Este blogger apoia Israel: fez o que toda nação soberana deve sempre fazer

Ao contrário da decisão do atual governo brasileiro condenando Israel, este blogger apoia irrestritamente a ação israelense contra a flotilha que se dirigia à Faixa de Gaza, e o seu direito de existir como Estado soberano.

Support Israel/Apoie Israel

Por, para e com Israel, sempre!

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COMUNICADO À IMPRENSA

31 de maio de 2010

Enviamos abaixo as reações oficiais do governo de Israel acerca dos eventos ocorridos nesta madrugada entre as Forças de Defesa de Israel (FDI) e a flotilha que seguia em direção à Faixa de Gaza.

1. Atividades e declarações do Ministro das Relações Exteriores de Israel, Avigdor Liberman

O Ministro das Relações Exteriores de Israel, Avigdor Liberman, segue conduzindo uma série de diálogos com Chanceleres de vários países e informou nesta manhã em Israel que os membros da embarcação não estavam em missão de paz e são, na verdade, terroristas que atacaram os militares das FDI quando estes abordaram a embarcação que se dirigia à Faixa de Gaza.

O Chanceler também explicou que todas as tentativas de Israel para dialogar e alcançar um entendimento com os organizadores da flotilha foram rejeitadas. Lembrou também que todas as solicitações de Israel ao Hamas para que fosse autorizada a entrada da Cruz Vermelha na Faixa de Gaza, com o fim de visitar e atender o soldado israelense seqüestrado, Gilad Shalit, foram negadas. O que aconteceu nesta manhã foi uma violência pré-planejada pelo grupo que atacou as FDI e Israel não permitirá qualquer ofensiva ao seu Estado por parte de grupos terroristas ou seus apoiadores.

2. Reação do Vice-Ministro das Relações Exteriores de Israel, Danny Ayalon.

O Vice-Ministro das Relações Exteriores de Israel, Danny Ayalon, informou nesta manhã em Israel, durante uma coletiva de imprensa, que “a armada de ódio e violência em apoio à organização terrorista Hamas foi uma provocação premeditada e ultrajante”. Os organizadores da flotilha são bem conhecidos por suas ligações com o Jihad, Al-Qaeda e o Hamas, tendo em sua trajetória um histórico de contrabando de armas e outros materiais bélicos. Ayalon informou ainda que “a bordo do navio, foram encontradas armas que estavam preparadas com antecedência e usadas contra as FDI. A intenção dos organizadores era a utilização de métodos violentos e, infelizmente, houve fortes resultados”.

Ayalon também informou que a chamada ajuda humanitária não tinha uma finalidade pacífica e se assim fosse, os organizadores teriam aceitado a oferta israelense em realizar a entrega dos materiais através dos canais apropriados, como a ONU ou a Cruz Vermelha. Na verdade, o grupo afirmou repetidas vezes que a intenção era romper o bloqueio marítimo em Gaza. Este bloqueio, realizado por Israel, é legal e justificado, levando em consideração o terror imposto pelo Hamas em Gaza. Permitir que esses navios entrassem de forma ilegal no território teria aberto um corredor de contrabando de armas e terroristas na Faixa de Gaza, resultando em morte de milhares de civis e a disseminação da violência em toda a área.

Após os repetidos avisos aos organizadores de que não seria permitido romper o bloqueio e de acordo com a lei marítima, Israel impôs o seu direito. Infelizmente os membros da flotilha não atenderam nenhuma das propostas israelenses, incluído a de hoje pela manhã, onde as FDI solicitaram que a flotilha os acompanhasse, encerrando de forma pacífica este evento.

Nenhum país soberano iria tolerar este tipo de violência contra sua população civil, contra a sua soberania, contra a lei internacional. Israel lamenta as vítimas e informa que foram usadas todas as opções e alternativas para evitar esta situação.

Informações Adicionais (em inglês)

1. Clique aqui e veja um vídeo onde membros da flotilha utilizam de alta violência contra os soldados israelenses durante a embarcação destes no navio. O evento ocorreu nesta manhã.

2. Clique aqui e acesse um documento que aponta ligações do grupo IHH (Insani Yardim Vakfi, IHH, “Fundo de Ajuda Humanitária”) com os grupos terroristas Hamas, Irmandade Mulçumana e Al-Qaeda.

3. Clique aqui e veja um vídeo onde um soldado israelense é atacado com golpes de pé-de-cabra.

4. Clique aqui e veja um vídeo onde as Forças de Defesa de Israel abordam a embarcação que se aproxima da Faixa de Gaza e oferecem o Porto em Ashdod como alternativa para que a flotilha desembarque os suprimentos e estes sejam transportados por via terrestre à Faixa de Gaza sob supervisão. A opção de transporte via terrestre é a mais segura, haja visto que algumas embarcações que supostamente levam suprimentos à Faixa de Gaza, transportam também armamentos e outros materiais bélicos. No vídeo, claramente vê-se que a embarcação recusa a proposta. Após a recusa, a flotilha atacou as FDI.

5. Clique aqui e assista um vídeo, feito antes dos recentes acontecimentos, onde os organizadores da flotilha admitem utilizar a força caso os soldados israelenses embarquem em algum navio da flotilha.

6. Clique aqui e acesse o documento “The Gaza flotilla and the maritime blockade of Gaza -- Legal background”, com informações acerca da legalidade do bloqueio marítimo em Gaza.

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Assessoria de Imprensa

Embaixada de Israel

SES Av. das Nações Qd. 809 Lote 38

CEP: 70424-900 – Brasília/DF – Brasil

Tel: (61) 2105-0529 / 2105-0505

Fax: (61) 2105-0555

E-mail: hasbara@brasilia.mfa.gov.il

Website: http://brasilia.mfa.gov.il

Fonte: Comunicado Oficial da Embaixada de Israel Sobre o Ataque à Flotilha de Ajuda Humanitária que ia para Gaza | Política Externa Brasileira

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NOTA DESTE BLOGGER:

Sou sionista, mas as minhas posições políticas não refletem a posição de neutralidade política do NBDI - Núcleo Brasileiro de Design Inteligente, Campinas, SP.

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Três subsets de sequência de complexidade e sua relevância para informação biopolimérica

Theor Biol Med Model. 2005; 2: 29.
Published online 2005 August 11. doi: 10.1186/1742-4682-2-29.
PMCID: PMC1208958

Copyright © 2005 Abel and Trevors; licensee BioMed Central Ltd.

Three subsets of sequence complexity and their relevance to biopolymeric information

David L Abel1 and Jack T Trevors2

1Director, The Gene Emergence Project, The Origin-of-Life Foundation, Inc., 113 Hedgewood Dr., Greenbelt, MD 20770-1610 USA

2Professor, Department of Environmental Biology, University of Guelph, Rm 3220 Bovey Building, Guelph, Ontario, N1G 2W1, Canada

Corresponding author.

David L Abel: life@us.net; Jack T Trevors: jtrevors@uoguelph.ca

Received May 23, 2005; Accepted August 11, 2005.

This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Image not related to this article/Imagem não relacionada com este artigo.

