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Image-based modeling of carbon storage in fractured organic-rich shale with deep learning acceleration
No full textIn this study, we present three methods of predicting CO2 adsorption upon displacing CH4 in dehydrated fractured shale samples. These methods include a dynamic numerical approach, a steady state numerical approach, and a machine learning (ML){based approach. We develop a coupled formulation for including the effects of gas competitive adsorption, decompression, Knudsen diffusion, slippage, advection, and Fickiandiffusion for multicomponent single-phase CO2-CH4 systems. Several stochastic micro{structures of fractured shale samples are generated and processed for pore network extraction. Extracted pore networks contain microporosities as well as mesopores and fractures. Next, we show that the dynamic numerical approach can be substituted with steady state model which is only 2.3% less accurate but 3 to 4 orders of magnitudecomputationally faster to execute. In order to enhance the computational limits even further, we train a deep learning model on 3982 simulated steady state cases with r{squared greater than 0.93. In addition, we dene a storage quality criterion for recognizing suitable shale samples for CO2 sequestration which depends both on the rate and amount of adsorption. Using this criterion and the developed ML tool, a large number of shale pore{scale images can be ranked based on their suitability in an efficient and accurate manner. The proposed workflow is useful for selection of the proper geological locations for subsurface CO2 storage by analysing the available image datasets
Thermal ageing of a commercial LNT catalyst: effects on the structure and functionalities.
No full textHydrothermal degreening and ageing procedures were applied to a tri-metal (Pt-Pd-Rh) fully formulated lean NOX Trap catalyst to evaluate the effects of thermal stress on the performances and structural properties. X-ray absorption fine structure (XAFS) analysis revealed that the average size of the platinum particles was the same after degreening and ageing treatments. The formation of a new phase of alloyed Pt-Pd was observed to increase with the thermal load. The size of the ceria particles also increased after the ageing treatment. NOX storage capacity experiments revealed a substantial decrease of the concentration of active NOX storage sites which correlated with both ageing and degreening protocols. The performances of the treated catalyst were evaluated through spatially resolved (SpaciMS) lean-rich cycles. During the lean phase, the impact of the decrease in storage sites was significant on the aged sample, where an enlargement of the area required to achieve full storage was observed. On the other hand, the regeneration functionalities did not appear to be particularly affected by ageing. Rather, the aged sample showed a decrease of oxygen storage capacity (OSC), which promoted a lower reductant consumption and therefore a quicker and more efficient reduction process. On the other hand, the different distributions of adsorbed species by the end of the lean phase produced greater spread presence of NH3 and NOX slip along the channels of the aged sample during the reduction
Can autocracy promote literacy? evidence from a cultural alignment success story
No full textDo countries with less democratic forms of government necessarily have lower literacy rates as a consequence? Using a random sample of more than 9000 individuals from military archives in 20th century Portugal, we show that 20-year old males were 50% more likely to end up literate under a nondemocratic regime than under a more democratic one. Our results are robust to controlling for a host of factors including economic growth, the disease environment, and regional fixed-effects. We argue for a political economy and cultural explanation for the relative success of the authoritarian regime in promoting basic education
Long-term Treatment with Telotristat Ethyl in Patients with Carcinoid Syndrome Symptoms: Results from the TELEPATH Study
No full textIntroductionTelotristat ethyl is indicated for use in combination with somatostatin analogs (SSAs) to treat carcinoid syndrome (CS) diarrhea uncontrolled by SSAs alone in adults, but long-term safety and efficacy data beyond 48 weeks are needed.ObjectiveEvaluate the long-term safety and tolerability of telotristat ethyl and its effect on quality of life (QOL) in patients with CS.MethodsIn this phase 3, nonrandomized, multicenter, open-label, long-term extension study (TELEPATH), patients who participated in phase 2 or 3 trials of telotristat ethyl continued treatment at their present dose level (250 or 500 mg thrice daily) for 84 weeks. Safety and tolerability, the primary endpoint, were assessed by monitoring adverse events (AEs), serious adverse events (SAEs), adverse events of special interest (AESIs, including liver-related AEs, depression, and gastrointestinal AEs), and deaths. The secondary objective was to evaluate changes in patients’ QOL using validated cancer questionnaires and a subjective global assessment of CS symptoms.ResultsIn 124 patients exposed to telotristat ethyl for a mean of 102.6 ± 53.2 weeks, the type and frequency of AEs were consistent with those reported in previous trials. The occurrence of AESIs was not related to dosage or duration of therapy. Most AEs were mild to moderate in severity, and no deaths were related to telotristat ethyl. QOL scores remained stable and the majority of patients reported adequate symptom relief throughout the study.ConclusionsSafety results of TELEPATH support the long-term use of telotristat ethyl in patients with CS diarrhea. Telotristat ethyl was well tolerated and associated with sustained improvement in QOL scores (NCT02026063). <br/
Non-Representational Theory. By Paul Simpson. Oxon: Routledge. 2021. Xi + 254 pp. £32.99 Paperback. ISBN: 978-1-13855219-7.
