Os termos sublinhados constituem, respectivamente,
Questões de Concursos
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Técnica impede multiplicação de células e pode ajudar a controlar o câncer
Uma das características do câncer que mais dificulta o seu combate é o crescimento anormal e incontrolável das células doentes. Pesquisadores norte-americanos identificaram uma proteína presente no ciclo de proliferação dos tumores cancerígenos que, ao ser silenciada, pode retardar a evolução rápida e altamente prejudicial da doença. Testes em laboratório feitos com tumores humanos surtiram resultado positivo, o que leva a equipe a acreditar que poderá desenvolver um tratamento mais eficaz contra os carcinomas.
Fonte: Correio Braziliense, 26/05/2017 Disponível em: http://www.correiobraziliense.com.br
Considerando as informações do texto e os conhecimentos relacionados, é correto afirmar:
Thematic Discussion on Nuclear Weapons
The United States remains committed to the goal of nuclear disarmament, and to seeking to create conditions toward that end. And history makes clear that important progress can be made when security conditions allow. The easing of Cold War rivalries allowed the United States and Russia to make significant steps toward the shared dream of eventual nuclear disarmament after decades in which such movement was impossible. Disarmament success is predicated on patience, attention to detail, effective verification, and patient attention to the challenges of effecting the changes in the security environment that are necessary for progress. This last element is critical, considering the crucial role that nuclear deterrence plays in preserving and protecting international peace and security, and the potentially catastrophic consequences were deterrence’s restraining effect to be removed while it still remains necessary.
The “Treaty on the Prohibition of Nuclear Weapons” violates all these tenets. Its obligations are longstanding worded, imprecise, vaguely worded and sometimes internally contradictory, while offering only an empty shell for verification. Worse, it is fundamentally at odds with today’s security challenges. It is not simply an unproductive instrument; it is likely to be a counterproductive one, with the potential to cause lasting harm to the nonproliferation regime and to the cause of disarmament alike.
The ban treaty is based on the premise that addressing crucial international security issues is not necessary for disarmament. Ban treaty proponents would have us believe that we can do away with nuclear deterrence despite - to cite just one example - the danger posed by North Korea’s relentless pursuit of nuclear weapons and associated delivery systems, which stand in flagrant violation of international law.
Furthermore, the Treaty does not contain a credible verification mechanism, demurring on the issue almost entirely. It does run counter to decades of progress in nonproliferation verification by endorsing the International Atomic Energy Agency (IAEA) Comprehensive Safeguards Agreement as its standard for safeguarding nuclear material.
Finally, the ban treaty has the potential to do real damage to the Non Proliferation Treaty (NPT) in other ways. It exacerbates political tensions on disarmament, dividing states into overly-simplified camps of “nuclear weapons supporters” and “nuclear weapons banners,” rather than recognizing shared interests – especially on the challenges involved in creating the conditions that would make possible further disarmament progress. Reinforcing this false dichotomy and worsening the world’s polarization on disarmament will make further progress within the institutions that have been vehicles for success, such as the NPT review process, significantly more difficult.
Inspired by the NPT Preamble’s acknowledgement of the need to ease international tension and strengthen trust between States in order to facilitate disarmament, the United States stands ready to work with others on effective measures to create improved conditions for nuclear disarmament. This work is focused on overcoming technical challenges to make substantive progress when the security conditions improve. We also continue our longstanding work to support and strengthen the global nonproliferation regime against the many challenges it faces today, for who could deny that there can be no way to envision today’s nuclear weapons possessors ever putting down such tools without rock-solid assurances that no one else will take them up?
There are no shortcuts to nuclear disarmament. Unrealistic attempts to skip to the finish line have the potential to undermine the institutions and standards we have worked so hard to build. Our collective experience demonstrates that inclusiveness and the search for consensus can lead to progress, while polarization is a recipe for failure. We urge all states to work with us in searching for common solutions to collective problems, pursuing a more secure world.
As ondas de ultrassom são muito utilizadas em um exame denominado ultrassonografia (USG). O exame é realizado passando-se um transdutor que emite uma onda de ultrassom, com frequências entre 1 MHz e 10 MHz, numa velocidade das ondas de ultrassom nos tecidos humanos da ordem de 1500m/s, que é refletida pelo órgão de acordo com sua densidade, sendo captado a onda refletida enviada ao computador que forma as imagens em função da densidade do órgão estudado.
Com base no exposto a respeito do ultrassom, analise as proposições a seguir, marque com V as verdadeiras e com F as falsas e assinale a alternativa com a sequência correta.
( ) O comprimento de onda dessas ondas de ultrassom nesse exame varia de 1,5mm a 0,15mm.
( ) A realização do diagnóstico por imagem tem como base os fenômenos de reflexão e refração de ondas longitudinais.
( ) Também por ser uma onda pode-se usar o efeito Doppler para avaliar a velocidade do fluxo sanguíneo, por exemplo.
