The recent discovery of super-Earths (masses ≤ 10 M⊕) has initiated a discussion about conditions for habitable worlds. Among these is the mode of convection, which influences a planet’s thermal evolution and surface conditions. On Earth, plate tectonics has been proposed as a necessary condition for life. Here we show, that super-Earths will also have plate tectonics. We demonstrate that as pl...

The recent discovery of super-Earths (masses ≤ ) has initiated a discussion about conditions for habitable 10 M worlds. Among these is the mode of convection, which influences a planet’s thermal evolution and surface conditions. On Earth, plate tectonics has been proposed as a necessary condition for life. Here we show that super-Earths will also have plate tectonics. We demonstrate that as pla...

This is a short history of the Smithsonian Microbeam Standards; their sources, selection, preparation, and analyses. Fifty-eight minerals, natural glasses, and synthetic samples have been characterized in the past 25 years. During that time, over 750 requests were received for approximately 11 000 individual samples. These reference samples are referred to as the Smithsonian Microbeam Standards.

BACKGROUND Previous research relating dietary fat, a modifiable risk factor, to pancreatic cancer has been inconclusive. METHODS We prospectively analyzed the association between intakes of fat, fat subtypes, and fat food sources and exocrine pancreatic cancer in the National Institutes of Health-AARP Diet and Health Study, a US cohort of 308 736 men and 216 737 women who completed a 124-item...

Context Tuberculosis (TB) has been described as the biggest killer in human history. Mycobacterium tuberculosis emerged over 70 000 years ago, and it has shared evolutionary paths with modern humans since their early migration out of Africa [1]. With the expansion of human populations and the emergence and change of livelihoods and lifestyles, M. tuberculosis evolved and diversified, and contin...

Abstract The radius valley, a bifurcation in the size distribution of small, close-in exoplanets, is hypothesized to be signature planetary atmospheric loss. Such an evolutionary phenomenon should depend on age star–planet system. In this work, we study temporal evolution valley using two independent determinations host star ages among California–Kepler Survey (CKS) sample. We find evidence for...

Orthodontics has been developing for 282 years. We can distinguish an initial period when practitioners limited themselves to ‘‘straightening’’ teeth that were out of position. Then, under the influence of Edward Hartley Angle, they devoted their efforts to correcting ‘‘malocclusions.’’ Now, during its third period, orthodontics has divided itself into two branches. The American school believes...

It is shown that rare earths can be distributed between two immiscible ionic liquids, allowing the transfer of the rare earths from one ionic liquid phase to another. The ionic liquid 1-ethyl-3-methylimidazolium chloride was used as the initial feed phase and the ionic liquid trihexyl(tetradecyl)phosphonium bis(2,4,4trimethylpentyl)phosphinate (Cyphos IL 104) as the extracting phase. The rare e...

Cicero’s brain and vibrating nerves Few pairs of books about the history of the brain could be more discordant than this one. Daniel Lord Smail, a Harvard historian, makes a strong plea for integrating the general history of mankind with the evolutionary history of the brain. No mean task, certainly not for someone whose first book, published in 1999, examined changes in spatial designation in ...