California Institute for Quantitative Biosciences

Genetic algorithms instruct sophisticated biological organization. Three qualitative kinds of sequence complexity exist: random (RSC), ordered (OSC), and functional (FSC). FSC alone provides algorithmic instruction. Random and Ordered Sequence Complexities lie at opposite ends of the same bi-directional sequence complexity vector. Randomness in sequence space is defined by a lack of Kolmogorov algorithmic compressibility. A sequence is compressible because it contains redundant order and patterns. Law-like cause-and-effect determinism produces highly compressible order. Such forced ordering precludes both information retention and freedom of selection so critical to algorithmic programming and control. Functional Sequence Complexity requires this added programming dimension of uncoerced selection at successive decision nodes in the string. Shannon information theory measures the relative degrees of RSC and OSC. Shannon information theory cannot measure FSC. FSC is invariably associated with all forms of complex biofunction, including biochemical pathways, cycles, positive and negative feedback regulation, and homeostatic metabolism. The algorithmic programming of FSC, not merely its aperiodicity, accounts for biological organization. No empirical evidence exists of either RSC of OSC ever having produced a single instance of sophisticated biological organization. Organization invariably manifests FSC rather than successive random events (RSC) or low-informational self-ordering phenomena (OSC).

Keywords: Self-organization, self-assembly, self-ordering, self-replication, genetic code origin, genetic information, self-catalysis.

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FREE PDF GRÁTIS

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NOTA DESTE BLOGGER:

Prestem muita, bastante atenção neste conceito -- Functional sequence complexity.

Ele vai dar muito o que falar em biologia evolutiva.

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Como que as baleias 'evoluíram' em 35 milhões de anos?

How Whales Have Changed Over 35 Million Years

ScienceDaily (May 31, 2010) — Whales are remarkably diverse, with 84 living species of dramatically different sizes and more than 400 other species that have gone extinct, including some that lived partly on land. Why are there so many whale species, with so much diversity in body size?

Humpback whale. (Credit: iStockphoto/Josh Friedman)

To answer that, UCLA evolutionary biologists and a colleague used molecular and computational techniques to look back 35 million years, when the ancestor of all living whales appeared, to analyze the evolutionary tempo of modern whale species and probe how fast whales changed their shape and body size. They have provided the first test of an old idea about why whales show such rich diversity.

"Whales represent the most spectacularly successful invasion of oceans by a mammalian lineage," said Michael Alfaro, UCLA assistant professor of ecology and evolutionary biology, and senior author of the new study, which was published this month in the early online edition ofProceedings of the Royal Society B and will appear at a later date in the journal's print edition. "They are often at the top of the food chain and are major players in whatever ecosystem they are in. They are the biggest animals that have ever lived. Cetaceans (which include whales, as well as dolphins and porpoises) are the mammals that can go to the deepest depths in the oceans.

"Biologists have debated whether some key evolutionary feature early in their history allowed whales to rapidly expand in number and form," Alfaro said. "Sonar, large brains, baleen (a structure found in the largest species for filtering small animals from sea water) and complex sociality have all been suggested as triggers for a diversification, or radiation, of this group that has been assumed to be rapid. However, the tempo -- the actual rate of the unfolding of the cetacean radiation -- has never been critically examined before. Our study is the first to test the idea that evolution in early whales was explosively fast."

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Read more here/Leia mais aqui: Science Daily

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Proceedings of the Royal Society B

Diversity versus disparity and the radiation of modern cetaceans

Graham J. Slater1,*†, Samantha A. Price2,*†‡, Francesco Santini1 and Michael E. Alfaro1

-Author Affiliations

1Department of Ecology and Evolutionary Biology, University of California at Los Angeles, Los Angeles, CA 90025, USA

2National Evolutionary Synthesis Center (NESCent), 2024 West Main Street, Suite A200, Erwin Mills Building, Durham, NC 27705, USA

*Authors for correspondence (gslater@ucla.edu; saprice@ucdavis.edu).

Abstract

Modern whales are frequently described as an adaptive radiation spurred by either the evolution of various key innovations (such as baleen or echolocation) or ecological opportunity following the demise of archaic whales. Recent analyses of diversification rate shifts on molecular phylogenies raise doubts about this interpretation since they find no evidence of increased speciation rates during the early evolution of modern taxa. However, one of the central predictions of ecological adaptive radiation is rapid phenotypic diversification, and the tempo of phenotypic evolution has yet to be quantified in cetaceans. Using a time-calibrated molecular phylogeny of extant cetaceans and a morphological dataset on size, we find evidence that cetacean lineages partitioned size niches early in the evolutionary history of neocetes and that changes in cetacean size are consistent with shifts in dietary strategy. We conclude that the signature of adaptive radiations may be retained within morphological traits even after equilibrium diversity has been reached and high extinction or fluctuations in net diversification have erased any signature of an early burst of diversification in the structure of the phylogeny.

adaptive radiation     body size    Cetacea    disparity   diversity

Footnotes

↵† These authors contributed equally to this work and should be considered joint first authors.

↵‡ Present address: Department of Evolution and Ecology, University of California at Davis, Davis, CA 95616, USA.

Received February 26, 2010.
Accepted April 30, 2010.

© 2010 The Royal Society

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O lado 'maligno' da ciência contra a humanidade: Golfo do México 2010

A ciência não é somente benéfica para a humanidade como trombeteia a Nomenklatura científica e a Grande Mídia: suas descobertas também trazem malefícios para a humanidade. Quem já se esqueceu das bombas atômicas lançadas sobre Hiroshima e Nagasaki no século 20? Se já se esqueceram, eis aqui uma lembrança recente de que avanços científicos têm efeitos negativos e destruidores contra a humanidade...

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Um presidente 'democrata' apoiando um ditador: pior do que isso, só isso!

29/05/2010
Brasil ao lado do Irã: pior, impossível

The New York Times

Thomas L. Friedman

Luiz Inácio Lula da Silva cumprimenta o presidente iraniano Mahmoud Ahmadinejad, em Teerã

Eu confesso que, quando vi pela primeira vez a foto de 17 de maio do presidente do Irã, Mahmoud Ahmadinejad, ao lado de seu par brasileiro, Luiz Inácio Lula da Silva, e do primeiro-ministro da Turquia, Recep Tayyip Erdogan, com os braços levantados –após assinarem um suposto acordo para neutralizar a crise em torno do programa de armas nucleares do Irã– tudo o que pude pensar foi: existe algo pior do que ver democratas traírem outros democratas para um criminoso iraniano, ladrão de votos, negador do Holocausto, apenas para importunar os Estados Unidos e mostrar que eles também podem jogar na mesa das grandes potências?

Não, pior impossível.

“Por anos, os países não alinhados e em desenvolvimento acusaram os Estados Unidos de buscarem cinicamente seus próprios interesses sem consideração pelos direitos humanos”, observou Karim Sadjadpour, do Fundo Carnegie. “Ao aspirarem jogar no palco global, Turquia e Brasil irão enfrentar as mesmas críticas que antes faziam aos outros. A visita de Lula e Erdogan ao Irã ocorreu poucos dias após o Irã ter executado cinco presos políticos que foram torturados para obtenção de confissões. Eles abraçaram calorosamente Ahmadinejad como sendo seu irmão, mas não mencionaram nenhuma palavra sobre direitos humanos. Parece haver uma noção equivocada de que os palestinos são as únicas pessoas que buscam justiça no Oriente Médio e que, se você invocar a causa deles, pode mimar a tipos como Ahmadinejad.”