( ) O ultrassom é uma onda eletromagnética, por esse fato pode penetrar nos órgãos e tecidos.
( ) O exame é comum para acompanhar as gestações, pois não utiliza radiações ionizantes.
OMS alerta para falta de novos antibióticos e pede mais investimentos
Organização Mundial da Saúde (OMS) alertou sobre a "séria escassez" de novos antibióticos para combater bactérias cada vez mais resistentes, e defendeu redobrar os investimentos diante desta "crescente ameaça" à saúde mundial. A tuberculose resistente, a cada ano mata 250 mil pessoas no planeta. A OMS publicou em fevereiro uma lista de 12 famílias de "superbactérias", contra as quais considera urgente desenvolver novos medicamentos, a exemplo de enterobactérias como Klebsiella e E.coli.
Fonte: g1.globo, 22/09/2017 (Adaptado) Disponível em: http://g1.globo.com.br
Considerando as informações contidas no texto e os conhecimentos relacionados ao tema é correto afirmar, exceto:
Text
A French art expert believes a charcoal drawing kept in a collection for more than 150 years may be a preparatory sketch made by Leonardo da Vinci of the Mona Lisa.
The black-and-white drawing of a woman, nude from the waist up, known as the Monna Vanna, was previously attributed to Leonardo’s studio, suggesting it was done in his style by a pupil or follower, not by the master himself.
But after preliminary tests at the Louvre Museum, experts believe the sketch may well have been drawn by Leonardo.
Among the signs, according to curator Mathieu Deldicque, are the fact the drawing was made during the same period as the Mona Lisa, the paper is from the same region of Italy, and the technique is very similar to that of the Mona Lisa.
“We know the drawing was made during the lifetime of Leonardo da Vinci, we know that the paper was made in Italy, between Venice and Florence, and the third discovery is the high quality of this drawing in the face of the Monna Vanna and in her arms,” Deldicque told reporters.
“That’s very interesting because the arms are the same as the Mona Lisa‘s.”
Leonardo, who lived from 1452 to 1519, was an engineer, scientist, inventor and sculptor, as well as one of the finest artists of the Italian Renaissance.
He painted the Mona Lisa, also known as La Gioconda and regarded as the world’s most valuable artwork, at the beginning of the 16th century. It is believed to depict Lisa Gherardini, the wife of a successful merchant.
EXCITING
The charcoal portrait, in which the woman is holding a similar pose to the Mona Lisa but with her body more side-on and her head turned further over her left shoulder, has been held in a collection at the Conde Museum at the Palace of Chantilly, north of Paris, since 1862.
The Mona Lisa and Monna Vanna hold their hands in very similar ways, the right hand across the left and resting on the forearm, the fingers gently extended.
Deldicque said that while it was exciting to think the charcoal drawing was created by Leonardo, there were more tests to be done.
“We have one more month of analysis and then a very slow process of history of art with a collection of analysts and advice by specialists,” he said.
It is possible that process will determine that the authorship is the same. But it may also be inconclusive, he said, adding:
“Maybe the mystery will remain.”
(Source: adapted from http://www.reuters.com/article/us-france-monalisa-sketch/is-16th-century-charcoal-sketch-a-naked-mona-lisa-idUSKCN1C42LD, retrieved on October 1, 2017)
No século XVII, Marcello Malpighi iniciou uma série de estudos microscópicos com diferentes tecidos animais, porém, o termo histologia só foi utilizado pela primeira vez em 1819 por Mayer. Histologia é o estudo dos tecidos biológicos e dos tecidos plasmáticos de animais e plantas, sua formação, estrutura e função.
Em relação aos tecidos animais, correlacione as colunas a seguir e assinale a alternativa com a sequência correta.
( 1 ) Tecido Epitelial
( 2 ) Tecido Conjuntivo
( 3 ) Tecido Muscular
( 4 ) Tecido Nervoso
( 5 ) Tecido Hematopoiético
( ) Formado por células de origem ectodérmica altamente especializadas,
muito vascularizado e com pouca matriz extracelular.
( ) Possui células perfeitamente justapostas, com pouquíssimo espaço intercelular e, por isso, não é vascularizado, nutrindo-se por difusão a partir dos capilares existentes em outro tecido adjacente a ele.
( ) Formado por células de origem mesodérmica, que durante a diferenciação celular tornam-se longas e acumulam em seu citoplasma um grande número de fibrilas e de íons Ca++ e Mg++, fundamentais à fisiologia desse tecido.
( ) Possui origem mesodérmica, especialmente do mesênquima, e é constituído por diversos tipos celulares, fibras e substância fundamental. Sua principal função é fornecer sustentação e preencher espaços entre os tecidos, além de nutri-los.
( ) Também denominado tecido reticular, formado por fibras e células indiferenciadas pluripotentes.