sexta-feira, 31 de julho de 2009

Visual Essays por Franke James (My Green Conscience blog)

"Nature provides a free lunch, but only if we control our appetites." ~William Ruckelshaus, Business Week, 18 June 1990


quinta-feira, 30 de julho de 2009

Is Peak Oil Real? A List of Countries Past Their Peak Oil Production


Posted by Gail the Actuary
in Planet Thoughts

Only 14 of the 54 oil producing nations in the world are still increasing their oil production. The era of cheap oil is definitively over.
This is a guest post by Praveen Ghanta, known on The Oil Drum as "praveen". Praveen is an IT consultant in Atlanta, with degrees in economics and computer science. This was originally posted on Praveen's blog, at truecostblog.com.


Is peak oil real? The BP Statistical Review of World Energy provides the data needed to answer this question. Using the 2009 edition, I have compiled a list of all oil producing countries and regions in the world, along with the production status of each, ordered by year of peak production. BP groups minor producers into categories like "Other Africa", and "Other Middle East", and that notation is used here. All production numbers are quoted in thousands of barrels/day.
Country Peak Prod. 2008 Prod. % Off Peak Peak Year
United States 11297 7337 -35% 1970
Venezuela 3754 2566 -32% 1970
Libya 3357 1846 -45% 1970
Other Middle East 79 33 -58% 1970
Kuwait 3339 2784 -17% 1972
Iran 6060 4325 -29% 1974
Indonesia 1685 1004 -41% 1977
Romania 313 99 -68% 1977
Trinidad & Tobago 230 149 -35% 1978
Iraq 3489 2423 -31% 1979
Brunei 261 175 -33% 1979
Tunisia 118 89 -25% 1980
Peru 196 120 -39% 1982
Cameroon 181 84 -54% 1985
Other Europe & Eurasia 762 427 -44% 1986
Russian Federation 11484 9886 -14% 1987*
Egypt 941 722 -23% 1993
Other Asia Pacific 276 237 -14% 1993
India 774 766 -1% 1995*
Syria 596 398 -33% 1995
Gabon 365 235 -36% 1996
Argentina 890 682 -23% 1998
Colombia 838 618 -26% 1999
United Kingdom 2909 1544 -47% 1999
Rep. of Congo (Brazzaville) 266 249 -6% 1999*
Uzbekistan 191 111 -42% 1999
Australia 809 556 -31% 2000
Norway 3418 2455 -28% 2001
Oman 961 728 -24% 2001
Yemen 457 305 -33% 2002
Other S. & Cent. America 153 138 -10% 2003*
Mexico 3824 3157 -17% 2004
Malaysia 793 754 -5% 2004*
Vietnam 427 317 -26% 2004
Denmark 390 287 -26% 2004
Other Africa 75 54 -28% 2004*
Nigeria 2580 2170 -16% 2005*
Chad 173 127 -27% 2005*
Italy 127 108 -15% 2005*
Ecuador 545 514 -6% 2006*
Saudi Arabia 11114 10846 -2% 2005 / Growing
Canada 3320 3238 -2% 2007 / Growing
Algeria 2016 1993 -1% 2007 / Growing
Equatorial Guinea 368 361 -2% 2007 / Growing
China 3795 3795 - Growing
United Arab Emirates 2980 2980 - Growing
Brazil 1899 1899 - Growing
Angola 1875 1875 - Growing
Kazakhstan 1554 1554 - Growing
Qatar 1378 1378 - Growing
Azerbaijan 914 914 - Growing
Sudan 480 480 - Growing
Thailand 325 325 - Growing
Turkmenistan 205 205 - Growing
Peaked / Flat Countries Total - 49597 - 60.6% of world oil production
Growing Countries Total - 32223 - 39.4% of world oil production
Only 14 out of 54 oil producing countries and regions in the world continue to increase production, while 30 are definitely past their production peak, and the remaining 10 appear to have flat or declining production [1]. Put another way, peak oil is real in 61% of the oil producing world when weighted by production. Since 2008 capped a record run for oil prices, most countries and oil companies were trying all-out to increase production. While a handful of producers (think Iraq) might be limited by above-ground factors, the majority of producers simply couldn't do any better in 2008 [2].
The evidence of the demise of the cheap oil era has become insurmountable. In the face of the highest oil prices on record, the great majority of the world's oil producers were incapable of taking advantage and producing more oil. Many nations including the US saw their oil production peak decades ago - there simply is no turning the clock back. This list shows that we are relying on a small number of countries to keep providing cheap oil. We need to move faster to alternatives and greater energy efficiency, before the last fourteen peak as well.
* More information on these countries:
  • Russian Federation - Russia's oil production collapsed by the early 90's as the Soviet Union collapsed, but despite a decade of growth, Russia's own oil execs don't think the old peak can be surpassed.
  • India's production appeared to plateau in 1995, and has stayed within a steady range since. The EIA forecasts Indian oil production to remain flat or decline slightly in the near future.
  • Republic of Congo (Brazzaville) hit a production plateau in 1998, though current production is still very close to 1999 peak levels.
  • Other Central & South America - The remaining countries of the Americas hit a production peak in 2003, though it's still too soon to know if this will be final peak.
  • Malaysia has been on a production plateau since 1995, and the EIA projects flat or falling production.
  • Other Africa - Oil production in much of Africa is potentially impacted by above-ground constraints, so it's definitely possible that production will rise here. It will rise from a low base of only 50,000 bpd however, and may not have much impact on total world production.
  • Nigeria is impacted by domestic insurgencies in its oil-producing regions, and may be able to lift production if the political situation improves.
  • Chad's oil production history is too short to definitively identify a peak in production, but the drop-off since 2005 has been dramatic.
  • Italy has been on a production plateau for over 10 years, and it's unlikely that a mature economy is significantly under-exploiting its resource potential.
  • Ecuador's production grew rapidly until 2004, but has leveled off and declined somewhat since then.
[1] To be considered past-peak, a producer's current (2008) production has to be at least 10% less than its best year, and the best year must have occurred prior to 2005. Some countries' production has been artificially constrained by political and other non-geological considerations. But in some of these cases, it will be difficult to pass an old peak because decades of depletion have occurred since that peak. Iraq peaked in 1979, making it all the more difficult to pass that now.
[2] While OPEC maintains formal production quotas, it is widely believed that only Saudi Arabia had true spare capacity in 2008, while all other OPEC nations were producing at capacity. The truth is unclear, since OPEC nations do not provide detailed reserve statistics for their oil fields.
Total [oil company] has created its own short list of oil producers past peak, and Wikipedia has a list here.
Source: The Oil Drum


