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Idealized Carbon-Based Materials Exhibiting Record Deliverable Capacities for Vehicular Methane Storage
Materials
for vehicular methane storage have been extensively studied,
although no suitable material has been found. In this work, we use
molecular simulation to investigate three types of carbon-based materials,
Schwarzites, layered graphenes, and carbon nanoscrolls, for use in
vehicular methane storage under adsorption conditions of 65 bar and
298 K and desorption conditions of 5.8 bar and 358 K. Ten different
Schwarzites were tested and found to have high adsorption with maximums
at 273 VSTP/V, but middling deliverable capacities of no
more than 131 VSTP/V. Layered graphene and graphene nanoscrolls
were found to have extremely high CH4 adsorption capacities
of 355 and 339 VSTP/V, respectively, when the interlayer
distance was optimized to 11 Å. The deliverable capacities of
perfectly layered graphene and graphene nanoscrolls were also found
to be exceptional with values of 266 and 252 VSTP/V, respectively,
with optimized interlayer distances. These values make idealized graphene
and nanoscrolls the record holders for adsorption and deliverable
capacities under vehicular methane storage conditions
Backbone and side chain 1H, 15N and 13C assignments for a thiol-disulphide oxidoreductase from the Antarctic bacterium Pseudoalteromonas haloplanktis TAC125
Enzymes produced by psychrophilic organisms have successfully overcome the low temperature challenge and evolved to maintain high catalytic rates in their permanently cold environments. As an initial step in our attempt to elucidate the cold-adaptation strategies used by these enzymes we report here the 1H, 15N and 13C assignments for the reduced form of a thiol-disulphide oxidoreductase from the Antarctic bacterium Pseudoalteromonas haloplanktis TAC125.The NMR spectrometers are part of The National NMR Network (REDE/1517/RMN/2005), supported by ‘‘Programa Operacional Ciência e Inovação (POCTI) 2010’’ and Fundação para a Ciência e a Tecnologia (FCT). This work was funded by FCT, POCTI and FEDER; Projects POCI/BIA-PRO/57263/2004 and PTDC/BIO/70806/2006. TC is holder of a long term EMBO fellowship. MM is thankful to the Fundação para a Ciência e Tecnologia for its support through Programa Ciência 2007.info:eu-repo/semantics/publishedVersio
Tidal dynamics and mangrove carbon sequestration during the Oligo–Miocene in the South China Sea
Modern mangroves are among the most carbon-rich biomes on Earth, but their long-term (≥106 yr) impact on the global carbon cycle is unknown. The extent, productivity and preservation of mangroves are controlled by the interplay of tectonics, global sea level and sedimentation, including tide, wave and fluvial processes. The impact of these processes on mangrove-bearing successions in the Oligo–Miocene of the South China Sea (SCS) is evaluated herein. Palaeogeographic reconstructions, palaeotidal modelling, and facies analysis suggest that elevated tidal range and bed shear stress optimised mangrove development along tide-influenced tropical coastlines. Preservation of mangrove organic carbon (OC) was promoted by high tectonic subsidence and fluvial sediment supply. Lithospheric storage of OC in peripheral SCS basins potentially exceeded 4000 Gt (equivalent to 2000 ppm of atmospheric CO2). These results highlight the crucial impact of tectonic and oceanographic processes on mangrove OC sequestration within the global carbon cycle on geological timescales
Computability of ordinary differential equations
In this paper we provide a brief review of several results about the
computability of initial-value problems (IVPs) defined with ordinary differential
equations (ODEs). We will consider a variety of settings and analyze
how the computability of the IVP will be affected. Computational
complexity results will also be presented, as well as computable versions
of some classical theorems about the asymptotic behavior of ODEs.info:eu-repo/semantics/publishedVersio
A systematic review of the effectiveness of docetaxel and mitoxantrone for the treatment of metastatic hormone-refractory prostate cancer
