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description Publicationkeyboard_double_arrow_right Article 2018 United KingdomAmerican Geophysical Union (AGU) ARC | Tracking the response of ..., ARC | Discovery Indigenous - Gr..., NSERCARC| Tracking the response of the Australian climate to abrupt climate change ,ARC| Discovery Indigenous - Grant ID: IN140100050 ,NSERCKristen K. Beck; Michael-Shawn Fletcher; Patricia Gadd; Henk Heijnis; Krystyna M. Saunders; Gavin Simpson; Atun Zawadzki;doi: 10.1002/2017jg004135
AbstractCritical transitions in ecosystem states are often sudden and unpredictable. Consequently, there is a concerted effort to identify measurable early warning signals (EWS) for these important events. Aquatic ecosystems provide an opportunity to observe critical transitions due to their high sensitivity and rapid response times. Using palaeoecological techniques, we can measure properties of time series data to determine if critical transitions are preceded by any measurable ecosystem metrics, that is, identify EWS. Using a suite of palaeoenvironmental data spanning the last 2,400 years (diatoms, pollen, geochemistry, and charcoal influx), we assess whether a critical transition in diatom community structure was preceded by measurable EWS. Lake Vera, in the temperate rain forest of western Tasmania, Australia, has a diatom community dominated by Discostella stelligera and undergoes an abrupt compositional shift at ca. 820 cal yr BP that is concomitant with increased fire disturbance of the local vegetation. This shift is manifest as a transition from less oligotrophic acidic diatom flora (Achnanthidium minutissimum, Brachysira styriaca, and Fragilaria capucina) to more oligotrophic acidic taxa (Frustulia elongatissima, Eunotia diodon, and Gomphonema multiforme). We observe a marked increase in compositional variance and rate‐of‐change prior to this critical transition, revealing these metrics are useful EWS in this system. Interestingly, vegetation remains complacent to fire disturbance until after the shift in the diatom community. Disturbance taxa invade and the vegetation system experiences an increase in both compositional variance and rate‐of‐change. These trends imply an approaching critical transition in the vegetation and the probable collapse of the local rain forest system.
Journal of Geophysic... arrow_drop_down Journal of Geophysical Research BiogeosciencesArticle . 2018License: Wiley Online Library User AgreementData sources: Crossrefadd ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
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For further information contact us at helpdesk@openaire.eu23 citations 23 popularity Top 10% influence Average impulse Top 10% Powered by BIP!visibility 6visibility views 6 download downloads 91 Powered bymore_vert Journal of Geophysic... arrow_drop_down Journal of Geophysical Research BiogeosciencesArticle . 2018License: Wiley Online Library User AgreementData sources: Crossrefadd ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
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For further information contact us at helpdesk@openaire.eudescription Publicationkeyboard_double_arrow_right Preprint , Article 2020Elsevier BV NSERCNSERCAuthors: Ning Sun; Chen Yang; Ričardas Zitikis;Ning Sun; Chen Yang; Ričardas Zitikis;AbstractWe develop an anomaly detection method when systematic anomalies, possibly statistically very similar to genuine inputs, are affecting control systems at the input and/or output stages. The method allows anomaly free inputs (i.e., those before contamination) to originate from a wide class of random sequences, thus opening up possibilities for diverse applications. To illustrate how the method works on data, and how to interpret its results and make decisions, we analyze several actual time series, which are originally nonstationary but in the process of analysis are converted into stationary. As a further illustration, we provide a controlled experiment with anomaly free inputs following an ARMA time series model under various contamination scenarios.
arXiv.org e-Print Ar... arrow_drop_down SSRN Electronic Journal; Applied Stochastic Models in Business and IndustryArticleData sources: UnpayWallApplied Stochastic Models in Business and IndustryArticle . 2022License: Wiley Online Library User AgreementData sources: Crossrefadd ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
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For further information contact us at helpdesk@openaire.eu3 citations 3 popularity Top 10% influence Average impulse Average Powered by BIP!more_vert arXiv.org e-Print Ar... arrow_drop_down SSRN Electronic Journal; Applied Stochastic Models in Business and IndustryArticleData sources: UnpayWallApplied Stochastic Models in Business and IndustryArticle . 2022License: Wiley Online Library User AgreementData sources: Crossrefadd ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
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For further information contact us at helpdesk@openaire.eudescription Publicationkeyboard_double_arrow_right Article 2020Elsevier BV NSERCNSERCJose L. Torero; Jason I. Gerhard; Márcio Ferreira Martins; Marco A.B. Zanoni; Tarek L. Rashwan; Joshua K. Brown;Abstract Smouldering combustion is an important and complex phenomenon that is central to a wide range of problems (hazards) and solutions (applications). A rich history of research in the context of fire safety has yet to be integrated with the more recent, rapidly growing body of work in engineered smouldering solutions. The variety of disciplines, materials involved, and perspectives on smouldering have resulted in a lack of unity in the expression of key concepts, terminology used, interpretation of results, and conclusions extracted. This review brings together theoretical, experimental, and modelling studies across both fire safety and applied smouldering research to produce a unified conceptual understanding of smouldering combustion. The review includes (i) an overview of the fundamental processes with a synthesis of nomenclature to generate a consistent set of terms for these fundamental processes, (ii) a distillation of ignition, extinction, and transition to flaming research, (iii) a review of the temporal and spatial distribution of heat and mass transfer processes as well as their solution using analytical and numerical methods, (iv) an overview of smouldering emissions and emission treatment systems, and (v) a summary of key gaps and opportunities for future research. Beyond merely review, a new conceptual model is provided that articulates similarities and critical differences between the two main smouldering systems: porous solid fuels and condensed fuels in inert porous media. A quantitative analysis of this conceptual model reveals that the evolution of a smouldering front, while a local process, is determined by a global energy balance that is cumulative in time and has to be integrated in space. As such, the fate of a smouldering reaction can be predicted before the effects of global heat exchange have impacted the reaction. This approach is relevant to all forms of smouldering (including fire safety), but it is particularly important when using smouldering as an engineered process that results in the positive use of the energy released by the smouldering reaction (applied smouldering). In applied smouldering, predicting the fate of a reaction ahead of time allows operators to modify the conditions of the process to maintain self-sustained smouldering propagation and thus fully harness the benefits of the reaction.