quarta-feira, 29 de julho de 2009

Velas e Carbono* Candles and Carbon

The widespread practice of misguided eco-Luddites turning off their lights for Earth Hour and burning candles as a source of light is grossly misguided and actually contributes to increased carbon dioxide emissions. [reading more here: Physical Insights]
In a society where 94 percent* of the electrical energy generated is generated using fossil fuels, ordinary citizens using electricity are not to blame for anthropogenic greenhouse gas emissions.

* Ref: Relatório Estatístico dos Consumos Energéticos 2009 da IEA http://www.iea.org/Textbase/stats/surveys/mes.pdf


Ideia entretanto também referida em Calor: Como Impedir o Planeta de Arder, de George Monbiot

Ler mais em:
Turn Up the Heat



terça-feira, 28 de julho de 2009

Como evoluiu a vagina? Vagina Evolution


Do mesmo autor da postagem anterior PZ Myers
Resumo do artigo
Em praticamente todos os seres vivos, à excepção dos Mamíferos, o sistema reprodutor combinado com o sistema digestivo e urinário, desembocam todos num único tubo com contacto para o exterior, a cloaca. Há cerca de 150 milhões de anos, contudo, uma provável alteração nas funções do oviducto (aparecimento do útero, com funções de desenvolvimento interno do embrião) devido, muito provavelmente, a modificações epigenéticas, terá levado ao aparecimento de toda uma nova estrutura: a vagina.

