159 research outputs found
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Monte Carlo control loops for cosmic shear cosmology with DES Year 1 data
Weak lensing by large-scale structure is a powerful probe of cosmology and of the dark universe. This cosmic shear technique relies on the accurate measurement of the shapes and redshifts of background galaxies and requires precise control of systematic errors. Monte Carlo control loops (MCCL) is a forward modeling method designed to tackle this problem. It relies on the ultra fast image generator (UFig) to produce simulated images tuned to match the target data statistically, followed by calibrations and tolerance loops. We present the first end-to-end application of this method, on the Dark Energy Survey (DES) Year 1 wide field imaging data. We simultaneously measure the shear power spectrum
C
ℓ
and the redshift distribution
n
(
z
)
of the background galaxy sample. The method includes maps of the systematic sources, point spread function (PSF), an approximate Bayesian computation (ABC) inference of the simulation model parameters, a shear calibration scheme, and a fast method to estimate the covariance matrix. We find a close statistical agreement between the simulations and the DES Y1 data using an array of diagnostics. In a nontomographic setting, we derive a set of
C
ℓ
and
n
(
z
)
curves that encode the cosmic shear measurement, as well as the systematic uncertainty. Following a blinding scheme, we measure the combination of
Ω
m
,
σ
8
, and intrinsic alignment amplitude
A
IA
, defined as
S
8
D
IA
=
σ
8
(
Ω
m
/
0.3
)
0.5
D
IA
, where
D
IA
=
1
−
0.11
(
A
IA
−
1
)
. We find
S
8
D
IA
=
0.89
5
+
0.054
−
0.039
, where systematics are at the level of roughly 60% of the statistical errors. We discuss these results in the context of earlier cosmic shear analyses of the DES Y1 data. Our findings indicate that this method and its fast runtime offer good prospects for cosmic shear measurements with future wide-field surveys
Enhancing methane production from lignocellulosic biomass by combined steam‑explosion pretreatment and bioaugmentation with cellulolytic bacterium Caldicellulosiruptor bescii
Background: Biogas production from lignocellulosic biomass is generally considered to be challenging due to the recalcitrant nature of this biomass. In this study, the recalcitrance of birch was reduced by applying steam-explosion (SE) pretreatment (210 °C and 10 min). Moreover, bioaugmentation with the cellulolytic bacterium Caldicellulosiruptor bescii was applied to possibly enhance the methane production from steam-exploded birch in an anaerobic digestion (AD) process under thermophilic conditions (62 °C). Results: Overall, the combined SE and bioaugmentation enhanced the methane yield up to 140% compared to untreated birch, while SE alone contributed to the major share of methane enhancement by 118%. The best methane improvement of 140% on day 50 was observed in bottles fed with pretreated birch and bioaugmentation with lower dosages of C. bescii (2 and 5% of inoculum volume). The maximum methane production rate also increased from 4-mL CH4/ g VS (volatile solids)/day for untreated birch to 9-14-mL CH4/ g VS/day for steam-exploded birch with applied bioaugmentation. Bioaugmentation was particularly effective for increasing the initial methane production rate of the pretreated birch yielding 21-44% more methane than the pretreated birch without applied bioaugmentation. The extent of solubilization of the organic matter was increased by more than twofold when combined SE pretreatment and bioaugmentation was used in comparison with the methane production from untreated birch. The beneficial effects of SE and bioaugmentation on methane yield indicated that biomass recalcitrance and hydrolysis step are the limiting factors for efficient AD of lignocellulosic biomass. Microbial community analysis by 16S rRNA amplicon sequencing showed that the microbial community composition was altered by the pretreatment and bioaugmentation processes. Notably, the enhanced methane production by pretreatment and bioaugmentation was well correlated with the increase in abundance of key bacterial and archaeal communities, particularly the hydrolytic bacterium Caldicoprobacter, several members of syntrophic acetate oxidizing bacteria and the hydrogenotrophic Methanothermobacter. Conclusion: Our findings demonstrate the potential of combined SE and bioaugmentation for enhancing methane production from lignocellulosic biomass
Synthesis Paper: Targeted Livestock Grazing: Prescription for Healthy Rangelands
Targeted livestock grazing is a proven tool for manipulating rangeland vegetation, and current knowledge about targeted livestock grazing is extensive and expanding rapidly. Targeted grazing prescriptions optimize the timing, frequency, intensity, and selectivity of grazing (or browsing) in combinations that purposely exert grazing/browsing pressure on specific plant species or portions of the landscape. Targeted grazing differs from traditional grazing management in that the goal of targeted grazing is to apply defoliation or trampling to achieve specific vegetation management objectives, whereas the goal of traditional livestock grazing management is generally the production of livestock commodities. A shared aim of targeted livestock grazing and traditional grazing management is to sustain healthy soils, flora, fauna, and water resources that, in turn, can sustain natural ecological processes (e.g., nutrient cycle, water cycle, energy flow). Targeted grazing prescriptions integrate knowledge of plant ecology, livestock nutrition, and livestock foraging behavior. Livestock can be focused on target areas through fencing, herding, or supplement placement. Although practices can be developed to minimize the impact of toxins contained in target plants, the welfare of the animals used in targeted grazing must be a priority. Monitoring is needed to determine if targeted grazing is successful and to refine techniques to improve efficacy and efficiency. Examples of previous research studies and approaches are presented to highlight the ecological benefits that can be achieved when targeted grazing is applied properly. These cases include ways to suppress invasive plants and ways to enhance wildlife habitat and biodiversity. Future research should address the potential to select more adapted and effective livestock for targeted grazing and the associated animal welfare concerns with this practice. Targeted livestock grazing provides land managers a viable alternative to mechanical, chemical, and prescribed fire treatments to manipulate rangeland vegetation