Progress in Energy a... arrow_drop_down Progress in Energy and Combustion ScienceArticle . 2020License: Elsevier TDMData sources: Crossrefadd ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
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For further information contact us at helpdesk@openaire.eu81 citations 81 popularity Top 1% influence Top 10% impulse Top 1% Powered by BIP!more_vert Progress in Energy a... arrow_drop_down Progress in Energy and Combustion ScienceArticle . 2020License: Elsevier TDMData sources: Crossrefadd ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://www.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.1016/j.pecs.2020.100869&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.eudescription Publicationkeyboard_double_arrow_right Article 2016 United KingdomWiley NSERCNSERCBunting, L.; Leavitt, P. R.; Simpson, G. L.; Wissel, B.; Laird, K. R.; Cumming, B. F.; St. Amand, A.; Engstrom, D. R.;doi: 10.1002/lno.10355
Eutrophication can initiate sudden ecosystem state change either by slowly pushing lakes toward a catastrophic tipping point beyond which self-reinforcing mechanisms establish an alternate stable state, or through rapid but persistent changes in external forcing mechanisms. In principle, these processes can be distinguished by determining whether historical changes in focal parameters (phytoplankton) exhibit transient (rising then declining) or continuously-elevated variability characteristic of alternate stable states or a “paradox of enrichment,” respectively. We tested this hypothesis in the south basin of Lake Winnipeg, Canada, a site with intense blooms of N2-fixing cyanobacteria since 1990, but for which little is known of earlier limnological conditions, causes of eutrophication, or whether modern conditions represent a alternate stable state. Paleolimnological analysis revealed that the basin was naturally mesotrophic (∼15–20 μg P L−1) with diazotrophic cyanobacteria, productive diatoms, and phosphorus-rich sediments. Eutrophication accelerated during ca.1900–ca.1990, when sedimentary nitrogen, phosphorus and carbon contents increased 10–50%, δ15N enriched 3–4‰, and concentrations of many fossil pigments increased 300–500%. Nearly 75% of 20th century variability was explained by concomitant increases in production of livestock and crops, but not by climate. After ca.1990, the basin exhibited a rapid threefold increase in akinetes from Aphanizomenon and Anabaena spp. and 50% declines in pigments from chlorophytes and cyanobacteria because of sudden socio-economic reorganization of agriculture. Phytoplankton variability quantified using Gaussian generalized additive models increased continuously since the onset of agriculture for bloom-forming taxa, did not decline after state change, and suggested that recovery should not be affected by stable-state hysteresis.
add ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://www.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.1002/lno.10355&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.eu86 citations 86 popularity Top 1% influence Top 10% impulse Top 10% Powered by BIP!more_vert add ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://www.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.1002/lno.10355&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.eudescription Publicationkeyboard_double_arrow_right Article , Other literature type , Preprint 2019 Germany, Italy, Switzerland, GermanyCopernicus GmbH UKRI | Understanding and Attribu..., UKRI | Sources and Impacts of Sh...UKRI| Understanding and Attributing Composition-Climate Feedbacks in the Earth System ,UKRI| Sources and Impacts of Short-Lived Anthropogenic ChlorineA. Chrysanthou; A. C. Maycock; M. P. Chipperfield; S. Dhomse; H. Garny; H. Garny; D. Kinnison; H. Akiyoshi; M. Deushi; R. R. Garcia; P. Jöckel; O. Kirner; G. Pitari; D. A. Plummer; L. Revell; E. Rozanov; E. Rozanov; A. Stenke; T. Y. Tanaka; D. Visioni; Y. Yamashita; Y. Yamashita;We perform the first multi-model intercomparison of the impact of nudged meteorology on the stratospheric residual circulation using hindcast simulations from the Chemistry–Climate Model Initiative (CCMI). We examine simulations over the period 1980–2009 from seven models in which the meteorological fields are nudged towards a reanalysis dataset and compare these with their equivalent free-running simulations and the reanalyses themselves. We show that for the current implementations, nudging meteorology does not constrain the mean strength of the stratospheric residual circulation and that the inter-model spread is similar, or even larger, than in the free-running simulations. The nudged models generally show slightly stronger upwelling in the tropical lower stratosphere compared to the free-running versions and exhibit marked differences compared to the directly estimated residual circulation from the reanalysis dataset they are nudged towards. Downward control calculations applied to the nudged simulations reveal substantial differences between the climatological lower-stratospheric tropical upward mass flux (TUMF) computed from the modelled wave forcing and that calculated directly from the residual circulation. This explicitly shows that nudging decouples the wave forcing and the residual circulation so that the divergence of the angular momentum flux due to the mean motion is not balanced by eddy motions, as would typically be expected in the time mean. Overall, nudging meteorological fields leads to increased inter-model spread for most of the measures of the mean climatological stratospheric residual circulation assessed in this study. In contrast, the nudged simulations show a high degree of consistency in the inter-annual variability in the TUMF in the lower stratosphere, which is primarily related to the contribution to variability from the resolved wave forcing. The more consistent inter-annual variability in TUMF in the nudged models also compares more closely with the variability found in the reanalyses, particularly in boreal winter. We apply a multiple linear regression (MLR) model to separate the drivers of inter-annual and long-term variations in the simulated TUMF; this explains up to ∼75 % of the variance in TUMF in the nudged simulations. The MLR model reveals a statistically significant positive trend in TUMF for most models over the period 1980–2009. The TUMF trend magnitude is generally larger in the nudged models compared to their free-running counterparts, but the intermodel range of trends doubles from around a factor of 2 to a factor of 4 due to nudging. Furthermore, the nudged models generally do not match the TUMF trends in the reanalysis they are nudged towards for trends over different periods in the interval 1980–2009. Hence, we conclude that nudging does not strongly constrain long-term trends simulated by the chemistry–climate model (CCM) in the residual circulation. Our findings show that while nudged simulations may, by construction, produce accurate temperatures and realistic representations of fast horizontal transport, this is not typically the case for the slower zonal mean vertical transport in the stratosphere. Consequently, caution is required when using nudged simulations to interpret the behaviour of stratospheric tracers that are affected by the residual circulation. Atmospheric Chemistry and Physics, 19 (17) ISSN:1680-7375 ISSN:1680-7367
CORE (RIOXX-UK Aggre... arrow_drop_down Atmospheric Chemistry and Physics (ACP)Other literature type . 2019Data sources: Copernicus PublicationsAtmospheric Chemistry and Physics (ACP)Other literature type . 2019Data sources: Copernicus Publicationsadd ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://www.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.5194/acp-2019-260&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.eu25 citations 25 popularity Top 10% influence Average impulse Top 10% Powered by BIP!visibility 6visibility views 6 download downloads 7 Powered bymore_vert CORE (RIOXX-UK Aggre... arrow_drop_down Atmospheric Chemistry and Physics (ACP)Other literature type . 2019Data sources: Copernicus PublicationsAtmospheric Chemistry and Physics (ACP)Other literature type . 2019Data sources: Copernicus Publicationsadd ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://www.