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1.
PAPER CURRENT
Ephemeral plants mediate responses of ecosystem carbon exchange to increased precipitation in a temperate desert (2014)
Publication Date: 2014-11-24
Description: Publication date: 15 February 2015 Source:Agricultural and Forest Meteorology, Volume 201 Author(s): Gang Huang , Yan Li , Francisco M. Padilla The ecological consequences of increased precipitation on ecosystem carbon (C) exchange are gaining increasing concern, especially in the context of ongoing climate change in temperate deserts. In this study, a field manipulative experiment was conducted to assess the effects of increased precipitation and nitrogen (N) addition on net ecosystem C exchange (NEE) in a temperate desert in northwestern China during two years with contrasting precipitation patterns (2011 and 2012). Increased precipitation decreased ecosystem C release by nearly 50% in the wet year of 2011, whereas ecosystem C release was increased in the dry year of 2012 because of the disproportional stimulation of gross ecosystem productivity (GEP) and ecosystem respiration (ER) by increased precipitation. N addition had no impact on NEE because of the slight responses of both GEP and ER to N addition. During the wet year, most of the precipitation occurred during the growing season of ephemeral plants, which profoundly stimulated plant growth and led to a higher response of GEP than ER to increased precipitation. As a result, positive effects of increased precipitation on NEE occurred in this year. During the dry year, the majority of the precipitation fell post the ephemeral growing season and only a small increase in herb biomass was observed. However, the response of ER to increased precipitation was larger than that of GEP, leading to a more negative NEE in 2012, as compared to 2011. C release was thus stimulated by increased precipitation in 2012. Irrespective of precipitation treatment, N addition weakly decreased C release because of the negligible stimulation of GEP and ER, as well as the slight response of ephemeral biomass. The responses of NEE to increased precipitation showed no difference between interplant spaces and beneath the dominant shrubs because of the similar responses of plant growth, GEP and ER between sites. Overall, this study shows that the responses of NEE to projected increasing precipitation depend on the coupling of precipitation timing and plant growing season.
Print ISSN: 0168-1923
Electronic ISSN: 1873-2240
Topics: Geography , Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Physics
Published by Elsevier
2.
PAPER CURRENT
Differential temporal expression of milk miRNA during the lactation cycle of the marsupial tammar wallaby (Macropus eugenii) (2014)
Publication Date: 2014-11-24
Description: Background:Lactation is a key aspect of mammalian evolution for adaptation of various reproductive strategies along different mammalian lineages. Marsupials, such as tammar wallaby, adopted a short gestation and a relatively long lactation cycle, the newborn is immature at birth and significant development occurs postnatally during lactation. Continuous changes of tammar milk composition may contribute to development and immune protection of pouch young. Here, in order to address the putative contribution of newly identified secretory milk miRNA in these processes, high throughput sequencing of miRNAs collected from tammar milk at different time points of lactation was conducted. A comparative analysis was performed to find distribution of miRNA in milk and blood serum of lactating wallaby.Results:Results showed that high levels of miRNA secreted in milk and allowed the identification of differentially expressed milk miRNAs during the lactation cycle as putative markers of mammary gland activity and functional candidate signals to assist growth and timed development of the young. Comparative analysis of miRNA distribution in milk and blood serum suggests that milk miRNAs are primarily expressed from mammary gland rather than transferred from maternal circulating blood, likely through a new putative exosomal secretory pathway. In contrast, highly expressed milk miRNAs could be detected at significantly higher levels in neonate blood serum in comparison to adult blood, suggesting milk miRNAs may be absorbed through the gut of the young.Conclusion:The function of miRNA in mammary gland development and secretory activity has been proposed, but results from the current study also support a differential role of milk miRNA in regulation of development in the pouch young, revealing a new potential molecular communication between mother and young during mammalian lactation.
Electronic ISSN: 1471-2164
Topics: Biology
Published by BioMed Central
3.
PAPER CURRENT
Solvability of n th-order Lipschitz equations with nonlinear three-point boundary conditions (2014)
Publication Date: 2014-11-24
Description: In this paper, we investigate the solvability of nth-order Lipschitz equations y ( n ) = f ( x , y , y ′ , … , y ( n − 1 ) ) , x 1 ≤ x ≤ x 3 , with nonlinear three-point boundary conditions of the form k ( y ( x 2 ) , y ′ ( x 2 ) , … , y ( n − 1 ) ( x 2 ) ; y ( x 1 ) , y ′ ( x 1 ) , … , y ( n − 1 ) ( x 1 ) ) = 0 , g i ( y ( i ) ( x 2 ) , y ( i + 1 ) ( x 2 ) , … , y ( n − 1 ) ( x 2 ) ) = 0 , i = 0 , 1 , … , n − 3 , h ( y ( x 2 ) , y ′ ( x 2 ) , … , y ( n − 1 ) ( x 2 ) ; y ( x 3 ) , y ′ ( x 3 ) , … , y ( n − 1 ) ( x 3 ) ) = 0 , where n ≥ 3 , x 1 < x 2 < x 3 . By using the matching technique together with set-valued function theory, the existence and uniqueness of solutions for the problems are obtained. Meanwhile, as an application of our results, an example is given.MSC:34B10, 34B15.
