Galáxias rotativas podem provar que a matéria escura está errada???

sexta-feira, setembro 30, 2016

The Radial Acceleration Relation in Rotationally Supported Galaxies

Stacy McGaugh, Federico Lelli, Jim Schombert

(Submitted on 19 Sep 2016)

Source/Fonte: The Pinwheel Galaxy - ESA & NASA
Abstract

We report a correlation between the radial acceleration traced by rotation curves and that predicted by the observed distribution of baryons. The same relation is followed by 2693 points in 153 galaxies with very different morphologies, masses, sizes, and gas fractions. The correlation persists even when dark matter dominates. Consequently, the dark matter contribution is fully specified by that of the baryons. The observed scatter is small and largely dominated by observational uncertainties. This radial acceleration relation is tantamount to a natural law for rotating galaxies.

Comments: 6 pages, 3 figures. Accepted for publication in Physical Review Letters

Subjects: Astrophysics of Galaxies (astro-ph.GA)

Cite as: arXiv:1609.05917 [astro-ph.GA]

(or arXiv:1609.05917v1 [astro-ph.GA] for this version)

Submission history

From: Stacy McGaugh [view email

[v1] Mon, 19 Sep 2016 20:02:10 GMT (161kb,D)

FREE PDF GRATIS: arXiv 

Biologia de sistemas do proteoma estrutural

Systems biology of the structural proteome

Elizabeth Brunk†, Nathan Mih†, Jonathan Monk, Zhen Zhang, Edward J. O’Brien, Spencer E. Bliven, Ke Chen, Roger L. Chang, Philip E. Bourne and Bernhard O. PalssonEmail author

†Contributed equally

BMC Systems Biology BMC series – open, inclusive and trusted 201610:26

DOI: 10.1186/s12918-016-0271-6 © Brunk et al. 2016

Received: 17 October 2015 Accepted: 16 February 2016 Published: 11 March 2016



Abstract

Background

The success of genome-scale models (GEMs) can be attributed to the high-quality, bottom-up reconstructions of metabolic, protein synthesis, and transcriptional regulatory networks on an organism-specific basis. Such reconstructions are biochemically, genetically, and genomically structured knowledge bases that can be converted into a mathematical format to enable a myriad of computational biological studies. In recent years, genome-scale reconstructions have been extended to include protein structural information, which has opened up new vistas in systems biology research and empowered applications in structural systems biology and systems pharmacology.

Results

Here, we present the generation, application, and dissemination of genome-scale models with protein structures (GEM-PRO) for Escherichia coli and Thermotoga maritima. We show the utility of integrating molecular scale analyses with systems biology approaches by discussing several comparative analyses on the temperature dependence of growth, the distribution of protein fold families, substrate specificity, and characteristic features of whole cell proteomes. Finally, to aid in the grand challenge of big data to knowledge, we provide several explicit tutorials of how protein-related information can be linked to genome-scale models in a public GitHub repository (https://github.com/SBRG/GEMPro/tree/master/GEMPro_recon/).

Conclusions

Translating genome-scale, protein-related information to structured data in the format of a GEM provides a direct mapping of gene to gene-product to protein structure to biochemical reaction to network states to phenotypic function. Integration of molecular-level details of individual proteins, such as their physical, chemical, and structural properties, further expands the description of biochemical network-level properties, and can ultimately influence how to model and predict whole cell phenotypes as well as perform comparative systems biology approaches to study differences between organisms. GEM-PRO offers insight into the physical embodiment of an organism’s genotype, and its use in this comparative framework enables exploration of adaptive strategies for these organisms, opening the door to many new lines of research. With these provided tools, tutorials, and background, the reader will be in a position to run GEM-PRO for their own purposes.

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O que é a essência da vida? E o que é a Biologia? Ciência com sujeito desconhecido de pesquisa???

The essence of life

Wentao Ma Email author 

Biology Direct 201611:49

DOI: 10.1186/s13062-016-0150-5 © The Author(s). 2016

Received: 17 June 2016 Accepted: 8 September 2016 Published: 26 September 2016


Abstract

Although biology has achieved great successes in recent years, we have not got a clear idea on “what is life?” Actually, as explained here, the main reason for this situation is that there are two completely distinct aspects for “life”, which are usually talked about together. Indeed, in respect to these two aspects: Darwinian evolution and self-sustaining, we must split the concept of life correspondingly, for example, by defining “life form” and “living entity”, separately. For life’s implementation (related to the two aspects) in nature, three mechanisms are crucial: the replication of DNA/RNA-like polymers by residue-pairing, the sequence-dependent folding of RNA/protein-like polymers engendering special functions, and the assembly of phospholipid-like amphiphiles forming vesicles. The notion “information” is significant for us to comprehend life phenomenon: the life form of a living entity can just be defined by its genetic information; Darwinian evolution is essentially an evolution of such information, transferred across generations. The in-depth analysis concerning the essence of life would improve our cognition in the whole field of biology, and may have a direct influence on its subfields like the origin of life, artificial life and astrobiology.

Reviewers

This article was reviewed by Anthony Poole and Thomas Dandekar.

