The prevalence and clinical features of epileptic seizures in a memory clinic population

This is the author accepted manuscript. The final version is available from Elsevier via the DOI in this record.Purpose: To determine the prevalence and clinical features of epileptic seizures occurring in a memory clinic population. Method: We recruited patients receiving a diagnosis of dementia or mild cognitive impairment (MCI) at a regional memory clinic. We interviewed patients and informants using a proforma designed to elicit symptoms suggestive of epilepsy. Informants also completed the Clinical Dementia Rating Scale (CDR) and the Cambridge Behavioural Inventory- Revised (CBI-R). Patients underwent cognitive testing using the Addenbrooke's Cognitive Examination – III (ACE-III). We also recruited an age- and gender- matched control group with no history of cognitive impairment. Diagnoses of dementia/MCI were checked against current diagnostic criteria. Results: We recruited 144 patients (mean age 77.98, mean ACE-III 74.16, 124 with dementia, 20 with MCI). We diagnosed epilepsy in 25.7%: probable in 12.5% (17 with dementia, 1 with MCI), possible 13.2% (18 with dementia, 1 with MCI). Seizure features included altered responsiveness, speech/behavioural arrest, oral/pharyngeal automatism, olfactory/gustatory aura, focal motor seizure, other sensory phenomena (including hallucination), and amnesia on waking. Epilepsy prevalence was significantly increased in the dementia and MCI group vs controls (p = 0.004). Cognitive performance in the patient groups did not distinguish those in whom epilepsy was suspected from those in whom it was not. Patients in whom epilepsy was suspected were more impaired on informant completed measures of daily function. Conclusions: The prevalence of epilepsy is increased in dementia. The seizures are often subtle and easily missed. The presence of epilepsy predicts more severe impairment in the activities of daily living.Dunhill Medical Trus

Challenges and practical recommendations for successfully recruiting inactive, statin-free older adults to clinical trials

Objectives: To outline the challenges and provide practical recommendations for recruiting inactive, statin-free older adults to facilitate feasible study designs. Data was obtained from a double-blind randomised-controlled clinical trial investigating the effects of acipimox versus placebo on muscle function and metabolism in older (65-75 years), inactive, statin-free males. The initial recruitment target was 20 volunteers within 12 months (November 2016-November 2017). Results: Recruitment occurred via the Exeter 10,000 database containing 236 'eligible' males, a Facebook campaign reaching > 8000 ≥ 65 years old males, 400 directly-addressed letters to ≥ 66 year old males, > 1500 flyers distributed within the community, > 40 emails to local community groups, 4 recruitment talks, 2 magazine adverts and 1 radio advert. Widespread recruitment efforts reaching > 120,000 people led to the recruitment of 20 volunteers (18 completed the clinical trial) within a 25-month timeframe, highlighting the challenge of the timely recruitment of inactive, statin-free older adults for clinical trials. We recommend recruitment for future clinical trials should take a multi-pronged approach from the outset, prioritising the use of volunteer databases, Facebook campaigns and delivering recruitment talks.This article is freely available via Open Access. Click on the Publisher URL to access it via the publisher's site.This work was supported by a grant from Dunhill Medical Trust (R492/0516) and the NIHR Exeter CRF. CS Deane is a funded Medical Research Council Skills Development Fellow (MR/T026014/1). The funders had no role in study design, data analysis or outcome of the study.published version, accepted versio

Platinum-Gallium (Pt-Ga) Intermetallic Alloys for Propane Dehydrogenation

Natural gas is a source of energy for the United States. The Center for Innovative Strategic Transformation of Alkane Resources (CISTAR) plans to use shale gas extracted from shale rock formations as a bridge fuel to replace coal and oil while the US transitions to renewable energy like solar and wind. After methane, the largest components in shale gas are light alkanes such as ethane and propane. These can be catalytically converted to olefins, which can be further reacted to produce fuels, for example. Olefins from alkanes can be accomplished by dehydrogenation by promoted platinum alloys. This study compares the structure and chemical properties of Pt-Ga alloys on silica (SiO2) and ceria (CeO2) supports to determine if the support plays an important role in this chemistry. The catalysts containing different Pt:Ga ratios were synthesized using incipient wetness impregnation. These catalysts were characterized by in situ X-ray diffraction (XRD) and X-ray adsorption spectroscopy (XAS) to determine if an alloy was formed, and if so, the structure of that alloy. Finally, the catalysts were tested in a fixed bed reactor, where it was found that the silica-supported Pt-Ga alloy has a selectivity of \u3e90% towards propylene. Understanding catalyst design can lead to higher catalytic conversion of substances and potentially an improved selectivity for the formation of preferred products. Pt-Ga on ceria is tested for comparison and there appears to behave differently from that on silica demonstrating the importance of the role of the support on these catalysts

Short contact time CH4 partial oxidation over Ni based catalyst at 1.5MPa

Gas-to-liquid technologies to produce Fischer\u2013Tropsch fuels are economically sustainable at very large scales\u2014 30\u2008000bbld 121. To achieve a viable process at a scale less than 100bbld 121 requires a compact design, like a short contact time reactor and mass manufacturing to reduce capital cost. We tested the activity of 2.25%Ni/0.1%Ru/CeO2 supported on FeCrAl gauze (Ni2510) to partially oxide methane at a contact time less than 0.050s. Besides, the very short contact time, an additional feature of this work is that the catalyst activated on-stream without a hydrogen pretreatment step. The reactor operated at 1.5MPa, 800\ub0C\ua0to\ua0950\ub0C, and a CH4/O2 ratio varying from 1.6 to 1.8 v/v. Methane partially oxidized carbon monoxide (direct mechanism) rather than combusting to CO2 followed by steam reforming to CO (indirect mechanism). The following phenomena support the direct mechanism hypothesis: (i) the selectivity improved when reducing residence time, (ii) the mass spectrometer detected both O2 and CO at the effluent (simultaneously), (iii) metallic Ni clusters on the Ni2510 were absent under reaction conditions based on in situ X-ray absorption spectroscopy. Loading Ni/Al2O3 powder downstream of the Ni2510 increased syngas yield, as this catalyst promoted steam and dry reforming. Soot forms upstream of the Ni2510 catalyst via a retro-propagation mechanism in which methyl radicals produced on the catalyst surface react with the incoming feed gas