Print ISSN: 1687-2762
Electronic ISSN: 1687-2770
Topics: Mathematics
Published by Springer
4.
PAPER CURRENT
On a minimal model for estimating climate sensitivity (2014)
Publication Date: 2014-11-24
Description: Publication date: 10 February 2015 Source:Ecological Modelling, Volume 297 Author(s): Gavin C. Cawley , Kevin Cowtan , Robert G. Way , Peter Jacobs , Ari Jokimäki In a recent issue of this journal, Loehle (2014) presents a “minimal model” for estimating climate sensitivity, identical to that previously published by Loehle and Scafetta (2011). The novelty in the more recent paper lies in the straightforward calculation of an estimate of transient climate response based on the model and an estimate of equilibrium climate sensitivity derived therefrom, via a flawed methodology. We demonstrate that the Loehle and Scafetta model systematically underestimates the transient climate response, due to a number of unsupportable assumptions regarding the climate system. Once the flaws in Loehle and Scafetta's model are addressed, the estimates of transient climate response and equilibrium climate sensitivity derived from the model are entirely consistent with those obtained from general circulation models, and indeed exclude the possibility of low climate sensitivity, directly contradicting the principal conclusion drawn by Loehle. Further, we present an even more parsimonious model for estimating climate sensitivity. Our model is based on observed changes in radiative forcings, and is therefore constrained by physics, unlike the Loehle model, which is little more than a curve-fitting exercise.
Print ISSN: 0304-3800
Topics: Biology
Published by Elsevier
5.
PAPER CURRENT
Volatile Concentrations in Olivine-Hosted Melt Inclusions from the Columbia River Flood Basalts and Associated Lavas of the Oregon Plateau: Implications for Magma Genesis (2014)
Publication Date: 2014-11-24
Description: Publication date: Available online 22 November 2014 Source:Chemical Geology Author(s): Joan A. Cabato , Christopher J. Stefano , Samuel B. Mukasa The volatile budgets and elemental compositions of primary magmas and their sources can be estimated through study of olivine-hosted melt inclusions in basaltic lavas, thereby providing insights about melting processes in the mantle. We report data on melt inclusions in 58 host-olivine crystals from seven basalt samples from the Columbia River Basalt (CRB) group in eastern Oregon and Washington, which have been analyzed for their major-oxide, trace-element and volatile (H2O, S, F, and Cl) concentrations to constrain the origin of this large igneous province. A wide range in H2O concentrations has been discovered, with the highest amount of 4.2wt% found in olivine grains from a lava flow in the Malheur Gorge area, which erupted several million years after the hypothesized initial impingement of the Yellowstone Hotspot against the lithosphere of the North American Plate. This H2O concentration and others in our Columbia River—Oregon Plateau sample suite are significantly higher than those observed in lavas from hotspots such as Hawaii (~0.8-0.9wt%) or in Mid-Ocean Ridge Basalts (MORBs) (~0.2wt%), and are comparable to those measured for the lavas in the Snake River Plain-Yellowstone volcanic corridor and in some island and continental arcs. Lavas considered to be of plume origin from the Picture Gorge basalts in the main-eruptive-stage of the CRB show H2O concentrations of up to 2.4 wt %, also significantly higher than values published previously for any plume-related volcanism. The highest H2O concentrations have been found most often in the least differentiated melt inclusions, indicating that these volatiles are not the result of differentiation at shallow levels in the crust. The enrichment of Ba relative to Th in many of the melt inclusions may indicate that volatiles in the CRB-OPB large igneous province have a subduction zone origin, which underscores the importance of flux melting in the generation of at least some of Earth’s large igneous provinces.
Print ISSN: 0009-2541
Topics: Chemistry and Pharmacology , Geosciences
Published by Elsevier
6.
PAPER CURRENT
Dynamics of larch bud moth populations: Application of Moran – Ricker models with time lag (2014)
Publication Date: 2014-11-24
Description: Publication date: 10 February 2015 Source:Ecological Modelling, Volume 297 Author(s): L.V. Nedorezov , D.L. Sadykova Modifications of Moran–Ricker model with time lags are applied for fitting of larch bud moth (Zeiraphera diniana Gn.) time series. Model parameters were estimated, and deviations between model trajectories and empirical time series were analyzed with various statistical tests. It was shown that some of considered models allowed obtaining rather good fitting. For estimated parameters asymptotic stable dynamic regimes were found: it is 9-year cycle (for model with time lag in four years), it is 18-year cycle (with close values of cycle coordinates for model with time lag in one year), or regime with complicated dynamics (for model with time lag in three years). Obtained results correspond to biological imagination about fluctuations of larch bud moth populations.
Print ISSN: 0304-3800
Topics: Biology
Published by Elsevier
7.
