uma alternativa para a questão b4a39836-f9
  • Linguagens

    Português

    O texto seguinte servirá de base para responder à questão.

    Exames podem detectar doenças oculares silenciosas; veja cuidados

    A saúde ocular deve ser acompanhada desde o nascimento até a terceira idade, especialmente diante do uso crescente de telas. Para prevenir doenças oculares silenciosas, é essencial manter uma rotina de exame de saúde como acuidade visual, pressão ocular, biomicroscopia e fundoscopia.

    Juliana Oliveira, oftalmologista, destaca que o primeiro exame obrigatório no Brasil é o teste do olhinho, feito ao nascer. A partir dos três anos, é indicada avaliação anual para detectar precocemente alterações visuais, inclusive glaucoma, catarata e problemas na retina, especialmente na velhice.

    Hábitos saudáveis — como boa alimentação e prática de atividades físicas — ajudam a preservar a visão. As doenças mais comuns incluem ametropias não corrigidas, conjuntivites, glaucoma e catarata senil. Sintomas como dor, vermelhidão, secreção e perda de visão parcial ou total exigem atenção médica imediata.

    O uso precoce e excessivo de telas eleva o risco de miopia, olho seco e distúrbios do sono. Para minimizar os efeitos, recomenda-se limitar o tempo diante de telas, fazer pausas regulares e, com orientação médica, usar óculos com filtro de luz azul, colírios específicos e lentes para controle da miopia.

    Fonte: https://www.cnnbrasil.com.br/saude/exames-podem-detectar-doencasoculares-silenciosas-veja-cuidados/.ADAPTADO. 
    Para "prevenir" doenças oculares silenciosas, é essencial "manter" uma rotina de exame de saúde como acuidade visual, pressão ocular, biomicroscopia e fundoscopia.


    De acordo com as regras de regência verbal, os verbos destacados nesta frase funcionam, respectivamente, como:
    Escolha uma alternativa para a questão fe46c7a0-f2
  • Linguagens

    Português

    O texto seguinte servirá de base para responder à questão.

    Exames podem detectar doenças oculares silenciosas; veja cuidados

    A saúde ocular deve ser acompanhada desde o nascimento até a terceira idade, especialmente diante do uso crescente de telas. Para prevenir doenças oculares silenciosas, é essencial manter uma rotina de exame de saúde como acuidade visual, pressão ocular, biomicroscopia e fundoscopia.

    Juliana Oliveira, oftalmologista, destaca que o primeiro exame obrigatório no Brasil é o teste do olhinho, feito ao nascer. A partir dos três anos, é indicada avaliação anual para detectar precocemente alterações visuais, inclusive glaucoma, catarata e problemas na retina, especialmente na velhice.

    Hábitos saudáveis — como boa alimentação e prática de atividades físicas — ajudam a preservar a visão. As doenças mais comuns incluem ametropias não corrigidas, conjuntivites, glaucoma e catarata senil. Sintomas como dor, vermelhidão, secreção e perda de visão parcial ou total exigem atenção médica imediata.

    O uso precoce e excessivo de telas eleva o risco de miopia, olho seco e distúrbios do sono. Para minimizar os efeitos, recomenda-se limitar o tempo diante de telas, fazer pausas regulares e, com orientação médica, usar óculos com filtro de luz azul, colírios específicos e lentes para controle da miopia.

    Fonte: https://www.cnnbrasil.com.br/saude/exames-podem-detectar-doencasoculares-silenciosas-veja-cuidados/.ADAPTADO. 
    A saúde ocular exige atenção constante desde a infância até a velhice, principalmente devido ao uso excessivo de telas no cotidiano.


    De acordo com o texto base, analise as afirmações a seguir e assinale a alternativa correta.
    Escolha uma alternativa para a questão fe43f4e2-f2
  • Linguagens

    Português

    O texto seguinte servirá de base para responder à questão.

    Exames podem detectar doenças oculares silenciosas; veja cuidados

    A saúde ocular deve ser acompanhada desde o nascimento até a terceira idade, especialmente diante do uso crescente de telas. Para prevenir doenças oculares silenciosas, é essencial manter uma rotina de exame de saúde como acuidade visual, pressão ocular, biomicroscopia e fundoscopia.

    Juliana Oliveira, oftalmologista, destaca que o primeiro exame obrigatório no Brasil é o teste do olhinho, feito ao nascer. A partir dos três anos, é indicada avaliação anual para detectar precocemente alterações visuais, inclusive glaucoma, catarata e problemas na retina, especialmente na velhice.