Evolution of the mammalian vagina [originalmente aqui]
Q: What unique organ is found only in mammals, but not in fish, amphibians, reptiles, or birds?
The title and that little picture to the left ought to be hint enough, but if not, read on.
A: The vagina. Aren't we lucky?
There's an old joke going around about poor design: what kind of designer would route the sewer pipes right through the center of the entertainment center? It's a good point. It doesn't make sense from a design standpoint to have our reproductive and excretory systems so intimately intermingled, but it does make a heck of a lot of sense from a purely historical point of view. In a sense, reproduction is an excretory function: we are shedding gametes produced internally, and we already have a perfectly good set of pipes running from our insides to the outside, so why not use them? It's just that in our lineage, which has specialized in giving great care to our gametes and zygotes, that plumbing has become increasingly elaborate, and that part of the system that was once just a convenient throughway has become a destination and a long-term residence in its own right.
Development tells us part of the story. The reproductive and urinary tracts are all tangled together in early development, arising together from two pairs of ducts, the Müllerian and Wolffian ducts, which are modified in complex ways to form a series of kidneys (we keep only the last one, the metanephros), one set of pathways for the male testes, and yet another set for the female ovaries.
In non-therian mammals, all of these complicated pipes have one common destination, a single outlet to the external world: the cloaca. Cloaca is Latin for sewer, and it is appropriately named. The terminus of the large intestine is here, as well as the ends of the ureters from the kidneys and the ducts from the ovaries or testes. Everything gets dumped in to the cavity of the cloaca, making a nice stew of feces, urine, and sperm or eggs. Mmm-mmm. The cloaca is the grey cylinder at the bottom of figure A, below, in the first three organisms, amphibians, birds/reptiles, and monotremes (my apologies for the murkiness of the image; it's the best copy I have).
tetra_repro_evo.jpg
(Click for larger image)

Evolution of the tetrapod reproductive system. (A) Female urogenital system from major tetrapod lineages. Inf, infundibulum; Ov, ovary; Ovd, oviduct; Ut, uterus (or shell-producing region in non-therian animals); Vg, vagina; Kd, kidney; Ud, urinary duct; Rc, rectum; Ub, urinary bladder; Cl, cloaca. (B) Tetrapod egg. *, the shell coat of birds and some reptiles is highly calcified. MPS, marsupial-specific mucopolysaccharide layer. (C) Tetrapod phylogeny showing major transitions in mammalian reproduction. Divergence of amphibians and amniotes (A). Divergence of birds/reptiles and mammals (B). Divergence of monotremes and therians (C). Divergence of marsupials and placentals (D).
The fundamental organization of the reproductive part of the vertebrate urogenital tract is straightforward: it's a tube with a funnel at one end that captures eggs released by the ovary, and conducts them to an external orifice. Along the way, cells lining the tube secrete useful products like albumin and yolk, and deposit a shell, and may act to temporarily store the egg before its final release.
Marsupial and placental mammals have dispensed with most of those functions, and expanded on others. One part of the oviduct has acquired a richly vascularized epithelium and specializations for investing and nurturing a resident embryo, becoming a uterus. That's an amazing and innovative function in itself, but in addition, it has formed a new, separate channel, the vagina. The vagina is an entirely new structure, which has no homolog in amphibians or reptiles.
That is an interesting observation. It's a wholly original structure that arose sometime after the monotreme-marsupial split, an evolutionary novelty. How did that happen? How can we study a unique event that occurred over 150 million years ago?
marsupial_origins.gif
(click for larger image)

