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Articles 1 - 11 of 11
Full-Text Articles in Physical Sciences and Mathematics
Effects Of Elevated Carbon Dioxide And Increased Temperature On Methane And Nitrous Oxide Fluxes: Evidence From Field Experiments, Feike A. Dijlstra, Stephen A. Prior, G. Brett Renion, H. Allen Torbert, Hanqin Tian, Chaoqun (Crystal) Lu, Rodney T. Venterea
Effects Of Elevated Carbon Dioxide And Increased Temperature On Methane And Nitrous Oxide Fluxes: Evidence From Field Experiments, Feike A. Dijlstra, Stephen A. Prior, G. Brett Renion, H. Allen Torbert, Hanqin Tian, Chaoqun (Crystal) Lu, Rodney T. Venterea
Chaoqun (Crystal) Lu
Climate change could alter terrestrial ecosystems, which are important sources and sinks of the potent green-house gases (GHGs) nitrous oxide (N2O) and methane (CH4), in ways that either stimulate or decrease the magnitude and duration of global warming. Using manipulative field experiments, we assessed how N2O and CH4 soil fluxes responded to a rise in atmospheric carbon dioxide (CO2) concentration and to increased air temperature. Nitrous oxide and CH4 responses varied greatly among studied ecosystems. Elevated CO2 often stimulated N2O emissions in fertilized systems and CH4 emissions in wetlands, peatlands, and rice paddy fields; both effects were stronger in clayey …
Century-Scale Responses Of Ecosystem Carbon Storage And Flux To Multiple Environmental Changes In The Southern United States, Hanqin Tian, Guangsheng Chen, Chi Zang, Mingliang Liu, Ge Sun, Arthur Chappelka, Wei Ren, Xiaofeng Xu, Chaoqun Lu, Shufen Pan, Hua Chen, Dafeng Hui, Steven Mcnulty, Graeme Lockaby, Eric Vance
Century-Scale Responses Of Ecosystem Carbon Storage And Flux To Multiple Environmental Changes In The Southern United States, Hanqin Tian, Guangsheng Chen, Chi Zang, Mingliang Liu, Ge Sun, Arthur Chappelka, Wei Ren, Xiaofeng Xu, Chaoqun Lu, Shufen Pan, Hua Chen, Dafeng Hui, Steven Mcnulty, Graeme Lockaby, Eric Vance
Chaoqun (Crystal) Lu
Terrestrial ecosystems in the southern United States (SUS) have experienced a complex set of changes in climate, atmospheric CO2 concentration, tropospheric ozone (O3), nitrogen (N) deposition, and land-use and land-cover change (LULCC) during the past century. Although each of these factors has received attention for its alterations on ecosystem carbon (C) dynamics, their combined effects and relative contributions are still not well understood. By using the Dynamic Land Ecosystem Model (DLEM) in combination with spatially explicit, long-term historical data series on multiple environmental factors, we examined the century-scale responses of ecosystem C storage and flux to multiple environmental changes in …
A Reference-Free Algorithm For Computational Normalization Of Shotgun Sequencing Data, C. Titus Brown, Adina Howe, Qingpeng Zhang, Alexis B. Pyrkosz, Timothy H. Brom
A Reference-Free Algorithm For Computational Normalization Of Shotgun Sequencing Data, C. Titus Brown, Adina Howe, Qingpeng Zhang, Alexis B. Pyrkosz, Timothy H. Brom
Adina Howe
Deep shotgun sequencing and analysis of genomes, transcriptomes, amplified single-cell genomes, and metagenomes has enabled investigation of a wide range of organisms and ecosystems. However, sampling variation in short-read data sets and high sequencing error rates of modern sequencers present many new computational challenges in data interpretation. These challenges have led to the development of new classes of mapping tools and {\em de novo} assemblers. These algorithms are challenged by the continued improvement in sequencing throughput. We here describe digital normalization, a single-pass computational algorithm that systematizes coverage in shotgun sequencing data sets, thereby decreasing sampling variation, discarding redundant data, …
Multifactor Controls On Terrestrial N2o Flux Over North America From 1979 Through 2010, X. F. Xu, Hanqin Tian, G. S. Chen, M. L. Liu, Wei Ren, Chaoqun (Crystal) Lu, C. Zhang