Keywords

The definition of life Darwinian entity Self-sustained system Origins of life Bioinformation

FREE PDF GRATIS: Biology Direct

A estrutura espiral local da Via Láctea

quinta-feira, setembro 29, 2016

The local spiral structure of the Milky Way

Ye Xu1,*, Mark Reid2, Thomas Dame2, Karl Menten3, Nobuyuki Sakai4, Jingjing Li1,3, Andreas Brunthaler3, Luca Moscadelli5, Bo Zhang6 and Xingwu Zheng7

- Author Affiliations

1Purple Mountain Observatory, Chinese Academy of Sciences, Nanjing 210008, China.

2Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138, USA.

3Max-Planck-Institut für Radioastronomie, Auf dem Hügel 69, 53121 Bonn, Germany.

4Mizusawa VLBI (Very Long Baseline Interferometry) Observatory, National Astronomical Observatory of Japan, Japan.

5INAF (Istituto Nazionale di Astrofisica)–Osservatorio Astrofisico di Arcetri, Largo E. Fermi 5, 50125 Firenze, Italy.

6Shanghai Astronomical Observatory, Chinese Academy of Sciences, Shanghai 200030, China.

7Nanjing University, Nanjing 210093, China.

↵*Corresponding author. Email: xuye@pmo.ac.cn

Science Advances 28 Sep 2016:

Vol. 2, no. 9, e1600878



Abstract

The nature of the spiral structure of the Milky Way has long been debated. Only in the last decade have astronomers been able to accurately measure distances to a substantial number of high-mass star-forming regions, the classic tracers of spiral structure in galaxies. We report distance measurements at radio wavelengths using the Very Long Baseline Array for eight regions of massive star formation near the Local spiral arm of the Milky Way. Combined with previous measurements, these observations reveal that the Local Arm is larger than previously thought, and both its pitch angle and star formation rate are comparable to those of the Galaxy’s major spiral arms, such as Sagittarius and Perseus. Toward the constellation Cygnus, sources in the Local Arm extend for a great distance along our line of sight and roughly along the solar orbit. Because of this orientation, these sources cluster both on the sky and in velocity to form the complex and long enigmatic Cygnus X region. We also identify a spur that branches between the Local and Sagittarius spiral arms.

Key words Masers high angular resolution astrometry star formation galaxy spiral arm

Copyright © 2016, The Authors

This is an open-access article distributed under the terms of the Creative Commons Attribution-NonCommercial license, which permits use, distribution, and reproduction in any medium, so long as the resultant use is not for commercial advantage and provided the original work is properly cited.

FREE PDF GRATIS: Science Advances

Epigenética e o metabolismo celular

Epigenetics and Cellular Metabolism

Wenyi Xu, Fengzhong Wang, Zhongsheng Yu and Fengjiao Xin

Genetics & Epigenetics 2016:8 43-51

Review Published on 25 Sep 2016 DOI: 10.4137/GEG.S32160

Further metadata provided in PDF


Abstract

Living eukaryotic systems evolve delicate cellular mechanisms for responding to various environmental signals. Among them, epigenetic machinery (DNA methylation, histone modifications, microRNAs, etc.) is the hub in transducing external stimuli into transcriptional response. Emerging evidence reveals the concept that epigenetic signatures are essential for the proper maintenance of cellular metabolism. On the other hand, the metabolite, a main environmental input, can also influence the processing of epigenetic memory. Here, we summarize the recent research progress in the epigenetic regulation of cellular metabolism and discuss how the dysfunction of epigenetic machineries influences the development of metabolic disorders such as diabetes and obesity; then, we focus on discussing the notion that manipulating metabolites, the fuel of cell metabolism, can function as a strategy for interfering epigenetic machinery and its related disease progression as well.

FREE PDF GRATIS: Genetics and Epigenetics

O epigenoma: o próximo substrato de engenharia epigenômica

The epigenome: the next substrate for engineering

Minhee Park, Albert J. Keung and Ahmad S. KhalilEmail author

Genome Biology 201617:183

DOI: 10.1186/s13059-016-1046-5 © The Author(s). 2016

Published: 31 August 2016


Abstract

We are entering an era of epigenome engineering. The precision manipulation of chromatin and epigenetic modifications provides new ways to interrogate their influence on genome and cell function and to harness these changes for applications. We review the design and state of epigenome editing tools, highlighting the unique regulatory properties afforded by these systems.

FREE PDF GRATIS: Genome Biology

Pesquisas de G-quadruplexos formados dentro de mini círculos de DNA automontados

Studies of G-quadruplexes formed within self-assembled DNA mini-circles

Ramon Vilar, Beata Klejevskaja, Alice Pyne, Matthew T Reynolds, Arun Shivalingam, Richard Thorogate, Bart Hogenboom and Liming Ying 

Chem. Commun., 2016, Accepted Manuscript


Received 30 Aug 2016, Accepted 22 Sep 2016

First published online 23 Sep 2016 This article is licensed under a Creative Commons Attribution-NonCommercial 3.0 Unported Licence.



Abstract

We have developed self-assembled DNA mini-circles that contain a G-quadruplex-forming sequence from the c-Myc oncogene promoter and demonstrate by FRET that the G-quadruplex unfolding kinetics are 10-fold slower than for the simpler 24-mer G-quadruplex that is commonly used for FRET experiments.

