Anticholinergic burden for prediction of cognitive decline or neuropsychiatric symptoms in older adults with mild cognitive impairment or dementia

Acknowledgements We would like to thank Dr Kate Wang, Dr Andrew Stafford, Ms Catherine Hofstetter, and Dr Joanna Damen for their helpful peer review comments on this protocol.Peer reviewedPublisher PD

Biomass pyrolysis TGA assessment with an international round robin

The large variations found in literature for the activation energy values of main biomass compounds (cellulose, hemicellulose and lignin) in pyrolysis TGA raise concerns regarding the reliability of both the experimental and the modelling side of the performed works. In this work, an international round robin has been conducted by 7 partners who performed TGA pyrolysis experiments of pure cellulose and beech wood at several heating rates. Deviations of around 20 – 30 kJ/mol were obtained in the activation energies of cellulose, hemicellulose and conversions up to 0.9 with beech wood when considering all experiments. The following method was employed to derive reliable kinetics: to first ensure that pure cellulose pyrolysis experiments from literature can be accurately reproduced, and then to conduct experiments at different heating rates and evaluate them with isoconversional methods to detect experiments that are outliers and to validate the reliability of the derived kinetics and employed reaction models with a fitting routine. The deviations in the activation energy values for the cases that followed this method, after disregarding other cases, were of 10 kJ/mol or lower, except for lignin and very high conversions. This method is therefore proposed in order to improve the consistency of data acquisition and kinetic analysis of TGA for biomass pyrolysis in literature, reducing the reported variability

Anticholinergic burden for prediction of cognitive decline or neuropsychiatric symptoms in older adults with mild cognitive impairment or dementia

Background: Medications with anticholinergic properties are commonly prescribed to older adults with a pre‐existing diagnosis of dementia or cognitive impairment. The cumulative anticholinergic effect of all the medications a person takes is referred to as the anticholinergic burden because of its potential to cause adverse effects. It is possible that a high anticholinergic burden may be a risk factor for further cognitive decline or neuropsychiatric disturbances in people with dementia. Neuropsychiatric disturbances are the most frequent complication of dementia that require hospitalisation, accounting for almost half of admissions; hence, identification of modifiable prognostic factors for these outcomes is crucial. There are various scales available to measure anticholinergic burden but agreement between them is often poor. Objectives: Our primary objective was to assess whether anticholinergic burden, as defined at the level of each individual scale, was a prognostic factor for further cognitive decline or neuropsychiatric disturbances in older adults with pre‐existing diagnoses of dementia or cognitive impairment. Our secondary objective was to investigate whether anticholinergic burden was a prognostic factor for other adverse clinical outcomes, including mortality, impaired physical function, and institutionalisation. Search methods: We searched these databases from inception to 29 November 2021: MEDLINE OvidSP, Embase OvidSP, PsycINFO OvidSP, CINAHL EBSCOhost, and ISI Web of Science Core Collection on ISI Web of Science. Selection criteria: We included prospective and retrospective longitudinal cohort and case‐control observational studies, with a minimum of one‐month follow‐up, which examined the association between an anticholinergic burden measurement scale and the above stated adverse clinical outcomes, in older adults with pre‐existing diagnoses of dementia or cognitive impairment. Data collection and analysis: Two review authors independently assessed studies for inclusion, and undertook data extraction, risk of bias assessment, and GRADE assessment. We summarised risk associations between anticholinergic burden and all clinical outcomes in a narrative fashion. We also evaluated the risk association between anticholinergic burden and mortality using a random‐effects meta‐analysis. We established adjusted pooled rates for the anticholinergic cognitive burden (ACB) scale; then, as an exploratory analysis, established pooled rates on the prespecified association across scales. Main results: We identified 18 studies that met our inclusion criteria (102,684 older adults). Anticholinergic burden was measured using five distinct measurement scales: 12 studies used the ACB scale; 3 studies used the Anticholinergic Risk Scale (ARS); 1 study used the Anticholinergic Drug Scale (ADS); 1 study used the Anticholinergic Effect on Cognition (AEC) Scale; and 2 studies used a list developed by Tune and Egeli. Risk associations between anticholinergic burden and adverse clinical outcomes were highly heterogenous. Four out of 10 (40%) studies reported a significantly increased risk of greater long‐term cognitive decline for participants with an anticholinergic burden compared to participants with no or minimal anticholinergic burden. No studies investigated neuropsychiatric disturbance outcomes. One out of four studies (25%) reported a significant association with reduced physical function for participants with an anticholinergic burden versus participants with no or minimal anticholinergic burden. No study (out of one investigating study) reported a significant association between anticholinergic burden and risk of institutionalisation. Six out of 10 studies (60%) found a significantly increased risk of mortality for those with an anticholinergic burden compared to those with no or minimal anticholinergic burden. Pooled analysis of adjusted mortality hazard ratios (HR) measured anticholinergic burden with the ACB scale, and suggested a significantly increased risk of death for those with a high ACB score relative to those with no or minimal ACB scores (HR 1.153, 95% confidence interval (CI) 1.030 to 1.292; 4 studies, 48,663 participants). An exploratory pooled analysis of adjusted mortality HRs across anticholinergic burden scales also suggested a significantly increased risk of death for those with a high anticholinergic burden (HR 1.102, 95% CI 1.044 to 1.163; 6 studies, 68,381 participants). Overall GRADE evaluation of results found low‐ or very low‐certainty evidence for all outcomes. Authors' conclusions: There is low‐certainty evidence that older adults with dementia or cognitive impairment who have a significant anticholinergic burden may be at increased risk of death. No firm conclusions can be drawn for risk of accelerated cognitive decline, neuropsychiatric disturbances, decline in physical function, or institutionalisation