Turquia e Brasil são ambos democracias nascentes que superaram suas próprias histórias de governo militar. O fato de seus líderes aceitarem e fortalecerem um presidente iraniano que usa seu exército e sua polícia para esmagar e matar democratas iranianos –pessoas que buscam a mesma liberdade de expressão e de escolha política que turcos e brasileiros agora desfrutam– é vergonhoso.

“Lula é um gigante político, mas moralmente ele tem sido uma profunda decepção”, disse Moisés Naím, editor-chefe da revista “Foreign Policy” e ex-ministro do Comércio da Venezuela.

Lula, como notou Naím, “apoiou a sabotagem da democracia na América Latina". Ele frequentemente elogia o homem forte da Venezuela, Hugo Chávez, e Fidel Castro, o ditador cubano –e agora Ahmadinejad– enquanto condena a Colômbia, uma das grandes histórias de sucesso democrático, porque o país permite que os aviões dos Estados Unidos usem campos de aviação colombianos para combater os narcotraficantes. “Lula tem sido ótimo para o Brasil, mas terrível para seus vizinhos democráticos”, disse Naím. O Lula que ganhou proeminência como um líder operário progressista no Brasil virou as costas aos líderes operários violentamente reprimidos do Irã.

Claro que se o Brasil e a Turquia tivessem realmente persuadido os iranianos a abandonar de forma comprovada todo o seu suposto programa de armas nucleares, os Estados Unidos certamente teriam apoiado. Mas não foi isso o que aconteceu.
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Acesso integral ao texto somente para assinantes da Folha de São Paulo/UOL

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Ferramentas de comparação genômica são passíveis de erros

Genome Comparison Tools Found to Be Susceptible to Slip-Ups

ScienceDaily (May 29, 2010) — You might call it comparing apples and oranges, but lining up different species' genomes is common practice in evolutionary research. Scientists can see how species have evolved, pinpoint which sections of DNA are similar between species, meaning they probably are crucial to the animals' survival, or sketch out evolutionary trees in places where the fossil record is spotty.

But the tools used to align genomes from different species have serious quality-control issues, according to a study published online this week in the journal Nature Biotechnology.

"We discovered that there's a disturbingly low level of agreement between genome alignments produced by different tools," said corresponding author Martin Tompa, a UW professor of computer science and engineering and of genome sciences. "What this should suggest to biologists is that they should be very cautious about trusting these alignments in their entirety."

Nature Biotechnology

This is especially true when comparing distantly related species, and in regions of the genome that do not code for a protein, he said.

Aligning genomes, while simple in theory, is difficult in practice. Aligning more than two sequences becomes much harder with every additional sequence. At the scale of a mammal's entire genome, all of its genetic code, finding the optimal alignment of many genomes is far beyond the capabilities of any computer, Tompa said.

Various software tools instead use strategic shortcuts.

"At a high level the tools are very similar," Tompa said. "They make different decisions at the lower, more detailed levels, and those decisions seem to have widespread effect on the outcome."

The new paper compared the alignments from a previous study in which four research teams each took the same 1 percent of the human genome and aligned it to the genomes of 27 other vertebrate animals, ranging from mouse to elephant.

"This is a marvelous dataset," Tompa said. "It's a very large-scale multiple sequence alignment, done by four expert teams using four different tools, all of them working on the same input sequences."

However, the new study found that the resulting alignments were quite different. The authors also compared the coverage of each tool, meaning how much of the human DNA it was able to match to each other species, as well as what fraction of alignments were suspiciously close to a random match.

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Read more here/Leia mais aqui: Science Daily

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Comparative assessment of methods for aligning multiple genome sequences

Xiaoyu Chen & Martin Tompa

Affiliations

Contributions

Corresponding authorNature Biotechnology (2010) doi:10.1038/nbt.1637Received 21 December 2009 Accepted 27 April 2010 Published online 23 May 2010

Abstract

Multiple sequence alignment is a difficult computational problem. There have been compelling pleas for methods to assess whole-genome multiple sequence alignments and compare the alignments produced by different tools. We assess the four ENCODE alignments, each of which aligns 28 vertebrates on 554 Mbp of total input sequence. We measure the level of agreement among the alignments and compare their coverage and accuracy. We find a disturbing lack of agreement among the alignments not only in species distant from human, but even in mouse, a well-studied model organism. Overall, the assessment shows that Pecan produces the most accurate or nearly most accurate alignment in all species and genomic location categories, while still providing coverage comparable to or better than that of the other alignments in the placental mammals. Our assessment reveals that constructing accurate whole-genome multiple sequence alignments remains a significant challenge, particularly for noncoding regions and distantly related species.

Affiliations

Department of Computer Science and Engineering, Department of Genome Sciences, University of Washington, Seattle, Washington, USA.
Xiaoyu Chen & Martin Tompa

Contributions

X.C., design, implementation, experimentation, analysis; M.T., design, analysis.

Competing financial interests

The authors declare no competing financial interests.

Corresponding author

Correspondence to:
Martin Tompa (tompa@cs.washington.edu)

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A explosão de estrelas estilhaçou o espelho da vida?

Did exploding stars shatter life's mirror?

19 May 2010 by Marcus Chown

Magazine issue 2760.

Explosive twist (Image: Robert Mallozz/Marshall Space Flight Center)

MR SPOCK is dying. Fortunately for the crew of the USS Enterprise, the Spock in question is not the real one, but an evil mirror-image version created in a freak transporter malfunction. This Spock's back-to-front body can digest only right-handed amino acids; meanwhile, like all organic matter, the food around him is made of left-handed amino acids. He is starving in the midst of plenty.

This plot line from the 1970 novel Spock Must Die! - the first literary spin-off from the Star Trek TV series - highlights one of life's fundamental mysteries. Why does biology use only one of two mirror-image forms in which most complex molecules can occur? The latest pop at an answer weaves astrophysics, particle physics and biochemistry into a startling proposal: that the stellar explosions known as supernovae are to blame.

"It is an intriguing idea," says Daniel Glavin, an astrobiologist at the NASA Goddard Flight Center in Greenbelt, Maryland. It is certainly a novel turn in this twistiest of tales: the story of how life came to be left-handed.

The property of handedness, known to chemists as chirality, is a feature of many molecules whose arrangement of atoms is not completely symmetrical. A chiral molecule comes in two forms that are rather like a pair of gloves. Right and left-handed gloves are essentially identical, with the same basic components, four fingers and a thumb, and the same function of keeping our hands snug and protected. They are not exactly the same, however: you cannot rotate or flip a glove of one type so that it will superimpose perfectly on the other. But look in a mirror, and a left-handed glove becomes right-handed.

Similar molecular mirror-image forms are called enantiomers. They are made from the same atoms and have the same chemical and physical properties. Most chemical reactions produce equal quantities of both.