Multifactor Controls On Terrestrial N2o Flux Over North America From 1979 Through 2010, X. F. Xu, Hanqin Tian, G. S. Chen, M. L. Liu, Wei Ren, Chaoqun (Crystal) Lu, C. Zhang
Chaoqun (Crystal) Lu
Nitrous oxide (N2O) is a potent greenhouse gas which also contributes to the depletion of stratospheric ozone (O3). However, the magnitude and underlying mechanisms for the spatiotemporal variations in the terrestrial sources of N2O are still far from certain. Using a process-based ecosystem model (DLEM – the Dynamic Land Ecosystem Model) driven by multiple global change factors, including climate variability, nitrogen (N) deposition, rising atmospheric carbon dioxide (CO2), tropospheric O3 pollution, N fertilizer application, and land conversion, this study examined the spatial and temporal variations in terrestrial N2O flux over North America and further attributed these variations to various driving …
Measuring Markers Of Liver Function Using A Micropatterned Paper Device Designed For Blood From A Fingerstick, Sarah J. Vella, Patrick Beattie, Rebecca Cademartiri, Anna Laromaine, Andres W. Martinez, Scott T. Phillips, Katherine A. Mirica, George M. Whitesides
Measuring Markers Of Liver Function Using A Micropatterned Paper Device Designed For Blood From A Fingerstick, Sarah J. Vella, Patrick Beattie, Rebecca Cademartiri, Anna Laromaine, Andres W. Martinez, Scott T. Phillips, Katherine A. Mirica, George M. Whitesides
Rebecca Cademartiri
This paper describes a paper-based microfluidic device that measures two enzymatic markers of liver function (alkaline phosphatase, ALP, and aspartate aminotransferase, AST) and total serum protein. A device consists of four components: (i) a top plastic sheet, (ii) a filter membrane, (iii) a patterned paper chip containing the reagents necessary for analysis, and (iv) a bottom plastic sheet. The device performs both the sample preparation (separating blood plasma from erythrocytes) and the assays; it also enables both qualitative and quantitative analysis of data. The data obtained from the paper-microfluidic devices show standard deviations in calibration runs and “spiked” standards that …
Food Benefit And Climate Warming Potential Of Nitrogen Fertilizer Uses In China, Hanqin Tian, Chaoqun (Crystal) Lu, Jerry Melillo, Wei Ren, Yao Huang, Xiaofeng Xu, Mingliang Liu, Chi Zhang, Guangsheng Chen, Shufen Pan, Jiyuan Liu, John Reilly
Food Benefit And Climate Warming Potential Of Nitrogen Fertilizer Uses In China, Hanqin Tian, Chaoqun (Crystal) Lu, Jerry Melillo, Wei Ren, Yao Huang, Xiaofeng Xu, Mingliang Liu, Chi Zhang, Guangsheng Chen, Shufen Pan, Jiyuan Liu, John Reilly
Chaoqun (Crystal) Lu
Chemical nitrogen (N) fertilizer has long been used to help meet the increasing food demands in China, the top N fertilizer consumer in the world. Growing concerns have been raised on the impacts of N fertilizer uses on food security and climate change, which is lack of quantification. Here we use a carbon–nitrogen (C–N) coupled ecosystem model, to quantify the food benefit and climate consequence of agronomic N addition in China over the six decades from 1949 to 2008. Results show that N fertilizer-induced crop yield and soil C sequestration had reached their peaks, while nitrous oxide (N2O) emission continued …
Effect Of Nitrogen Deposition On China's Terrestrial Carbon Uptake In The Context Of Multifactor Environmental Changes, Chaoqun (Crystal) Lu, Hanqin Tian, Mingliang Liu, Wei Ren, Xiaofeng Xu, Guangsheng Chen, Chi Zhang
Effect Of Nitrogen Deposition On China's Terrestrial Carbon Uptake In The Context Of Multifactor Environmental Changes, Chaoqun (Crystal) Lu, Hanqin Tian, Mingliang Liu, Wei Ren, Xiaofeng Xu, Guangsheng Chen, Chi Zhang
Chaoqun (Crystal) Lu