Nova teoria da origem da vida: Quimeras RNA-DNA no contexto de uma transição do Mundo RNA para um Mundo RNA/DNA

RNA–DNA Chimeras in the Context of an RNA World Transition to an RNA/DNA World

Authors

Dr. Jesse V. Gavette, Dr. Matthias Stoop, Prof. Nicholas V. Hud, Prof. Ramanarayanan Krishnamurthy

First published: 21 September 2016




Abstract

The RNA world hypothesis posits that DNA and proteins were later inventions of early life, or the chemistry that gave rise to life. Most scenarios put forth for the emergence of DNA assume a clean separation of RNA and DNA polymer, and a smooth transition between RNA and DNA. However, based on the reality of “clutter” and lack of sophisticated separation/discrimination mechanisms in a protobiological (and/or prebiological) world, heterogeneous RNA–DNA backbone containing chimeric sequences could have been common—and have not been fully considered in models transitioning from an RNA world to an RNA–DNA world. Herein we show that there is a significant decrease in Watson–Crick duplex stability of the heterogeneous backbone chimeric duplexes that would impede base-pair mediated interactions (and functions). These results point to the difficulties for the transition from one homogeneous system (RNA) to another (RNA/DNA) in an RNA world with a heterogeneous mixture of ribo- and deoxyribonucleotides and sequences, while suggesting an alternative scenario of prebiological accumulation and co-evolution of homogeneous systems (RNA and DNA).

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Pouca evidência no contexto de justificação teórica desmistifica a hipótese do exito evolucionário dos peixes teleósteos!!!

quarta-feira, setembro 28, 2016

Little evidence for enhanced phenotypic evolution in early teleosts relative to their living fossil sister group

John T. Clarke a,b,1, Graeme T. Lloyd c, and Matt Friedman b,2

Author Affiliations

aDepartment of Earth and Environmental Science, University of Pennsylvania, Philadelphia, PA 19104-6316;

bDepartment of Earth Sciences, University of Oxford, Oxford OX1 3AN, United Kingdom;

cDepartment of Biological Sciences, Faculty of Science, Macquarie University, North Ryde, NSW 2109, Australia

Edited by Neil H. Shubin, University of Chicago, Chicago, IL, and approved August 19, 2016 (received for review May 6, 2016)



Significance

The success of teleost fishes, which represent roughly half of all vertebrate species, has attracted attention since Darwin. Numerous scenarios invoke elevated diversification in teleosts facilitated by supposed key innovations, yet claims of teleost exceptionalism are profoundly biased by the evolutionary “snapshot” of living fishes. Analysis of 160 million y (Permian–Early Cretaceous) of evolution in neopterygian fishes reveals that anatomical diversification in Mesozoic teleosts as a whole differed little from their “living fossil” holostean sister group. There is some evidence for evolutionary heterogeneity within teleosts, with early evolving lineages showing the greatest capacity for evolutionary innovation in body shape among Mesozoic neopterygians, whereas members of the modern teleost radiation show higher rates of shape evolution.

Abstract

Since Darwin, biologists have been struck by the extraordinary diversity of teleost fishes, particularly in contrast to their closest “living fossil” holostean relatives. Hypothesized drivers of teleost success include innovations in jaw mechanics, reproductive biology and, particularly at present, genomic architecture, yet all scenarios presuppose enhanced phenotypic diversification in teleosts. We test this key assumption by quantifying evolutionary rate and capacity for innovation in size and shape for the first 160 million y (Permian–Early Cretaceous) of evolution in neopterygian fishes (the more extensive clade containing teleosts and holosteans). We find that early teleosts do not show enhanced phenotypic evolution relative to holosteans. Instead, holostean rates and innovation often match or can even exceed those of stem-, crown-, and total-group teleosts, belying the living fossil reputation of their extant representatives. In addition, we find some evidence for heterogeneity within the teleost lineage. Although stem teleosts excel at discovering new body shapes, early crown-group taxa commonly display higher rates of shape evolution. However, the latter reflects low rates of shape evolution in stem teleosts relative to all other neopterygian taxa, rather than an exceptional feature of early crown teleosts. These results complement those emerging from studies of both extant teleosts as a whole and their sublineages, which generally fail to detect an association between genome duplication and significant shifts in rates of lineage diversification.

neopterygian phylogeny genome duplication fossil record morphological diversification

Footnotes

1To whom correspondence should be addressed. Email: j.clarke.paleo@gmail.com.

2Present address: Museum of Paleontology and Department of Earth and Environmental Science, University of Michigan, Ann Arbor, MI 48108-1079.

Author contributions: J.T.C. and M.F. designed research; J.T.C. performed research; G.T.L. contributed new reagents/analytic tools; J.T.C. and G.T.L. analyzed data; and J.T.C., G.T.L., and M.F. wrote the paper.

The authors declare no conflict of interest.

This article is a PNAS Direct Submission.

This article contains supporting information online at www.pnas.org/lookup/suppl/doi:10.1073/pnas.1607237113/-/DCSupplemental.

Freely available online through the PNAS open access option.

