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Elyse D. Bernard Kathy C. Nguyen Maria C. DeRosa Azam F. Tayabali Rocio Aranda-Rodriguez 《Analytical biochemistry》2015
A multiplexing bead-based platform provides an approach for the development of assays targeting specific analytes for biomonitoring and biosensing applications. Multi-Analyte Profiling (xMAP) assays typically employ a sandwich-type format using antibodies for the capture and detection of analytes of interest, and the system permits the simultaneous quantitation of multiple targets. In this study, an aptamer/antibody assay for the detection of C-reactive protein (CRP) was developed. CRP is an acute phase marker of inflammation whose elevated basal levels are correlated with an increased risk for a number of pathologies. For this assay, an RNA aptamer that binds CRP was conjugated to beads to act as the capture agent. Biotinylated anti-CRP antibody coupled to fluorescently labeled streptavidin was used for quantification of CRP. The detection limit of the CRP assay was 0.4 mg/L in diluted serum. The assay was then used to detect spiked CRP samples in the range of 0.4 to 10 mg/L in diluted serum with acceptable recoveries (extrapolated values of 70–130%), including that of a certified reference material (129% recovery). The successful incorporation of the CRP aptamer into this platform demonstrates that the exploration of other aptamer–target systems could increase the number of analytes measurable using xMAP-type assays. 相似文献
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Priority threat management of invasive animals to protect biodiversity under climate change 下载免费PDF全文
Jennifer Firn Ramona Maggini Iadine Chadès Sam Nicol Belinda Walters Andy Reeson Tara G. Martin Hugh P. Possingham Jean‐Baptiste Pichancourt Rocio Ponce‐Reyes Josie Carwardine 《Global Change Biology》2015,21(11):3917-3930
Climate change is a major threat to global biodiversity, and its impacts can act synergistically to heighten the severity of other threats. Most research on projecting species range shifts under climate change has not been translated to informing priority management strategies on the ground. We develop a prioritization framework to assess strategies for managing threats to biodiversity under climate change and apply it to the management of invasive animal species across one‐sixth of the Australian continent, the Lake Eyre Basin. We collected information from key stakeholders and experts on the impacts of invasive animals on 148 of the region's most threatened species and 11 potential strategies. Assisted by models of current distributions of threatened species and their projected distributions, experts estimated the cost, feasibility, and potential benefits of each strategy for improving the persistence of threatened species with and without climate change. We discover that the relative cost‐effectiveness of invasive animal control strategies is robust to climate change, with the management of feral pigs being the highest priority for conserving threatened species overall. Complementary sets of strategies to protect as many threatened species as possible under limited budgets change when climate change is considered, with additional strategies required to avoid impending extinctions from the region. Overall, we find that the ranking of strategies by cost‐effectiveness was relatively unaffected by including climate change into decision‐making, even though the benefits of the strategies were lower. Future climate conditions and impacts on range shifts become most important to consider when designing comprehensive management plans for the control of invasive animals under limited budgets to maximize the number of threatened species that can be protected. 相似文献
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The Contribution of Agriculture,Forestry and other Land Use activities to Global Warming, 1990–2012 下载免费PDF全文
Francesco N. Tubiello Mirella Salvatore Alessandro F. Ferrara Jo House Sandro Federici Simone Rossi Riccardo Biancalani Rocio D. Condor Golec Heather Jacobs Alessandro Flammini Paolo Prosperi Paola Cardenas‐Galindo Josef Schmidhuber Maria J. Sanz Sanchez Nalin Srivastava Pete Smith 《Global Change Biology》2015,21(7):2655-2660
We refine the information available through the IPCC AR5 with regard to recent trends in global GHG emissions from agriculture, forestry and other land uses (AFOLU), including global emission updates to 2012. Using all three available AFOLU datasets employed for analysis in the IPCC AR5, rather than just one as done in the IPCC AR5 WGIII Summary for Policy Makers, our analyses point to a down‐revision of global AFOLU shares of total anthropogenic emissions, while providing important additional information on subsectoral trends. Our findings confirm that the share of AFOLU emissions to the anthropogenic total declined over time. They indicate a decadal average of 28.7 ± 1.5% in the 1990s and 23.6 ± 2.1% in the 2000s and an annual value of 21.2 ± 1.5% in 2010. The IPCC AR5 had indicated a 24% share in 2010. In contrast to previous decades, when emissions from land use (land use, land use change and forestry, including deforestation) were significantly larger than those from agriculture (crop and livestock production), in 2010 agriculture was the larger component, contributing 11.2 ± 0.4% of total GHG emissions, compared to 10.0 ± 1.2% of the land use sector. Deforestation was responsible for only 8% of total anthropogenic emissions in 2010, compared to 12% in the 1990s. Since 2010, the last year assessed by the IPCC AR5, new FAO estimates indicate that land use emissions have remained stable, at about 4.8 Gt CO2 eq yr?1 in 2012. Emissions minus removals have also remained stable, at 3.2 Gt CO2 eq yr?1 in 2012. By contrast, agriculture emissions have continued to grow, at roughly 1% annually, and remained larger than the land use sector, reaching 5.4 Gt CO2 eq yr?1 in 2012. These results are useful to further inform the current climate policy debate on land use, suggesting that more efforts and resources should be directed to further explore options for mitigation in agriculture, much in line with the large efforts devoted to REDD+ in the past decade. 相似文献