The amount of atmospheric nitrogen (N) deposited on the land surface has increased globally and by nearly five times in China from 1901 to 2005. Little is known about how elevated reactive N input has affected the carbon (C) sequestration capability of China's terrestrial ecosystems, largely due to the lack of reliable data on N deposition. Here we have used a newly developed data set of historical N deposition at a spatial resolution of 10 km × 10 km in combination with other gridded historical information on climate, atmospheric composition, land use, and land management practices to drive a process-based …
Contemporary And Projected Biogenic Fluxes Of Methane And Nitrous Oxide In North American Terrestrial Ecosystems, Hanqin Tian, Chaoqun (Crystal) Lu, Guangsheng Chen, Bo Tao, Shufen Pan, Stephen J. Del Grosso, Xiaofeng Xu, Lori Bruhwiler, Steven C. Wofsy, Eric A. Kort, Stephen A. Prior
Contemporary And Projected Biogenic Fluxes Of Methane And Nitrous Oxide In North American Terrestrial Ecosystems, Hanqin Tian, Chaoqun (Crystal) Lu, Guangsheng Chen, Bo Tao, Shufen Pan, Stephen J. Del Grosso, Xiaofeng Xu, Lori Bruhwiler, Steven C. Wofsy, Eric A. Kort, Stephen A. Prior
Chaoqun (Crystal) Lu
Accurately estimating biogenic methane (CH4) and nitrous oxide (N2O) fluxes in terrestrial ecosystems is critical for resolving global budgets of these greenhouse gases (GHGs) and continuing to mitigate climate warming. Here, we assess contemporary biogenic CH4 and N2O budgets and probable climate-change-related impacts on CH4 and N2O emissions in terrestrial North America. Multi-approach estimations show that, during 1990–2010, biogenic CH4 emissions ranged from 0.159 to 0.502 petagrams of carbon dioxide (CO2) equivalents per year (Pg CO2eq yr–1, where 1 Pg = 1 × 1015 g) and N2O emissions ranged from 0.802 to 1.016 Pg CO2eq yr–1, which offset 47–166% of …
Overview Of Fuel Ethanol Production And Distillers Grains, Kurt A. Rosentrater
Overview Of Fuel Ethanol Production And Distillers Grains, Kurt A. Rosentrater
Kurt A. Rosentrater
Modern societies face many challenges, including growing populations, increased demands for food, clothing, housing, consumer goods, and the concomitant raw materials required to produce all of these. Additionally, there is a growing need for energy, which is most easily met by use of fossil fuels (e.g., coal, natural gas, and petroleum). In 2008, the overall U.S. demand for energy was 99.3 x 1015 Btu (1.05 x 1014 MJ); 84% of this was supplied by fossil sources (U.S. EIA, 2009). Transportation fuels accounted for 28% of all energy consumed during this time, and nearly 97% of this came from fossil sources. …
Manufacturing Of Fuel Ethanol And Distillers Grains—Current And Evolving Processes, Kurt A. Rosentrater, Klein Ileleji, David B. Johnson
Manufacturing Of Fuel Ethanol And Distillers Grains—Current And Evolving Processes, Kurt A. Rosentrater, Klein Ileleji, David B. Johnson
Kurt A. Rosentrater
Before examining all of the different possible uses of distillers dried grains with solubles (DDGS), a discussion regarding ethanol and DDGS production methods is warranted. This chapter will cover current production processes and some of the new practices that have been developed and are being adopted at plants, including front-end fractionation and back-end fractionation. Additionally, standard coproduct definitions will be discussed, as they govern the marketing and sales of these materials.
Toward A Scientific Understanding Of Ddgs, Keshun Liu, Kurt A. Rosentrater
Toward A Scientific Understanding Of Ddgs, Keshun Liu, Kurt A. Rosentrater
Kurt A. Rosentrater
Recently, many people have asked what the fuel ethanol industry is going to do about the growing piles of nonfermented leftovers. Actually this question has been around for quite some time. As early as the 1940s, one report stated that "Grain distillers have developed equipment and an attractive market for their recovered grains" (Boruff, 1947), while another report described that "Distillers are recovering, drying, and marketing their destarched grain stillage as distillers dried grains and dried solubles" (Boruff, 1952). So it appears that a viable solution had already been developed as far back as the 1940s. And by the early …