FREE PDF GRATIS: PNAS

Sequências de proteínas encontradas em casca de ovo de avestruz de 3.8 milhões de anos???

terça-feira, setembro 27, 2016

Protein sequences bound to mineral surfaces persist into deep time

Beatrice Demarchi Shaun Hall Teresa Roncal-Herrero Colin L Freeman Jos Woolley Molly K Crisp Julie Wilson Anna Fotakis Roman Fischer Benedikt M Kessler Rosa Rakownikow Jersie-Christensen Jesper V Olsen James Haile Jessica Thomas Curtis W Marean John Parkington Samantha Presslee Julia Lee-Thorp Peter Ditchfield Jacqueline F Hamilton Martyn W Ward Chunting Michelle Wang Marvin D Shaw Terry Harrison Manuel Domínguez-Rodrigo Ross DE MacPhee Amandus Kwekason Michaela Ecker Liora Kolska Horwitz Michael Chazan Roland Kröger Jane Thomas-Oates John H Harding Enrico Cappellini Kirsty Penkman Matthew J Collins 

University of York, United Kingdom; University of Sheffield, United Kingdom; University of Copenhagen, Denmark; University of Oxford, United Kingdom; Bangor University, United Kingdom; Arizona State University, United States; Nelson Mandela Metropolitan University, South Africa; University of Cape Town, South Africa; New York University, United States; Complutense University of Madrid, Spain; American Museum of Natural History, United States; National Museum of Tanzania, Tanzania; The Hebrew University, Israel; University of Toronto, Canada; University of the Witwatersrand, South Africa; Centre of Excellence in Mass Spectrometry, University of York, United States


Published September 27, 2016

Cite as eLife 2016;5:e17092


Eggshell peptide sequences from Africa have thermal ages two orders of magnitude older than those reported for DNA or bone collagen.
(A) Sites reporting the oldest DNA and collagen sequences are from high latitude sites compared to ostrich eggshell samples from sites in Africa illustrated in (B) for which the current mean annual air temperatures are much higher. (C) Kinetic estimates of rates of decay for DNA (Lindahl and Nyberg, 1972), collagen (Buckley and Collins, 2011) and ostrich eggshell proteins (Crisp et al., 2013) were used to estimate thermal age assuming a constant 10°C (Figure 1—source data 1; Appendix 1. For Elands Bay Cave and Pinnacle Point the oldest samples are shown). Note log scale on the z-axis: struthiocalcin-1 peptide survival is two orders of magnitude greater than any previously reported sequence, offering scope for the survival of peptide sequences into deep time.


Abstract

Proteins persist longer in the fossil record than DNA, but the longevity, survival mechanisms and substrates remain contested. Here, we demonstrate the role of mineral binding in preserving the protein sequence in ostrich (Struthionidae) eggshell, including from the palaeontological sites of Laetoli (3.8 Ma) and Olduvai Gorge (1.3 Ma) in Tanzania. By tracking protein diagenesis back in time we find consistent patterns of preservation, demonstrating authenticity of the surviving sequences. Molecular dynamics simulations of struthiocalcin-1 and -2, the dominant proteins within the eggshell, reveal that distinct domains bind to the mineral surface. It is the domain with the strongest calculated binding energy to the calcite surface that is selectively preserved. Thermal age calculations demonstrate that the Laetoli and Olduvai peptides are 50 times older than any previously authenticated sequence (equivalent to ~16 Ma at a constant 10°C).


eLife digest

The pattern of chemical reactions that break down the molecules that make our bodies is still fairly mysterious. Archaeologists and geologists hope that dead organisms (or artefacts made from them) might not decay entirely, leaving behind clues to their lives. We know that some molecules are more resistant than others; for example, fats are tough and survive for a long time while DNA is degraded very rapidly. Proteins, which are made of chains of smaller molecules called amino acids, are usually sturdier than DNA. Since the amino acid sequence of a protein reflects the DNA sequence that encodes it, proteins in fossils can help researchers to reconstruct how extinct organisms are related in cases where DNA cannot be retrieved.

Time, temperature, burial environment and the chemistry of the fossil all influence how quickly a protein decays. However, it is not clear what mechanisms slow down decay so that full protein sequences can be preserved and identified after millions of years. As a result, it is difficult to know where to look for these ancient sequences.

In the womb of ostriches, several proteins are responsible for assembling the minerals that make up the ostrich eggshell. These proteins become trapped tightly within the mineral crystals themselves. In this situation, proteins can potentially be preserved over geological time. Demarchi et al. have now studied 3.8 million-year-old eggshells found close to the equator and, despite the extent to which the samples have degraded, discovered fully preserved protein sequences.

Using a computer simulation method called molecular dynamics, Demarchi et al. calculated that the protein sequences that are able to survive the longest are stabilized by strong binding to the surface of the mineral crystals. The authenticity of these sequences was tested thoroughly using a combination of several approaches that Demarchi et al. recommend using as a standard for ancient protein studies.

Overall, it appears that biominerals are an excellent source of ancient protein sequences because mineral binding ensures survival. A systematic survey of fossil biominerals from different environments is now needed to assess whether these biomolecules have the potential to act as barcodes for interpreting the evolution of organisms.