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.5194/acp-2019-260&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.eudescription Publicationkeyboard_double_arrow_right Preprint , Article , Other literature type 2018 FranceCopernicus GmbH EC | STRATOCLIM, SNSF | Study to determine Spectr..., SNSF | Volcanic Eruptions and th... +1 projectsEC| STRATOCLIM ,SNSF| Study to determine Spectral Solar Irradiance and its impact on the middle atmosphere (SIMA) ,SNSF| Volcanic Eruptions and their impact on future Climate (VEC) ,SNSF| Future and Past Solar Influence on the Terrestrial Climate IIKévin Lamy; Thierry Portafaix; Béatrice Josse; Colette Brogniez; Sophie Godin-Beekmann; Hassan Bencherif; Laura E. Revell; Hideharu Akiyoshi; Slimane Bekki; Michaela I. Hegglin; Patrick Jöckel; Oliver Kirner; Virginie Marécal; Olaf Morgenstern; Andrea Stenke; Guang Zeng; N. Luke Abraham; Alexander T. Archibald; N. Butchart; Martyn P. Chipperfield; Glauco Di Genova; Makoto Deushi; Sandip Dhomse; Rong-Ming Hu; Douglas E. Kinnison; Martine Michou; Fiona M. O'Connor; Luke D. Oman; Giovanni Pitari; David A. Plummer; John A. Pyle; Eugene Rozanov; David Saint-Martin; Kengo Sudo; Taichu Tanaka; Daniele Visioni; Kohei Yoshida;We have derived values of the Ultraviolet Index (UVI) at solar noon using the Tropospheric Ultraviolet Model (TUV) driven by ozone, temperature and aerosol fields from climate simulations of the first phase of the Chemistry-Climate Model Initiative (CCMI-1). Since clouds remain one of the largest uncertainties in climate projections, we simulated only the clear-sky UVI. We compared the modelled UVI climatologies against present-day climatological values of UVI derived from both satellite data (the OMI-Aura OMUVBd product) and ground-based measurements (from the NDACC network). Depending on the region, relative differences between the UVI obtained from CCMI/TUV calculations and the ground-based measurements ranged between −5.9% and 10.6%. We then calculated the UVI evolution throughout the 21st century for the four Representative Concentration Pathways (RCPs 2.6, 4.5, 6.0 and 8.5). Compared to 1960s values, we found an average increase in the UVI in 2100 (of 2–4%) in the tropical belt (30°N-30°S). For the mid-latitudes, we observed a 1.8 to 3.4 % increase in the Southern Hemisphere for RCP 2.6, 4.5 and 6.0, and found a 2.3% decrease in RCP 8.5. Higher increases in UVI are projected in the Northern Hemisphere except for RCP 8.5. At high latitudes, ozone recovery is well identified and induces a complete return of mean UVI levels to 1960 values for RCP 8.5 in the Southern Hemisphere. In the Northern Hemisphere, UVI levels in 2100 are higher by 0.5 to 5.5% for RCP 2.6, 4.5 and 6.0 and they are lower by 7.9% for RCP 8.5. We analysed the impacts of greenhouse gases (GHGs) and ozone-depleting substances (ODSs) on UVI from 1960 by comparing CCMI sensitivity simulations (1960–2100) with fixed GHGs or ODSs at their respective 1960 levels. As expected with ODS fixed at their 1960 levels, there is no large decrease in ozone levels and consequently no sudden increase in UVI levels. With fixed GHG, we observed a delayed return of ozone to 1960 values, with a corresponding pattern of change observed on UVI, and looking at the UVI difference between 2090s values and 1960s values, we found an 8 % increase in the tropical belt during the summer of each hemisphere. Finally we show that, while in the Southern Hemisphere the UVI is mainly driven by total ozone column, in the Northern Hemisphere both total ozone column and aerosol optical depth drive UVI levels, with aerosol optical depth having twice as much influence on the UVI as total ozone column does.
add ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://www.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.5194/acp-2018-525&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.eu10 citations 10 popularity Top 10% influence Average impulse Top 10% Powered by BIP!more_vert add ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://www.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.5194/acp-2018-525&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.eudescription Publicationkeyboard_double_arrow_right Article , Preprint 2020Oxford University Press (OUP) NSF | MRI: Development of a Hig..., ARC | ARC Centres of Excellence..., NSF | Enabling a New Instrument... +2 projectsNSF| MRI: Development of a High Resolution Infrared Spectrograph with a Large Spectral Grasp ,ARC| ARC Centres of Excellence - Grant ID: CE170100013 ,NSF| Enabling a New Instrument 'IGRINS' for the Gemini South Telescope User Community ,UKRI| Hertfordshire Astronomy 2018-2021 ,UKRI| BRIdging Disciplines of Galactic Chemical Evolution (BRIDGCE): The Rise of the Chemical ElementsAldo Mura-Guzmán; David Yong; C. Abate; Amanda I. Karakas; Chiaki Kobayashi; Heeyoung Oh; S. H. Chun; Gregory N. Mace;We present new fluorine abundance estimations in two carbon enhanced metal-poor (CEMP) stars, HE 1429-0551 and HE 1305+0007. HE 1429-0551 is also enriched in slow neutron-capture process (s-process) elements, a CEMP-s, and HE 1305+0007 is enhanced in both, slow and rapid neutron-capture process elements, a CEMP-s/r. The F abundances estimates are derived from the vibration-rotation transition of the HF molecule at 23358.6 A using high-resolution infrared spectra obtained with the Immersion Grating Infrared Spectrometer (IGRINS) at the 4m-class Lowell Discovery Telescope. Our results include a F abundance measurement in HE 1429-0551 of A(F) = +3.93 ([F/Fe] = +1.90) at [Fe/H] = -2.53, and a F upper limit in HE 1305+0007 of A(F) < +3.28 ([F/Fe] < +1.00) at [Fe/H] = -2.28. Our new derived F abundance in HE 1429-0551 makes this object the most metal-poor star where F has been detected. We carefully compare these results with literature values and state-of-the-art CEMP-s model predictions including detailed AGB nucleosynthesis and binary evolution. The modelled fluorine abundance for HE 1429-0551 is within reasonable agreement with our observed abundance, although is slightly higher than our observed value. For HE 1429-0551, our findings support the scenario via mass transfer by a primary companion during its thermally-pulsing phase. Our estimated upper limit in HE 1305+0007, along with data from the literature, shows large discrepancies compared with AGB models. The discrepancy is principally due to the simultaneous s- and r-process element enhancements which the model struggles to reproduce. 12 pages, 5 Figures -- Accepted in MNRAS
Monthly Notices of t... arrow_drop_down Monthly Notices of the Royal Astronomical SocietyArticle . 2020License: OUP Standard Publication ReuseData sources: Crossrefhttps://doi.org/10.48550/arxiv...Article . 2020License: arXiv Non-Exclusive DistributionData sources: Dataciteadd ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://www.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.1093/mnras/staa2610&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.eu2 citations 2 popularity Average influence Average impulse Average Powered by BIP!more_vert Monthly Notices of t... arrow_drop_down Monthly Notices of the Royal Astronomical SocietyArticle . 2020License: OUP Standard Publication ReuseData sources: Crossrefhttps://doi.org/10.48550/arxiv...Article . 2020License: arXiv Non-Exclusive DistributionData sources: Dataciteadd ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://www.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.1093/mnras/staa2610&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.eudescription Publicationkeyboard_double_arrow_right Article 2015Authors: Steve Paterson; James LaCourse; Philippe J Dufresne;Steve Paterson; James LaCourse; Philippe J Dufresne;The liver fluke Fasciola hepatica is a major pathogen of livestock worldwide, causing huge economic losses to agriculture, as well as 2.4 million human infections annually. Here we provide a draft genome for F. hepatica, which we find to be among the largest known pathogen genomes at 1.3 Gb. This size cannot be explained by genome duplication or expansion of a single repeat element, and remains a paradox given the burden it may impose on egg production necessary to transmit infection. Despite the potential for inbreeding by facultative self-fertilisation, substantial levels of polymorphism were found, which highlights the evolutionary potential for rapid adaptation to changes in host availability, climate change or to drug or vaccine interventions. Non-synonymous polymorphisms were elevated in genes shared with parasitic taxa, which may be particularly relevant for the ability of the parasite to adapt to a broad range of definitive mammalian and intermediate molluscan hosts. Large-scale transcriptional changes, particularly within expanded protease and tubulin families, were found as the parasite migrated from the gut, across the peritoneum and through the liver to mature in the bile ducts. We identify novel members of anti-oxidant and detoxification pathways and defined their differential expression through infection, which may explain the stage-specific efficacy of different anthelmintic drugs. The genome analysis described here provides new insights into the evolution of this important pathogen, its adaptation to the host environment and external selection pressures. This analysis also provides a platform for research into novel drugs and vaccines.