Evolutionary tree showing placement of the three groups of living mammals (colored boxes and icons at top) with respect to selected Mesozoic taxa. Branching times for the black tree are based on the earliest known fossil occurrences of taxa (black dots).The red tree is based on molecular divergence times for monotremes-therians and eutherians- metatherians.
Wagner and Lynch have a proposal to answer both questions. The general mechanism for generating novel structures is evo-devo orthodoxy:
  1. An epigenetic side effect of other evolutionary changes in the body leading to a novel physical structure in the organisms.
  2. The genetic consolidation and individuation of the novel structure.
(Note that this proposes phenotype before genotype, which is somewhat heretical for neodarwinism. It shouldn't trouble the evo-devo gang in the slightest, of course.)
How to study such a process from the past?
The basic assumption of a molecular evolutionary approach to the study of evolutionary novelties is that changes in developmental regulation have left traces in the molecular structure of the genome and a comparative study of genomic structures should be able to identify genetic changes coincidental with a phenotypic novelty. (emphasis mine)
That process of consolidation and individuation would have left detectable scars in the genome—the genes involved would have acquired changes necessary to fix the phenotype in the population. Again, as we'd expect from the evo-devo perspective, those changes would have been made to the regulatory genes that control tissue-specific gene expression. What genes should we examine? Let's look at the therian organs of interest, and here are some likely candidates: the HoxA genes that have region-specific domains in the female reproductive tract.
hox_repro_tract.jpg
Hox gene expression pattern and the evolution of the female reproductive tract. (a) HoxA-13 to HoxA-9 are located at the 5' end of the HoxA cluster and are expressed in the same regions in the adult as in the embryo: HoxA-13 (green), HoxA-11 (yellow), HoxA-10 (orange) and HoxA-9 (blue). (b) Tetrapod phylogeny showing representative female reproductive systems from each group (amphibian ovaries shown only on the left).
hoxa11_phylo.gif
Phylogenetic relationships among a small set of vertebrate species including representatives of the major mammalian clades: monotremes (platypus), marsupials (opposum) and placentals (Hyrax and human). Above some branches the estimated number of non-synonymous and synonymous substitutions of HoxA-11. The estimates are obtained from a maximum likelihood codon model as implemented in PAML. Note that in the stem lineages of therians (i.e., the lineage leading to the most recent common ancestor of opossum and the placentals), there are five to six non-synonymous substitutions but no synonymous substitution. This indicates a very strong selection coincidental with the evolution of the internal developmental mode of mammals.
The HoxA-9 through HoxA-13 genes are expressed in order along the length of the embryonic Müllerian duct, and also continue to be expressed in adulthood; so the cells of the vagina are all expressing HoxA-13, while the cells of the cervix all have HoxA-11 turned on (for some reason, I find that to be a wonderful piece of knowledge, and I just have to say…Hooray for HoxA-13! It has just become my favorite Hox gene.)
So the question is whether there is any evidence that these particular Hox genes have signs of any set of changes that are associated with particular transitions in vertebrate evolution—in particular, are there differences that can be traced to the transition between monotremes and the theria, and between the placentals and marsupials. The answer seems to be yes: the diagram to the right is a measure of the number of synonymous to nonsynonymous changes in HoxA-11, which is an indicator of the selective pressures that have shaped the gene.
Furthermore, they've identified where these changes have occurred, and they are not in the homeodomain (the part of the protein that binds to specific sequences in the DNA, but in the amino terminal end.
hoxa11_var.gif
Approximate positions of the amino acids positions of HoxA-11 which are under directional selection between the most recent common ancestor of all extant mammals and the most recent common ancestor of placentals. Note that all of these substitutions are N-terminal of the homeodomain and affect small clusters of amino acids.
The 3-D models below show where the relevant amino acids (in yellow) end up in the folded protein. The interesting thing here is that regulatory proteins don't just interact with each other, but also with other regulatory proteins that are simultaneously binding. It's a whole chain of interactions—regulatory proteins binding to the DNA, and also binding between each other in a complex called the enhancersome—that determines the level of expression of a particular gene.
hoxa11_struc.jpg
HoxA-11 protein structure. This three-dimensional protein model was calculated by comparative modeling as part of the MODBASE project. (A) Model shown as ribbons. (B) Model rendered with a molecular surface. The DNA-binding homeodomain is shown in red. The carboxy-terminal region of exon 2 is shown in blue. Residues identified as being under directional (positive) selection in the stem lineage of eutherians are shown in yellow. Residues replaced in the stem lineage of therians but not identified under selection are shown in green. Note that all of these amino acid sites affect amino acids that are predicted to be placed on the surface of the molecule as expected if selection is driven by novel protein-protein interactions.
There is a great deal left to be done. Hox genes are rather high up the chain of regulatory genes, so there are many more genes downstream that have to be puzzled out. We also are a long ways from figuring out how these patterns of gene expression define the morphogenetic processes that create this lovely novel structure, the vagina. The important thing, though, is that there are these questions waiting to be answered—the investigators have a research program.
We propose that a research program to explain evolutionary novelties has to focus on the question of whether novel characters arise through the evolution of novel regulatory links among developmental genes. We further propose that a detailed analysis of the evolution of developmental genes involved in the development of a derived, novel character can reveal molecular changes that could be causally involved in the origin of evolutionary novelties. The case study presented here suggests that the statistical methods of molecular evolution are strong enough to provide specific hypothesis for experimental test. The success of this research program will depend on the ability to connect the patterns of molecular evolution with the functional role of these molecular changes.
That's the cool thing about evolutionary biology: exciting questions, titillating ancestors, and the promise of tools to answer more.

Lynch VJ, Roth JJ, Takahashi K, Dunn CW, Nonaka DF, Stopper GF, Wagner GP (2004) Adaptive evolution of HoxA-11 and HoxA-13 at the origin of the uterus in mammals. Proc Biol Sci. 271(1554):2201-7. [pdf]
Wagner GP, Lynch VJ (2005) Molecular evolution of evolutionary novelties: the vagina and uterus of therian mammals. J Exp Zoolog B Mol Dev Evol. [Epub ahead of print]
Cifelli RL, Davis BM (2003) Marsupial Origins. Science 302:1899-1900.


segunda-feira, 27 de julho de 2009

Como evoluiu o pénis? Penis evolution

Quem está na blogosfera (e não só) procura ou é insistentemente convidado a aumentar o tráfego de visitantes do seu blogue ou página. Toda a gente sabe que o sexo é um tema que tem muita procura. Bom mas podemos falar dele de uma forma séria e interessante. Porque não uma abordagem sobre a evolução dos principais órgãos sexuais: o pénis e a vagina?
Embora em inglês, quem melhor para abordar a evolução do pénis por PZ Myers (biólogo e Professor Associado da Universidade de Minnesota, Morris).