Παραγωγή Η2 μέσω της διάσπασης του H2S της Μαύρης Θάλασσας σε συμβατικούς καταλυτικούς μετατροπείς και σε αντιδραστήρες μεμβράνης στερεού ηλεκτρολύτη αγωγών πρωτονίων

The emerging energy and environmental concerns have recently forced the society to utilize “clean” energy resources and develop efficient energy conversion technologies. Hydrogen sulfide (H2S) is abundantly found in Black Sea waters and hails as an important H2 source, while its efficient removal from Black Sea waters will protect the surrounding ecosystem. Various processes have been suggested to produce hydrogen from H2S decomposition, which are currently at different stages of development. The most commonly employed method is the catalytic decomposition of H2S, which however takes place at high temperatures in order to achieve conversions exceeding 80%. A novel approach based on stable ceramic H+ conducting electrochemical reactor is proposed here, which could also act as a method to eliminate H2S emissions in petroleum hydro-treatment operations, natural gas and coal gasification industries. In the present PhD thesis, H2S electrolysis is carried out in a proton-conducting ceramic electrochemical membrane reactor. In specific, H2S diluted in excess H2O (simulating the mixture derived from Black Sea waters) is fed at the anode, while the cathode is exposed to oxidizing conditions. When an anodic overpotential is applied, H2S and H2O are electrolyzed producing H+, which are transferred to cathode where the evolution of H2 takes place. Thus, pure H2 is generated and separated in a single stage. In such a complex process, the major issue is to identify efficient and stable catalyst composites to be applied as anode material for this reactor. In this context and prior to the electrochemical tests, a series of catalysts, namely, i) 20 wt.% Cu supported REOs (Cu/REOs), ii) 20 wt.% Cu supported Ce1-xSmxOδ (20 wt.% Cu/Ce1-xSmxOδ ), iii) ceria supported transition metal (Co, Ni, Fe and Cu) and iv) bimetallic (Cu20-xCox/CeO2) (x = 0, 5, 10, 15, 20 wt.%), were synthesized via the wet impregnation method and evaluated in terms of their activity and stability towards H2S decomposition in the absence/presence of excess H2O. The Co/CeO2 sample demonstrated the optimum activity and stability performance both in absence and presence of H2O, reaching H2S conversions close to those predicted by the reaction equilibrium (34% at 850 oC). An initial activation period was found to be necessary for the establishment of a steady-state, due to the progressive reduction/sulfation of the catalyst’s counterparts under the reaction conditions. The superior behaviour of the Co3O4/CeO2 catalyst was attributed to the in-situ formation of highly active and stable sulfated phases (i.e., Co1-xSy and Ce10S14Oy) from its counterparts during the H2S decomposition reaction. In general, the optimization of suitable electrode materials is a fundamental step in the development of tolerant and efficient electrochemical membrane reactor cells. In this work, BaZr0.7Ce0.2Y0.1O3 (BZCY72) was selected as the solid electrolyte and Co3O4-CeO2 mixed oxide was employed as the anodic