PAPER CURRENT
Nanosheet-assembling Hierarchical Zinc Stannate Microspheres for Enhanced Efficiency of Dye-Sensitized Solar Cells (2014)
Publication Date: 2014-11-24
Description: Publication date: 10 January 2015 Source:Electrochimica Acta, Volume 152 Author(s): Zhengdao Li , Yong Zhou , Hao Yang , Rantao Huang , Zhigang Zou Nanosheet-assembling hierarchical Zn2SnO4 microspheres (NHMSs) are synthesized via one-pot solvothermal route and used as photoanodes for dye-sensitized solar cells (DSSCs). An overall photoconversion efficiency of 3.43% has been achieved with this ternary metal oxide and structure, significantly higher than that derived from dispersed nanosheets (DNSs) electrode (2.06%). The hierarchical Zn2SnO4 microsphere structure is proven to be favorable for enhancement of overall dye-sensitized solar cells photoconversion efficiency via (1) the hierarchical Zn2SnO4 microspheres can function as efficient light scatters to enhance the light-harvesting efficiency; (2) intersectional contact with one another of the nanosheets of densely packed neighboring microspheres offers the transport channel for fast electron transport, avoiding the high resistance existing in the nanoparticle-based microspheres due to the relatively small interface resistance; (3) these spherical assemblies form large external pores for dye loading, at the same time, provide a “main trunk” for the quick electrolyte diffusion throughout the Zn2SnO4 layer in the film. Graphical abstract
Print ISSN: 0013-4686
Electronic ISSN: 1873-3859
Topics: Chemistry and Pharmacology , Physics
Published by Elsevier
8.
PAPER CURRENT
Software components for demand side integration at a container terminal (2014)
Publication Date: 2014-11-24
Description: Abstract Local energy management and demand response are established methods to raise energy efficiency, to lower the costs for energy supply, and even to help stabilizing the grid. With the emergence of E-Mobility in industrial enterprises the intelligent use of power demand draws significantly increased importance. Due to the time lag of actual energy usage by the vehicles and the energy demand from the grid for charging the batteries of these vehicles new possibilities for load shifting arise. These can be used to optimize the local energy demand curve, to react to RTP-pricing or to offer services to the grid like providing control reserve power. Support of information technology on consumer side is required to effectively make use of these possibilities. Based on a case study of the maritime container terminal altenwerder located in Hamburg and in reference to the electricity market reference architecture a software application is presented that extends the energy management of a flexible consumer with intelligent functions to control the energy demand.
Print ISSN: 1865-2034
Electronic ISSN: 1865-2042
Topics: Computer Science
Published by Springer
9.
PAPER CURRENT
Chemical Assembly of Zinc Oxide Aggregated Anodes on Plastic Substrates at Room Temperature for Flexible Dye-Sensitized Solar Cells (2014)
Publication Date: 2014-11-24
Description: Publication date: 10 January 2015 Source:Electrochimica Acta, Volume 152 Author(s): Shou-Yen Lin , Jih-Jen Wu A notable efficiency of 5.16% is achieved in the flexible dye-sensitized solar cell (DSSC) using a ZnO aggregated anode with a light scattering layer facilely fabricated on the indium tin oxide (ITO) coated-polyethylene terephthalate (PET) substrate. The ZnO aggregates composed of ZnO nanoparticles (NPs) and room-temperature (RT) grown nanostructures are chemically assembled on the ITO-PET substrate by the RT chemical treatment of the drop-cast ZnO NP layer on the substrate. The enhanced light scattering ability and superior electron transport property are measured in the ZnO aggregated matrix anode. A ZnO particle layer is further drop-cast on the ZnO aggregated matrix anode followed by another RT chemical treatment to form the light scattering layer. Dynamics of electron transport and recombination measurements indicate that an efficient electron collection is performed in the flexible ZnO anode fabricated free of high-temperature treatment and mechanical compression. Moreover, efficient photovoltaic performances are also monitored in both concave-downward and concave-upward bending configurations of the ZnO DSSCs, demonstrating the good flexibility of the ZnO nanostructured anodes. Graphical abstract
Print ISSN: 0013-4686
Electronic ISSN: 1873-3859
Topics: Chemistry and Pharmacology , Physics
Published by Elsevier
10.
PAPER CURRENT
A Novel Method for Decoding Any High-Order Hidden Markov Model (2014)
Publication Date: 2014-11-24
Description: This paper proposes a novel method for decoding any high-order hidden Markov model. First, the high-order hidden Markov model is transformed into an equivalent first-order hidden Markov model by Hadar’s transformation. Next, the optimal state sequence of the equivalent first-order hidden Markov model is recognized by the existing Viterbi algorithm of the first-order hidden Markov model. Finally, the optimal state sequence of the high-order hidden Markov model is inferred from the optimal state sequence of the equivalent first-order hidden Markov model. This method provides a unified algorithm framework for decoding hidden Markov models including the first-order hidden Markov model and any high-order hidden Markov model.
Print ISSN: 1026-0226
Electronic ISSN: 1607-887X
Topics: Mathematics
Published by Hindawi