Resumo do artigo Penis Evolution ( originalmente em inglês: mais abaixo)
Os pénis embrionários tiveram uma história complexa. Eles evoluíram independentemente várias vezes, e talvez o mais preocupante para o ego masculino, que tenham sido perdidos secundariamente, pelo menos, algumas vezes. E cada vez que eles têm evoluído, as evoluções convergem numa solução morfológica notavelmente semelhante.
So I was just browsing through some fun journals (Integrative and Comparative Biology, always good for some unusual stuff) and ran across a paper with a wonderful title: "The Functional Morphology of Penile Erection: Tissue Designs for Increasing and Maintaining Stiffness." If that kind of thing will sell commercial air time during the Super Bowl, it's got to be popular.
As is typical, though, while the promise of salaciousness drew me in, it was the science and the evolutionary story that kept me interested. Amniote penises have had a complex history. They have evolved independently multiple times, and perhaps most troubling to the male ego, they have been secondarily lost at least a few times. And every time they have evolved, they converge on a remarkably similar morphological solution.
That last observation is perhaps not very surprising. The penis has a very simple job to do: to maintain sufficient stiffness to enter an orifice in the mate, and to deliver sperm. That's it. Every amniote settles on a similar solution, forming a hydrostat, a tube containing a pressurized incompressible fluid surrounded by a membrane under tension. It's a kind of glorified water balloon.
Where different amniote lineages differ is in how they build their penis. Mammals have a medial penis containing two inflatable, vascular erectile bodies, and the tissue used for it embryonically is gathered from non-cloacal epithelia and connective tissue. Crocodile and turtle penises contain a single erectile body, and they form their penises from tissues on the ventral cloacal wall. Squamates (lizards and snakes) have paired penises built from lateral cloacal wall tissue. Birds, like crocodiles, assemble a penis (when they have one) from the ventral wall of the cloaca, but they use the lymphatic system as a pump, rather than the blood system.

In these cross-sections through the penises of a turtle, bird, mammal, and snake, you can see that while each is different in its organization, all contain the same kind of functional core: a vascular space (VS) surrounded by a tensile membrane (TM).

Diagrams illustrating transverse sections of amniote intromittent organs. A turtle penis is at the upper left, a bird penis is at the upper right, a mammalian penis is at the lower left, and a snake hemipene is at the lower right. All the structures are hydrostatic: each contains a central vascular space (VS) and surrounding tensile membrane (TM) characteristic of hydrostats.
Similar in function, but different in embryonic origin—this all suggests that these organs evolved independently. There are multiple hypotheses about the exact order and pattern of descent of the penis—the diagrams below illustrate two—but one of the striking things about this pattern is how lineages, such as the birds, can so blithely lose their intromittent organ. Most birds lack penises altogether, and they are found mainly in ratites and ducks, yet both of the cladograms below show that the ancestral bird most likely had one. Think about that… it hasn't been at all uncommon for female vertebrates to be untroubled by the absence of a penis in their mates, and apparently have preferred it that way.



Phylogeny of extant amniotes illustrating alternate hypotheses for the distribution of intromittent organs in amniotes. A. The penis is an amniote synapomorphy. B. The penis as a convergent trait. The position of the Testudines is disputed; alternate hypotheses increase the possible number of independent penile origins, as does the patchy distribution of the organ within Aves.
This paper presents the evolutionary history of the penis as background to its primary focus, which is on the bioengineering of a rigid hydrostat. All of the organisms converge on an exceedingly similar solution. The tensile membrane of the hydrostat consists of alternating layers of collagen fibers, each oriented at 90° to one another. This is the same principle used to give plywood its rigidity, by having fibers oriented to oppose bending along their least extensible axis at every angle. In addition, the fibers in the rest state are crimped, allowing them to stretch during extension, but then become straight and resistent to further extension when the organ is fully inflated.


