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Researchers Find Simple, Cheap Way to Increase Solar Cell Efficiency

By Guest PostJanuary 3, 2014Sciencechinese academy, donor:acceptor morphology, electron acceptor, electron donor, electronic structure, energy particles, energy source, fabrication costs, harald ade, highest, homo, jianhui hou, light, lijun huo, lowest, lumo, maojie zhang, molecular structure, north Carolina, occupied molecular orbit, pbt op, polymer, researcher, sciences, solar cells, state university, unoccupied molecular orbit, xray analysis

Researchers from North Carolina State University and the Chinese Academy of Sciences have found an easy way to modify the molecular structure of a polymer commonly used in solar cells. Their modification can increase solar cell efficiency by more than 30 percent.

Polymer-based solar cells have two domains, consisting of an electron acceptor and an electron donor material. Excitons are the energy particles created by solar cells when light is absorbed. In order to be harnessed effectively as an energy source, excitons must be able to travel quickly to the interface of the donor and acceptor domains and retain as much of the light’s energy as possible. (more…)

International Research Team Close Human Evolution Gap with Discovery of 1.4 Million-Year-Old Fossil Human Hand Bone

By Guest PostDecember 26, 2013Scienceanatomical features, apes, carol ward, earliest acheulian tools, east africa, evolutionary history, fossil, fredrick manthi, genus, hand anatomy, homo, human evolution gap, human hand bone, human like hand, kaitio site, Kenya, paleo project, styloid process, tool, university of missouri, west turkana

University of Missouri researcher part of team that found the bone in Kenya

COLUMBIA, Mo. – Humans have a distinctive hand anatomy that allows them to make and use tools. Apes and other nonhuman primates do not have these distinctive anatomical features in their hands, and the point in time at which these features first appeared in human evolution is unknown. Now, a University of Missouri researcher and her international team of colleagues have found a new hand bone from a human ancestor who roamed the earth in East Africa approximately 1.42 million years ago. They suspect the bone belonged to the early human species, Homo erectus. The discovery of this bone is the earliest evidence of a modern human-like hand, indicating that this anatomical feature existed more than half a million years earlier than previously known. (more…)

Ancient Humans Were Mixing it Up

By Guest PostSeptember 7, 2011Scienceafrica, archaic hominin forms, august woerner, central africa, chromosome, contemporary african populations, DNA, eurasia, fernando mendez, fossil, fossil specimens, genome, homo, homo sapiens, hybridization, jeffrey wall, joseph watkins, michael hammer, modern humans, molecular biology, morphologically diverged neighbors, neanderthal bones, neanderthals, sub saharan africans

*Anatomically modern humans interbred with more archaic hominin forms even before they migrated out of Africa, a UA-led team of researchers has found.*

It is now widely accepted that anatomically modern humans of the species Homo sapiens originated in Africa and eventually spread throughout the world. Ancient DNA recovered from fossil Neanderthal bones suggests they interbred with more archaic hominin forms once they had left their evolutionary cradle for the cooler climates of Eurasia, but whether they exchanged genetic material with other, now extinct archaic hominin varieties in Africa remained unclear.

In a paper published in the Proceedings of the National Academy of Sciences, or PNAS, a team led by Michael Hammer, an associate professor and research scientist with the UA’s Arizona Research Labs, provides evidence that anatomically modern humans were not so unique that they remained separate. (more…)

Six Million Years of African Savanna

By Guest PostAugust 6, 2011Environment, Scienceancient soil, anthony macharia, ape, ardipithecus, australopithecus, bipedalism, c3 pathway of photosynthesis, c4 photosynthesis, carbon isotope ratios in fossil soils, chemical isotopes, david kimutai korir, early human fossils, east african, environments, fossils of human ancestors, geochemist, geological past, homo, human ancestors, kenya wildlife service, michael bird, national science foundation, omo turkana basin of ethiopia and kenya, open grasslands, paleo shade proxy for soil temperature and woody cover, paleosols, paranthropus, prehistoric tree cover, ratio of rare carbon 13 to common carbon 12, richard lane, samuel andanje, savanna, savanna landscape, scattered trees, thure cerling, tropical landscapes, university of utah, vegetation chronologies of the awash valley of ethiopia, woody cover and hominin environments in the past 6 million years

*Open, grassy environments accompanied human evolution*

Scientists using chemical isotopes in ancient soil to measure prehistoric tree cover–in effect, shade–have found that grassy, tree-dotted savannas prevailed at most East African sites where human ancestors and their ape relatives evolved during the past six million years.

“We’ve been able to quantify how much shade was available in the geological past,” says University of Utah geochemist Thure Cerling, lead author of a paper titled “Woody cover and hominin environments in the past 6 million years” on the results in this week’s issue of the journal Nature. (more…)

Tag Archives: homo

Researchers Find Simple, Cheap Way to Increase Solar Cell Efficiency

International Research Team Close Human Evolution Gap with Discovery of 1.4 Million-Year-Old Fossil Human Hand Bone

Ancient Humans Were Mixing it Up

Six Million Years of African Savanna