FREE PDF GRATIS: eLIFE Appendix 1, 2, 3, 4, 5

Quem disse que Darwin baniu as essências biológicas - sem as formas platônicas a evolução colapsa!

segunda-feira, setembro 26, 2016

Possible creatures

It seemed Darwin had banished biological essences – yet evolution would fail without nature’s library of Platonic forms

Andreas Wagner is a professor in the Institute of Evolutionary Biology and Environmental Studies at the University of Zurich and at the Santa Fe Institute in New Mexico. His latest book is Arrival of the Fittest: Solving Evolution’s Greatest Puzzle (2014).

Edited by Ed Lake


When it slithers through the grass, the legless glass lizard is indistinguishable from a snake. But harass it and it will perform a very un-snakelike feat. It will leave its tail behind – still wriggling – and slide away. That isn’t the only surprise the glass lizard has in store. A careful look also reveals inflexible jaws, movable eyelids, and ear openings. These are all traits that lizards display but snakes don’t. One way or another, this peculiar creature slithers between the cracks of our familiar categories.

To organise the messy diversity of a million-plus different life forms, we need to sort them into the boxes we call species. And what would be more natural than using visible traits such as legs, jaws or ears for that purpose? About a century before Charles Darwin, the systematist Carl Linnaeus did just that when he created our modern classification of life’s diversity. So did Georges Cuvier, the father of palaeontology, when he classified fossils that had been preserved through the ages.

...

READ MORE HERE/LEIA MAIS AQUI: Aeon

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Saiba mais quem é Andreas Wagner:


Andreas Wagner é professor no Instituto de Biologia Evolucionária na Universidade de Zurique, na Suíça, e Professor Externo no Instituto Santa Fe. Ele palestra pelo mundo inteiro, e é um fellow da American Association for the Advancement of Sciences. Ele reside em Zurique, Suíça.

Andreas Wagner Laboratory, University of Zurich

Fatores genéticos e ambientais são responsáveis pela variação epigenética, mas quanto exatamente?

Genetic and environmental influences interact with age and sex in shaping the human methylome

Jenny van Dongen, Michel G. Nivard, Gonneke Willemsen, Jouke-Jan Hottenga, Quinta Helmer, Conor V. Dolan, Erik A. Ehli, Gareth E. Davies, Maarten van Iterson, Charles E. Breeze, Stephan Beck, BIOS Consortium, H. Eka Suchiman, Rick Jansen, Joyce B. van Meurs, Bastiaan T. Heijmans, P. Eline Slagboom & Dorret I. Boomsma

Nature Communications 7, Article number: 11115 (2016)


Download Citation

DNA methylation Epigenomics

Received: 10 June 2015 Accepted: 23 February 2016 Published online: 07 April 2016



Estimates of DNA methylation heritability from the GRM-based approach in 2,603 individuals. From inside to outside: the most inner circular diagram displays the average methylation level at each site, the second band shows the total heritability of DNA methylation level, the third band shows the SNP heritability of DNA methylation level, and the most outer circle shows the chromosome ideograms. Colours range from dark blue (0%) to dark red (100%).

Abstract

The methylome is subject to genetic and environmental effects. Their impact may depend on sex and age, resulting in sex- and age-related physiological variation and disease susceptibility. Here we estimate the total heritability of DNA methylation levels in whole blood and estimate the variance explained by common single nucleotide polymorphisms at 411,169 sites in 2,603 individuals from twin families, to establish a catalogue of between-individual variation in DNA methylation. Heritability estimates vary across the genome (mean=19%) and interaction analyses reveal thousands of sites with sex-specific heritability as well as sites where the environmental variance increases with age. Integration with previously published data illustrates the impact of genome and environment across the lifespan at methylation sites associated with metabolic traits, smoking and ageing. These findings demonstrate that our catalogue holds valuable information on locations in the genome where methylation variation between people may reflect disease-relevant environmental exposures or genetic variation.


Acknowledgements
We thank the twins and their family members who participate in the studies of the Netherlands Twin Register. This study was funded by: BBRMI-NL-financed BIOS Consortium (NWO 184.021.007), and Genetics of Mental Illness, a lifespan approach to the genetics of childhood and adult neuropsychiatric disorders and comorbid conditions (ERC-230374). JvD is supported by ACTION. ACTION receives funding from the European Union Seventh Framework Program (FP7/2007-2013) under grant agreement no 602768. MV is supported by Royal Netherlands Academy of Science Professor Award (PAH/6635) to DIB. CB was supported by EpiTrain (EU-FP7 316758).

Author information

Author notes
Jenny van Dongen & Michel G. Nivard

These authors contributed equally to this work.
Bastiaan T. Heijmans, P. Eline Slagboom & Dorret I. Boomsma

These authors jointly supervised this work.

