Robert Hooke morreu há 321 anos

      

Robert Hooke (Freshwater, Isle of Wight, 28 July 1635 – London, 3 March 1703) was an English natural philosopher, architect and polymath.

His adult life comprised three distinct periods: as a scientific inquirer lacking money; achieving great wealth and standing through his reputation for hard work and scrupulous honesty following the great fire of 1666, and eventually becoming ill and party to jealous intellectual disputes (the latter may have contributed to his relative historical obscurity).

At one time he was simultaneously the curator of experiments of the Royal Society, a member of its council, Gresham Professor of Geometry, and Surveyor to the City of London after the Great Fire of London (in which capacity he appears to have performed more than half of all the surveys after the fire). He was also an important architect of his time – though few of his buildings now survive and some of those are generally misattributed – and was instrumental in devising a set of planning controls for London whose influence remains today. Allan Chapman has characterised him as "England's Leonardo".

Robert Gunther's Early Science in Oxford, a history of science in Oxford during the Protectorate, Restoration and Age of Enlightenment, devotes five of its fourteen volumes to Hooke.

Hooke studied at Wadham College, Oxford during the Protectorate where he became one of a tightly knit group of ardent Royalists led by John Wilkins. Here he was employed as an assistant to Thomas Willis and to Robert Boyle, for whom he built the vacuum pumps used in Boyle's gas law experiments. He built some of the earliest Gregorian telescopes and observed the rotations of Mars and Jupiter. In 1665 he inspired the use of microscopes for scientific exploration with his book, Micrographia. Based on his microscopic observations of fossils, Hooke was an early proponent of biological evolution. He investigated the phenomenon of refraction, deducing the wave theory of light, and was the first to suggest that matter expands when heated and that air is made of small particles separated by relatively large distances. He performed pioneering work in the field of surveying and map-making and was involved in the work that led to the first modern plan-form map, though his plan for London on a grid system was rejected in favour of rebuilding along the existing routes. He also came near to an experimental proof that gravity follows an inverse square law, and hypothesised that such a relation governs the motions of the planets, an idea which was independently developed by Isaac Newton. Much of Hooke's scientific work was conducted in his capacity as curator of experiments of the Royal Society, a post he held from 1662, or as part of the household of Robert Boyle.

     

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Robert Hooke morreu há 320 anos

      

Robert Hooke (Freshwater, Isle of Wight, 28 July 1635 – London, 3 March 1703) was an English natural philosopher, architect and polymath.

His adult life comprised three distinct periods: as a scientific inquirer lacking money; achieving great wealth and standing through his reputation for hard work and scrupulous honesty following the great fire of 1666, and eventually becoming ill and party to jealous intellectual disputes (the latter may have contributed to his relative historical obscurity).

At one time he was simultaneously the curator of experiments of the Royal Society, a member of its council, Gresham Professor of Geometry, and Surveyor to the City of London after the Great Fire of London (in which capacity he appears to have performed more than half of all the surveys after the fire). He was also an important architect of his time – though few of his buildings now survive and some of those are generally misattributed – and was instrumental in devising a set of planning controls for London whose influence remains today. Allan Chapman has characterised him as "England's Leonardo".

Robert Gunther's Early Science in Oxford, a history of science in Oxford during the Protectorate, Restoration and Age of Enlightenment, devotes five of its fourteen volumes to Hooke.

Hooke studied at Wadham College, Oxford during the Protectorate where he became one of a tightly knit group of ardent Royalists led by John Wilkins. Here he was employed as an assistant to Thomas Willis and to Robert Boyle, for whom he built the vacuum pumps used in Boyle's gas law experiments. He built some of the earliest Gregorian telescopes and observed the rotations of Mars and Jupiter. In 1665 he inspired the use of microscopes for scientific exploration with his book, Micrographia. Based on his microscopic observations of fossils, Hooke was an early proponent of biological evolution. He investigated the phenomenon of refraction, deducing the wave theory of light, and was the first to suggest that matter expands when heated and that air is made of small particles separated by relatively large distances. He performed pioneering work in the field of surveying and map-making and was involved in the work that led to the first modern plan-form map, though his plan for London on a grid system was rejected in favour of rebuilding along the existing routes. He also came near to an experimental proof that gravity follows an inverse square law, and hypothesised that such a relation governs the motions of the planets, an idea which was independently developed by Isaac Newton. Much of Hooke's scientific work was conducted in his capacity as curator of experiments of the Royal Society, a post he held from 1662, or as part of the household of Robert Boyle.