Diagram of collagen fiber arrangement in the wall tissue of a flaccid mammalian penis. There are two layers forming an axial orthogonal array: an outer layer with fibers at 0° to the long axis of the penis and an inner layer with fibers at 90° to the long axis. Collagen fibers are highly crimped in the flaccid penis, but straighten upon erection.

The paper also describes some experimental measures of stiffness. The author extracts the penis of the nine-banded armadillo, and can then pump it up by inflating it with known volumes of fluid, whele measuring its resistance to bending (reported as values of E, or Young's modulus of elasticity.) I confess to having the odd thought that locker-room bragging ought to supplement reports of inches/centimeters of length with E values in 10-5Nm2. Imagine all the insecure jocks reporting to their local physiologist for a three-point bending test!



Change in the average flexural stiffness of mammalian penile erectile tissue (corpus cavernosum) during inflation, as measured by three-point bending tests in the nine-banded armadillo (Dasypus novemcinctus). Flexural stiffness increases as internal volume increases, and is highest when the corpus cavernosum reaches maximum volume. There is not a statistically significant difference in the flexural stiffness of the corpus cavernosum when the structure is bent laterally or dorsoventrally (n=4; F-ratio=2.70; 0.05
The author concludes from the degree of convergence seen in the species studied that there must be adaptive significance to the arrangement.
What, then, can we conclude if we observe convergence at more than one anatomical or functional level? Multiple levels of convergence could imply that there are more constraints on the system—that there are fewer possible anatomical designs that successfully meet the selective regime. Therefore, if there is only one way to solve the problem imposed by the selective regime, we will see convergence at more levels than if many equally successful anatomies can evolve.
If this hypothesis is true, the evidence from mammals and turtles suggests that the amniotes that have evolved inflatable penises have been subjected to an extremely restrictive selective regime. Penile convergence in mammals and turtles does not stop at gross functional similarity; they have converged on a single anatomical design down to the level of specific collagen fiber arrangements. The differences in penile collagen fiber layering that exist between mammals and turtles do not, as of yet, seem to have any functional effect on penile stiffness. It may be that the way the axial orthogonal array is put together is less critical to the problem of increasing penile flexural stiffness than the presence of the array itself.
I agree in part, but it also seems to me that contingency is equally significant. The reason that all of these animals have converged on the same solution is that they've begun with similar raw materials: a high-pressure circulatory system and a tissue bed rich in the protein collagen.
There was no mention of the adaptive significance of this organ to weblogging or to administering Harvard, to my disappointment.

Kelly DA (2002) The Functional Morphology of Penile Erection: Tissue Designs for Increasing and Maintaining Stiffness. Integ. and Comp. Biol. 42:216–221.


sábado, 25 de julho de 2009

Depoimentos no projecto 6 Mil Milhões como Tu- Liberdade


São originalmente cinco mil entrevistas filmadas em 75 países por seis realizadores que foram ao encontro dos Outros como Tu!
[Saber mais em Futura-Sciences]

Consultar também esta postagem no BioTerra.

sexta-feira, 24 de julho de 2009

Dossier Bicicleta

ATENÇÃO © Copyleft - É permitida a partilha do dossiê exclusivamente para fins não comerciais e desde que o autor e o BioTerra sejam citados.


Não esqueças de visitar regularmente este espaço para manteres-te actualizado.


  • Uma brilhante compilação de dados feitas por este brilhante blogue da Dinamarca, com fotos muito criativas (como esta) relembrando os perigos de condução e dos riscos ambientais do uso excessivo do automóvel - Driving Kills - Health Warnings

  • Todas as postagens do Bioterra com a etiqueta Bicicleta

Eis uma selecção (espectacular) de blogues e sítios dedicados à cultura da bicicleta [e não só], também existente no referido blogue
NOVA ATENÇÃO © COPYRIGHT-  Ao partilhar, agradeço atempadamente a indicação do autor e do meu blogue Bioterra. Estes dossiês resultam de um apurado trabalho de pesquisa, selecção de qualidade e organização.