    Hábitos saudáveis — como boa alimentação e prática de atividades físicas — ajudam a preservar a visão. As doenças mais comuns incluem ametropias não corrigidas, conjuntivites, glaucoma e catarata senil. Sintomas como dor, vermelhidão, secreção e perda de visão parcial ou total exigem atenção médica imediata.

    O uso precoce e excessivo de telas eleva o risco de miopia, olho seco e distúrbios do sono. Para minimizar os efeitos, recomenda-se limitar o tempo diante de telas, fazer pausas regulares e, com orientação médica, usar óculos com filtro de luz azul, colírios específicos e lentes para controle da miopia.

    Fonte: https://www.cnnbrasil.com.br/saude/exames-podem-detectar-doencasoculares-silenciosas-veja-cuidados/.ADAPTADO. 
    As doenças mais comuns incluem ametropias não corrigidas, conjuntivites, glaucoma e catarata senil.


    Sintaticamente, é correto afirmar que, nesta frase: 
    Escolha uma alternativa para a questão fe4163ff-f2
  • Linguagens

    Literatura

    A cultura brasileira é alimentada por produções importantes desde o século XIX. Uma das opções a seguir reúne corretamente obras e autores que promoveram nossa cultura e que tiveram expressão nos séculos XIX e XX predominantemente. Assinale-a:
    Escolha uma alternativa para a questão 7921e6b8-df
  • Linguagens

    Português

    Texto 1

    Antes que seja tarde

    Sérgio Vaz


    Figura 1 de 2 da questão de Português, CEDERJ 2025, Interpretação de Textos
    Figura 2 de 2 da questão de Português, CEDERJ 2025, Interpretação de Textos

    Fragmento adaptado. VAZ, Sérgio. Flores de alvenaria. 2.ed. São Paulo: Global Editora, 2021. p. 71-73.
    Leia o trecho para responder à questão:


    “Fico em silêncio quando a multidão desinformada pede redução da maioridade penal, porém, ela sabe que, se não educarmos nossas crianças, vão ter que prendê-las com 16, depois 14, depois 12, até que não tenhamos mais crianças nas ruas.” (Linhas 25 - 30). 


    Assinale a opção em que a substituição do conectivo “porém” altera o sentido do enunciado:
    Escolha uma alternativa para a questão 78dc259d-df
  • Linguagens

    Português

    Texto 1

    Antes que seja tarde

    Sérgio Vaz


    Figura 1 de 2 da questão de Português, CEDERJ 2025, Figuras de Linguagem
    Figura 2 de 2 da questão de Português, CEDERJ 2025, Figuras de Linguagem

    Fragmento adaptado. VAZ, Sérgio. Flores de alvenaria. 2.ed. São Paulo: Global Editora, 2021. p. 71-73.
    A prosa de Sérgio Vaz, caracteristicamente poética, apresenta várias figuras de linguagem. Marque a opção em que os elementos sublinhados NÃO CORRESPONDEM à figura apontada:
    Escolha uma alternativa para a questão 78d98f1e-df
  • Linguagens

    Inglês

    The rise of reusable rockets: transforming the economics of space travel

    By Adam Stockley


    Various theoretical designs of reusable launch vehicles (rockets) have been tested during the history of space flight, but they generally proved too expensive or impractical to implement.  

    In the 21st century, the rise in industry privatisation led to several companies taking the lead in reusable launcher development. Their focus is on fully-reusable systems.

    The potential of reusable rockets to transform the economics of space travel should be evident. Even so, let’s break down the benefits and drawbacks of this technology to understand more.


    The Benefits of Reusable Rockets


    The most obvious benefit of a reusable rocket is cost savings. Unsurprisingly, it’s much cheaper to refurbish and relaunch a rocket than it is to build a new one. Reusable rockets also use less fuel than their expendable counterparts, making them comparatively better for the environment.


    The Drawbacks of Reusable Rockets


    The main disadvantage of reusable rockets is their reduced load capacity. By extension, they must be built to survive the difficulties of launch and re-entry, meaning there is much more extra stabilisation equipment. Therefore, the rockets are heavier.


    The Long-Term Viability of Reusable Launchers


    The bottom line is that now we have a firmer understanding of the concept of reusable launchers, their potential impact is limitless. However, there are some issues to resolve in terms of extra weight and reduced load capacity, but the space industry is very near to perhaps its biggest revolution in terms of cost reduction and accessibility.