Genome Biology; Open... arrow_drop_down add ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
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For further information contact us at helpdesk@openaire.eu213 citations 213 popularity Top 1% influence Top 10% impulse Top 1% Powered by BIP!more_vert Genome Biology; Open... arrow_drop_down add ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
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For further information contact us at helpdesk@openaire.eudescription Publicationkeyboard_double_arrow_right Article 2016American Chemical Society (ACS) ARC | Development of the next g...ARC| Development of the next generation of organo-mineral fertilisers utilising domestic and commercial waste productsAditya Rawal; Stephen Joseph; James M. Hook; C. H. Chia; Paul Munroe; Scott W. Donne; Yun Lin; David Phelan; David R. G. Mitchell; Ben Pace; Joseph Horvat; J. Beau W. Webber;pmid: 27284608
Dramatic changes in molecular structure, degradation pathway, and porosity of biochar are observed at pyrolysis temperatures ranging from 250 to 550 °C when bamboo biomass is pretreated by iron-sulfate-clay slurries (iron-clay biochar), as compared to untreated bamboo biochar. Electron microscopy analysis of the biochar reveals the infusion of mineral species into the pores of the biochar and the formation of mineral nanostructures. Quantitative (13)C nuclear magnetic resonance (NMR) spectroscopy shows that the presence of the iron clay prevents degradation of the cellulosic fraction at pyrolysis temperatures of 250 °C, whereas at higher temperatures (350-550 °C), the clay promotes biomass degradation, resulting in an increase in both the concentrations of condensed aromatic, acidic, and phenolic carbon species. The porosity of the biochar, as measured by NMR cryoporosimetry, is altered by the iron-clay pretreatment. In the presence of the clay, at lower pyrolysis temperatures, the biochar develops a higher pore volume, while at higher temperature, the presence of clay causes a reduction in the biochar pore volume. The most dramatic reduction in pore volume is observed in the kaolinite-infiltrated biochar at 550 °C, which is attributed to the blocking of the mesopores (2-50 nm pore) by the nonporous metakaolinite formed from kaolinite.
add ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
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For further information contact us at helpdesk@openaire.eu146 citations 146 popularity Top 1% influence Top 10% impulse Top 1% Powered by BIP!more_vert add ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
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For further information contact us at helpdesk@openaire.eudescription Publicationkeyboard_double_arrow_right Article , Preprint 2017 Denmark, Italy, France, Italy, France, Argentina, ArgentinaAmerican Astronomical Society NSF | Nearby Supernovae: Discov..., NSF | Measuring the Universe wi..., EC | SPCND +2 projectsNSF| Nearby Supernovae: Discovery at Birth and Follow-up Studies ,NSF| Measuring the Universe with Supernovae ,EC| SPCND ,NSF| The Carnegie Supernova Project: Extending the Near-IR Hubble diagram for SNe Ia to z < 0.08 ,NSF| The Carnegie Supernova Program - IIClaudia P. Gutiérrez; Joseph P. Anderson; Mario Hamuy; Nidia Morrell; Santiago González-Gaitán; Maximilian Stritzinger; Mark M. Phillips; Lluís Galbany; Gastón Folatelli; Luc Dessart; Carlos Contreras; Massimo Della Valle; Wendy L. Freedman; Eric Hsiao; Kevin Krisciunas; Barry F. Madore; Jose Maza; Nicholas B. Suntzeff; Jose L. Prieto; Luis González; Enrico Cappellaro; M. Navarrete; Alessandro Pizzella; Maria Teresa Ruiz; R. Chris Smith; Massimo Turatto;handle: 11336/41312 , 11577/3252767
We present 888 visual-wavelength spectra of 122 nearby type II supernovae (SNe II) obtained between 1986 and 2009, and ranging between 3 and 363 days post explosion. In this first paper, we outline our observations and data reduction techniques, together with a characterization based on the spectral diversity of SNe~II. A statistical analysis of the spectral matching technique is discussed as an alternative to non-detection constraints for estimating SN explosion epochs. The time evolution of spectral lines is presented and analysed in terms of how this differs for SNe of different photometric, spectral, and environmental properties: velocities, pseudo-equivalent widths, decline rates, magnitudes, time durations, and environment metallicity. Our sample displays a large range in ejecta expansion velocities, from $\sim9600$ to $\sim1500$ km s$^{-1}$ at 50 days post explosion with a median H$_{\alpha}$ value of 7300 km s$^{-1}$. This is most likely explained through differing explosion energies. Significant diversity is also observed in the absolute strength of spectral lines, characterised through their pseudo-equivalent widths. This implies significant diversity in both temperature evolution (linked to progenitor radius) and progenitor metallicity between different SNe~II. Around 60\% of our sample show an extra absorption component on the blue side of the H$_{\alpha}$ P-Cygni profile ("Cachito" feature) between 7 and 120 days since explosion. Studying the nature of Cachito, we conclude that these features at early times (before $\sim35$ days) are associated with \ion{Si}{2} $\lambda6355$, while past the middle of the plateau phase they are related to high velocity (HV) features of hydrogen lines. Comment: Accepted for publication in ApJ. 112 pages, 153 figures, 9 tables
CONICET Digital (CON... arrow_drop_down OA@INAF - Istituto Nazionale di AstrofisicaArticle . 2017Data sources: OA@INAF - Istituto Nazionale di Astrofisicahttps://doi.org/10.48550/arxiv...Article . 2017License: arXiv Non-Exclusive DistributionData sources: Dataciteadd ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
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For further information contact us at helpdesk@openaire.eu84 citations 84 popularity Top 1% influence Top 10% impulse Top 1% Powered by BIP!visibility 11visibility views 11 download downloads 79 Powered bymore_vert CONICET Digital (CON... arrow_drop_down OA@INAF - Istituto Nazionale di AstrofisicaArticle . 2017Data sources: OA@INAF - Istituto Nazionale di Astrofisicahttps://doi.org/10.48550/arxiv...Article . 2017License: arXiv Non-Exclusive DistributionData sources: Dataciteadd ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
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description Publicationkeyboard_double_arrow_right Article 2018 United KingdomAmerican Geophysical Union (AGU) ARC | Tracking the response of ..., ARC | Discovery Indigenous - Gr..., NSERCARC| Tracking the response of the Australian climate to abrupt climate change ,ARC| Discovery Indigenous - Grant ID: IN140100050 ,NSERCKristen K. Beck; Michael-Shawn Fletcher; Patricia Gadd; Henk Heijnis; Krystyna M. Saunders; Gavin Simpson; Atun Zawadzki;doi: 10.1002/2017jg004135
AbstractCritical transitions in ecosystem states are often sudden and unpredictable. Consequently, there is a concerted effort to identify measurable early warning signals (EWS) for these important events. Aquatic ecosystems provide an opportunity to observe critical transitions due to their high sensitivity and rapid response times. Using palaeoecological techniques, we can measure properties of time series data to determine if critical transitions are preceded by any measurable ecosystem metrics, that is, identify EWS. Using a suite of palaeoenvironmental data spanning the last 2,400 years (diatoms, pollen, geochemistry, and charcoal influx), we assess whether a critical transition in diatom community structure was preceded by measurable EWS. Lake Vera, in the temperate rain forest of western Tasmania, Australia, has a diatom community dominated by Discostella stelligera and undergoes an abrupt compositional shift at ca. 820 cal yr BP that is concomitant with increased fire disturbance of the local vegetation. This shift is manifest as a transition from less oligotrophic acidic diatom flora (Achnanthidium minutissimum, Brachysira styriaca, and Fragilaria capucina) to more oligotrophic acidic taxa (Frustulia elongatissima, Eunotia diodon, and Gomphonema multiforme). We observe a marked increase in compositional variance and rate‐of‐change prior to this critical transition, revealing these metrics are useful EWS in this system. Interestingly, vegetation remains complacent to fire disturbance until after the shift in the diatom community. Disturbance taxa invade and the vegetation system experiences an increase in both compositional variance and rate‐of‐change. These trends imply an approaching critical transition in the vegetation and the probable collapse of the local rain forest system.