That makes nature's predilection for one form - its "homochirality" - all the more strange. Only left-handed or "l" amino acids make up the proteins that provide our cells with structure and regulate their functions, and only right-handed or "d" sugars play an active part in biochemistry. It is like keeping a drawer full of only one sort of glove, while stubbornly refusing to wear the other.

Star turn

Perhaps homochirality is the result of a chance asymmetry in life's early history on Earth, amplified by time and evolution. In that case, you might expect it to be non-existent or even reversed elsewhere. Yet the builder's rubble left over from the construction of the solar system tells a different story. "For every type of amino acid found in meteorites there is an excess of the left-handed form over the right-handed of between 2 and 18 per cent," says Uwe Meierhenrich of the Nice Sophia Antipolis University in France. "An excess of the right-handed form has never been found."

That alone does not prove anything: meteorites might have become contaminated when they came into contact with the Earth's surface and before they were picked up. But the strong implication is that the left-handed bias pre-dates the existence of life, our planet and indeed our solar system, even if life on Earth amplified it to an extreme.

So is the asymmetry simply a question of basic physics? That is certainly a possibility (see "Disturbance in the force"), but there are other attractive suggestions too. One was identified in 1998, when a team led by Jeremy Bailey of the University of New South Wales in Sydney, Australia, discovered regions in the Orion nebula, a star-forming zone 1300 light years away from Earth, that are suffused with circularly polarised infrared light (Science, vol 281, p 672).

Light becomes circularly polarised when its associated electric field vibrates in a plane that rotates clockwise or anticlockwise about its direction of travel. In a nebula, such polarisation could happen when light is scattered off the atoms and molecules, including amino acids, floating around in the gas clouds.

Circularly polarised light interferes with the arrangement of electrons that bind atoms together in such a way that it can selectively break up molecules of one or other chiral form, depending on which way it is rotating. The regions of the Orion nebula identified by Bailey and his colleagues could therefore have an excess of one form of amino acid. A similar situation in the cloud from which our solar system formed could have been the chiral seed from which asymmetric life on Earth grew.

It is a seductive possibility, but it has its problems. The selective destruction of amino acids only kicks in if the light has enough energy to trigger the necessary chemical reactions - in practice requiring the presence of ultraviolet light, rather than the less energetic infrared light seen in the Orion nebula. "No one has detected any of this light yet," says Meierhenrich - although this might be because the gas clouds scatter ultraviolet light so effectively that little of it makes it to our telescopes.

The new scenario sketched by Richard Boyd of the National Ignition Facility in Livermore, California, along with Toshitaka Kajino and Takashi Onaka of the University of Tokyo, Japan, sidesteps this problem. It too starts with a cloud in which molecules, including amino acids, have already formed. But light is not the catalyst for change; instead, it is the combined effect of the immense magnetic fields and the vast fluxes of high-energy particles that are produced in a supernova explosion.

A core-collapse, or type II, supernova occurs when a massive star, its fuel spent, collapses within seconds under its own weight to form a superdense neutron star just tens of kilometres across. This remnant generates an incredibly intense magnetic field, with field lines emerging from its north pole and returning to its south pole, as is the case with Earth's magnetic field.

Atomic nuclei have a quantum-mechanical property known as spin which, all things being equal, aligns itself with a magnetic field. The crux of Boyd's idea is the effect such magnetic fields have on nitrogen-14 nuclei in an amino acid, where a nitrogen atom attaches the defining amine (NH2) group to a carboxyl group. Within a molecule, nitrogen spins do not have the latitude of movement they would if they were free, and calculations performed by the chemist A. D. Buckingham of the University of Cambridge in 2004 show how switching on a magnetic field in fact produces a rotational effect in different directions for molecules of opposite chiralities (Chemical Physics Letters, vol 398, p 1).

As a result, Boyd suggests, when the magnetic field of a supernova remnant starts up, amino acids of one chirality end up with their nitrogen spins pointing along the magnetic field lines, away from the star at the north pole and towards it at the south, while those of the opposite chirality will be forced to align with their nitrogen spins in the opposing direction.

This sets the stage for fireworks as the dying star collapses in on itself, sending an intense blast of neutrinos and antineutrinos spewing out radially in all directions, including along the magnetic field lines. Antineutrinos in particular react readily with nitrogen-14 nuclei, producing a carbon-14 nucleus and a positron. In a similar, energetically less-favoured reaction, neutrinos turn nitrogen-14 into oxygen-14 and an electron. In both cases, once the nitrogen nucleus in an amino acid is hit, the amine group is blown apart and the amino acid disintegrates.

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Read more here/Leia mais aqui: New Scientist

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John Wheeler 'falou e disse': os cientistas são ignorantes sobre muitas coisas

“Nós não sabemos a primeira coisa sobre o universo, sobre nós mesmos, e sobre o nosso lugar no universo.” - John Wheeler (1911-2008)

Cover: John Archibald Wheeler (1911–2008) had a lasting impact not just on the many areas of physics he explored but also on the physicists he mentored and inspired during his long career. In this special issue, which includes reprints of two pieces Wheeler wrote for PHYSICS TODAY, we pay tribute to his contributions and legacy. (Photo courtesy of the AIP Emilio Segrè Visual Archives, Wheeler Collection.)

“We do not know the first thing about the universe, about ourselves, and about our place in the universe.” 

- John Wheeler

Physics Today special issue on John Wheeler/Edição especial da Physics Today sobre John Wheeler

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Rizoma: um novo modelo de evolução

Um novo modelo para evolução: um rizoma

Sábado, 29 de maio de 2010

Os evolucionistas têm um problema. A teoria deles não se encaixa com os fatos, mas mesmo assim deve ser verdade. Constantemente eles têm de mudar sua teoria, e ao mesmo tempo insistindo que ela é um fato. Como um fluxo heracliteano, ela está mudando constantemente, e mesmo assim sempre chamada da mesma coisa. Os evolucionistas são surpreendidos continuamente pel ciência, mas eles chamam isso eufemisticamente de “progresso.” Um artigo recente publicado na The Lancet, sugerindo que a evolução é como um rizoma, é um bom exemplo tão óbvio da loucura da evolução.

“In 2009, with the 200th anniversary of Darwin's birthday, the concept of Darwinism became so popular that it was celebrated in most biological journals. However, the Darwinist theory of evolution is associated with the scientific knowledge and outdated beliefs of the 19th century. The theory is characterised by a description of life as a tree in which all living organisms are thought to have a single ancestor and where each node represents a common ancestor (Darwin's tree) … The structure of our current knowledge base has changed substantially. …”

“Em 2009, com os 200 anos do aniversário do nascimento de Darwin, o conceito de darwinismo se tornou tão popular que isso foi celebrado na maioria dos journals biológicos. Todavia, a teoria darwinista de evolução está associada com o conhecimento científico e crenças superadas do século 19. A teoria é caracterizada por uma descrição da vida como uma árvore na qual todos os organismos vivos são considerados como tendo um único ancestral comum e onde cada nódulo representa um ancestral comum (a árvore de Darwin) … A estrutura de nossa base atual de conhecimento tem mudado substancialmente. …”

Darwin tinha certeza de que Deus não teria criado um padrão de hierarquia aninhada que as espécies foram consideradas como formando. Hoje nós sabemos que aquele padrão é um modelo bruto e inexato.