    Available at: https://www.kdcresource.com/insights-events/therise-of-reusable-rockets-transforming-the-economics-of-spacetravel/. Access 16 out. 2024. Adapted. 
    The main theme of the text is the:
    Escolha uma alternativa para a questão 0dd173f8-df
  • Linguagens

    Português

    Texto 2


    Conexão

    Era uma palavra mais bonita

    Antes de existir o wi-fi.

    Zack Magiezi

    Disponível em https://es.pinterest.com/pin/conexo-- 82472236917172490/. Acesso em: 24 set. 2024.
    Em “Era uma palavra mais bonita...”, o verbo está
    Escolha uma alternativa para a questão 0d6e83f2-df
  • Linguagens

    Português

    Texto 2


    Conexão

    Era uma palavra mais bonita

    Antes de existir o wi-fi.

    Zack Magiezi

    Disponível em https://es.pinterest.com/pin/conexo-- 82472236917172490/. Acesso em: 24 set. 2024.
    Está correto afirmar que, no poema de Zack Magiezi, a palavra
    Escolha uma alternativa para a questão 0d6be71b-df
  • Linguagens

    Português

    Texto 1

    Conexão à moda antiga

    Martha Medeiros

    08/09/2024 

    Imagem da questão de Português, CEDERJ 2025, Sintaxe

    Disponível em https://oglobo.globo.com/ela/marthamedeiros/coluna/2024/09/conexao-a-moda-antiga.ghtml. Acesso em: 24 set. 2024. Fragmento.
    “Por isso, já não levo tão em conta o currículo, e sim o jeito da pessoa.” (Linhas 7-8) Aponte a opção em que a substituição do conectivo “por isso” MANTÉM o sentido original do enunciado acima:
    Escolha uma alternativa para a questão 0d66cf9b-df
  • Linguagens

    Português

    Texto 1

    Conexão à moda antiga

    Martha Medeiros

    08/09/2024 

    Imagem da questão de Português, CEDERJ 2025, Interpretação de Textos

    Disponível em https://oglobo.globo.com/ela/marthamedeiros/coluna/2024/09/conexao-a-moda-antiga.ghtml. Acesso em: 24 set. 2024. Fragmento.
    A expressão “Difícil peneirar uma pepita de ouro em meio a tanto pedregulho” (Linhas 5- 7) se baseia em um(a):
    Escolha uma alternativa para a questão 0d643e21-df
  • Linguagens

    Português

    Texto 1

    Conexão à moda antiga

    Martha Medeiros

    08/09/2024 

    Imagem da questão de Português, CEDERJ 2025, Interpretação de Textos

    Disponível em https://oglobo.globo.com/ela/marthamedeiros/coluna/2024/09/conexao-a-moda-antiga.ghtml. Acesso em: 24 set. 2024. Fragmento.
    Martha Medeiros é considerada uma das maiores cronistas brasileiras da atualidade. Na crônica “Conexão à moda antiga”, a autora, predominantemente, 
    Escolha uma alternativa para a questão 0d607cfb-df
  • Linguagens

    Inglês

    Leia o texto a seguir para responder à questão.



    Back To School But Not To Screens: States Ramp Up Cellphone Bans




            Work has been easier for public high school teacher Brian Kerekes since last August, when he first experienced the impacts of a newly enacted Florida law to restrict students’ cellphone use during class. The longtime statistics instructor, who started a new school year on Monday, now spends less time circling the classroom policing students and more time educating them on how to gather and interpret data.



            Before Florida passed the ban in May 2023 — becoming the first of at least eight U.S. states to prohibit or restrict cellphone use in schools — phones proved a constant disruption in Kerekes’ classroom at Tohopekaliga High School in the central Florida city of Kissimmee.



            “Students were either using them to talk to someone in a different class or talk to someone on the other side of the room or just to zone out, get on TikTok or whatever,” Kerekes, who's been a teacher for 17 years, said in an interview.



            Fellow teachers nationwide face the same challenge, which explains why more states and districts are moving to limit or outright ban cellphones in the classroom, and even during the school day altogether.

            


            The rules will look different from state to state and district to district, but all stem from the same concerns.



            Seventy-two percent of high school teachers cite cellphones as a major distraction in the classroom, according to a fall 2023 Pew Research Center study. Educators also worry that constant access to social media can adversely impact kids’ mental health.



            U.S. Surgeon General Vivek Murthy went so far as to issue a health advisory last year, warning that enough evidence exists to show social media can be unsafe for children and teens. “We are in the middle of a national youth mental health crisis,” he said, “and I am concerned that social media is an important driver of that crisis, one that we must urgently address.”



