microbiologybytes: Fifty Shades of Immune Defence This great paper appeared in PLOS Pathogens recently. I’ll let you read it for yourself, but to summarize: Innate and Adaptive Immunity Are No Longer Black and White; There Are Increasing Shades of Grey The Immunoglobulin Superfamily (IgSF) Is Neither the Only Nor the Oldest Antigen Receptor System Invertebrate Immune Cells Have Complex Receptor Systems, Possibly Affording Adaptive Immunity Forms of Immunological Memory May Well Exist in Nonvertebrates, Even in Prokaryotes Comparative Immunologists Will Not Be the Sole Beneficiaries of These Discoveries Fifty Shades of Immune Defense. (2013) PLoS Pathog 9(2): e1003110. doi:10.1371/journal.ppat.1003110
Pop-upView Separately

microbiologybytes:

Fifty Shades of Immune Defence

This great paper appeared in PLOS Pathogens recently. I’ll let you read it for yourself, but to summarize:

  1. Innate and Adaptive Immunity Are No Longer Black and White; There Are Increasing Shades of Grey
  2. The Immunoglobulin Superfamily (IgSF) Is Neither the Only Nor the Oldest Antigen Receptor System
  3. Invertebrate Immune Cells Have Complex Receptor Systems, Possibly Affording Adaptive Immunity
  4. Forms of Immunological Memory May Well Exist in Nonvertebrates, Even in Prokaryotes
  5. Comparative Immunologists Will Not Be the Sole Beneficiaries of These Discoveries

Fifty Shades of Immune Defense. (2013) PLoS Pathog 9(2): e1003110. doi:10.1371/journal.ppat.1003110

(via scientificillustration)

Source: microbiologybytes.com

abluegirl: Dinosaur-killing space rock ‘was a comet’ Scientists believe that the object that hit the earth 65 million years ago, triggering the extinction of the dinosaurs, was a comet, not an asteroid.  Comets are typically smaller, but faster moving than asteroids.  This one resulted in the 180-km wide Chicxulub crater in Mexico, and would have triggered the global environmental change that caused the extinction event.  Here’s more from BBC News: The space rock gave rise to a global layer of sediments enriched in the chemical element iridium, in concentrations much higher than naturally occurs; it must have come from outer space. However, in the first part of their work, the team suggests that frequently quoted iridium values are incorrect. Using a comparison with another extraterrestrial element deposited in the impact - osmium - they were able to deduce that the collision deposited less debris than has previously been supposed. The recalculated iridium value suggests a smaller body hit the Earth. So for the second part of their work, the researchers took the new figure and attempted to reconcile it with the known physical properties of the Chicxulub impact. For this smaller space rock to have produced a 180km-wide crater, it must have been travelling relatively quickly. The team found that a long-period comet fitted the bill much better than other possible candidates. “You’d need an asteroid of about 5km diameter to contribute that much iridium and osmium. But an asteroid that size would not make a 200km-diameter crater,” said Dr Moore. “So we said: how do we get something that has enough energy to generate that size of crater, but has much less rocky material? That brings us to comets.” Full Article
Pop-upView Separately

abluegirl:

Dinosaur-killing space rock ‘was a comet’

Scientists believe that the object that hit the earth 65 million years ago, triggering the extinction of the dinosaurs, was a comet, not an asteroid.  Comets are typically smaller, but faster moving than asteroids.  This one resulted in the 180-km wide Chicxulub crater in Mexico, and would have triggered the global environmental change that caused the extinction event.  Here’s more from BBC News:

The space rock gave rise to a global layer of sediments enriched in the chemical element iridium, in concentrations much higher than naturally occurs; it must have come from outer space.

However, in the first part of their work, the team suggests that frequently quoted iridium values are incorrect. Using a comparison with another extraterrestrial element deposited in the impact - osmium - they were able to deduce that the collision deposited less debris than has previously been supposed.

The recalculated iridium value suggests a smaller body hit the Earth. So for the second part of their work, the researchers took the new figure and attempted to reconcile it with the known physical properties of the Chicxulub impact.

For this smaller space rock to have produced a 180km-wide crater, it must have been travelling relatively quickly. The team found that a long-period comet fitted the bill much better than other possible candidates.

“You’d need an asteroid of about 5km diameter to contribute that much iridium and osmium. But an asteroid that size would not make a 200km-diameter crater,” said Dr Moore.

“So we said: how do we get something that has enough energy to generate that size of crater, but has much less rocky material? That brings us to comets.”

Full Article

(via scinerds)

Source: BBC

freshphotons: “In its natural environment, Drosophila melanogaster feeds on yeasts that grow on sugar-rich substrates such as fermenting fruit. Fruits, however, also harbor toxic microbes, and flies need to distinguish those microbes that are safe and nutritious from the harmful ones. In this issue, Stensmyr et al. (pp. 1345–1357) demonstrate that flies detect toxic molds by sensing a volatile compound called geosmin, which exclusively triggers a dedicated signaling pathway in the flies’ olfactory system. This circuit, upon activation, causes innate aversion and also prevents egg laying and feeding. Cover concept by Rakel and Marcus Stensmyr. Clay modeling and photo by Marcus Stensmyr.”
Pop-upView Separately

freshphotons:

“In its natural environment, Drosophila melanogaster feeds on yeasts that grow on sugar-rich substrates such as fermenting fruit. Fruits, however, also harbor toxic microbes, and flies need to distinguish those microbes that are safe and nutritious from the harmful ones. In this issue, Stensmyr et al. (pp. 1345–1357) demonstrate that flies detect toxic molds by sensing a volatile compound called geosmin, which exclusively triggers a dedicated signaling pathway in the flies’ olfactory system. This circuit, upon activation, causes innate aversion and also prevents egg laying and feeding. Cover concept by Rakel and Marcus Stensmyr. Clay modeling and photo by Marcus Stensmyr.”

(via scientificillustration)

Source: cell.com

staceythinx:

Science is lovely in silk (at least it is in the hands of Karen Kamenetzky).

Kamenetzky on her work:

I dye, paint and stitch cottons and silks to create boldly colored wallhangings inspired by microscopic/cellular imagery - a kind of visual invented biology with textiles. I find this imagery metaphorically rich since all change fundamentally happens on this infinitesimal level.

(via freshphotons)

Source: karenkamenetzky.com