Journal of Geophysic... arrow_drop_down Journal of Geophysical Research BiogeosciencesArticle . 2018License: Wiley Online Library User AgreementData sources: Crossrefadd ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
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For further information contact us at helpdesk@openaire.eu23 citations 23 popularity Top 10% influence Average impulse Top 10% Powered by BIP!visibility 6visibility views 6 download downloads 91 Powered bymore_vert Journal of Geophysic... arrow_drop_down Journal of Geophysical Research BiogeosciencesArticle . 2018License: Wiley Online Library User AgreementData sources: Crossrefadd ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
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For further information contact us at helpdesk@openaire.eudescription Publicationkeyboard_double_arrow_right Preprint , Article 2020Elsevier BV NSERCNSERCAuthors: Ning Sun; Chen Yang; Ričardas Zitikis;Ning Sun; Chen Yang; Ričardas Zitikis;AbstractWe develop an anomaly detection method when systematic anomalies, possibly statistically very similar to genuine inputs, are affecting control systems at the input and/or output stages. The method allows anomaly free inputs (i.e., those before contamination) to originate from a wide class of random sequences, thus opening up possibilities for diverse applications. To illustrate how the method works on data, and how to interpret its results and make decisions, we analyze several actual time series, which are originally nonstationary but in the process of analysis are converted into stationary. As a further illustration, we provide a controlled experiment with anomaly free inputs following an ARMA time series model under various contamination scenarios.
arXiv.org e-Print Ar... arrow_drop_down SSRN Electronic Journal; Applied Stochastic Models in Business and IndustryArticleData sources: UnpayWallApplied Stochastic Models in Business and IndustryArticle . 2022License: Wiley Online Library User AgreementData sources: Crossrefadd ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
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For further information contact us at helpdesk@openaire.eu3 citations 3 popularity Top 10% influence Average impulse Average Powered by BIP!more_vert arXiv.org e-Print Ar... arrow_drop_down SSRN Electronic Journal; Applied Stochastic Models in Business and IndustryArticleData sources: UnpayWallApplied Stochastic Models in Business and IndustryArticle . 2022License: Wiley Online Library User AgreementData sources: Crossrefadd ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
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For further information contact us at helpdesk@openaire.eudescription Publicationkeyboard_double_arrow_right Article 2020Elsevier BV NSERCNSERCJose L. Torero; Jason I. Gerhard; Márcio Ferreira Martins; Marco A.B. Zanoni; Tarek L. Rashwan; Joshua K. Brown;Abstract Smouldering combustion is an important and complex phenomenon that is central to a wide range of problems (hazards) and solutions (applications). A rich history of research in the context of fire safety has yet to be integrated with the more recent, rapidly growing body of work in engineered smouldering solutions. The variety of disciplines, materials involved, and perspectives on smouldering have resulted in a lack of unity in the expression of key concepts, terminology used, interpretation of results, and conclusions extracted. This review brings together theoretical, experimental, and modelling studies across both fire safety and applied smouldering research to produce a unified conceptual understanding of smouldering combustion. The review includes (i) an overview of the fundamental processes with a synthesis of nomenclature to generate a consistent set of terms for these fundamental processes, (ii) a distillation of ignition, extinction, and transition to flaming research, (iii) a review of the temporal and spatial distribution of heat and mass transfer processes as well as their solution using analytical and numerical methods, (iv) an overview of smouldering emissions and emission treatment systems, and (v) a summary of key gaps and opportunities for future research. Beyond merely review, a new conceptual model is provided that articulates similarities and critical differences between the two main smouldering systems: porous solid fuels and condensed fuels in inert porous media. A quantitative analysis of this conceptual model reveals that the evolution of a smouldering front, while a local process, is determined by a global energy balance that is cumulative in time and has to be integrated in space. As such, the fate of a smouldering reaction can be predicted before the effects of global heat exchange have impacted the reaction. This approach is relevant to all forms of smouldering (including fire safety), but it is particularly important when using smouldering as an engineered process that results in the positive use of the energy released by the smouldering reaction (applied smouldering). In applied smouldering, predicting the fate of a reaction ahead of time allows operators to modify the conditions of the process to maintain self-sustained smouldering propagation and thus fully harness the benefits of the reaction.