            While social media can connect kids, make them feel less alone and offer an entertaining and creative outlet, it also exposes them to harmful content, Murthy pointed out in the advisory released by the U.S. Department of Health and Human Services. And, as educators such as Kerekes note, some students use their phones to bully fellow students online during the school day, and in the most extreme cases, to set up fights and film them.

    The hope is that cellphone bans will reduce such incidents. Kerekes said he’s hearing they have.



    Fonte: KATZ, Leslie. Back To School But Not To Screens: States Ramp Up Cellphone Bans. Forbes, 13 ago. 2024. Disponível em: https://www.forbes.com/sites/lesliekatz/2024/08/13/back-to-school-but-not-to-screens-more-students-face-cellphone-bans/

    Ao transpor a frase “Seventy-two percent of high school teachers cite cellphones as a major distraction in the classroom" para a voz passiva, a construção CORRETA é

    Escolha uma alternativa para a questão 8ec3d45a-d0
  • Linguagens

    Inglês

    Leia o texto a seguir para responder à questão.



    Back To School But Not To Screens: States Ramp Up Cellphone Bans




            Work has been easier for public high school teacher Brian Kerekes since last August, when he first experienced the impacts of a newly enacted Florida law to restrict students’ cellphone use during class. The longtime statistics instructor, who started a new school year on Monday, now spends less time circling the classroom policing students and more time educating them on how to gather and interpret data.



            Before Florida passed the ban in May 2023 — becoming the first of at least eight U.S. states to prohibit or restrict cellphone use in schools — phones proved a constant disruption in Kerekes’ classroom at Tohopekaliga High School in the central Florida city of Kissimmee.



            “Students were either using them to talk to someone in a different class or talk to someone on the other side of the room or just to zone out, get on TikTok or whatever,” Kerekes, who's been a teacher for 17 years, said in an interview.



            Fellow teachers nationwide face the same challenge, which explains why more states and districts are moving to limit or outright ban cellphones in the classroom, and even during the school day altogether.

            


            The rules will look different from state to state and district to district, but all stem from the same concerns.



            Seventy-two percent of high school teachers cite cellphones as a major distraction in the classroom, according to a fall 2023 Pew Research Center study. Educators also worry that constant access to social media can adversely impact kids’ mental health.



            U.S. Surgeon General Vivek Murthy went so far as to issue a health advisory last year, warning that enough evidence exists to show social media can be unsafe for children and teens. “We are in the middle of a national youth mental health crisis,” he said, “and I am concerned that social media is an important driver of that crisis, one that we must urgently address.”



            While social media can connect kids, make them feel less alone and offer an entertaining and creative outlet, it also exposes them to harmful content, Murthy pointed out in the advisory released by the U.S. Department of Health and Human Services. And, as educators such as Kerekes note, some students use their phones to bully fellow students online during the school day, and in the most extreme cases, to set up fights and film them.

    The hope is that cellphone bans will reduce such incidents. Kerekes said he’s hearing they have.



    Fonte: KATZ, Leslie. Back To School But Not To Screens: States Ramp Up Cellphone Bans. Forbes, 13 ago. 2024. Disponível em: https://www.forbes.com/sites/lesliekatz/2024/08/13/back-to-school-but-not-to-screens-more-students-face-cellphone-bans/

    Referring to the establishment of a national youth mental health crisis, U.S. Surgeon General Vivek Murthy stated: “| am concerned that social media is an important driver of that crisis, one that we must urgently address". In this sentence, the modal verb MUST indicates

    Escolha uma alternativa para a questão 8ec1080c-d0
  • Linguagens

    Inglês

    Leia o texto a seguir para responder à questão.



    Back To School But Not To Screens: States Ramp Up Cellphone Bans




            Work has been easier for public high school teacher Brian Kerekes since last August, when he first experienced the impacts of a newly enacted Florida law to restrict students’ cellphone use during class. The longtime statistics instructor, who started a new school year on Monday, now spends less time circling the classroom policing students and more time educating them on how to gather and interpret data.



            Before Florida passed the ban in May 2023 — becoming the first of at least eight U.S. states to prohibit or restrict cellphone use in schools — phones proved a constant disruption in Kerekes’ classroom at Tohopekaliga High School in the central Florida city of Kissimmee.



            “Students were either using them to talk to someone in a different class or talk to someone on the other side of the room or just to zone out, get on TikTok or whatever,” Kerekes, who's been a teacher for 17 years, said in an interview.



            Fellow teachers nationwide face the same challenge, which explains why more states and districts are moving to limit or outright ban cellphones in the classroom, and even during the school day altogether.

            


            The rules will look different from state to state and district to district, but all stem from the same concerns.