High Throughput Deep Sequencing Reveals the Important Roles of MicroRNAs During Sweetpotato Storage at Chilling Temperature
Sweetpotato (Impomoea batatas L.) is a globally important economic food crop with a potential of becoming a bioenergy and pharmaceutical crop. Thus, studying the molecular mechanism of tuberous root development and storage is very important. However, not too much progress has been made
in this field. In this study, we employed the next generation high-throughput deep sequencing technology to sequence all small RNAs and degradome of sweetpotato for systematically investigating sweetpotato response to chilling stress during storage. A total of 190 known microRNAs (miRNAs)
and 191 novel miRNAs were identified, and 428 transcripts were targeted by 184 identified miRNAs. More importantly, we identified 26 miRNAs differentially expressed between chilling stress and control conditions. The expression of these miRNAs and their targets was also confirmed by qRT- PCR. Integrated analysis of small RNAs and degradome sequencing reveals that miRNA-mediated SA signaling, ABA-dependent, and ROS response pathways are involved in sweetpotato root response to chilling stress during storage
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Principles of Intensive Range Improvements
Our expanding population is demanding more productivity and other contributions from our rangelands. Range science is concerned with the plants, animals, soils, and waters on rangelands, particularly the interaction of these factors. Native plant communities should only be used as guides to determine site potential. Extensive practices on rangelands include manipulation of animals and burning. Intensive practices include control of unwanted plants, revegetation, and fertilization. When properly conducted, intensive manipulation practices often result in much higher production than before treatment. Each land manager determines the desired level of productivity based on economic, cultural, political, and social factors, and the availability of technology. The most effective method for control of unwanted plants varies with the sites, the species, and the degree of infestation. Revegetation may be required where desirable vegetation has been depleted by past grazing abuses, droughts, and encroachment of unwanted plants. Water is generally the primary factor limiting plant growth but when that need has been satisfied, additional plant nutrients such as nitrogen and phosphorus may be useful. The more costly practices are riskier and require higher management inputs, but the potential benefits are great. With changing technology or favorable economic conditions, the range manager may decide to intensify his range improvement efforts.This material was digitized as part of a cooperative project between the Society for Range Management and the University of Arizona Libraries.The Journal of Range Management archives are made available by the Society for Range Management and the University of Arizona Libraries. Contact [email protected] for further information.Migrated from OJS platform August 202
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Fertilizing Tobosa on Flood Plains in the Semidesert Grassland
This material was digitized as part of a cooperative project between the Society for Range Management and the University of Arizona Libraries.The Journal of Range Management archives are made available by the Society for Range Management and the University of Arizona Libraries. Contact [email protected] for further information.Migrated from OJS platform August 202
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Range Conservation and Season-long Grazing
This material was digitized as part of a cooperative project between the Society for Range Management and the University of Arizona Libraries.The Journal of Range Management archives are made available by the Society for Range Management and the University of Arizona Libraries. Contact [email protected] for further information.Migrated from OJS platform August 202
Unmittelbare Bürgerbeteiligung an Sachentscheidungen auf Landes- und Kommunalebene in Baden-Württemberg
Gerade in Zeiten zunehmender Politikverdrossenheit fordern immer mehr Bürger, die Instrumente direkter Demokratie zu vermehren und in den Voraussetzungen zu vereinfachen. Ob direkte Demokratie verfassungsrechtlich überhaupt zulässig ist, steht auf Bundesebene momentan zur Debatte. Auf Landes- und Kommunalebene ist diese Frage bereits zugunsten der unmittelbaren Bürgermitwirkung entschieden. Hier stellt sich aber die Frage, wie weitgehend die Bürger Einfluss nehmen können, also wie die Mitwirkungsmöglichkeiten rechtlich im Detail ausgestaltet sein können und sollen. Die Arbeit stellt einen Beitrag zu dieser aktuellen und gesellschaftspolitisch relevanten Problematik dar. Das Buch bietet - nach einem kurzen historischen Rückblick, der statistischen Aufarbeitung der Bedeutung direktdemokratischer Entscheidungen in Baden-Württemberg und der Klärung der (teilweise verwirrenden) Begrifflichkeiten - eine Darstellung des Bestands direktdemokratischer Mitwirkungsmöglichkeiten in Baden-Württemberg auf Landes- und Kommunalebene und geht auf die Problemstellungen ein, die sich in ihrem Zusammenhang ergeben. Es wird erläutert, über welche Themen in Baden-Württemberg ein zulässiges Bürgerbegehren oder Volksbegehren stattfinden kann und welche weiteren Anforderungen für die einzelnen Mitwirkungsmöglichkeiten bestehen. Dargestellt wird auch die wichtige Frage, wie in den verschiedenen Stadien direkter Bürgermitwirkung Rechtsschutz vor den Gerichten zu erlangen ist und wer an direktdemokratischen Abstimmungen teilnehmen darf. Es wird zudem für die einzelnen Zulässigkeitsvoraussetzungen geklärt, ob eine Vereinfachung zugunsten mehr direkter Demokratie rechtlich zulässig ist - und auch, ob sie rechtspolitisch Sinn macht. Das Buch ist daher nicht nur für die Wissenschaft, sondern auch für Bürger und Interessengruppen interessant, die sich über die Gegebenheiten und Möglichkeiten der direkten Demokratie in Baden- Württemberg informieren möchten
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The Effects of Limited Moisture on Germination an Initial Growth of Six Grass Species
This material was digitized as part of a cooperative project between the Society for Range Management and the University of Arizona Libraries.The Journal of Range Management archives are made available by the Society for Range Management and the University of Arizona Libraries. Contact [email protected] for further information.Migrated from OJS platform August 202
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