Progress in Energy a... arrow_drop_down Progress in Energy and Combustion ScienceArticle . 2020License: Elsevier TDMData sources: Crossrefadd ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
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For further information contact us at helpdesk@openaire.eu81 citations 81 popularity Top 1% influence Top 10% impulse Top 1% Powered by BIP!more_vert Progress in Energy a... arrow_drop_down Progress in Energy and Combustion ScienceArticle . 2020License: Elsevier TDMData sources: Crossrefadd ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
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For further information contact us at helpdesk@openaire.eudescription Publicationkeyboard_double_arrow_right Article 2016 United KingdomWiley NSERCNSERCBunting, L.; Leavitt, P. R.; Simpson, G. L.; Wissel, B.; Laird, K. R.; Cumming, B. F.; St. Amand, A.; Engstrom, D. R.;doi: 10.1002/lno.10355
Eutrophication can initiate sudden ecosystem state change either by slowly pushing lakes toward a catastrophic tipping point beyond which self-reinforcing mechanisms establish an alternate stable state, or through rapid but persistent changes in external forcing mechanisms. In principle, these processes can be distinguished by determining whether historical changes in focal parameters (phytoplankton) exhibit transient (rising then declining) or continuously-elevated variability characteristic of alternate stable states or a “paradox of enrichment,” respectively. We tested this hypothesis in the south basin of Lake Winnipeg, Canada, a site with intense blooms of N2-fixing cyanobacteria since 1990, but for which little is known of earlier limnological conditions, causes of eutrophication, or whether modern conditions represent a alternate stable state. Paleolimnological analysis revealed that the basin was naturally mesotrophic (∼15–20 μg P L−1) with diazotrophic cyanobacteria, productive diatoms, and phosphorus-rich sediments. Eutrophication accelerated during ca.1900–ca.1990, when sedimentary nitrogen, phosphorus and carbon contents increased 10–50%, δ15N enriched 3–4‰, and concentrations of many fossil pigments increased 300–500%. Nearly 75% of 20th century variability was explained by concomitant increases in production of livestock and crops, but not by climate. After ca.1990, the basin exhibited a rapid threefold increase in akinetes from Aphanizomenon and Anabaena spp. and 50% declines in pigments from chlorophytes and cyanobacteria because of sudden socio-economic reorganization of agriculture. Phytoplankton variability quantified using Gaussian generalized additive models increased continuously since the onset of agriculture for bloom-forming taxa, did not decline after state change, and suggested that recovery should not be affected by stable-state hysteresis.
add ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://www.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.1002/lno.10355&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.eu86 citations 86 popularity Top 1% influence Top 10% impulse Top 10% Powered by BIP!more_vert add ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://www.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.1002/lno.10355&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.eudescription Publicationkeyboard_double_arrow_right Article , Other literature type , Preprint 2019 Germany, Italy, Switzerland, GermanyCopernicus GmbH UKRI | Understanding and Attribu..., UKRI | Sources and Impacts of Sh...UKRI| Understanding and Attributing Composition-Climate Feedbacks in the Earth System ,UKRI| Sources and Impacts of Short-Lived Anthropogenic ChlorineA. Chrysanthou; A. C. Maycock; M. P. Chipperfield; S. Dhomse; H. Garny; H. Garny; D. Kinnison; H. Akiyoshi; M. Deushi; R. R. Garcia; P. Jöckel; O. Kirner; G. Pitari; D. A. Plummer; L. Revell; E. Rozanov; E. Rozanov; A. Stenke; T. Y. Tanaka; D. Visioni; Y. Yamashita; Y. Yamashita;We perform the first multi-model intercomparison of the impact of nudged meteorology on the stratospheric residual circulation using hindcast simulations from the Chemistry–Climate Model Initiative (CCMI). We examine simulations over the period 1980–2009 from seven models in which the meteorological fields are nudged towards a reanalysis dataset and compare these with their equivalent free-running simulations and the reanalyses themselves. We show that for the current implementations, nudging meteorology does not constrain the mean strength of the stratospheric residual circulation and that the inter-model spread is similar, or even larger, than in the free-running simulations. The nudged models generally show slightly stronger upwelling in the tropical lower stratosphere compared to the free-running versions and exhibit marked differences compared to the directly estimated residual circulation from the reanalysis dataset they are nudged towards. Downward control calculations applied to the nudged simulations reveal substantial differences between the climatological lower-stratospheric tropical upward mass flux (TUMF) computed from the modelled wave forcing and that calculated directly from the residual circulation. This explicitly shows that nudging decouples the wave forcing and the residual circulation so that the divergence of the angular momentum flux due to the mean motion is not balanced by eddy motions, as would typically be expected in the time mean. Overall, nudging meteorological fields leads to increased inter-model spread for most of the measures of the mean climatological stratospheric residual circulation assessed in this study. In contrast, the nudged simulations show a high degree of consistency in the inter-annual variability in the TUMF in the lower stratosphere, which is primarily related to the contribution to variability from the resolved wave forcing. The more consistent inter-annual variability in TUMF in the nudged models also compares more closely with the variability found in the reanalyses, particularly in boreal winter. We apply a multiple linear regression (MLR) model to separate the drivers of inter-annual and long-term variations in the simulated TUMF; this explains up to ∼75 % of the variance in TUMF in the nudged simulations. The MLR model reveals a statistically significant positive trend in TUMF for most models over the period 1980–2009. The TUMF trend magnitude is generally larger in the nudged models compared to their free-running counterparts, but the intermodel range of trends doubles from around a factor of 2 to a factor of 4 due to nudging. Furthermore, the nudged models generally do not match the TUMF trends in the reanalysis they are nudged towards for trends over different periods in the interval 1980–2009. Hence, we conclude that nudging does not strongly constrain long-term trends simulated by the chemistry–climate model (CCM) in the residual circulation. Our findings show that while nudged simulations may, by construction, produce accurate temperatures and realistic representations of fast horizontal transport, this is not typically the case for the slower zonal mean vertical transport in the stratosphere. Consequently, caution is required when using nudged simulations to interpret the behaviour of stratospheric tracers that are affected by the residual circulation. Atmospheric Chemistry and Physics, 19 (17) ISSN:1680-7375 ISSN:1680-7367
CORE (RIOXX-UK Aggre... arrow_drop_down Atmospheric Chemistry and Physics (ACP)Other literature type . 2019Data sources: Copernicus PublicationsAtmospheric Chemistry and Physics (ACP)Other literature type . 2019Data sources: Copernicus Publicationsadd ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