“In the 21st century, the genomic revolution has brought about an important change in the way we think about life, which has forced us to reconsider the way we describe evolution. Genomic data have gradually accumulated and show that there were multiple original sources of the genetic information of living organisms, with inheritance occurring not only vertically but also laterally. Such lateral gene transfer, initially observed only in bacteria, was quickly identified in all living organisms. For example, the human genome is a mosaic of genes with eukaryotic, bacterial (in the mitochondria and the nucleus), and viral origins. …”

“No século 21, a revolução genômica trouxe uma importante mudança no modo como nós pensamos sobre a vida, que tem nos forçado a reconsiderar a maneira como nós descrevemos a evolução. Os dados genômicos têm se acumulado gradualmente e mostram que houve fontes múltiplas de origem da informação genética dos orgnismos vivos, com a herança ocorrendo não somente verticalmente mas também lateralmente. Tal mudança lateral de gene, observada inicialmente somente em bactérias, foi rapidamente identificada em todos os organismos vivos. Por exemplo, o genoma humano é um mosaico de genes com origens eucarióticas, bacterianas (na mitocôndria e no núcleo), e viral. …”

Múltiplas origens, vertical, lateral, gradual, puntiliar, para trás, para frente. Entendeu?

“Thus we cannot currently identify a single common ancestor for the gene repertoire of any organism. Comparative genome analysis shows not only a substantial level of plasticity in the gene repertoire, but also provides evidence that nearly all genes, including ribosomal genes, have been exchanged or recombined at some point in time. Overall, it is now thought that there are no two genes that have a similar history along the phylogenic tree.”

“Assim, nós não podemos atualmente identificar um único ancestral comum para o repertório de gene de qualquer organismo. A análise comparativa de genomas mostra não apenas um nível substancial de plasticidade no repertório de genes, mas também fornece evidência de que aproximadamente todos os genes, inclusive os genes ribosomais, foram trocados ou recombinados em algum ponto no tempo. Além disso, agora é aceito que não existem dois genes que tenham uma história similar ao longo da árvore filogênica.”

Então, por que nós precisamos novamente de um dogma do século 19?

“Moreover, there are some genes that do not have a single history, due to the occurrence of intragenic recombinations. Therefore the representation of the evolutionary pathway as a tree leading to a single common ancestor on the basis of the analysis of one or more genes provides an incorrect representation of the stability and hierarchy of evolution. Finally, genome analyses have revealed that a very high proportion of genes are likely to be newly created through gene fusion, degradation, or other events, and that some genes are only found in one organism (named ORFans). These genes do not belong to any phylogenic tree and represent new genetic creations.”

“Além disso, existem alguns genes que não têm um só história, devido à ocorrência de recombinações intragênicas. Portanto, a representação de um caminho evolucionário como uma árvore levando a um único ancestral comum na base da análise de um ou mais genes fornece uma incorreta representação da estabilidade e hierarquia da evolução. Finalmente, as analyses de genomes têm revelado que uma proporção muito alta de genes são prováveis de serem recém-criados através da fusão de gene, degradação, ou outros eventos, e que alguns genes são somente encontrados em um organismo (chamados de ORFans). Estes genes não pertencem a nenhuma árvore filogenética e representam novas criações genéticas.”

Quando os evolucionistas afirmam que os genes que aparecem de lugar nenhum “são prováveis de serem recém-criados através da fusão de gene, degradação, ou outros eventos,” eles querem dizer o oposto de ter evoluído pela narrativa convencional de descendência comum, ou via transferência horizontal de gene. Aquelas avenidas são descartadas, assim o evolucionista deve lançar mão de esquemas improváveis. Ele então os rotula como “prováveis” não porque a ciência e a matemática revelem que isso seja assim, mas porque a evolução tem que ser verdade.

“A post-Darwinist concept of the living species can be proposed, to integrate the theories of multiplicity and de-novo creation … I believe that the evolution of species looks much more like a rhizome (or a mycelium). Consequently, this view of evolution resembles a clump of roots that considers the occurrence of multiplicities. Emerging species grow from the rhizome with gene repertoires of various origins that will allow, under favourable environmental conditions, the multiplication and perpetuation of this species. As such, potential new species and new genes arecontinuously appearing.”

“Um conceito pós-darwinista de species vivas pode ser proposto, para integrar as teorias de multiplicidade e criação de-novo… Eu acredito que a evolução das espécies se parece muito mais como um rizoma (ou um micélio). Consequentemente, esta visão da evolução se parece com um clump de raízes que considera a ocorrência de multiplicidades. As species que surgem crescem a partir do rizoma com um repertório de genes de várias origens que irá permitir, sob condições ambientais favoráveis, a multiplicação e a perpetuação desta espécie. Como tal, novas species e novo genes potenciais estão continuamente aparecendo.”

Um bom exemplo de como o pensamento evolucionário faz deboche da ciência.

“I suggest we respect the revolutionary mind of Darwin and allow the theory of evolution itself to evolve from a tree to a rhizome.”

“Eu sugiro que nós respeitemos a mente revolucionária de Darwin e permitamos que a própria teoria da evolução evolua de uma árvore para um rizoma.”

Não existe muito o que respeitar. Darwin não foi um intelectual revolucionário. O forte levantamento teológico e filosófico foi feito muito antes de Darwin embarcar em um navio e ir a lugar nenhum. Darwin tinha um bom domínio da ciência, mas a virou de cabeça para baixo para se encaixar com a metafísica daquele tempo.

Postado por Cornelius Hunter Sábado, 29 de maio de 2010 

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The Lancet

Volume 375, Issue 9709, 9 January 2010-15 January 2010, Pages 104-105

No abstract/Sem abstract

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Professores, pesquisadores e alunos de universidades públicas e privadas com acesso ao site CAPES/Periódicos podem ler gratuitamente este artigo do The Lancet e de mais 22.440 publicações científicas. 

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NOTA CAUSTICANTE DESTE BLOGGER:

A Árvore da Vida de Darwin era uma miragem epistêmica que iludiu a muitos renomados cientistas nestes 150 anos de biologia evolutiva. Gente, como é que mentes tão brilhantes assim foram enganadas cientificamente por tanto tempo? E como é que fica agora as dissertações de mestrado e teses de doutorados em biologia evolutiva e em outras áreas cientificas em que a Árvore da Vida de Darwin foi o sujeito da pesquisa? Revogar os diplomas de mestrados e doutorados? E a grade curricular? A abordagem da evolução nos livros didáticos de Biologia do ensino médio aprovados pelo MEC/SEMTEC/PNLEM?

Árvore da Vida de Darwin, gente, KAPUT -- está mais para um gramado de vida e sem origem darwiniana. É ruim, hein, ma é vero! Que venga logo la nueva teoría de evolución -- a SÍNTESE EVOLUTIVA AMPLIADA que por estas razões acima, e mais uma montanha de evidências contrárias, não pode e nem deve ser selecionista. Quem viver, verá. A Nomenklatura científica já se deu ao luxo de fixar uma década como o tempo necessário para a elaboração desta nova teoria geral da evolução. Será selecionista? A menos que agora CIÊNCIA e MENTIRA andem de mãos dadas...