            Seventy-two percent of high school teachers cite cellphones as a major distraction in the classroom, according to a fall 2023 Pew Research Center study. Educators also worry that constant access to social media can adversely impact kids’ mental health.



            U.S. Surgeon General Vivek Murthy went so far as to issue a health advisory last year, warning that enough evidence exists to show social media can be unsafe for children and teens. “We are in the middle of a national youth mental health crisis,” he said, “and I am concerned that social media is an important driver of that crisis, one that we must urgently address.”



            While social media can connect kids, make them feel less alone and offer an entertaining and creative outlet, it also exposes them to harmful content, Murthy pointed out in the advisory released by the U.S. Department of Health and Human Services. And, as educators such as Kerekes note, some students use their phones to bully fellow students online during the school day, and in the most extreme cases, to set up fights and film them.

    The hope is that cellphone bans will reduce such incidents. Kerekes said he’s hearing they have.



    Fonte: KATZ, Leslie. Back To School But Not To Screens: States Ramp Up Cellphone Bans. Forbes, 13 ago. 2024. Disponível em: https://www.forbes.com/sites/lesliekatz/2024/08/13/back-to-school-but-not-to-screens-more-students-face-cellphone-bans/

    De acordo com as informações presentes no texto, depreende-se que

    Escolha uma alternativa para a questão 8ebba124-d0
  • Linguagens

    Inglês

    How companies are embracing generative AI for employees…or not


        New York CNN - Companies are struggling to deal with the rapid rise of generative AI, with some rushing to embrace the technology as workflow tools for employees while others shun it - at least for now.

        As generative artificial intelligence - the technology that underpins ChatGPT and similar tools - seeps into seemingly every corner of the internet, large corporations are grappling with whether the increased efficiency it offers outweighs possible copyright and security risks. Some companies are enacting internal bans on generative AI tools as they work to better understand the technology, and others have already begun to introduce the trendy tech to employees in their own ways.

    Disponível em: https://edition.cnn.com/2023/09/22/tech/generative-ai-corporate-policy/index.html. Acesso em: 30 mar. 2025. Adaptado.


    In the text, the term enacting is equivalent to which word?  
    Escolha uma alternativa para a questão ebfc86a8-cd
  • Linguagens

    Inglês

    Bacteria use antimicrobial agent to kill competition


        Hospitalized patients are often given antibiotics, which reduces the diversity of bacteria in their microbiomes. It also allows drug-resistant strains to gain a foothold and take over. Enterococcus faecium is a gut bacterium that can cause lethal infections if it gets into the bloodstream. Vancomycin-resistant E. faecium (VREfm), which is resistant to vancomycin and multiple other antibiotics, is a growing problem in healthcare settings. Populations of VREfm within healthcare systems are known to change over time. But the factors driving these changes aren’t well understood.

        NIH-supported researchers at the University of Pittsburgh Medical Center have been collecting and sequencing bacterial DNA from hospitalized patients through the Enhanced Detection System for Healthcare-Associated Transmission (EDS-HAT). This helps clinicians to recognize and stop potential outbreaks. As part of this effort, researchers collected more than 700 VREfm samples between 2017 and 2022. A team at the university, led by Dr. Daria Van Tyne, used data from these samples to track VREfm evolution. Their findings appeared in Nature Microbiology on March 21, 2025.

        Genome sequencing of the samples identified 42 different genetic lineages, or strains, of VREfm. Almost half of the samples were closely related to at least one other sample. This suggests a high level of transmission within the hospital. Before 2020, about a third of the samples belonged to the strain ST17. From 2020 onward, two new strains, ST80 and ST117, began to take over. By the end of 2022, these two strains made up more than 80% of all samples, while ST17 was not detected.

        The researchers found that ST80 and ST117 could kill ST17, but not vice versa. Further examination revealed that ST80 and ST117, but not ST17, produce an antimicrobial peptide (a short chain of amino acids) called bacteriocin T8. Both in laboratory cultures and the guts of mice, strains that made bacteriocin T8 outcompeted strains that didn’t.

        Next, the team analyzed more than 15,000 publicly available VREfm genomes collected worldwide between 2002 and 2022. They saw the same trend, with ST17 replaced by ST80 and ST117. This suggests that the changes observed in a single hospital reflected global trends.

    Disponível em: https://www.nih.gov/news-events/nih-research-matters/bacteria-use-antimicrobialagent-kill-competition. Acesso em: 3 abr. 2025.


    According to the text, how do strains ST80 and ST117 outcompete ST17?  
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