A systematic review was performed to evaluate the clinical effectiveness of docetaxel in combination with prednisolone (docetaxel is licensed in the UK for use in combination with prednisone or prednisolone for the treatment of patients with metastatic hormone-refractory prostate cancer. Prednisone is not used in the UK, but it is reasonable to use docetaxel plus prednisone data in this review of docetaxel plus prednisolone) for the treatment of metastatic hormone-refractory prostate cancer. A scoping search identified a trial of docetaxel plus prednisone vs mitoxantrone plus prednisone, but did not identify any trials comparing docetaxel plus prednisolone/prednisone with any other treatments. Therefore, we considered additional indirect evidence that would enable a comparison of docetaxel plus prednisolone/prednisone with other chemotherapy regimens and active supportive care. Systematic searching (upto April 2005) identified seven randomised controlled trials. One large well-conducted trial assessed docetaxel plus prednisone vs mitoxantrone plus prednisone; this showed statistically significant improvements with 3-weekly docetaxel in terms of overall survival, quality of life, pain response and PSA decline. Two other chemotherapy regimens that included docetaxel with estramustine also showed improved outcomes in comparison with mitoxantrone plus prednisone. Three trials that compared mitoxantrone plus corticosteroids with corticosteroids alone were identified and their results for overall survival combined, which showed very little difference between the two groups. The addition of clodronate to mitoxantrone plus prednisone showed no significant differences in comparison with mitoxantrone plus prednisone alone. The evidence suggests that chemotherapy regimens containing 3-weekly docetaxel are superior to mitoxantrone or corticosteroids alone
Behavioural and Physiological Correlates of the Canine Frustration Questionnaire
Frustration is a negative emotional state implicated in a range of canine behaviour problems. The Canine Frustration Questionnaire (CFQ) is the first psychometric tool developed to assess frustration tendencies in dogs based on owner report. However, to date, no published studies have assessed behavioural and physiological correlates of this trait. A novel behaviour test battery was developed to induce frustration in dogs, mapping onto the CFQ. Forty-four dogs were recruited and filmed whilst undertaking the test battery, and a CFQ was completed by each owner. Targeted behavioural measures were assessed from this footage, based on hypotheses aimed at evaluating convergent and discriminant validity with facets of the CFQ. In addition, a saliva sample was collected pre- and post-testing for 39 dogs, and a cortisol assay performed using ELISA to provide a physiological measure of arousal. A range of predicted behavioural test measures (e.g., vocalising and lunging) positively correlated with CFQ scores. For 22 dogs with pre-test salivary cortisol levels of <4 ng/mL (indicative of normal arousal at baseline), cortisol change and post-test cortisol levels positively correlated with the CFQ PC5 ‘Frustration coping’ score. These results provide further evidence of the validity of frustration tendencies as measured by owner report through the CFQ
The Canine Frustration Questionnaire—Development of a New Psychometric Tool for Measuring Frustration in Domestic Dogs (Canis familiaris)
Introduction: Psychometric tools have been developed for the assessment of behavioral and affective traits in non-human animals. Frustration can be defined as an emotional reaction experienced after a given expectation is violated. Frustration is a negative emotional state and whilst it probably plays a key role in certain behavior problems in dogs (e.g., aggressive behaviors), there appears to have been little attempt to scale this affective tendency. Therefore, the aim of the current study was to develop a tool to assess frustration tendencies in dogs.
Materials and Methods: An online owner survey was developed. Items covered demographics, the training/behavioral history of the dog, and 33 frustration related items scored using a 5-point Likert scale. The questionnaire was disseminated via on-line channels over a 5-month period. Two thousand three hundred forty-eight respondents completed the questionnaire. Of these, 273 respondents completed it a second time 6 weeks later, and a separate 276 respondents completed it a second time 1 year later. Additionally, 92 paired responses were collected where two carers completed the questionnaire independently about the same dog. Intra- and inter-rater reliabilities were assessed prior to structuring the items using principal component analysis (PCA) with a Varimax rotation. Items were retained if they loaded > 0.4 on at least one of the components extracted using the Kaiser criterion.
Results: Twenty-two items were deemed to be reliable enough to be used in the PCA and 21 items loaded on a biologically meaningful 5-principal component solution. There was a significant positive correlation between each principal component and the owners' general perception of their dogs' frustration tendencies, alongside other expected correlates.