Fui, nem sei por que, rindo gostosamente da cara da Galera dos meninos e meninas de Darwin e de muitos na Nomenklatura científica, especialmente os agentes da KGB, oops revisores por pares [peer-reviewers é très chic, chérie, très chic] que podam novas ideias científicas de serem publicadas ou apresentadas à comunidade científica. Eles ganham para isso: blindar Darwin de quaisquer críticas. Mesmo as científicas...

Aprendam: o cientista segue as evidências aonde elas forem dar.

Darwin morreu, gente!!! Viva Darwin, gente!!!

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O novo livro de Steve Fuller: The Art of Living [A Arte de Viver]

SCIENCE

Series: The Art of Living

Author(s): Steve Fuller 

ISBN: 1844652041

ISBN-13: 9781844652044

Publication Date: 31/05/2010

Pages: 176 (216 x 138mm)

Format: PaperbackPublished 

Price: £9.99Discount Price: £7.99

DESCRIPTION:

In this challenging and provocative book, Steve Fuller contends that our continuing faith in science in the face of its actual history is best understood as the secular residue of a religiously inspired belief in divine providence. Our faith in science is the promise of a life as it shall be, as science will make it one day. Just as men once put their faith in God’s activity in the world, so we now travel to a land promised by science. In Science, Fuller suggests that the two destinations might be the same one.

Fuller sympathetically explores what it might mean to live “scientifically”. Can science give a sense of completeness to one’s life? Can it account for the entirety of what it is to be human? And what does our continuing belief in scientific progress say about us as a species? In answering these questions, Fuller ranges widely over the history of science and religion – from Aristotle and the atomists to Dawkins and the neo-Darwinists – and takes a close look at what science is, how its purpose has changed over the years, and what role religion and in more recent years atheism have played in its progression.

Science, argues Fuller, is now undergoing its own version of secularization. We are ceasing to trust science in its institutional forms, formulated by an anointed class of science priests, and instead we are witnessing the emergence of what Fuller calls “Protscience” – all sorts of people, from the New Age movement to anti-evolutionists, claiming scientific authority as their own. Fuller shows that these groups are no more anti-scientific than Protestant sects were atheistic.

Fearless and thought-provoking, Science questions some of our most fundamental beliefs about the nature and role of science, and is a distinct and important contribution to debates about evolution, intelligent design, atheism, humanism, the notion of scientific progress, and the public understanding of science.

AUTHOR BIO:

Steve Fuller is Professor of Sociology at the University of Warwick.

CONTENTS:

Introduction
1. The gospel according to Dr Strangelove
2. Can science live with its past?
3. Styles of living scientifically: a tale of three nations
4. We are all scientists now: the rise of protscience
5. The scientific ethic and the spirit of literalism
6. What has atheism – old or new – ever done for science?
7. Science as an instrument of divine justice
8. Scientific progress as secular providence
9. Science poised between changing the future and undoing the past 

Further reading

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Source/Fonte: Acumen Publishing

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Primeiro dinossauro 'chifrudo' do México

First Horned Dinosaur from Mexico: Plant-Eater Had Largest Horns of Any Dinosaur

ScienceDaily (May 28, 2010) — A new species of horned dinosaur unearthed in Mexico has larger horns that any other species -- up to 4 feet long -- and has given scientists fresh insights into the ancient history of western North America, according to a research team led by paleontologists from the Utah Museum of Natural History at the University of Utah.

This is a fleshed-out artist's rendering of the Mexican horned dinosaur Coahuilaceratops.

(Credit: Lukas Panzarin for the Utah Museum of Natural History)

"We know very little about the dinosaurs of Mexico, and this find increases immeasurably our knowledge of the dinosaurs living in Mexico during the Late Cretaceous," said Mark Loewen, a paleontologist with the Utah Museum of Natural History and lead author of the study.

The 72-million-year-old rhino-sized creature -- Coahuilaceratops magnacuerna -- was a four- to five-ton plant-eater belonging to a group called horned dinosaurs, or ceratopsids. The nameCoahuilaceratops magnacuerna(Koh-WHE-lah-SARA-tops mag-NAH-KWER-na), refers to the Mexican state of Coahuila where it was found, and to the Greek word "ceratops" meaning "horned face." The second part of the name, magnacuerna, is a combination of Latin and Spanish meaning "great horn," in reference to the huge horns above the eyes of this dinosaur.

The study, partially funded by the National Geographic Society, was conducted by Mark Loewen, Scott Sampson, Eric Lund and Mike Getty, paleontologists at the Utah Museum of Natural History. Also involved were Andrew Farke of the Raymond M. Alf Museum in Claremont, Calif.; Martha Aguillón-Martínez, Claudio de Leon and Rubén Rodríguez-de la Rosa from the Museum of the Desert in Saltillo, Mexico; and David Eberth of the Royal Tyrrell Museum of Palaeontology in Alberta, Canada.

The new species is to be announced in the book "New Perspectives on Horned Dinosaurs" to be released next week by Indiana University Press.

...

Read more here/Leia mais aqui: Science Daily

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Francisco Ayala 'falou e disse': a religião não tem nada a ver com a ciência e vice-versa

Religion has nothing to do with science – and vice versa

Scientists like Richard Dawkins say the universe has no design, no purpose, no evil and no good, but these things are not the business of science, says geneticist Francisco J. Ayala. They are the exclusive preserve of religion.

By the same token, religion should not make assertions about the natural world that are contrary to science. Photograph: Max Rossi/Reuters

Are religion and science incompatible?

Some scientists assert that valid knowledge can only come from science. They hold that religious beliefs are the remains of pre-scientific explanations of the world and amount to nothing more than superstition.

On the other side, some people of faith believe that science conveys a materialistic view of the world that denies the existence of any reality outside the material world. Science, they think, is incompatible with their religious faith.

I contend that both – scientists denying religion and believers rejecting science – are wrong. Science and religious beliefs need not be in contradiction. If they are properly understood, they cannot be in contradiction because science and religion concern different matters.

The scope of science is the world of nature: the reality that is observed, directly or indirectly, by our senses. Science advances explanations about the natural world, explanations that are accepted or rejected by observation and experiment.

Outside the world of nature, however, science has no authority, no statements to make, no business whatsoever taking one position or another. Science has nothing decisive to say about values, whether economic, aesthetic or moral; nothing to say about the meaning of life or its purpose.

Science has nothing to say, either, about religious beliefs, except when these beliefs transcend the proper scope of religion and make assertions about the natural world that contradict scientific knowledge. Such statements cannot be true.

People of faith need not be troubled that science is materialistic. The materialism of science asserts its limits, not its universality. The methods and scope of science remain within the world of matter. It cannot make assertions beyond that world.

Science transcends cultural, political and religious beliefs because it has nothing to say about these subjects. That science is not constrained by cultural or religious differences is one of its great virtues. It does not transcend these differences by denying them or taking one position rather than another. It transcends cultural, political and religious convictions because these matters are none of its business.

