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Posts Tagged ‘science

[LINK] “Atlantic Ocean slows global warming, but scientists believe hiatus will end around 2030″

The CBC/Reuters account is very worrisome.

The Atlantic Ocean has masked global warming this century by soaking up vast amounts of heat from the atmosphere in a shift likely to reverse from around 2030 and spur fast temperature rises, scientists said.

The theory is the latest explanation for a slowdown in the pace of warming at the Earth’s surface since about 1998 that has puzzled experts because it conflicts with rising greenhouse gas emissions, especially from emerging economies led by China.

“We’re pointing to the Atlantic as the driver of the hiatus,” Ka-Kit Tung, of the University of Washington in Seattle and a co-author of Thursday’s study in the journal Science, told Reuters.

The study said an Atlantic current carrying water north from the tropics sped up this century and sucked more warm surface waters down to 1,500 metres (5,000 feet), part of a natural shift for the ocean that typically lasts about three decades.

It said a return to a warmer period, releasing more heat stored in the ocean, was likely to start around 2030. When it does, “another episode of accelerated global warming should ensue”, the authors wrote.

Written by Randy McDonald

August 22, 2014 at 8:17 pm

[LINK] “Readers absorb less on Kindles than on paper, study finds”

Alison Flood’s article in The Guardian about the apparent issues associated with reading ereaders resonated with me, as it did with people around the world. I generally prefer reading from books to reading online, having noticed the same comprehension and retention issues in my own reading.

I wonder what the consequences will be in the future, when so much more reading material is only going to be online. Will ereaders technology advance enough?

The study, presented in Italy at a conference last month and set to be published as a paper, gave 50 readers the same short story by Elizabeth George to read. Half read the 28-page story on a Kindle, and half in a paperback, with readers then tested on aspects of the story including objects, characters and settings.

Anne Mangen of Norway’s Stavanger University, a lead researcher on the study, thought academics might “find differences in the immersion facilitated by the device, in emotional responses” to the story. Her predictions were based on an earlier study comparing reading an upsetting short story on paper and on iPad. “In this study, we found that paper readers did report higher on measures having to do with empathy and transportation and immersion, and narrative coherence, than iPad readers,” said Mangen.

But instead, the performance was largely similar, except when it came to the timing of events in the story. “The Kindle readers performed significantly worse on the plot reconstruction measure, ie, when they were asked to place 14 events in the correct order.”

The researchers suggest that “the haptic and tactile feedback of a Kindle does not provide the same support for mental reconstruction of a story as a print pocket book does”.

“When you read on paper you can sense with your fingers a pile of pages on the left growing, and shrinking on the right,” said Mangen. “You have the tactile sense of progress, in addition to the visual … [The differences for Kindle readers] might have something to do with the fact that the fixity of a text on paper, and this very gradual unfolding of paper as you progress through a story, is some kind of sensory offload, supporting the visual sense of progress when you’re reading. Perhaps this somehow aids the reader, providing more fixity and solidity to the reader’s sense of unfolding and progress of the text, and hence the story.”

Written by Randy McDonald

August 22, 2014 at 8:14 pm

[LINK] “Ebola outbreak: Africans understandably wary about promised cures”

CBC’s Daniel Schwartz examines how, in the context of the expanding Ebola epidemic, African skepticism about foreign medical systems is often grounded in recent bad experience with said.

For example, in Nigeria in 1996, when a meningitis epidemic was underway, the American pharmaceutical company Pfizer arrived in the hot zone in Kano. Its representatives immediately set up their clinic next to the makeshift tents of a hospital then staffed mostly by Doctors Without Borders.

Meningitis, an inflammation in a membrane surrounding the brain or spinal cord, affects mostly children, and without treatment, about half of those infected will die.

Pfizer had a new treatment that it wanted to test, so its doctors gave Trovan (floxacin) to about half the 200 children they treated, while the other half received an approved drug for meningitis.

About five per cent of the patients taking the experimental Trovan died, while some others were left blind, deaf and/or paralyzed.

In the aftermath, the U.S. Food and Drug Administration refused to approve Trovan, hundreds of Nigerian parents sued Pfizer and the company eventually settled in 2009. (Its position was that it was the disease that had caused the deaths and other conditions.)

Pfizer claimed to have permission from the local hospital to conduct its experiment, but the approval letter was said to be a forgery. Pfizer claimed it had informed consent from the patients’ families but could not provide written proof.

Harriet Washington, who wrote about the Trovan case in her 2011 book Deadly Monopolies, told CBC News that in the absence of that consent, people in Kano “had no way of distinguishing the doctors who are giving approved drugs meant to work, from doctors right next to them who are giving them something experimental.”

Written by Randy McDonald

August 20, 2014 at 7:53 pm

[LINK] “Our ancestor’s ‘leaky’ membrane answers big questions in biology”

Will Baird of The Dragon’s Tales linked to fascinating news that genetic analysis allows scientists to make informed speculation about the last universal common ancestor of life forms now extant on Earth. This is not the same as the first life form on Earth, it should be noted, but this is still remarkable progress.

Bacteria and archaea share many common features such as genes, proteins and mechanisms of reading DNA, initially leading scientists to believe they were just different types of bacteria. Their classification changed in the 1970’s after extreme differences were found in the way they replicate DNA and in the structure of their cell membrane. As they both stemmed from LUCA, scientists set out to find answers in the structure and function of LUCA’s membrane.

Dr Nick Lane (UCL Biosciences) who led the study said, “I find this work just beautiful – it constrains a sequence of steps going from the strange cell that seems to have been the ancestor of all life today, right through to the deep division between modern cells. From a single basic idea, the model can explain the fundamental differences between bacteria and archaea. Is it right? I’d like to think so, but more importantly, it makes some clear predictions that we plan to test in the future.”