electrode, while BaGd0.8La0.2Co2O6-δ (BGLC) perovskite was used as the cathode. Various methods and thermal treatments were examined to fabricate a conductive cell, which was physicochemically characterized with XRD and SEM methods. The corresponding electrochemical characterization involved polarization, AC impedance and electrocatalytic studies under H2/H2O and H2S/H2O mixtures at 900-1200 K and atmospheric pressure. It was revealed that, in the presence of H2/H2O, the optimum performance was achieved at T = 850 oC, pH2 = 10 kPa and pH2O = 2.5 kPa with an ohmic resistance of 22 Ohm.cm2 and polarization resistance equal to 8 Ohm.cm2. The most crucial step affecting the electrode performance was found to be the diffusion of protons to the electrochemical active three-phase boundary (electrode/electrolyte/gas phase), which was additionally hindered at high hydrogen and steam partial pressures due to the charge space effect. In the presence of H2S/H2O, cobalt and cerium were in-situ converted to sulphides, which presented a beneficial effect on the performance and durability of the cell, thus leading to a strong increase of conductivity. In addition the in-situ rearrangement of conductive phases improved the in plane conductivity leading to higher proton fluxes. A high electrochemical performance is a prerequisite for the implementation of the present electrochemical-aided concept, opening new horizons for the efficient management of H2S-containing streams in industrial (refineries) and natural (Black Sea, geothermal wells) sources.Finally, the feasibility of an integrated scaled up process towards the remediation of the Black Sea ecosystem and H2 generation through the co-electrolysis of rich H2S/H2O mixtures was examined. Two different process flow diagrams were developed and assessed depending on the downstream management options of the generated SO2 by-product. Both process flow diagrams were assessed in terms of operating flexibility, electricity/heat requirements and economic criteria. It was found that the proposed technology is initially far from economically affordable for any investor. On the other hand, as it was thoroughly discussed in the present thesis, the utilization of Black Sea H2S is stimulated more from environmental and social motivations than from economic. Though, taking into account the great emphasis given by the European and the nearby countries on the amelioration of the Black Sea ecosystem, an additional “optimized” scenario is assessed to realistically evaluate the technical, economical and, in the same time, the environmental sustainability of the designed plants.Οι παγκόσμιες απαιτήσεις σε ενέργεια βαίνουν διαρκώς αυξανόμενες εξαιτίας της συνεχούς αύξησης του πληθυσμού, της ανάπτυξης και του βιοτικού επιπέδου. Συνεπώς, νέες πηγές ενέργειας, καθαρές και σε αφθονία, πρέπει να υιοθετηθούν για την κάλυψη των παγκόσμιων ενεργειακών αναγκών. Το υδρογόνο (H2) ως καύσιμο μπορεί να αποτελέσει σημαντικό ενεργειακό φορέα στο μέλλον. Προς την κατεύθυνση αυτή το υδρόθειο (Η2S), το οποίο βρίσκεται σε αφθονία στα ύδατα του Εύξεινου Πόντου, παρά τις επιβλαβείς επιπτώσεις στην