Tag Archives: photosynthesis

Artificial Forest for Solar Water-Splitting

By Guest PostJune 14, 2013Environmentartificial forest, atmospheric carbon dioxide, berkeley lab, bin liu, carbon neutral, chloroplasts, chong liu, fuel conversion, green plants, hao ming chen, hydrogen generating photocathode, jinyao tang, nanowire heterostructures, natural photosynthesis, ohmic contact, oxidation half reactions, oxygen molecules, peidong yang, photosynthesis, reduction, renewable energy, silicon, solar, solar water splitting, stable semiconductors, titanium oxide, z scheme

Berkeley Lab Researchers Report First Fully Integrated Artificial Photosynthesis Nanosystem

In the wake of the sobering news that atmospheric carbon dioxide is now at its highest level in at least three million years, an important advance in the race to develop carbon-neutral renewable energy sources has been achieved. Scientists with the U.S. Department of Energy (DOE)’s Lawrence Berkeley National Laboratory (Berkeley Lab) have reported the first fully integrated nanosystem for artificial photosynthesis. While “artificial leaf” is the popular term for such a system, the key to this success was an “artificial forest.”

“Similar to the chloroplasts in green plants that carry out photosynthesis, our artificial photosynthetic system is composed of two semiconductor light absorbers, an interfacial layer for charge transport, and spatially separated co-catalysts,” says Peidong Yang, a chemist with Berkeley Lab’s Materials Sciences Division, who led this research. “To facilitate solar water- splitting in our system, we synthesized tree-like nanowire heterostructures, consisting of silicon trunks and titanium oxide branches. Visually, arrays of these nanostructures very much resemble an artificial forest.” (more…)

Dead Forests Release Less Carbon Into Atmosphere Than Expected

By Guest PostMarch 25, 2013Environmentalaska, atmosphere, boulder, carbon, carbon dioxide, climate, climate change, CO2, david moore, dead forests release, dendroctonus ponderosae, double whammy, earth, greenhouse gas, Mexico, mountain pine beetles, NASA, nicole trahan, niwot ridge, North America, organic compounds, outbreaks, photosynthesis, pine beetle outbreaks, russell monson, soil microbes, surface, university of arizona, university of colorado, warmer conditions

Billions of trees killed in the wake of mountain pine beetle infestations, ranging from Mexico to Alaska, have not resulted in a large spike in carbon dioxide released into the atmosphere, contrary to predictions, a UA-led study has found.

Massive tree die-offs release less carbon into the atmosphere than previously thought, new research led by the University of Arizona suggests.

Across the world, trees are dying in increasing numbers, most likely in the wake of a climate changing toward drier and warmer conditions, scientists suspect. In western North America, outbreaks of mountain pine beetles (Dendroctonus ponderosae) have killed billions of trees from Mexico to Alaska over the last decade. (more…)

How to Thrive in Battery Acid and Among Toxic Metals

By Guest PostMarch 9, 2013Environment, Scienceandreas weber, archaebacteria, bacteria, battery acid, biofuel production, biotechnology, decoded genetic information, dusseldorf, effects of toxins, eukaryote, eukaryotic microorganisms, evolution, extraterrestrial creature, extreme environment, galdieria, galdieria sulphuraria, genes from bacteria, genome of extremophile, gerald schoenknecht, Germany, heinrich heine universitat, horizontal gene transfer, hot springs, martin lercher, matt kane, movie alien, national science foundation, oil producing algae, oklahoma state university, photosynthesis, red alga, thrive, toxic metals, yellowstone national park

Genome of “extremophile” red alga offers insights

In the movie Alien, the title character is an extraterrestrial creature that can survive brutal heat and resist the effects of toxins.

In real life, organisms with similar traits exist, such as the “extremophile” red alga Galdieria sulphuraria.

In hot springs in Yellowstone National Park, Galdieria uses energy from the sun to produce sugars through photosynthesis. (more…)

Golden Algae: They Hunt, They Kill, They Cheat

By Guest PostJanuary 23, 2013Scienceachilles heel, basic functioning, behavior, carnivorous plants, cheaters, cheating behavior, chemical warfare, chimpanzees, cuckoos, diatoms, ecology of microbes, energy from sunlight, freshwater environment, giant kelp, golden algae, humans, jeremiah hackett, multicellular organism, photosynthesis, phytoplankton, predator; alternative explanation, prymnesium parvum, rattlesnake venom, single celled algae, species of algae, toxic alga, toxic algae, toxic algal blooms, toxic cells, toxic counterparts, toxic population, toxin, university of arizona, us waters, venus fly trap, william driscoll

Cheating is a behavior not limited to humans, animals and plants. Even microscopically small, single-celled algae do it, a team of UA researchers has discovered.

Humans do it, chimpanzees do it, cuckoos do it – cheating to score a free ride is a well-documented behavior by many animals, even plants. But microscopically small, single-celled algae? Yes, they do it too, biologists with the University of Arizona’s department of ecology and evolutionary biology have discovered.