Some scientists deny that there can be valid knowledge about values or about the meaning and purpose of the world and of human life. The biologist Richard Dawkins explicitly denies design, purpose and values.

In River out of Eden, he writes:


"The universe that we observe has precisely the properties we should expect if there is, at bottom, no design, no purpose, no evil and no good, nothing but blind, pitiless indifference."

William Provine, a historian of science, asserts that there are no absolute principles of any sort. He believes modern science directly implies that there are no inherent moral or ethical laws, no absolute guiding principles for human society.

There is a monumental contradiction in these assertions. If its commitment to naturalism does not allow science to derive values, meaning or purposes from scientific knowledge, it surely does not allow it, either, to deny their existence.

In its publication Teaching About Evolution and the Nature of Science, [1] the US National Academy of Sciences emphatically asserts that religion and science answer different questions about the world:

"Whether there is a purpose to the universe or a purpose for human existence are not questions for science."

The academy adds:

"Consequently, many people including many scientists, hold strong religious beliefs and simultaneously accept the occurrence of evolution."

Science as a mode of inquiry into the nature of the universe has been immensely successful and of great technological and economic consequence. The US Office of Management and Budget has estimated that 50% of all economic growth in the US since the second world war can be directly attributed to scientific knowledge and technical advances.

The technology derived from scientific knowledge pervades our lives: the high-rise buildings of our cities, throughways and long-span bridges, rockets that take men and women into outer space, telephones that provide instant communication across continents, computers that perform complex calculations in millionths of a second, vaccines and drugs that keep pathogens at bay, gene therapies that replace DNA in defective cells.

These remarkable achievements bear witness to the validity of the scientific knowledge from which they originated.

People of faith should stand in awe of the wondrous achievements of science. But they should not be troubled that science may deny their religious beliefs.

Nor should people of faith transgress the proper boundaries of religion by making assertions about the natural world that are contrary to scientific knowledge. Religion concerns the meaning and purpose of the world and human life, the proper relation of people to their Creator and to each other, the moral values that inspire and govern their lives.

Science, on the other hand, concerns the processes that account for the natural world: how the planets move, the composition of matter and the atmosphere, the origin and function of organisms.

Religion has nothing definitive to say about these natural processes: nothing about the causes of tsunamis or earthquakes or why volcanic eruptions occur, or why there are droughts that ruin farmers' crops. The explanation of these processes belongs to science. It is a categorical mistake to seek their explanation in religious beliefs or sacred texts.

...

Read more here/Leia mais aqui: The Guardian

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[1] Esta e algumas outras publicações da National Academy Press podem ser baixadas gratuitamente para habitantes do Terceiro Mundo e de países emergentes como o Brazil. Basta inscrever-se. 2.8 MB

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O livro "Science & Religion" descobre o que os cientistas pensam realmente sobre a religião

RELIGION

"Science vs. Religion" discovers what scientists really think about religion

Sunday, May 30, 2010

SCIENCE VS. RELIGION

What Scientists Really Think

By Elaine Howard Ecklund

Oxford Univ. 228 pp. $27.95

Americans are almost evenly divided between those who feel science conflicts with religion and those who don't. Both sides have scientific backers. Biologist Richard Dawkins rallies atheists by arguing that science renders religious faith unnecessary and irrational. Geneticist Francis S. Collins (before becoming NIH director) organized evangelical scientists to offer a vision of science and faith reinforcing each other.

Rice University sociologist Elaine Ecklund offers a fresh perspective on this debate in "Science vs. Religion." Rather than offering another polemic, she builds on a detailed survey of almost 1,700 scientists at elite American research universities -- the most comprehensive such study to date. These surveys and 275 lengthy follow-up interviews reveal that scientists often practice a closeted faith. They worry how their peers would react to learning about their religious views.

Fully half of these top scientists are religious. Only five of the 275 interviewees actively oppose religion. Even among the third who are atheists, many consider themselves "spiritual." One describes this spiritual atheism as being rooted in "wonder about the complexity and the majesty of existence," a sentiment many nonscientists -- religious or not -- would recognize. By not engaging with religion more fully and publicly, "the academy is really doing itself a big disservice," worries one scientist. As shown by conflicts over everything from evolution to stem cells to climate policy, breakdowns in communication between scientists and religious communities cause real problems, especially for scientists trying to educate increasingly religious college students.

...

Read more here/Leia mais aqui: The Washington Post

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Elaine Howard Ecklund
University of Houston

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Richard Lewontin 'falou e disse': os biólogos devem parar de falar em 'seleção natural'...

Richard Lewontin - 2003 - University of California

Foto de Jane Scherr

Richard Lewontin 'falou e disse': "os biólogos devem parar de falar em 'seleção natural' e, em vez disso, falar em taxas diferenciais de sobrevivência e reprodução". [1]

Pior a emenda do que o soneto. Traduzindo em graúdos: os mais aptos sobrevivem e reproduzem. Quem sobrevive e reproduz? Os mais aptos sobrevivem e reproduzem. Traduzindo em miúdos: gente, isso é tautologia, e tautologia em ciência não diz nada.

O que Lewontin bem destacou? É que a seleção natural, muito embora não seja o único mecanismo evolutivo, mas segundo Darwin, o mais importante, não é assim uma Brastemp para consolidar epistemicamente a maior ideia que toda a humanidade já teve.

Quer dizer, a seleção natural já era. Kaput! Bem que o Huxley, o Hooker, o Lyell, o Mivart e até Wallace falaram: não bota a seleção natural na evolução que esculhamba! Que venga la nueva teoría de evolución que, pela montanha de evidências contrárias, não pode ser selecionista.

Lewontin, cara, eu não sei o que você fez do curso de Lógica 101 na faculdade.

[1] biologists should stop referring to “natural selection,” and instead talk about differential rates of survival and reproduction.

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NOTA CAUSTICANTE DESTE BLOGGER PARA O MEC/SEMTEC/PNLEM:

Este blogger está de olho! Em 2011, nada de livros didáticos de Biologia do ensino médio com 'seleção natural'. Lewontin disse que ela não está com nada, e que é melhor usar uma tautologia brilhante: "taxas diferenciais de sobrevivência e reprodução".

Se aparecer algum autor que ouse continuar engabelando os alunos com essa tal de seleção natural, vai levar daqui uns cocorotes e puxões de orelhas! 

Aqui neste blog, a gente mata a cobra e mostra o pau!

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USP: fã de carteirinha deste blog

USP: 3%

UFSCar: 2%

UFRGS: 1%

UFRJ: 1%

EPM [Escola Paulista de Medicina]: 1%

EDU.BR: 1%

UCSB [University of California, Santa Barbara): 1%

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Alô você que disse, tempos atrás, que eu não entraria na USP: já entrei faz tempo, cara, e olha que a turma lá é Darwinista ortodoxa, fundamentalista, xiíta, pós-modernidsta, chique e perfumada a la Dawkins, mas entrei!!! E tem a universidade pública com o maior número de acessos. Por que???

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Alô pessoal da USP:

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Alô Nomenklatura científica e Grande Mídia tupiniquins: 315.000 visitantes!

