The separation of the base flow component from a varying streamflow hydrograph is called "hydrograph analysis." In this study, two digital filter based separation modules, the BFLOW and Eckhardt ...filters, were incorporated into the Web based Hydrograph Analysis Tool (WHAT) system. A statistical component was also developed to provide fundamental information for flow frequency analysis and time series analysis. The Web Geographic Information System (GIS) version of the WHAT system accesses and uses U.S. Geological Survey (USGS) daily streamflow data from the USGS web server. The results from the Eckhardt filter method were compared with the results from the BFLOW filter method that was previously validated, since measured base flow data were not available for this study. Following validation, the two digital filter methods in the WHAT system were run for 50 Indiana gaging stations. The Nash-Sutcliffe coefficient values comparing the results of the two digital filter methods were over 0.91 for all 50 gaging stations, suggesting the filtered base flow using the Eckhardt filter method will typically match measured base flow. Manual separation of base flow from streamflow can lead to inconsistency in the results, while the WHAT system provides consistent results in less than a minute. Although base flow separation algorithms in the WHAT system cannot consider reservoir release and snowmelt that can affect stream hydrographs, the Web based WHAT system provides an efficient tool for hydrologic model calibration and validation. The base flow information from the WHAT system can also play an important role for sustainable ground water and surface water exploitation, including irrigation and industrial uses, and estimation of pollutant loading from both base flow and direct runoff. Thus, best management practices can be appropriately applied to reduce and intercept pollutant leaching if base flow contributes significant amounts of pollutants to the stream. This Web GIS based system also demonstrates how remote, distributed resources can be shared through the Internet using Web programming.
The ideotype approach has been used in breeding programs at the International Rice Research Institute (IRRI) and in China to improve rice yield potential. First-generation new plant type (NPT) lines ...developed from tropical japonica at IRRI did not yield well because of limited biomass production and poor grain filling. Progress has been made in second-generation NPT lines developed by crossing elite indica with improved tropical japonica. Several second-generation NPT lines outyielded the first-generation NPT lines and indica check varieties. China's “super” rice breeding project has developed many F
1 hybrid varieties using a combination of the ideotype approach and intersubspecific heterosis. These hybrid varieties produced grain yield of 12
t
ha
−1 in on-farm demonstration fields, 8–15% higher than the hybrid check varieties. The success of China's “super” hybrid rice was partially the result of assembling the good components of IRRI's NPT design in addition to the use of intersubspecific heterosis. For example, both designs focused on large panicle size, reduced tillering capacity, and improved lodging resistance. More importantly, improvement in plant type design was achieved in China's “super” hybrid rice by emphasizing the top three leaves and panicle position within a canopy in order to meet the demand of heavy panicles for a large source supply. The success of “super” hybrid rice breeding in China and progress in NPT breeding at IRRI suggest that the ideotype approach is effective for breaking the yield ceiling of an irrigated rice crop.
Recent research in nitrogen exchange with the atmosphere has separated research communities according to N form. The integrated perspective needed to quantify the net effect of N on greenhouse-gas ...balance is being addressed by the NitroEurope Integrated Project (NEU). Recent advances have depended on improved methodologies, while ongoing challenges include gas–aerosol interactions, organic nitrogen and N
2 fluxes. The NEU strategy applies a 3-tier Flux Network together with a Manipulation Network of global-change experiments, linked by common protocols to facilitate model application. Substantial progress has been made in modelling N fluxes, especially for N
2O, NO and bi-directional NH
3 exchange. Landscape analysis represents an emerging challenge to address the spatial interactions between farms, fields, ecosystems, catchments and air dispersion/deposition. European up-scaling of N fluxes is highly uncertain and a key priority is for better data on agricultural practices. Finally, attention is needed to develop N flux verification procedures to assess compliance with international protocols.
Current N research is separated by form; the challenge is to link N components, scales and issues.
CO2 sensing is of great societal implications, as CO2 is a component of gas mixtures from many natural and anthropogenic processes with huge impacts on globe climate and human well-being. Herein we ...report a CO2 assay scheme over a wide concentration range, utilizing a fluorogen with an aggregation-induced emission feature and a liquid with tunable polarity and viscosity. The CO2 sensing process is specific, quantitative, and interferent tolerant.
We report on a wearable tear bioelectronic platform, integrating a microfluidic electrochemical detector into an eyeglasses nose-bridge pad, for non-invasive monitoring of key tear biomarkers. The ...alcohol-oxidase (AOx) biosensing fluidic system allowed real-time tear collection and direct alcohol measurements in stimulated tears, leading to the first wearable platform for tear alcohol monitoring. Placed outside the eye region this fully wearable tear-sensing platform addresses drawbacks of sensor systems involving direct contact with the eye as the contact lenses platform. Integrating the wireless electronic circuitry into the eyeglasses frame thus yielded a fully portable, convenient-to-use fashionable sensing device. The tear alcohol sensing concept was demonstrated for monitoring of alcohol intake in human subjects over multiple drinking courses, displaying good correlation to parallel BAC measurements. We also demonstrate for the first time the ability to monitor tear glucose outside the eye and the utility of wearable devices for monitoring vitamin nutrients in connection to enzymatic flow detector and rapid voltammetric scanning, respectively. These developments pave the way to build an effective eyeglasses system capable of chemical tear analysis.
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•Wearable fluidic tears biosensor and wireless circuitry integrated into eyeglasses for non-invasive biomarker monitoring.•Wearable tear sensing platform placed outside the eye region mitigates drawbacks of systems requiring direct eye contact.•Real-time collection and direct measurements of stimulated tears allow the first wearable tear alcohol monitoring platform.
Perfluorooctane sulfonate (PFOS) and related substances are persistent, bioaccumulative, and toxic, and thus of substantial environmental concern. PFOS is an essential photolithographic chemical in ...the semiconductor industry with no substitutes yet identified. The industry seeks effective treatment technologies. The feasibility of using reverse osmosis (RO) membranes for treating semiconductor wastewater containing PFOS has been investigated. Commercial RO membranes were characterized in terms of permeability, salt rejection, scanning electron microscopy (SEM), transmission electron microscopy (TEM), and membrane surface zeta potential (streaming potential measurements). Filtration tests were performed to determine the membrane flux and PFOS rejection. Over a wide range of feed concentrations (0.5 − 1500 ppm), the RO membranes generally rejected 99% or more of the PFOS. Rejection was better for tighter membranes, but was not affected by membrane zeta potential. Flux decreased with increasing PFOS concentration. While the flux reduction was severe for a loose RO membrane probably due to its higher initial flux, very stable flux was maintained for tighter membranes. At a very high feed concentration (about 500 ppm), all the membranes exhibited an identical stable flux. Isopropyl alcohol, present in some semiconductor wastewaters, had a detrimental effect on membrane flux. Where present it needs to be removed from the wastewater prior to using RO membranes.
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