“There are cheaters out there that we didn’t know of,” said William Driscoll, lead author of a research report on the topic who studied an environmentally devastating toxic alga that is invading U.S. waters as part of his doctoral research in the lab of Jeremiah Hackett, an assistant professor of ecology and evolutionary biology. (more…)

How Computers Push on the Molecules They Simulate

By Guest PostJanuary 9, 2013Scienceacceleration, albert einstein, algorithm, analytical results, artifacts, atoms and molecules, behavior, Berkeley, berkeley lab, calculation, california, california institute, chemical fuel, collide, computer method, conserve energy, david sivak, digital representation, digitize time, dna repair, driving force, effective friction, energy dense, equation, error, finite time steps, fluid, french physicist, gavin crooks, john chodera, langevin dynamics, model brownian motion, modeling molecular system, modern computer, molecular machines, molecular scale motion, molecule, momentum, natural system, nonequilibrium driving force, nonequilibrium statistical mechanics, particle, passage of time, paul langevin, photosynthesis, pollen grain, qb3, quantitative biosciences, quantum mechanics, real world, simulation, source, tenacious errors, theoretical method, thermal energy, toy models, university, velocity, water, water molecules

Berkeley Lab bioscientists and their colleagues decipher a far-reaching problem in computer simulations

Because modern computers have to depict the real world with digital representations of numbers instead of physical analogues, to simulate the continuous passage of time they have to digitize time into small slices. This kind of simulation is essential in disciplines from medical and biological research, to new materials, to fundamental considerations of quantum mechanics, and the fact that it inevitably introduces errors is an ongoing problem for scientists.

Scientists at the U.S. Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab) have now identified and characterized the source of tenacious errors and come up with a way to separate the realistic aspects of a simulation from the artifacts of the computer method. The research was done by David Sivak and his advisor Gavin Crooks in Berkeley Lab’s Physical Biosciences Division and John Chodera, a colleague at the California Institute of Quantitative Biosciences (QB3) at the University of California at Berkeley. The three report their results in Physical Review X. (more…)

Blades and Clades: Why Some Grasses Got Better Photosynthesis

By Guest PostDecember 25, 2012Scienceagriculture, anatomical difference, anatomical traits, ancestral state reconstruction, atmospheric co2, bep clade, blades, bundle sheath cells, c3, c4, c4 evolution, cellular anatomy, clades, david chatelet, dry condition, erika edwards, evolutionary time scale, evolutionary tree, genetic data, grasses, laura garrison, lineage, mesophyll cells, pacmad clade, pascal antoine christin, photosynthesis, physiology

Two groups — clades — of grasses that once had a common ancestry diverged. The PACMAD clade was predisposed to evolve a more efficient “C4” means of photosynthesis than grasses in the BEP clade. In a new study in the Proceedings of the National Academy of Sciences, a Brown-led team pinpoints the anatomical differences between the clades that led to the PACMAD’s tendency toward C4.

PROVIDENCE, R.I. [Brown University] — Even on the evolutionary time scale of tens of millions of years there is such a thing as being in the right shape at the right time. An anatomical difference in the ability to seize the moment, according to a study led by Brown University biologists, explains why more species in one broad group, or clade, of grasses evolved a more efficient means of photosynthesis than species in another clade. (more…)

Crowdsourcing Site Compiles New Sign Language for Math and Science

By Guest PostDecember 11, 2012Education, Scienceamerican sign language, asl, asl stem forum, byte, caroline solomon, crowdsourcing, dictionary, eukaryote, Europe, google corp, harry lang, kyle rector, lexicon of science, light year, multimedia feature, national science foundation, new york times, organism, photosynthesis, raja kushalnagar, richard ladner, science signs lexicon, sign language, united states, university, urban dictionary, Washington, Wikipedia

A multimedia feature published this week in the New York Times, “Pushing Science’s Limits in Sign Language Lexicon,” outlines efforts in the United States and Europe to develop sign language versions of specialized terms used in science, technology, engineering and mathematics.

The article shares newly defined signs for terms like “light-year,” “organism” and “photosynthesis.” It also describes a successful crowdsourcing effort started at the University of Washington in 2008 that lets members of the deaf and hard-of-hearing community build their own guide to the evolving lexicon of science.

“It’s not a dictionary,” explained Richard Ladner, a UW professor of computer science and engineering. “The goal of the forum is to be constantly changing, a reflection of the current use.” (more…)

Small Organisms Could Dramatically Impact World’s Climate

By Guest PostOctober 26, 2012Environment21st century, atmospheric, carbon, carbon dioxide, christopher klausmeier, climate change, colin kremer, cycle, david garrison, diversity, element, elena litchman, equatorial water, evolutionary adaptation, food chain, global climate, impact, level, marine microorganism, michigan, mridul thomas, nitrogen, ocean, ocean floor, organism, phosphorous, photosynthesis, phytoplankton, population, science express, state university, temperature, tropical water, warmer

EAST LANSING, Mich. — Warmer oceans in the future could significantly alter populations of phytoplankton, tiny organisms that could have a major impact on climate change.

In the current issue of Science Express, Michigan State University researchers show that by the end of the 21st century, warmer oceans will cause populations of these marine microorganisms to thrive near the poles and may shrink in equatorial waters. Since phytoplankton play a key role in the food chain and the world’s cycles of carbon, nitrogen, phosphorous and other elements, a drastic drop could have measurable consequences. (more…)