Conclusion: This is the first reliable psychometric tool for the assessment of frustration in dogs—the Canine Frustration Questionnaire (CFQ). Further validation with behavioral tests and physiological measures is ongoing
Deposition and preservation of fluvio-tidal shallow-marine sandstones: A re-evaluation of the Neoproterozoic Jura Quartzite (western Scotland)
The 2 to 5 km thick, sandstone‐dominated (>90%) Jura Quartzite is an extreme example of a mature Neoproterozoic sandstone, previously interpreted as a tide‐influenced shelf deposit and herein re‐interpreted within a fluvio‐tidal deltaic depositional model. Three issues are addressed: (i) evidence for the re‐interpretation from tidal shelf to tidal delta; (ii) reasons for vertical facies uniformity; and (iii) sand supply mechanisms to form thick tidal‐shelf sandstones. The predominant facies (compound cross‐bedded, coarse‐grained sandstones) represents the lower parts of metres to tens of metres high, transverse fluvio‐tidal bedforms with superimposed smaller bedforms. Ubiquitous erosional surfaces, some with granule–pebble lags, record erosion of the upper parts of those bedforms. There was selective preservation of the higher energy, topographically‐lower, parts of channel‐bar systems. Strongly asymmetrical, bimodal, palaeocurrents are interpreted as due to associated selective preservation of fluvially‐enhanced ebb tidal currents. Finer‐grained facies are scarce, due largely to suspended sediment bypass. They record deposition in lower‐energy environments, including channel mouth bars, between and down depositional‐dip of higher energy fluvio‐ebb tidal bars. The lack of wave‐formed sedimentary structures and low continuity of mudstone and sandstone interbeds, support deposition in a non‐shelf setting. Hence, a sand‐rich, fluvial–tidal, current‐dominated, largely sub‐tidal, delta setting is proposed. This new interpretation avoids the problem of transporting large amounts of coarse sand to a shelf. Facies uniformity and vertical stacking are likely due to sediment oversupply and bypass rather than balanced sediment supply and subsidence rates. However, facies evidence of relative sea level changes is difficult to recognise, which is attributed to: (i) the areally extensive and polygenetic nature of the preserved facies, and (ii) a large stored sediment buffer that dampened response to relative sea‐level and/or sediment supply changes. Consideration of preservation bias towards high‐energy deposits may be more generally relevant, especially to thick Neoproterozoic and Lower Palaeozoic marine sandstones
ReadNet: A Hierarchical Transformer Framework for Web Article Readability Analysis
Analyzing the readability of articles has been an important sociolinguistic
task. Addressing this task is necessary to the automatic recommendation of
appropriate articles to readers with different comprehension abilities, and it
further benefits education systems, web information systems, and digital
libraries. Current methods for assessing readability employ empirical measures
or statistical learning techniques that are limited by their ability to
characterize complex patterns such as article structures and semantic meanings
of sentences. In this paper, we propose a new and comprehensive framework which
uses a hierarchical self-attention model to analyze document readability. In
this model, measurements of sentence-level difficulty are captured along with
the semantic meanings of each sentence. Additionally, the sentence-level
features are incorporated to characterize the overall readability of an article
with consideration of article structures. We evaluate our proposed approach on
three widely-used benchmark datasets against several strong baseline
approaches. Experimental results show that our proposed method achieves the
state-of-the-art performance on estimating the readability for various web
articles and literature.Comment: ECIR 202
Computability and dynamical systems
In this paper we explore results that establish a link between dynamical
systems and computability theory (not numerical analysis). In the last few decades,
computers have increasingly been used as simulation tools for gaining insight into
dynamical behavior. However, due to the presence of errors inherent in such numerical
simulations, with few exceptions, computers have not been used for the
nobler task of proving mathematical results. Nevertheless, there have been some recent
developments in the latter direction. Here we introduce some of the ideas and
techniques used so far, and suggest some lines of research for further work on this
fascinating topic
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