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Kim Y Mosier NS Ladisch MR Pallapolu VR Lee YY Garlock R Balan V Dale BE Donohoe BS Vinzant TB Elander RT Falls M Sierra R Holtzapple MT Shi J Ebrik MA Redmond T Yang B Wyman CE Warner RE 《Bioresource technology》2011,102(24):11089-11096
Feedstock quality of switchgrass for biofuel production depends on many factors such as morphological types, geographic origins, maturity, environmental and cultivation parameters, and storage. We report variability in compositions and enzymatic digestion efficiencies for three cultivars of switchgrass (Alamo, Dacotah and Shawnee), grown and harvested at different locations and seasons. Saccharification yields of switchgrass processed by different pretreatment technologies (AFEX, dilute sulfuric acid, liquid hot water, lime, and soaking in aqueous ammonia) are compared in regards to switchgrass genotypes and harvest seasons. Despite its higher cellulose content per dry mass, Dacotah switchgrass harvested after wintering consistently gave a lower saccharification yield than the other two varieties harvested in the fall. The recalcitrance of upland cultivars and over-wintered switchgrass may require more severe pretreatment conditions. We discuss the key features of different pretreatment technologies and differences in switchgrass cultivars and harvest seasons on hydrolysis performance for the applied pretreatment methods. 相似文献
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Pallapolu VR Lee YY Garlock RJ Balan V Dale BE Kim Y Mosier NS Ladisch MR Falls M Holtzapple MT Sierra-Ramirez R Shi J Ebrik MA Redmond T Yang B Wyman CE Donohoe BS Vinzant TB Elander RT Hames B Thomas S Warner RE 《Bioresource technology》2011,102(24):11115-11120
The objective of this work is to investigate the effects of cellulase loading and β-glucosidase supplementation on enzymatic hydrolysis of pretreated Dacotah switchgrass. To assess the difference among various pretreatment methods, the profiles of sugars and intermediates were determined for differently treated substrates. For all pretreatments, 72 h glucan/xylan digestibilities increased sharply with enzyme loading up to 25 mg protein/g-glucan, after which the response varied depending on the pretreatment method. For a fixed level of enzyme loading, dilute sulfuric acid (DA), SO2, and Lime pretreatments exhibited higher digestibility than the soaking in aqueous ammonia (SAA) and ammonia fiber expansion (AFEX). Supplementation of Novozyme-188 to Spezyme-CP improved the 72 h glucan digestibility only for the SAA treated samples. The effect of β-glucosidase supplementation was discernible only at the early phase of hydrolysis where accumulation of cellobiose and oligomers is significant. Addition of β-glucosidase increased the xylan digestibility of alkaline treated samples due to the β-xylosidase activity present in Novozyme-188. 相似文献
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Maria de Jesus B. Cavalcante Jacques Escoute Jean Paul Madeira Rocio E. Romero Michel R. Nicole Luis C. Oliveira Chantal Hamelin Marc Lartaud Jean L. Verdeil 《Tropical plant biology》2011,4(2):134-143
Globally, the banana plant (Musa spp) is the fourth most important crop after rice, wheat and corn (based on production in tons). It is cultivated in more than 100 tropical and subtropical countries, mainly by small producers and is a fundamental food source for millions of people. Black leaf streak disease (BLSD), caused by Mycosphaerella fijiensis Morelet (sexual phase) or Paracercospora fijiensis (Morelet) Deighton (asexual phase), is the main disease affecting the world??s banana culture. This disease has a wide geographical distribution accounting for losses exceeding 50% of global banana production. We conducted a comparative histocytological study on the kinetics of the infection process using three banana genotypes with phenotypes that differ in resistance to BLSD: Grand Naine (Susceptible), Pisang Madu (Partially Resistant) and Calcutta 4 (Resistant). Experiments were conducted under controlled conditions with the objective of characterizing the cellular interaction processes between M. fijiensis and Musa acuminata. Conidia germination occurred 24 hours after inoculation. Germination rates were high (97%) and there were no significant differences between the three genotypes (P?>?0.147). The Peroxidase enzyme and H2O2 were associated with a hypersensitivity-like reaction in the resistant genotype Calcutta 4, indicating a possible role of the enzyme or its product as defense mechanisms against M. fijiensis in banana plants. 相似文献
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Low levels of the Survival Motor Neuron (SMN) protein produce Spinal Muscular Atrophy (SMA), a severe monogenetic disease in infants characterized by muscle weakness and impaired synaptic transmission. We report here severe structural and functional alterations in the organization of the organelles and the cytoskeleton of motor nerve terminals in a mouse model of SMA. The decrease in SMN levels resulted in the clustering of synaptic vesicles (SVs) and Active Zones (AZs), reduction in the size of the readily releasable pool (RRP), and the recycling pool (RP) of synaptic vesicles, a decrease in active mitochondria and limiting of neurofilament and microtubule maturation. We propose that SMN is essential for the normal postnatal maturation of motor nerve terminals and that SMN deficiency disrupts the presynaptic organization leading to neurodegeneration. 相似文献