The Cuatro Ciénegas Basin (CCB) is a rare oasis in the Chihuahuan Desert in the state of Coahuila, Mexico. It has a biological endemism similar to that of the Galapagos Islands, and its spring-fed ecosystems have very low nutrient content (nitrogen or phosphorous) and are dominated by diverse microbialites. Thus, it has proven to be a distinctive opportunity for the field of astrobiology, as th...

Advanced oxidation processes (AOPs) have led the way in the treatment of aqueous waste and are rapidly becoming the chosen technology for many applications. In this paper, COD reduction potential of leather tanning industry wastewaters by Electro-Fenton (EF) oxidation, as one of the AOPs, was experimentally evaluated. The wastewater sample was taken from an outlet of an equalization basin in a ...

We report the reproducible first-principles folding of the 40 amino-acid, three-helix headpiece of the HIV accessory protein in a recently developed all-atom free-energy force field. Six of 20 simulations using an adapted basin-hopping method converged to better than 3 A backbone rms deviation to the experimental structure. Using over 60 000 low-energy conformations of this protein, we construc...

The lunar semidiurnal influence is already known for tidal rivers. The moon also influences inland rivers at a monthly scale through precipitation. We show that, for some non-tidal rivers, with special geological conditions, the lunar semidiurnal tidal oscillation can be detected. The moon has semidiurnal tidal influence on groundwater, which will then export it to streamflow. Long time series ...

East Asian summer monsoon (EASM) precipitation received by northern China over the past 800 thousand years (ky) is characterized by dominant 100-ky periodicity, mainly attributed to CO2 and Northern Hemisphere insolation-driven ice sheet forcing. We established an EASM record in the Late Miocene from lacustrine sediments in the Qaidam Basin, northern China, which appears to exhibit a dominant 1...

Biomolecules often undergo large-amplitude motions when they bind or release other molecules. Unlike macroscopic machines, these biomolecular machines can partially disassemble (unfold) and then reassemble (fold) during such transitions. Here we put forward a minimal structure-based model, the "multiple-basin model," that can directly be used for molecular dynamics simulation of even very large...

The objective of this study is to provide estimates of price elasticities of irrigation water demands in Zhangye Basin (ZB), an inland river basin in China, with the most recent data and to compare the values of marginal product (VMPs) of water to the prices of water farmers are currently paying. With a set of village and household survey data collected in 2009 and 2014, household fixed effects...

Track and cladistic biogeographic analyses based on insect taxa are used as a framework to interpret patterns of the Latin American and Caribbean entomofauna by identifying biogeographic areas on the basis of endemicity and arranging them hierarchically in a system of regions, subregions, dominions, and provinces. The Nearctic region, inhabited by Holarctic insect taxa, comprises five provinces...