quinta-feira, 23 de julho de 2009

6 Mil Milhões como Nós (6 billion others) - mais um projecto de Yann Arthus-Bertrand


6 Billion others é um projecto excepcional de grande qualidade, é um retrato contemporâneo que reflecte a nossa humanidade através de perguntas diversas, banais e universais, com diferentes pessoas de diferentes países.
6.000 entrevistas realizadas, 65 paíse visitados, 4.500 horas de entrevistas filmadas, foi o magnífico trabalho de Yann Arthus-Bertrand



segunda-feira, 20 de julho de 2009

Richard Dawkins e o Gene Egoísta



Curiosamente, os apelos em tempo de paz para os indivíduos fazerem qualquer pequeno sacrifício na taxa de aumento do seu nível de vida para ser menos eficiente que os apelos, durante o tempo de guerra, para que dêem a sua vida.[página 31]



domingo, 19 de julho de 2009

Ecovoluntariado e turismo alternativo

Escolha um lugar Organização Escolha um lugar Preguntas mais frequentas

Você poderia dizer que o Ecovolunteer Program funciona como uma agência de viagens. Porém, as viagens que nós organizamos não são viagens comuns. Elas o levam a lugares não acessíveis a turistas. Lugares onde você tem a possibilidade de proteger a natureza e seus habitantes, ajudando a organizações locais através de projetos de conservação. Isto faz uma viagem do Ecovolunteer Program ser gratificante e também uma experiência inesquecível.
Escolha um lugar
Escolha uma espécie
Calendário
Novidades



Quadro completamente interactivo. Se tiver dificuldade de navegação, clique aqui.Num momento em que o turismo de voluntariado começa a ser desejado como forma de preencher mais produtivamente o tempo de férias, eis uma óptima sugestão.
Nota: Antes de escolher pergunte a si mesmo: quero mesmo viajar de avião? Pense primeiro na redução da sua pegada de carbono. Obrigado.



sábado, 18 de julho de 2009

10 maneiras de ser solidário através dos média sociais disponíveis


Tradução em espanhol disponível em Stralunato

This content was originally written by Mashable's Josh Catone.
This guest post is a collaboration between Mashable's Summer of Social Good charitable fundraiser and Max Gladwell's "10 Ways" series. The post is being simultaneously published across more than 100 blogs.
summerofsocialgoodnew
Social media is about connecting people and providing the tools necessary to have a conversation. That global conversation is an extremely powerful platform for spreading information and awareness about social causes and issues. That's one of the reasons charities can benefit so greatly from being active on social media channels. But you can also do a lot to help your favorite charity or causes you are passionate about through social media.
Below is a list of 10 ways you can use social media to show your support for issues that are important to you. If you can think of any other ways to help charities via social web tools, please add them in the comments. If you'd like to retweet this post or take the conversation to Twitter or FriendFeed, please use the hashtag #10Ways.
1. Write a Blog Post
Blogging is one of the easiest ways you can help a charity or cause you feel passionate about. Almost everyone has an outlet for blogging these days -- whether that means a site running WordPress, an account at LiveJournal, or a blog on MySpace or Facebook. By writing about issues you're passionate about, you're helping to spread awareness among your social circle. Because your friends or readers already trust you, what you say is influential.
Recently, a group of green bloggers banded together to raise individual $1 donations from their readers. The beneficiaries included Sustainable Harvest, Kiva, Healthy Child, Healthy World, Environmental Working Group, and Water for People. The blog-driven campaign included voting to determine how the funds would be distributed between the charities. You can read about the results here. You should also consider taking part in Blog Action Day, a once a year event in which thousands of blogs pledge to write at least one post about a specific social cause (last year it was fighting poverty). Blog Action Day will be on October 15 this year.

2. Share Stories with Friends
twitter-links Another way to spread awareness among your social graph is to share links to blog posts and news articles via sites like Twitter, Facebook, Delicious, Digg, and even through email. Your network of friends is likely interested in what you have to say, so you have influence wherever you've gathered a social network. You'll be doing charities you support a great service when you share links to their campaigns, or to articles about causes you care about.

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3. Follow Charities on Social Networks

In addition to sharing links to articles about issues you come across, you should also follow charities you support on the social networks where they are active. By increasing the size of their social graph, you're increasing the size of their reach.
When your charities tweet or post information about a campaign or a cause, statistics or a link to a good article, consider retweeting that post on Twitter, liking it on Facebook, or blogging about it. Following charities on social media sites is a great way to keep in the loop and get updates, and it's a great way to help the charity increase its reach by spreading information to your friends and followers. You can follow the Summer of Social Good Charities:
Oxfam America (Twitter, Facebook, MySpace, Flickr, YouTube) The Humane Society (Twitter, Facebook, YouTube, MySpace, Flickr) LIVESTRONG (Twitter, Facebook, MySpace, YouTube, Flickr) WWF (Twitter, Facebook, YouTube, Flickr)