Affiliations
Department of Biological Psychology, VU Amsterdam, Van der Boechorststraat 1, 1081BT Amsterdam, The Netherlands
Jenny van Dongen, Michel G. Nivard, Gonneke Willemsen, Jouke-Jan Hottenga, Quinta Helmer, Conor V. Dolan, René Pool & Dorret I. Boomsma
Avera Institute for Human Genetics, 3720 W. 69th Street, Sioux Falls, South Dakota 57108, USA
Erik A. Ehli & Gareth E. Davies
Department of Molecular Epidemiology, Leiden University Medical Center, Postzone S5-P, Postbus 9600, 2300 RC Leiden, The Netherlands
Maarten van Iterson, Marian Beekman, Joris Deelen, Ruud van der Breggen, Nico Lakenberg, Matthijs Moed, René Luijk, H. Eka Suchiman, Bastiaan T. Heijmans & P. Eline Slagboom
UCL Cancer Institute, University College London, 72 Huntley Street, London WC1E 6BT, UK
Charles E. Breeze & Stephan Beck
Department of Psychiatry, VU University Medical Center, A.J. Ernststraat 1187, 1081 HL Amsterdam, The Netherlands
Rick Jansen
Department of Internal Medicine, Erasmus Medical Center, 's Gravendijkwal 230, 3015 CE Rotterdam, The Netherlands
André G. Uitterlinden, P. Mila Jhamai, Michael Verbiest, Marijn Verkerk, Jeroen van Rooij & Joyce B. van Meurs
Department of Human Genetics, Leiden University Medical Center, 2300 RC Leiden, The Netherlands
Peter A.C.’t Hoen, Martijn Vermaat & Michiel van Galen
Department of Internal Medicine and School for Cardiovascular Diseases (CARIM), Maastricht University Medical Center, 6200 MD Maastricht, The Netherlands
Marleen M.J. van Greevenbroek, Coen D.A. Stehouwer, Carla J.H. van der Kallen & Casper G. Schalkwijk
Department of Genetics, University of Groningen, University Medical Centre Groningen, 9700 RB Groningen, The Netherlands
Cisca Wijmenga, Sasha Zhernakova, Ettje F. Tigchelaar, Dasha V. Zhernakova, Patrick Deelen, Marc Jan Bonder & Lude Franke
Department of Gerontology and Geriatrics, Leiden University Medical Center, 2300 RC Leiden, The Netherlands
Diana van Heemst
Department of Neurology, Brain Center Rudolf Magnus, University Medical Center Utrecht, 3508 GA Utrecht, The Netherlands
Jan H. Veldink & Leonard H. van den Berg
Department of Genetic Epidemiology, ErasmusMC, 3000 CA Rotterdam, The Netherlands
Cornelia M. van Duijn & Aaron Isaacs
Department of Epidemiology, ErasmusMC, 3000 CA Rotterdam, The Netherlands
Bert A. Hofman
Sequence Analysis Support Core, Leiden University Medical Center, 2300 RC Leiden, The Netherlands
Hailiang Mei, Peter van’t Hof & Wibowo Arindrarto
SURFsara, 1090 GP Amsterdam, The Netherlands
Jan Bot & Irene Nooren
Genomics Coordination Center, University Medical Center Groningen, University of Groningen, 9700 RB Groningen, The Netherlands
Freerk van Dijk & Morris A. Swertz
Medical Statistics Section, Department of Medical Statistics and Bioinformatics, Leiden University Medical Center, 2300 RC Leiden, The Netherlands
Szymon M. Kielbasa & Erik W. van Zwet
Consortia
BIOS Consortium
Peter A.C.’t Hoen, René Pool, Marleen M.J. van Greevenbroek, Coen D.A. Stehouwer, Carla J.H. van der Kallen, Casper G. Schalkwijk, Cisca Wijmenga, Sasha Zhernakova, Ettje F. Tigchelaar, Marian Beekman, Joris Deelen, Diana van Heemst, Jan H. Veldink, Leonard H. van den Berg, Cornelia M. van Duijn, Bert A. Hofman, André G. Uitterlinden, P. Mila Jhamai, Michael Verbiest, Marijn Verkerk, Ruud van der Breggen, Jeroen van Rooij, Nico Lakenberg, Hailiang Mei, Jan Bot, Dasha V. Zhernakova, Peter van’t Hof, Patrick Deelen, Irene Nooren, Matthijs Moed, Martijn Vermaat, René Luijk, Marc Jan Bonder, Freerk van Dijk, Michiel van Galen, Wibowo Arindrarto, Szymon M. Kielbasa, Morris A. Swertz, Erik W. van Zwet, Aaron Isaacs & Lude Franke
Contributions
J.v.D. and M.G.N. contributed equally. B.T.H., G.W., P.E.S. and D.I.B. jointly supervised research. J.v.D., B.T.H., M.G.N., G.W., P.E.S. and D.I.B. conceived and designed the experiments. E.A.E., G.E.D., the BIOS Consortium, H.E.S., and J.B.v.M. performed the experiments. J.v.D., M.G.N. and C.B. performed statistical analysis. J.v.D., B.T.H., M.G.N., J.J.H., Q.H., C.V.D., E.A.E., M.V.I. and the BIOS consortium analysed the data. M.G.N., C.V.D., M.v.I., C.B., S.B. and the BIOS consortium contributed reagents/materials/analysis tools. J.v.D., B.T.H., M.G.N., G.W., E.A.E., G.E.D., R.J., J.B.v.M., P.E.S. and D.I.B. wrote the paper. B.T.H., P.E.S. and D.I.B. contributed equally.

Competing interests
The authors declare no competing financial interests.