     

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Robert Hooke morreu há 319 anos

      

Robert Hooke (Freshwater, Isle of Wight, 28 July 1635 – London, 3 March 1703) was an English natural philosopher, architect and polymath.

His adult life comprised three distinct periods: as a scientific inquirer lacking money; achieving great wealth and standing through his reputation for hard work and scrupulous honesty following the great fire of 1666, and eventually becoming ill and party to jealous intellectual disputes (the latter may have contributed to his relative historical obscurity).

At one time he was simultaneously the curator of experiments of the Royal Society, a member of its council, Gresham Professor of Geometry, and Surveyor to the City of London after the Great Fire of London (in which capacity he appears to have performed more than half of all the surveys after the fire). He was also an important architect of his time – though few of his buildings now survive and some of those are generally misattributed – and was instrumental in devising a set of planning controls for London whose influence remains today. Allan Chapman has characterised him as "England's Leonardo".

Robert Gunther's Early Science in Oxford, a history of science in Oxford during the Protectorate, Restoration and Age of Enlightenment, devotes five of its fourteen volumes to Hooke.

Hooke studied at Wadham College, Oxford during the Protectorate where he became one of a tightly knit group of ardent Royalists led by John Wilkins. Here he was employed as an assistant to Thomas Willis and to Robert Boyle, for whom he built the vacuum pumps used in Boyle's gas law experiments. He built some of the earliest Gregorian telescopes and observed the rotations of Mars and Jupiter. In 1665 he inspired the use of microscopes for scientific exploration with his book, Micrographia. Based on his microscopic observations of fossils, Hooke was an early proponent of biological evolution. He investigated the phenomenon of refraction, deducing the wave theory of light, and was the first to suggest that matter expands when heated and that air is made of small particles separated by relatively large distances. He performed pioneering work in the field of surveying and map-making and was involved in the work that led to the first modern plan-form map, though his plan for London on a grid system was rejected in favour of rebuilding along the existing routes. He also came near to an experimental proof that gravity follows an inverse square law, and hypothesised that such a relation governs the motions of the planets, an idea which was independently developed by Isaac Newton. Much of Hooke's scientific work was conducted in his capacity as curator of experiments of the Royal Society, a post he held from 1662, or as part of the household of Robert Boyle.

     

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Robert Hooke morreu há 318 anos

   

Robert Hooke (Freshwater, Isle of Wight, 28 July 1635 – London, 3 March 1703) was an English natural philosopher, architect and polymath.

His adult life comprised three distinct periods: as a scientific inquirer lacking money; achieving great wealth and standing through his reputation for hard work and scrupulous honesty following the great fire of 1666, and eventually becoming ill and party to jealous intellectual disputes (the latter may have contributed to his relative historical obscurity).

At one time he was simultaneously the curator of experiments of the Royal Society, a member of its council, Gresham Professor of Geometry, and Surveyor to the City of London after the Great Fire of London (in which capacity he appears to have performed more than half of all the surveys after the fire). He was also an important architect of his time – though few of his buildings now survive and some of those are generally misattributed – and was instrumental in devising a set of planning controls for London whose influence remains today. Allan Chapman has characterised him as "England's Leonardo".

Robert Gunther's Early Science in Oxford, a history of science in Oxford during the Protectorate, Restoration and Age of Enlightenment, devotes five of its fourteen volumes to Hooke.

Hooke studied at Wadham College, Oxford during the Protectorate where he became one of a tightly knit group of ardent Royalists led by John Wilkins. Here he was employed as an assistant to Thomas Willis and to Robert Boyle, for whom he built the vacuum pumps used in Boyle's gas law experiments. He built some of the earliest Gregorian telescopes and observed the rotations of Mars and Jupiter. In 1665 he inspired the use of microscopes for scientific exploration with his book, Micrographia. Based on his microscopic observations of fossils, Hooke was an early proponent of biological evolution. He investigated the phenomenon of refraction, deducing the wave theory of light, and was the first to suggest that matter expands when heated and that air is made of small particles separated by relatively large distances. He performed pioneering work in the field of surveying and map-making and was involved in the work that led to the first modern plan-form map, though his plan for London on a grid system was rejected in favour of rebuilding along the existing routes. He also came near to an experimental proof that gravity follows an inverse square law, and hypothesised that such a relation governs the motions of the planets, an idea which was independently developed by Isaac Newton. Much of Hooke's scientific work was conducted in his capacity as curator of experiments of the Royal Society, a post he held from 1662, or as part of the household of Robert Boyle.

