Einstein’s version of dark energy is known as the cosmological constant. It implies a fixed amount of dark energy in each cubic meter of space; as the universe expands, more dark energy appears. So ...
Having generated the two parental lines, we performed large-scale genetic crosses by pollinating male sterile lines with pollen obtained from the transplastomic lines. In this way, >2.5 million seeds ...
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Journal Club posts are short news stories featuring a recent important, timely journal article selected by one of our Journal Club panelists, who are post-doctoral associates and graduate students in ...
This finding documents smoke-dried mummification of the dead, mostly in tightly bound crouched postures, from archaeological contexts between 12,000 and 4,000 y old across a vast region encompassing ...
Phonon softening and crystallographic orientation of strained graphene studied by Raman spectroscopy
We present a systematic study of the Raman spectra of optical phonons in graphene monolayers under tunable uniaxial tensile stress. Both the G and 2D bands exhibit significant red shifts. The G band ...
Wildfires are a major source of fine particulate matter (diameter <2.5 µm; PM 2.5), which is a health hazard. Since the mid-1980s, the total US area burned by wildfires has been increasing, with fires ...
Formation of knots in mathematical self-avoiding random walks has been extensively studied (10 – 16). In the 1960s, Frisch and Wasserman (10) and Delbruck (11) conjectured that the probability of ...
Open in Viewer (A) Schematic of a photocell consisting of quantum dots sandwiched between p and n doped semiconductors. Open circuit voltage and solar photon energy ℏνh are related by the Carnot ...
Lower socioeconomic status (SES) is a determinant of many of the health problems that emerge at older ages. The extent to which lower SES is associated with faster decline in age-related functions and ...
Open in Viewer Evolution of atmospheric CO 2 (a), methane (b), and nitrous oxide (c), and sampling intervals (d) over the past 20,000 years. The gray bar denotes the range of the preindustrial, ...
We show that for thousands of years, humans have concentrated in a surprisingly narrow subset of Earth’s available climates, characterized by mean annual temperatures around ∼13 °C. This distribution ...
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