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For further information contact us at helpdesk@openaire.eu25 citations 25 popularity Top 10% influence Average impulse Top 10% Powered by BIP!visibility 6visibility views 6 download downloads 7 Powered bymore_vert CORE (RIOXX-UK Aggre... arrow_drop_down Atmospheric Chemistry and Physics (ACP)Other literature type . 2019Data sources: Copernicus PublicationsAtmospheric Chemistry and Physics (ACP)Other literature type . 2019Data sources: Copernicus Publicationsadd ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://www.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.5194/acp-2019-260&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.eudescription Publicationkeyboard_double_arrow_right Preprint , Article , Other literature type 2018 FranceCopernicus GmbH EC | STRATOCLIM, SNSF | Study to determine Spectr..., SNSF | Volcanic Eruptions and th... +1 projectsEC| STRATOCLIM ,SNSF| Study to determine Spectral Solar Irradiance and its impact on the middle atmosphere (SIMA) ,SNSF| Volcanic Eruptions and their impact on future Climate (VEC) ,SNSF| Future and Past Solar Influence on the Terrestrial Climate IIKévin Lamy; Thierry Portafaix; Béatrice Josse; Colette Brogniez; Sophie Godin-Beekmann; Hassan Bencherif; Laura E. Revell; Hideharu Akiyoshi; Slimane Bekki; Michaela I. Hegglin; Patrick Jöckel; Oliver Kirner; Virginie Marécal; Olaf Morgenstern; Andrea Stenke; Guang Zeng; N. Luke Abraham; Alexander T. Archibald; N. Butchart; Martyn P. Chipperfield; Glauco Di Genova; Makoto Deushi; Sandip Dhomse; Rong-Ming Hu; Douglas E. Kinnison; Martine Michou; Fiona M. O'Connor; Luke D. Oman; Giovanni Pitari; David A. Plummer; John A. Pyle; Eugene Rozanov; David Saint-Martin; Kengo Sudo; Taichu Tanaka; Daniele Visioni; Kohei Yoshida;We have derived values of the Ultraviolet Index (UVI) at solar noon using the Tropospheric Ultraviolet Model (TUV) driven by ozone, temperature and aerosol fields from climate simulations of the first phase of the Chemistry-Climate Model Initiative (CCMI-1). Since clouds remain one of the largest uncertainties in climate projections, we simulated only the clear-sky UVI. We compared the modelled UVI climatologies against present-day climatological values of UVI derived from both satellite data (the OMI-Aura OMUVBd product) and ground-based measurements (from the NDACC network). Depending on the region, relative differences between the UVI obtained from CCMI/TUV calculations and the ground-based measurements ranged between −5.9% and 10.6%. We then calculated the UVI evolution throughout the 21st century for the four Representative Concentration Pathways (RCPs 2.6, 4.5, 6.0 and 8.5). Compared to 1960s values, we found an average increase in the UVI in 2100 (of 2–4%) in the tropical belt (30°N-30°S). For the mid-latitudes, we observed a 1.8 to 3.4 % increase in the Southern Hemisphere for RCP 2.6, 4.5 and 6.0, and found a 2.3% decrease in RCP 8.5. Higher increases in UVI are projected in the Northern Hemisphere except for RCP 8.5. At high latitudes, ozone recovery is well identified and induces a complete return of mean UVI levels to 1960 values for RCP 8.5 in the Southern Hemisphere. In the Northern Hemisphere, UVI levels in 2100 are higher by 0.5 to 5.5% for RCP 2.6, 4.5 and 6.0 and they are lower by 7.9% for RCP 8.5. We analysed the impacts of greenhouse gases (GHGs) and ozone-depleting substances (ODSs) on UVI from 1960 by comparing CCMI sensitivity simulations (1960–2100) with fixed GHGs or ODSs at their respective 1960 levels. As expected with ODS fixed at their 1960 levels, there is no large decrease in ozone levels and consequently no sudden increase in UVI levels. With fixed GHG, we observed a delayed return of ozone to 1960 values, with a corresponding pattern of change observed on UVI, and looking at the UVI difference between 2090s values and 1960s values, we found an 8 % increase in the tropical belt during the summer of each hemisphere. Finally we show that, while in the Southern Hemisphere the UVI is mainly driven by total ozone column, in the Northern Hemisphere both total ozone column and aerosol optical depth drive UVI levels, with aerosol optical depth having twice as much influence on the UVI as total ozone column does.
add ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://www.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.5194/acp-2018-525&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.eu10 citations 10 popularity Top 10% influence Average impulse Top 10% Powered by BIP!more_vert add ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://www.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.5194/acp-2018-525&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.eudescription Publicationkeyboard_double_arrow_right Article , Preprint 2020Oxford University Press (OUP) NSF | MRI: Development of a Hig..., ARC | ARC Centres of Excellence..., NSF | Enabling a New Instrument... +2 projectsNSF| MRI: Development of a High Resolution Infrared Spectrograph with a Large Spectral Grasp ,ARC| ARC Centres of Excellence - Grant ID: CE170100013 ,NSF| Enabling a New Instrument 'IGRINS' for the Gemini South Telescope User Community ,UKRI| Hertfordshire Astronomy 2018-2021 ,UKRI| BRIdging Disciplines of Galactic Chemical Evolution (BRIDGCE): The Rise of the Chemical ElementsAldo Mura-Guzmán; David Yong; C. Abate; Amanda I. Karakas; Chiaki Kobayashi; Heeyoung Oh; S. H. Chun; Gregory N. Mace;We present new fluorine abundance estimations in two carbon enhanced metal-poor (CEMP) stars, HE 1429-0551 and HE 1305+0007. HE 1429-0551 is also enriched in slow neutron-capture process (s-process) elements, a CEMP-s, and HE 1305+0007 is enhanced in both, slow and rapid neutron-capture process elements, a CEMP-s/r. The F abundances estimates are derived from the vibration-rotation transition of the HF molecule at 23358.6 A using high-resolution infrared spectra obtained with the Immersion Grating Infrared Spectrometer (IGRINS) at the 4m-class Lowell Discovery Telescope. Our results include a F abundance measurement in HE 1429-0551 of A(F) = +3.93 ([F/Fe] = +1.90) at [Fe/H] = -2.53, and a F upper limit in HE 1305+0007 of A(F) < +3.28 ([F/Fe] < +1.00) at [Fe/H] = -2.28. Our new derived F abundance in HE 1429-0551 makes this object the most metal-poor star where F has been detected. We carefully compare these results with literature values and state-of-the-art CEMP-s model predictions including detailed AGB nucleosynthesis and binary evolution. The modelled fluorine abundance for HE 1429-0551 is within reasonable agreement with our observed abundance, although is slightly higher than our observed value. For HE 1429-0551, our findings support the scenario via mass transfer by a primary companion during its thermally-pulsing phase. Our estimated upper limit in HE 1305+0007, along with data from the literature, shows large discrepancies compared with AGB models. The discrepancy is principally due to the simultaneous s- and r-process element enhancements which the model struggles to reproduce. 12 pages, 5 Figures -- Accepted in MNRAS
Monthly Notices of t... arrow_drop_down Monthly Notices of the Royal Astronomical SocietyArticle . 2020License: OUP Standard Publication ReuseData sources: Crossrefhttps://doi.org/10.48550/arxiv...Article . 2020License: arXiv Non-Exclusive DistributionData sources: Dataciteadd ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://www.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.1093/mnras/staa2610&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.eu2 citations 2 popularity Average influence Average impulse Average Powered by BIP!more_vert Monthly Notices of t... arrow_drop_down Monthly Notices of the Royal Astronomical SocietyArticle . 2020License: OUP Standard Publication ReuseData sources: Crossrefhttps://doi.org/10.48550/arxiv...Article . 2020License: arXiv Non-Exclusive DistributionData sources: Dataciteadd ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://www.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.1093/mnras/staa2610&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.eudescription Publicationkeyboard_double_arrow_right Article 2015Authors: Steve Paterson; James LaCourse; Philippe J Dufresne;Steve Paterson; James LaCourse; Philippe J Dufresne;The liver fluke Fasciola hepatica is a major pathogen of livestock worldwide, causing huge economic losses to agriculture, as well as 2.4 million human infections annually. Here we provide a draft genome for F. hepatica, which we find to be among the largest known pathogen genomes at 1.3 Gb. This size cannot be explained by genome duplication or expansion of a single repeat element, and remains a paradox given the burden it may impose on egg production necessary to transmit infection. Despite the potential for inbreeding by facultative self-fertilisation, substantial levels of polymorphism were found, which highlights the evolutionary potential for rapid adaptation to changes in host availability, climate change or to drug or vaccine interventions. Non-synonymous polymorphisms were elevated in genes shared with parasitic taxa, which may be particularly relevant for the ability of the parasite to adapt to a broad range of definitive mammalian and intermediate molluscan hosts. Large-scale transcriptional changes, particularly within expanded protease and tubulin families, were found as the parasite migrated from the gut, across the peritoneum and through the liver to mature in the bile ducts. We identify novel members of anti-oxidant and detoxification pathways and defined their differential expression through infection, which may explain the stage-specific efficacy of different anthelmintic drugs. The genome analysis described here provides new insights into the evolution of this important pathogen, its adaptation to the host environment and external selection pressures. This analysis also provides a platform for research into novel drugs and vaccines.