A Pyridinic Fe-N4 Macrocycle Effectively Models the Active Sites in Fe/N-Doped Carbon Electrocatalysts

Iron- and nitrogen-doped carbon (Fe-N-C) materials are leading candidates to replace platinum in fuel cells, but their active site structures are poorly understood. A leading postulate is that iron active sites in this class of materials exist in an Fe-N4 pyridinic ligation environment. Yet, molecular Fe-based catalysts for the oxygen reduction reaction (ORR) generally feature pyrrolic coordination and pyridinic Fe-N4 catalysts are, to the best of our knowledge, non-existent. We report the synthesis and characterization of a molecular pyridinic hexaazacyclophane macrocycle, (phen2N2)Fe, and compare its spectroscopic, electrochemical, and catalytic properties for oxygen reduction to a prototypical Fe-N-C material, as well as iron phthalocyanine, (Pc)Fe, and iron octaethylporphyrin, (OEP)Fe, prototypical pyrrolic iron macrocycles. N 1s XPS signatures for coordinated N atoms in (phen2N2)Fe are positively shifted relative to (Pc)Fe and (OEP)Fe, and overlay with those of Fe-N-C. Likewise, spectroscopic XAS signatures of (phen2N2)Fe are distinct from those of both (Pc)Fe and (OEP)Fe, and are remarkably similar to those of Fe-N-C with compressed Fe–N bond lengths of 1.97 Å in (phen2N2)Fe that are close to the average 1.94 Å length in Fe-N-C. Electrochemical studies establish that both (Pc)Fe and (phen2N2)Fe have relatively high Fe(III/II) potentials at ~0.6 V, ~300 mV positive of (OEP)Fe. The ORR onset potential is found to directly correlate with the Fe(III/II) potential leading to a ~300 mV positive shift in the onset of ORR for (Pc)Fe and (phen2N2)Fe relative to (OEP)Fe. Consequently, the ORR onset for (phen2N2)Fe and (Pc)Fe is within 150 mV of Fe-N-C. Unlike (OEP)Fe and (Pc)Fe, (phen2N2)Fe displays excellent selectivity for 4-electron ORR with 2O2 production, comparable to Fe-N-C materials. The aggregate spectroscopic and electrochemical data establish (phen2N2)Fe as a pyridinic iron macrocycle that effectively models Fe-N-C active sites, thereby providing a rich molecular platform for understanding this important class of catalytic materials.</p

A pyridinic Fe-N4 macrocycle models the active sites in Fe/N-doped carbon electrocatalysts

© 2020, The Author(s). Iron- and nitrogen-doped carbon (Fe-N-C) materials are leading candidates to replace platinum catalysts for the oxygen reduction reaction (ORR) in fuel cells; however, their active site structures remain poorly understood. A leading postulate is that the iron-containing active sites exist primarily in a pyridinic Fe-N4 ligation environment, yet, molecular model catalysts generally feature pyrrolic coordination. Herein, we report a molecular pyridinic hexaazacyclophane macrocycle, (phen2N2)Fe, and compare its spectroscopic, electrochemical, and catalytic properties for ORR to a typical Fe-N-C material and prototypical pyrrolic iron macrocycles. N 1s XPS and XAS signatures for (phen2N2)Fe are remarkably similar to those of Fe-N-C. Electrochemical studies reveal that (phen2N2)Fe has a relatively high Fe(III/II) potential with a correlated ORR onset potential within 150 mV of Fe-N-C. Unlike the pyrrolic macrocycles, (phen2N2)Fe displays excellent selectivity for four-electron ORR, comparable to Fe-N-C materials. The aggregate spectroscopic and electrochemical data demonstrate that (phen2N2)Fe is a more effective model of Fe-N-C active sites relative to the pyrrolic iron macrocycles, thereby establishing a new molecular platform that can aid understanding of this important class of catalytic materials

High-Capacitance Pseudocapacitors from Li+ Ion Intercalation in Nonporous, Electrically Conductive 2D Coordination Polymers

© Electrochemical capacitors (ECs) have emerged as reliable and fast-charging electrochemical energy storage devices that offer high power densities. Their use is still limited, nevertheless, by their relatively low energy density. Because high specific surface area and electrical conductivity are widely seen as key metrics for improving the energy density and overall performance of ECs, materials that have excellent electrical conductivities but are otherwise nonporous, such as coordination polymers (CPs), are often overlooked. Here, we report a new nonporous CP, Ni3(benzenehexathiolate) (Ni3BHT), which exhibits high electrical conductivity of over 500 S/m. When used as an electrode, Ni3BHT delivers excellent specific capacitances of 245 F/g and 426 F/cm3 in nonaqueous electrolytes. Structural and electrochemical studies relate the favorable performance to pseudocapacitive intercalation of Li+ ions between the 2D layers of Ni3BHT, a charge-storage mechanism that has thus far been documented only in inorganic materials such as TiO2, Nb2O5, and MXenes. This first demonstration of pseudocapacitive ion intercalation in nonporous CPs, a class of materials comprising thousands of members with distinct structures and compositions, provides important motivation for exploring this vast family of materials for nontraditional, high-energy pseudocapacitors