Corresponding author
Correspondence to Jenny van Dongen.

Dr. Addy Pross, 'falou e disse': a Biologia e a Física não explicam a origem da vida!

domingo, setembro 25, 2016

“Apesar da opinião generalizada de que a evolução darwinista tem sido capaz de explicar o surgimento da complexidade biológica, isso não é o caso… A teoria darwinista não lida com a questão de como [a vida] foi capaz de passar a existir. A questão problemática ainda em busca de uma resposta é: Como que um sistema capaz de evoluir surgiu originalmente? … A natureza simplesmente não funciona assim! A natureza não faz espontaneamente entidades altamente organizadas… intencionais… E aqui reside exatamente o problema [da origem] da vida… não é apenas o senso comum que nos diz que entidades altamente organizadas simplesmente não surgem espontaneamente. Certas leis básicas de Física acompanhadas de probabilidade matemática] pregam o mesmo sermão – os sistemas tendem para o caos e desordem, não para a ordem e função… A Biologia e a Física parecem contraditórias, bem incompatíveis” – What is Life: How Chemistry Becomes Biology, Oxford University Press, 2012 – Dr. Addy Pross, professor de química, Universidade Ben-Gurion, Israel.

“Despite the widespread view that Darwinian Evolution has been able to explain the emergence of biological complexity that is not the case…Darwinian theory does not deal with the question how [life] was able to come into being. The troublesome question still in search of an answer is: How did a system capable of evolving come about in the first place?…Nature just doesn’t operate like that! Nature doesn’t spontaneously make highly organized…purposeful entities…And here precisely lies the [origin of] life problem…it is not just common sense that tells us that highly organized entities don’t just spontaneously come about. Certain basic laws of physics [coupled with mathematical probability] preach the same sermon – systems tend toward chaos and disorder, not toward order and function… Biology and physics seem contradictory, quite incompatible” – What is Life: How Chemistry Becomes Biology, Oxford University Press, 2012 – Dr. Addy Pross, professor of chemistry, Ben-Gurion University, Israel.

O que há por debaixo da Groenlândia???

sábado, setembro 24, 2016

Geodetic measurements reveal similarities between post–Last Glacial Maximum and present-day mass loss from the Greenland ice sheet

Shfaqat A. Khan1,*, Ingo Sasgen2, Michael Bevis3, Tonie van Dam4, Jonathan L. Bamber5, John Wahr6,†, Michael Willis7, Kurt H. Kjær8, Bert Wouters9, Veit Helm2, Beata Csatho10, Kevin Fleming11, Anders A. Bjørk8, Andy Aschwanden12, Per Knudsen1 and Peter Kuipers Munneke9

- Author Affiliations

1DTU Space, National Space Institute, Department of Geodesy, Technical University of Denmark, Kgs. Lyngby, Denmark.

2Glaciology Section, Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Bremerhaven, Germany.

3Geodetic Science, Ohio State University, Columbus, OH 43320, USA.

4Faculty of Science, Technology, and Communication, Research Unit of Engineering Sciences, University of Luxembourg, Luxembourg, Luxembourg.

5Bristol Glaciology Centre, University of Bristol, Bristol, U.K.

6Department of Physics and Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO 80309, USA.

7Department of Earth and Atmospheric Sciences, Cornell University, Ithaca, NY 14853, USA.

8Centre for GeoGenetics, Natural History Museum of Denmark, University of Copenhagen, Copenhagen, Denmark.

9Institute for Marine and Atmospheric Research Utrecht, Utrecht University, Utrecht, Netherlands.

10Department of Geology, University at Buffalo, Buffalo, NY 14260, USA.

11Centre for Early Warning Systems Helmholtz Centre Potsdam, GFZ German Research Centre for Geosciences, Potsdam, Germany.

12Geophysical Institute, University of Alaska Fairbanks, Fairbanks, AK 99775, USA.

↵*Corresponding author. Email: abbas@space.dtu.dk

↵† Deceased.

Science Advances 21 Sep 2016:

Vol. 2, no. 9, e1600931



Fig. 1 Location map.

Locations of the GNET GPS stations (red dots) and RSL observations (green dots). Black curves denote the major drainage basins numbered from 1 to 7; drainage 3 is separated into subbasins 3A and 3B (inset), the latter representing the near field of the KUAQ glacier. The yellow curve shows a reconstruction of the Iceland hot spot track (57, 58). Bathymetry is shown over the ocean and surface elevation over the land/ice (25).

Abstract

Accurate quantification of the millennial-scale mass balance of the Greenland ice sheet (GrIS) and its contribution to global sea-level rise remain challenging because of sparse in situ observations in key regions. Glacial isostatic adjustment (GIA) is the ongoing response of the solid Earth to ice and ocean load changes occurring since the Last Glacial Maximum (LGM; ~21 thousand years ago) and may be used to constrain the GrIS deglaciation history. We use data from the Greenland Global Positioning System network to directly measure GIA and estimate basin-wide mass changes since the LGM. Unpredicted, large GIA uplift rates of +12 mm/year are found in southeast Greenland. These rates are due to low upper mantle viscosity in the region, from when Greenland passed over the Iceland hot spot about 40 million years ago. This region of concentrated soft rheology has a profound influence on reconstructing the deglaciation history of Greenland. We reevaluate the evolution of the GrIS since LGM and obtain a loss of 1.5-m sea-level equivalent from the northwest and southeast. These same sectors are dominating modern mass loss. We suggest that the present destabilization of these marine-based sectors may increase sea level for centuries to come. Our new deglaciation history and GIA uplift estimates suggest that studies that use the Gravity Recovery and Climate Experiment satellite mission to infer present-day changes in the GrIS may have erroneously corrected for GIA and underestimated the mass loss by about 20 gigatons/year.