4. Support Causes on Awareness Hubs

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Another way you can show your support for the charities you care about is to rally around them on awareness hubs like Change.org, Care2, or the Facebook Causes application. These are social networks or applications specifically built with non-profits in mind. They offer special tools and opportunities for charities to spread awareness of issues, take action, and raise money.
It's important to follow and support organizations on these sites because they're another point of access for you to gather information about a charity or cause, and because by supporting your charity you'll be increasing their overall reach. The more people they have following them and receiving their updates, the greater the chance that information they put out will spread virally.
5. Find Volunteer Opportunities
Using social media online can help connect you with volunteer opportunities offline, and according to web analytics firm Compete, traffic to volunteering sites is actually up sharply in 2009. Two of the biggest sites for locating volunteer opportunities are VolunteerMatch, which has almost 60,000 opportunities listed, and Idealist.org, which also lists paying jobs in the non-profit sector, in addition to maintaining databases of both volunteer jobs and willing volunteers.
For those who are interested in helping out when volunteers are urgently needed in crisis situations, check out HelpInDisaster.org, a site which helps register and educate those who want to help during disasters so that local resources are not tied up directing the calls of eager volunteers. Teenagers, meanwhile, should check out DoSomething.org, a site targeted at young adults seeking volunteer opportunities in their communities.

6. Embed a Widget on Your Site

Many charities offer embeddable widgets or badges that you can use on your social networking profiles or blogs to show your support. These badges generally serve one of two purposes (or both). They raise awareness of an issue and offer up a link or links to additional information. And very often they are used to raise money. Mashable's Summer of Social Good campaign, for example, has a widget that does both. The embeddable widget, which was custom built using Sprout (the creators of ChipIn), can both collect funds and offer information about the four charities the campaign supports.

7. Organize a Tweetup

You can use online social media tools to organize offline events, which are a great way to gather together like-minded people to raise awareness, raise money, or just discuss an issue that's important to you. Getting people together offline to learn about an important issue can really kick start the conversation and make supporting the cause seem more real. Be sure to check out Mashable's guide to organizing a tweetup to make sure yours goes off without a hitch, or check to see if there are any tweetups in your area to attend that are already organized.

8. Express Yourself Using Video

As mentioned, blog posts are great, but a picture really says a thousand words. The web has become a lot more visual in recent years and there are now a large number of social tools to help you express yourself using video. When you record a video plea or call to action about your issue or charity, you can make your message sound more authentic and real.
You can use sites like 12seconds.tv, Vimeo, and YouTube to easily record and spread your video message. Last week, the Summer of Social Good campaign encouraged people to use video to show support for charity. The #12forGood campaign challenged people to submit a 12 second video of themselves doing something for the Summer of Social Good.
That could be anything, from singing a song to reciting a poem to just dancing around like a maniac -- the idea was to use the power of video to spread awareness about the campaign and the charities it supports. If you're more into watching videos than recording them, Givzy.com enables you to raise funds for charities like Unicef and St. Jude's Children's Hospital by sharing viral videos by e-mail.

9. Sign or Start a Petition

twitition There aren't many more powerful ways to support a cause than to sign your name to a petition. Petitions spread awareness and, when successfully carried out, can demonstrate massive support for an issue. By making petitions viral, the social web has arguably made them even more powerful tools for social change.
There are a large number of petition creation and hosting web sites out there. One of the biggest is The Petition Site, which is operated by the social awareness network Care2, or PetitionOnline.com, which has collected more than 79 million signatures over the years. Petitions are extremely powerful, because they can strike a chord, spread virally, and serve as a visual demonstration of the support that an issue has gathered.
Social media fans will want to check out a fairly new option for creating and spreading petitions: Twitition, an application that allows people to create, spread, and sign petitions via Twitter.

10. Organize an Online Event

Social media is a great way to organize offline, but you can also use online tools to organize effective online events. That can mean free form fund raising drives, like the Twitter-and-blog-powered campaign to raise money for a crisis center in Illinois last month that took in over $130,000 in just two weeks. Or it could mean an organized "tweet-a-thon" like the ones run by the 12for12k group, which aims to raise $12,000 each month for a different charity.
In March, 12for12k ran a 12-hour tweet-a-thon, in which any donation of at least $12 over a 12 hour period gained the person donating an entry into a drawing for prizes like an iPod Touch or a Nintendo Wii Fit. Last month, 12for12k took a different approach to an online event by holding a more ambitious 24-hour live video-a-thon, which included video interviews, music and sketch comedy performances, call-ins, and drawings for a large number of prizes given out to anyone who donated $12 or more.