Fonte: ClustrMaps

Caracas, mano! 315.000 visitantes, e a Folha de São Paulo não me entrevista? Sniff, sniff, sniff...

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Alô Galera dos meninos e meninas de Darwin:

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Ciência: empreendimento humano, demasiadamente humano, nunca puro

PAPERBACK
9780801894213

HARDBACK 9780801894206
2010 568 pp., 1 line drawing

Visit our Spring Book Sale! 

US$30.00

Never Pure

Historical Studies of Science as if It Was Produced by People with Bodies, Situated in Time, Space, Culture, and Society, and Struggling for Credibility and Authority

Steven Shapin

Steven Shapin argues that science, for all its immense authority and power, is and always has been a human endeavor, subject to human capacities and limits. Put simply, science has never been pure. To be human is to err, and we understand science better when we recognize it as the laborious achievement of fallible, imperfect, and historically situated human beings.

Shapin's essays collected here include reflections on the historical relationships between science and common sense, between science and modernity, and between science and the moral order. They explore the relevance of physical and social settings in the making of scientific knowledge, the methods appropriate to understanding science historically, dietetics as a compelling site for historical inquiry, the identity of those who have made scientific knowledge, and the means by which science has acquired credibility and authority.

This wide—ranging and intensely interdisciplinary collection by one of the most distinguished historians and sociologists of science represents some of the leading edges of change in the scholarly understanding of science over the past several decades.Steven Shapin is the Franklin L. Ford Professor of the History of Science at Harvard, and his books include Leviathan and the Air—Pump: Hobbes, Boyle, and the Experimental Life (with Simon Schaffer), A Social History of Truth: Civility and Science in Seventeenth—Century England, and The Scientific Revolution. He has written for the New Yorker and writes regularly for the London Review of Books.

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Source/Fonte: The John Hopkins University Press

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Cientista preconceituosa

Cavalo:... Então, como uma cientista preconceituosa, você chega primeiro a uma conclusão de uma teoria, depois só ignora toda evidência que prova que você está errada?

Menina: Sim.

Cavalo: Bem, então você acredita que está sempre certa?

Menina: Bem, desde que nós não ouvimos nada que prove que nós estamos errados, a lógica dita que nós devemos estar certos.

Cavalo: Sim, mas só porque você não dá ouvidos, não significa...

Menina: La La La La La La La!

Cavalo: Eu desisto!

Menina: Viu como é fácil?

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Fui, nem sei por que, pensando na Galera dos meninos e meninas de Darwin -- age igual a esta menina preconceituosa...

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Replicação de DNA... sem vida

DNA replication... without life

27 May 2010 by Kate McAlpine

Magazine issue 2762.

THE precursor of life may have learned how to copy itself thanks to simple convection at the bottom of the ocean. Lab experiments reveal how DNA replication could have occurred in tiny pores around undersea vents.

One of the initial steps towards life was the first molecule capable of copying itself. In the open ocean of early Earth, strands of DNA and loose nucleotides would have been too diluted for replication to occur. So how did they do it?

Providing a perfect setting for life to replicate (Image: University of Delaware/JGI/DOE)

Inside many undersea hydrothermal vents, magnesium-rich rocks react with sea water. Such reactions create a heat source that could drive miniature convection currents in nearby pores in the rock, claim Christof Mast and Dieter Braun of Ludwig Maximilian University of Munich, Germany. They propose that such convection could concentrate nucleotides, strands of DNA, and polymerase, providing a setting that would promote replication.

Sea water inside pores on or near a vent's chimney may undergo thermal convection because the water at the wall of the pore closest to the vent's heat source would be warmer than the water near the furthermost wall, say Mast and Braun. If the pore contained strands of DNA, nucleotides, and polymerase they would ride upward in the warm current. The DNA strands would also be "unzipped" in the heat, splitting into two strands that each serve as templates for eventual replication.

...

Read more here/Leia mais aqui: New Scientist

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Artigos citados no texto da New Scientist:

1. Phys. Rev. Lett. 104, 188102 (2010) [4 pages]

Thermal Trap for DNA Replication

Christof B. Mast and Dieter Braun*

Systems Biophysics, Physics Department, Center for Nanoscience, Ludwig Maximilians Universität München, Amalienstrasse 54, 80799 München, Germany

Received 1 August 2009; published 7 May 2010

The hallmark of living matter is the replication of genetic molecules and their active storage against diffusion. We implement both in the simple nonequilibrium environment of a temperature gradient. Convective flow both drives the DNA replicating polymerase chain reaction while concurrent thermophoresis accumulates the replicated 143 base pair DNA in bulk solution. The time constant for accumulation is 92 s while DNA is doubled every 50 s. The experiments explore conditions in pores of hydrothermal rock which can serve as a model environment for the origin of life.

© 2010 The American Physical Society
URL:
http://link.aps.org/doi/10.1103/PhysRevLett.104.188102
DOI:
10.1103/PhysRevLett.104.188102
PACS:
87.14.gk, 87.15.R-

*dieter.braun@lmu.de

2. Journal of the American Chemical Society

Formation of Protocell-like Vesicles in a Thermal Diffusion Column

Itay Budin†§, Raphael J. Bruckner‡§ and Jack W. Szostak*§

Department of Molecular and Cellular Biology, Harvard University, Cambridge, Massachusetts 02138, Department of Genetics, Harvard Medical School, Boston, Massachusetts 02115, and Howard Hughes Medical Institute, Department of Molecular Biology, and Center for Computational and Integrative Biology, Massachusetts General Hospital, Boston, Massachusetts 02114

J. Am. Chem. Soc., 2009, 131 (28), pp 9628–9629
DOI: 10.1021/ja9029818
Publication Date (Web): June 24, 2009
Copyright © 2009 American Chemical Society
szostak@molbio.mgh.harvard.edu, †

Harvard University., ‡ Harvard Medical School., § Massachusetts General Hospital

Abstract

Many of the properties of bilayer membranes composed of simple single-chain amphiphiles seem to be well-suited for a potential role as primitive cell membranes. However, the spontaneous formation of membranes from such amphiphiles is a concentration-dependent process in which a significant critical aggregate concentration (cac) must be reached. Since most scenarios for the prebiotic synthesis of fatty acids and related amphiphiles would result in dilute solutions well below the cac, the identification of mechanisms that would lead to increased local amphiphile concentrations is an important aspect of defining reasonable conditions for the origin of cellular life. Narrow, vertically oriented channels within the mineral precipitates of hydrothermal vent towers have previously been proposed to act as natural Clusius−Dickel thermal diffusion columns, in which a strong transverse thermal gradient concentrates dilute molecules through the coupling of thermophoresis and convection. Here we experimentally demonstrate that a microcapillary acting as a thermal diffusion column can concentrate a solution of oleic acid. Upon concentration, self-assembly of large vesicles occurs in regions where the cac is exceeded. We detected vesicle formation by fluorescence microscopy of encapsulated dye cargoes, which simultaneously concentrated in our channels. Our findings suggest a novel means by which simple physical processes could have led to the spontaneous formation of cell-like structures from a dilute prebiotic reservoir.

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