Genome Biology; Open... arrow_drop_down add ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://www.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.1186/s13059-015-0632-2&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.eu213 citations 213 popularity Top 1% influence Top 10% impulse Top 1% Powered by BIP!more_vert Genome Biology; Open... arrow_drop_down add ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://www.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.1186/s13059-015-0632-2&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.eudescription Publicationkeyboard_double_arrow_right Article 2016American Chemical Society (ACS) ARC | Development of the next g...ARC| Development of the next generation of organo-mineral fertilisers utilising domestic and commercial waste productsAditya Rawal; Stephen Joseph; James M. Hook; C. H. Chia; Paul Munroe; Scott W. Donne; Yun Lin; David Phelan; David R. G. Mitchell; Ben Pace; Joseph Horvat; J. Beau W. Webber;pmid: 27284608
Dramatic changes in molecular structure, degradation pathway, and porosity of biochar are observed at pyrolysis temperatures ranging from 250 to 550 °C when bamboo biomass is pretreated by iron-sulfate-clay slurries (iron-clay biochar), as compared to untreated bamboo biochar. Electron microscopy analysis of the biochar reveals the infusion of mineral species into the pores of the biochar and the formation of mineral nanostructures. Quantitative (13)C nuclear magnetic resonance (NMR) spectroscopy shows that the presence of the iron clay prevents degradation of the cellulosic fraction at pyrolysis temperatures of 250 °C, whereas at higher temperatures (350-550 °C), the clay promotes biomass degradation, resulting in an increase in both the concentrations of condensed aromatic, acidic, and phenolic carbon species. The porosity of the biochar, as measured by NMR cryoporosimetry, is altered by the iron-clay pretreatment. In the presence of the clay, at lower pyrolysis temperatures, the biochar develops a higher pore volume, while at higher temperature, the presence of clay causes a reduction in the biochar pore volume. The most dramatic reduction in pore volume is observed in the kaolinite-infiltrated biochar at 550 °C, which is attributed to the blocking of the mesopores (2-50 nm pore) by the nonporous metakaolinite formed from kaolinite.
add ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://www.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.1021/acs.est.6b00685&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.eu146 citations 146 popularity Top 1% influence Top 10% impulse Top 1% Powered by BIP!more_vert add ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://www.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.1021/acs.est.6b00685&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.eudescription Publicationkeyboard_double_arrow_right Article , Preprint 2017 Denmark, Italy, France, Italy, France, Argentina, ArgentinaAmerican Astronomical Society NSF | Nearby Supernovae: Discov..., NSF | Measuring the Universe wi..., EC | SPCND +2 projectsNSF| Nearby Supernovae: Discovery at Birth and Follow-up Studies ,NSF| Measuring the Universe with Supernovae ,EC| SPCND ,NSF| The Carnegie Supernova Project: Extending the Near-IR Hubble diagram for SNe Ia to z < 0.08 ,NSF| The Carnegie Supernova Program - IIClaudia P. Gutiérrez; Joseph P. Anderson; Mario Hamuy; Nidia Morrell; Santiago González-Gaitán; Maximilian Stritzinger; Mark M. Phillips; Lluís Galbany; Gastón Folatelli; Luc Dessart; Carlos Contreras; Massimo Della Valle; Wendy L. Freedman; Eric Hsiao; Kevin Krisciunas; Barry F. Madore; Jose Maza; Nicholas B. Suntzeff; Jose L. Prieto; Luis González; Enrico Cappellaro; M. Navarrete; Alessandro Pizzella; Maria Teresa Ruiz; R. Chris Smith; Massimo Turatto;handle: 11336/41312 , 11577/3252767
We present 888 visual-wavelength spectra of 122 nearby type II supernovae (SNe II) obtained between 1986 and 2009, and ranging between 3 and 363 days post explosion. In this first paper, we outline our observations and data reduction techniques, together with a characterization based on the spectral diversity of SNe~II. A statistical analysis of the spectral matching technique is discussed as an alternative to non-detection constraints for estimating SN explosion epochs. The time evolution of spectral lines is presented and analysed in terms of how this differs for SNe of different photometric, spectral, and environmental properties: velocities, pseudo-equivalent widths, decline rates, magnitudes, time durations, and environment metallicity. Our sample displays a large range in ejecta expansion velocities, from $\sim9600$ to $\sim1500$ km s$^{-1}$ at 50 days post explosion with a median H$_{\alpha}$ value of 7300 km s$^{-1}$. This is most likely explained through differing explosion energies. Significant diversity is also observed in the absolute strength of spectral lines, characterised through their pseudo-equivalent widths. This implies significant diversity in both temperature evolution (linked to progenitor radius) and progenitor metallicity between different SNe~II. Around 60\% of our sample show an extra absorption component on the blue side of the H$_{\alpha}$ P-Cygni profile ("Cachito" feature) between 7 and 120 days since explosion. Studying the nature of Cachito, we conclude that these features at early times (before $\sim35$ days) are associated with \ion{Si}{2} $\lambda6355$, while past the middle of the plateau phase they are related to high velocity (HV) features of hydrogen lines. Comment: Accepted for publication in ApJ. 112 pages, 153 figures, 9 tables
CONICET Digital (CON... arrow_drop_down OA@INAF - Istituto Nazionale di AstrofisicaArticle . 2017Data sources: OA@INAF - Istituto Nazionale di Astrofisicahttps://doi.org/10.48550/arxiv...Article . 2017License: arXiv Non-Exclusive DistributionData sources: Dataciteadd ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://www.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.3847/1538-4357/aa8f52&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.eu84 citations 84 popularity Top 1% influence Top 10% impulse Top 1% Powered by BIP!visibility 11visibility views 11 download downloads 79 Powered bymore_vert CONICET Digital (CON... arrow_drop_down OA@INAF - Istituto Nazionale di AstrofisicaArticle . 2017Data sources: OA@INAF - Istituto Nazionale di Astrofisicahttps://doi.org/10.48550/arxiv...Article . 2017License: arXiv Non-Exclusive DistributionData sources: Dataciteadd ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://www.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.3847/1538-4357/aa8f52&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.eu