   

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O polimata Robert Hooke morreu há 315 anos

Robert Hooke (Freshwater, Isle of Wight, 28 July 1635 – London, 3 March 1703) was an English natural philosopher, architect and polymath.

His adult life comprised three distinct periods: as a scientific inquirer lacking money; achieving great wealth and standing through his reputation for hard work and scrupulous honesty following the great fire of 1666, and eventually becoming ill and party to jealous intellectual disputes (the latter may have contributed to his relative historical obscurity).

At one time he was simultaneously the curator of experiments of the Royal Society, a member of its council, Gresham Professor of Geometry, and Surveyor to the City of London after the Great Fire of London (in which capacity he appears to have performed more than half of all the surveys after the fire). He was also an important architect of his time – though few of his buildings now survive and some of those are generally misattributed – and was instrumental in devising a set of planning controls for London whose influence remains today. Allan Chapman has characterised him as "England's Leonardo".

Robert Gunther's Early Science in Oxford, a history of science in Oxford during the Protectorate, Restoration and Age of Enlightenment, devotes five of its fourteen volumes to Hooke.

Hooke studied at Wadham College, Oxford during the Protectorate where he became one of a tightly knit group of ardent Royalists led by John Wilkins. Here he was employed as an assistant to Thomas Willis and to Robert Boyle, for whom he built the vacuum pumps used in Boyle's gas law experiments. He built some of the earliest Gregorian telescopes and observed the rotations of Mars and Jupiter. In 1665 he inspired the use of microscopes for scientific exploration with his book, Micrographia. Based on his microscopic observations of fossils, Hooke was an early proponent of biological evolution. He investigated the phenomenon of refraction, deducing the wave theory of light, and was the first to suggest that matter expands when heated and that air is made of small particles separated by relatively large distances. He performed pioneering work in the field of surveying and map-making and was involved in the work that led to the first modern plan-form map, though his plan for London on a grid system was rejected in favour of rebuilding along the existing routes. He also came near to an experimental proof that gravity follows an inverse square law, and hypothesised that such a relation governs the motions of the planets, an idea which was independently developed by Isaac Newton. Much of Hooke's scientific work was conducted in his capacity as curator of experiments of the Royal Society, a post he held from 1662, or as part of the household of Robert Boyle.

  

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Welcome to the Future

Biologia: bactéria totalmente comandada por ADN sintético reproduziu-se

Nasceu a primeira forma de vida artificial 

As primeiras células sintéticas pareciam diminutos ovos estrelados azuis

Uma bactéria, comandada por uma molécula de ADN sintético, conseguiu reproduzir-se da forma mais natural. O resultado, publicado na revista Science, tem aplicações e implicações – científicas e filosóficas – ainda em grande parte desconhecidas

Na fotografia, as células, com uns 70 micrómetros de diâmetro, parecem diminutos ovos estrelados com a gema azul. Graças a isso, sabemos que não estamos a olhar para uns microrganismos quaisquer, mas para as bactérias criadas por cientistas no laboratório. Vida artificial, fabricada de raiz num pratinho de vidro, a partir dos seus componentes genéticos elementares.

A nova bactéria foi feita “a partir de quatro frascos de compostos químicos”, gosta de repetir Craig Venter nas entrevistas que tem concedido à imprensa (sob embargo) nos últimos dias. Com os seus colegas, o conhecido “caça-genes” norte-americano acaba de inaugurar oficialmente a “era da biologia sintética”. Cada um desses quatro “frascos”, entenda-se, contém uma das "letras" do "alfabeto" com que se escreve o ADN – A, T, G, C –, as moléculas de base que compõem esse grande livro da vida genético.