Keywords Sea level rise climate change Greenland Ice Sheet GPS glacial isostatic adjustment Last Glacial Maximum

Copyright © 2016, The Authors

This is an open-access article distributed under the terms of the Creative Commons Attribution-NonCommercial license, which permits use, distribution, and reproduction in any medium, so long as the resultant use is not for commercial advantage and provided the original work is properly cited.

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Vamos poder recriar as cores das penas fossilizadas???

Elemental characterisation of melanin in feathers via synchrotron X-ray imaging and absorption spectroscopy

Nicholas P. Edwards, Arjen van Veelen, Jennifer Anné, Phillip L. Manning, Uwe Bergmann, William I. Sellers, Victoria M. Egerton, Dimosthenis Sokaras, Roberto Alonso-Mori, Kazumasa Wakamatsu, Shosuke Ito & Roy A. Wogelius

Scientific Reports 6, Article number: 34002 (2016)


Download Citation

Analytical chemistry Biochemistry

Received: 15 June 2016 Accepted: 02 September 2016 Published online: 23 September 2016



Abstract

Melanin is a critical component of biological systems, but the exact chemistry of melanin is still imprecisely known. This is partly due to melanin’s complex heterogeneous nature and partly because many studies use synthetic analogues and/or pigments extracted from their natural biological setting, which may display important differences from endogenous pigments. Here we demonstrate how synchrotron X-ray analyses can non-destructively characterise the elements associated with melanin pigment in situ within extant feathers. Elemental imaging shows that the distributions of Ca, Cu and Zn are almost exclusively controlled by melanin pigment distribution. X-ray absorption spectroscopy demonstrates that the atomic coordination of zinc and sulfur is different within eumelanised regions compared to pheomelanised regions. This not only impacts our fundamental understanding of pigmentation in extant organisms but also provides a significant contribution to the evidence-based colour palette available for reconstructing the appearance of fossil organisms.

Acknowledgements

Funding was provided by a UK Natural Environment Research Council grant NE/J023426/1. Portions of this research were carried out at the Stanford Synchrotron Radiation Lightsource (CA, USA), a national user facility operated by Stanford University on behalf of the U.S. Department of Energy, Office of Basic Energy Sciences. Portions of this research were also carried out at Diamond Light Source (UK, allocation SP11865 and SP12948). We thank support staff at SSRL and DLS. PLM thanks the Science and Technology Facilities Council for their support (ST/M001814/1). We also thank the Live Animal Center (LAC) at The Academy of Natural Sciences of Drexel University (Philadelphia, PA, USA) and the Wild Wings Birds of Prey education and rehabilitation centre (UK) for supply of feathers from bird under their care.

Author information

Affiliations

University of Manchester, School of Earth and Environmental Sciences, Williamson Research Centre for Molecular Environmental Science, M13 9PL, UK

Nicholas P. Edwards, Arjen van Veelen, Jennifer Anné, William I. Sellers & Roy A. Wogelius

University of Manchester, School of Earth and Environmental Sciences, Interdisciplinary Centre for Ancient Life, Manchester M13 9PL, UK

Nicholas P. Edwards, Arjen van Veelen, Jennifer Anné, Phillip L. Manning, William I. Sellers, Victoria M. Egerton & Roy A. Wogelius

College of Charleston, Department of Geology and Environmental Geosciences, Charleston, SC, 29424, USA

Phillip L. Manning & Victoria M. Egerton

Stanford PULSE Institute, SLAC National Accelerator Laboratory, Menlo Park, CA, 94025, USA

Uwe Bergmann

Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Menlo Park, CA 94025, USA

Dimosthenis Sokaras

Linac Coherent Lightsource, SLAC National Accelerator Laboratory, Menlo Park, CA, 94025, USA

Roberto Alonso-Mori

Department of Chemistry, Fujita Health University, School of Health Sciences, Toyoake, Aichi 470–1192, Japan

Kazumasa Wakamatsu & Shosuke Ito

Contributions

N.P.E., A.V.V., J.A., P.L.M., U.B., W.I.S., V.M.E., D.S., R.A.-M. and R.A.W. all participated in the synchrotron analyses. N.P.E. and J.A. composed the experimental design with guidance from R.A.W. K.W and S.I. conducted the melanin identification and quantification experiments. N.P.E. processed the synchrotron image, quantitative and sulfur XAS data, created all the figures, and composed the manuscript. A.V.V. processed and fit the Zn EXAFS data. All co-authors gave critical input to the text.

Competing interests

The authors declare no competing financial interests.

Corresponding authors

Correspondence to Nicholas P. Edwards or Roy A. Wogelius.

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