Data from the study strongly suggest that LUCA lived in the area where ancient seawater, dense with positively charged particles called protons, mixed with warm alkaline vent fluid, which contained few protons. The difference in the concentration of protons across these two environments enabled protons to flow into the cell, driving the production of a molecule called adenosine triphosphate (ATP) which powered the growth of cells, just as it does today. However, unlike modern cells the scientists believe this could only happen if the membrane was ‘leaky’, enabling protons to leave the cell spontaneously so more protons could enter to power growth.

Dr Lane said: “In these deep sea vents, there is a continuous flow of alkaline fluids, which mix with the ocean waters. When they mix, the fluids neutralise each other, and that stops any build-up of charge which would otherwise prevent protons flowing into the cell. If the first cells had leaky membranes, then protons could enter and then be neutralised, or leave again, almost as if there was no barrier at all. What we’ve shown is that the rate at which protons enter and leave is high enough to power the growth of cells via proteins embedded in the membrane. So LUCA could have been powered by natural proton gradients in vents, but only if it had a really leaky membrane, completely unlike today’s cells.”

To escape from these seabed vents, LUCA had to adapt its membrane to pump protons out of the cell, in order for them to flow back in again to help drive ATP production. The study suggests that the bacteria and archaea developed completely different cell membrane structures and proton pumps, whilst keeping the same machinery for powering growth. It also explains why they differ in fundamental traits that depend on the membrane such as DNA replication.

Written by Randy McDonald

August 20, 2014 at 7:44 pm

Posted in Science

Tagged with , , , ,

[BLOG] Some Tuesday links

  • Bad Astronomy notes that some Ukrainian astronomers have insulted Putin by naming a star after him.
  • blogTO notes on the park front that the bandmembers of Rush will be honoured with a park in their own name in their own neighbourhood, and turns to the discussion about the
  • Broadside Blog’s Caitlin Kelly asks readers if they can describe their job in five words.
  • Joe. My. God. links to a new Australian study suggesting the children of same-sex couples might turn out better than the children of traditional family structures.
  • Language Hat links to an interesting speculation of Victor Mair’s, to the effect that all languages include at least a thousand basic concepts, suggesting this might reflect something about the human mind.
  • Language Log notes garbled language about the greenhouse effect on Earth and Mars.
  • Marginal Revolution suggests that, based on a study, the Chinese language has the lowest percentage of borrowed words of any major language.
  • Personal Reflection’s Jim Belshaw notes, as a white Australian, problems with being involved in the struggles of Aborigines.
  • Savage Minds notes the use of archeology in Israel to justify the displacement of Palestinians.
  • Towleroad examines how a picture of a gay male couple with their newborn child has gone viral.
  • The Volokh Conspiracy’s Will Baude shared the voices of some Americans critical of the Declaration of Independence. (Frederick Douglass’ issues were well-founded.)
  • Window on Eurasia notes the exile of another Crimean Tatar from his Russian-annexed homeland and observes a call for less education in languages other than Russian that might hit worldly Russians as badly as it would ethnic minorities.

[BLOG] Some Thursday links

  • blogTO shares pictures of the lineups for free food on Canada Day at Mandarin’s buffet restaurants.
  • The Dragon’s Gaze links to a paper identifying three thousand nearby red dwarf stars as potential sites of Earth-like exoplanets.
  • The Dragon’s Tales links to a sober assessment of the Chinese space program.
  • The Frailest Thing considers the import of Facebook’s experiment on its user base by noting the ability of complex systems to undergo unexpected catastrophes.
  • Joe. My. God. notes that Google’s social network Orkut, big in Brazil and India but absent elsewhere, will be shutting down at the end of this September.
  • Lawyers, Guns and Money notes that anti-gay activists are pleased with the Hobby Lobby ruling.
  • The Planetary Society Blog’s Adam Block shares pictures of colliding and interacting galaxies.
  • Seriously Science notes that not only do spiders have different personality types, but that these types contribute to the maintenance of their physical cultures.
  • The Signal notes ongoing research into data recovery methods and issues with compact discs.
  • The Volokh Conspiracy notes cases where putting the victim on trial does matter. (Records of past violence are noteworthy.)
  • Towleroad notes an economist observing that homophobia has an economic impact and points to an upcoming Irish referendum on same-sex marriage in 2015 that’s quite likely to pass.
  • Window on Eurasia quotes a Ukrainian about Russia’s issues with a separate Ukraine and notes a statement by Kaliningrad’s government claiming some Ukrainian refugees in Russia might be anti-Russian activists in disguise.

[NEWS] Some Wednesday links

  • Al Jazeera shares Sarah Kendzior’s argument that the disappearance of shopping malls will not mean the automatic return of downtowns in many cities, and notes the migration of many young Americans–including Vietnamese-Americans–to a booming Vietnam.
  • Business Week observes that in higher education, China wants more people with vocational degrees and fewer academics, while comments that the use of Minnan dialect by China’s spokesperson to Taiwan isn’t doing much to encourage reunification.
  • The CBC shares the request of American retailer target to its customers to please leave their guns home, and notes a finding in Québec that penalized Wal-Mart for closing down a store there after its workforce became unionized.
  • National Geographic notes evidence from an Archaeopreryx fossil that feathers evolved before flight, and comments on the cultural and other issues that make fighting the Ebola epidemic in West Africa so difficult.
  • Universe Today notes there are no lunar seas on the far side of the Moon because of the heat of the Earth in the Moon’s early days reached only the near side, and comments on the evidence of asteroid impacts on the surface of Vesta.
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