A equipa do J. Craig Venter Institute, EUA, já tinha anunciado várias vezes o que vinha aí. Mas na realidade, a sua saga, que começou há mais de 15 anos e custou 40 milhões de dólares, foi pautada, sobretudo desde 2007, por episódios muito excitantes – e também por obstáculos que fizeram os autores temer o fracasso. “Demorou muito mais tempo do que poderíamos ter imaginado”, salienta Venter.

Mas já está – e o nascimento desta primeira forma de vida artificial ficará registado para a posteridade nas páginas da edição de sexta-feira da revista Science (e na Web, desde hoje). “Esta é a primeira célula sintética jamais fabricada”, afirma Venter, “e dizemos que é sintética porque a célula é totalmente derivada de um cromossoma sintético.”

Peças de lego

Em 2007, a equipa mostrou que era possível transplantar o genoma de bactérias de uma espécie para bactérias de outra espécie semelhante e fazer com que a segunda mudasse de espécie, adquirindo a da primeira – isto é, trocasse a sua própria identidade pela do seu novo ADN. No ano seguinte, conseguiram sintetizar na íntegra o genoma de uma bactéria.

Bastava agora, para criar um ser vivo artificial, combinar as duas coisas. Assim obter-se-ia uma bactéria cujo ADN fora retirado e substituído por um ADN diferente – e desta vez, completamente fabricado pelos cientistas. Esperava-se que esta bactéria se comportasse como um ser vivo natural, usando o ADN sintético como património genético para se reproduzir.

Uma primeira dificuldade técnica foi simplesmente o facto de não existir tecnologia que permita construir moléculas do tamanho do ADN, composto pelo encadeamento de centenas de milhares de pares de bases A, T, G, C. Ora, o ADN da bactéria utilizada nas experiências, Mycoplasma mycoides, contém mais de um milhão de pares de bases.

Os cientistas começaram por comprar a uma empresa especializada os cerca de 1000 bocadinhos, cada um com uns 1000 pares de bases, que constituem esse ADN bacteriano. Recorda Venter: “Foi como ter uma caixa de peças de lego e ter de as montar.”

Introduziram as peças dentro de leveduras (uma máquina natural de desfiar ADN) e obtiveram peças mais extensas; a seguir, introduziram-nas dentro de bactérias Escherischia coli e sintetizaram cadeias ainda maiores – antes de as voltarem a pôr dentro de leveduras. No fim, tinham um genoma inteiro de Mycoplasma mycoides, totalmente fabricado no laboratório.

Contudo, o ADN sintético era um pouco diferente do ADN natural de Mycoplasma mycoides, porque entretanto os cientistas tinham eliminado 14 genes potencialmente patogénicos (para as cabras) e acrescentado várias “marcas de água” – sequências de letras do ADN facilmente reconhecíveis como artificiais: um sítio de Internet, os nomes dos elementos da equipa e várias citações famosas, “para dar um toque mais filósofico à coisa”, frisa Venter.

Um bug microscópico

Mas o mais difícil foi fazer com que o novo ADN funcionasse dentro das células hospedeiras – e de facto, da primeira vez que os cientistas introduziram, esperançados, o genoma sintético nas células da bactéria Mycoplasma capricolum... nada aconteceu. Tal e qual especialistas de software, a equipa andou durante três meses a fazer debugging do código do ADN, explica um artigo jornalístico que acompanha a publicação na Science. Finalmente descobriram, há cerca de um mês, que o que estava a empatar tudo era um erro numa única letra do código! Os ovos estrelados com gema azul começaram a proliferar.

Nem toda a gente concorda em dizer que a nova bactéria é totalmente sintética, uma vez que foi preciso introduzir o ADN artificial dentro de uma célula viva já existente. Mas isso não impede os especialistas ouvidos pela Science de saudarem os resultados. Venter, quanto a ele, não tem dúvidas de que a bactéria seja totalmente sintética: “Após algumas replicações, não resta absolutamente nada de M. capricolum nas novas células”, argumenta. Novas células que produzem unicamente – e da forma mais natural do mundo – proteínas específicas de M. mycoides.

Por enquanto, o processo não é eficiente. Mas as aplicações futuras podem ser coisas como a criação de algas produtoras de petróleo (Venter já tem um “grande contrato” com a Exxon) ou que reduzem “em 99 por cento” o tempo de fabrico das vacinas contra a gripe sazonal (em colaboração com a Novartis).

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