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Lock-down, Slow-down:Impact of COVID-19 Lockdown on Physical Activity using data from Cardiac Devices
No full textIn response to the COVID-19 pandemic, the UK was placed under strict lockdown measures on March 23rd 2020. The aim of this study was to quantify the effects on physical activity levels utilising data from the prospective Triage-HF Plus study. This represents a cohort of adult patients with implanted cardiac devices capable of measuring activity by embedded accelerometery via a remote monitoring platform. Activity data were available for the 4 weeks pre- and post- implementation of ‘stay at home’ lockdown measures in the form of ‘minutes active per day’ (mins/day). Data were analysed for 311 patients (77.2% male, mean age 68.8, frailty 55.9%. 92.2% established heart failure diagnosis, of these 51.2% NYHA II), with co—morbidities representative of a real-world cohort.Post- lockdown, a significant reduction in median physical activity equating to 20.8 active mins/day was seen. The reduction was uniform with a slightly more pronounced drop in PA for females, but no statistically significant difference with respect to age, BMI, frailty or device type. Activity dropped in the immediate 2-week period post lockdown, but steadily returned thereafter. Median activity week 4 weeks post lockdown remained significantly lower than 4 weeks pre-lockdown (p = <0.001).In a population of predominantly heart failure patients with cardiac devices, activity reduced by approximately 20 minutes active per day in the immediate aftermath of strict COVID-19 lockdown measures
Modelling hollow thermoplastic syntactic foams under high-strain compressive loading
No full textThe mechanical response of syntactic foams comprising hollow thermoplastic microspheres (HTMs) embedded in a polyurethane matrix were experimentally examined under uniaxial compressive strain. Phenomenological strain energy models were subsequently developed to capture both the axial stress-strain and transverse strain response of the foams. HTM syntactic foams were found to exhibit increased small-strain stiffness with reduced density, revealing a highlytuneable and extremely lightweight syntactic foam blend for applications. The foams were also found to become strongly compressible at large strains and possess a high threshold for plastic deformation, making them a robust alternative to hollow glass microsphere syntactic foams. The non-standard transverse strain relationship exhibited by HTM syntactic foams at high filling fractions was captured by Ogden-type strain energy models. The thermal characteristics of these syntactic foams were also explored with Differential Scanning Calorimetry testing which showed that HTMs have a negligible impact on the thermal characteristics of the matrix
The predictive ability of the 313-variant-based polygenic risk score for contralateral breast cancer risk prediction in women of European ancestry with a heterozygote BRCA1 or BRCA2 pathogenic variant
No full textPurpose To evaluate the association between a previously published 313-variant-based breast cancer (BC) polygenic risk score (PRS313) and contralateral breast cancer (CBC) risk, in BRCA1 and BRCA2 pathogenic variant heterozygotes. Methods We included women of European ancestry with a prevalent first primary invasive BC (BRCA1=6,591 with 1,402 prevalent CBC cases; BRCA2=4,208 with 647 prevalent CBC cases) from CIMBA, a large international retrospective series. Cox regression analysis was performed to assess the association between overall and ER-specific PRS313 and CBC risk. Results For BRCA1 heterozygotes the estrogen receptor (ER)-negative PRS313 showed the largest association with CBC risk, HR per SD=1.12, 95%CI [1.06-1.18], C-index=0.53; for BRCA2 heterozygotes, this was the ER-positive PRS313, HR=1.15, 95%CI [1.07-1.25], C-index=0.57. Adjusting for family history, age at diagnosis, treatment or pathological characteristics for the first BC did not change association effect sizes. For women developing first BC <age 40 years, the cumulative PRS313 5th and 95th percentile 10-year CBC risks were 22% and 32% for BRCA1 and 13% and 23% for BRCA2 heterozygotes, respectively. Conclusion The PRS313 can be used to refine individual CBC risks for BRCA1/2 heterozygotes of European ancestry, however the PRS313 needs to be considered in the context of a multifactorial risk model to evaluate whether it might influence clinical-decision-making