ανθρώπινη υγεία και στο οικοσύστημα της Μαύρης Θάλασσας μπορεί να αποτελέσει μια αξιόπιστη μελλοντική πηγή ενέργειας. H παραγωγή Η2 από H2S μπορεί να επιτευχθεί με τη χρήση διαφόρων διεργασιών, με την ηλεκτροχημική μέθοδο να θεωρείται ως η πλέον υποσχόμενη προσέγγιση προς τη ζητούμενη κατεύθυνση. Ειδικότερα, οι ηλεκτροχημικοί αντιδραστήρες μεμβράνης στερεού ηλεκτρολύτη αγωγού πρωτονίων μπορούν να αποτελέσουν μια πολύ αποτελεσματική και ταυτόχρονα οικονομική λύση για την παραγωγή Η2 από H2S. Καθοριστικής σημασίας προς την ανάπτυξη της προτεινόμενης μεθόδου αποτελεί ωστόσο η σύνθεση καινοτόμων υλικών, τα οποία θα επιδεικνύουν υψηλή ηλεκτρονιακή αγωγιμότητα, ηλεκτροκαταλυτική ενεργότητα και θα ανθίστανται στην παρουσία H2S, προκειμένου να χρησιμοποιηθούν ως ανοδικά ηλεκτρόδια κατά την ηλεκτροχημική διάσπαση του Η2S προς Η2. Στο πλαίσιο αυτό, και πριν από τις ηλεκτροχημικές δοκιμές, στην παρούσα διδακτορική διατριβή εξετάστηκε αρχικά η καταλυτική διάσπαση του H2S απουσία και παρουσία περίσσειας H2O σε μια σειρά καταλυτικών συστημάτων (20 κ.β.% Cu/REOs, 20 κ.β.% Cu/Ce1-xSmxOδ, 20 κ.β.% M/CeO2, Cu20-xCox/CeO2). Η αξιολόγηση τους υπέδειξε την υπεροχή των καταλυτών Co/CeO2, τόσο ως προς την ενεργότητα, όσο και ως προς την σταθερότητα τους, καθώς επέτυχαν τις υψηλότερες μετατροπές σε όλο το εύρος των θερμοκρασιών, καθώς επίσης και αξιοσημείωτη σταθερότητα. Η ανωτερότητα τους αποδίδεται στα εν γένη χαρακτηριστικά του Co και στον επί τόπου σχηματισμό θειούχων ενώσεων (Co1-xSy and Ce10S14Oy) από τα αρχικά συστατικά του καταλύτη, οι οποίες εμφανίζονται εξαιρετικά δραστικές και σταθερές κατά τη καταλυτική διάσπαση του H2S προς παραγωγή Η2.Σε μια τόσο πολύπλοκη διαδικασία, ένα από τα σημαντικότερα ζητήματα όπως αναφέρθηκε παραπάνω, είναι η επιλογή των βέλτιστων υλικών του ηλεκτροχημικού αντιδραστήρα. Βάσει όλων των παραπάνω τελικώς αναπτύχθηκαν μικτά οξείδια Co3O4-CeO2 τα οποία χρησιμοποιήθηκαν ως ανοδικά ηλεκτρόδια, ενώ ως στερεός ηλεκτρολύτης επιλέχθηκε ο BaZr0.7Ce0.2Y0.1O3 (ΒΖCY72) και ως κάθοδος χρησιμοποιήθηκε ο περοβσκίτης BaGd0.8La0.2Co2O6-δ (BGLC). Αρχικά, πραγματοποιήθηκε ο φυσικοχημικός χαρακτηρισμός των οξειδίων προκειμένου να αναγνωριστούν τα βασικά δομικά χαρακτηριστικά τους. Στην συνέχεια ακολούθησε ο ηλεκτροχημικός χαρακτηρισμός σε αντιδρώντα μίγματα H2/H2O και H2S/H2O, σε θερμοκρασιακό εύρος 650-850 οC και σε ατμοσφαιρική πίεση. Διαπιστώθηκε ότι παρουσία Η2/Η2Ο η βέλτιστη απόδοση επιτεύχθηκε στους Τ = 850 οC, pΗ2 = 10 kPa και pΗ2Ο = 2,5 kPa, με ωμική αντίσταση 22 Ohm.cm2 και αντίσταση πόλωσης ίση με 8 Ohm.cm2. Βρέθηκε ότι το κύριο στάδιο που επηρεάζει την διεπιφανειακή (ηλεκτρόδιο/ηλεκτρολύτης) αντίσταση ήταν η διάχυση των πρωτονίων προς την ηλεκτροχημικά ενεργή τριεπιφάνεια. Παρουσία H2S/H2O, τόσο το Co3O4 όσο και το CeO2 μετατράπηκαν σε σουλφίδια, τα οποία παρουσίασαν ευεργετική επίδραση στην ηλεκτροχημική απόδοση και ανθεκτικότητα του συστήματος. Τα ιδιαίτερα ενθαρρυντικά αποτελέσματα παρουσία H2S αποδόθηκαν εκτός από την θείωση των συστατικών του ηλεκτροδίου και στην αναδιάταξη των αγώγιμων φάσεων του ηλεκτροδίου συμβάλλοντας στην επέκταση της ηλεκτροχημικά ενεργής ζώνης σε σχέση με το ηλεκτρόδιο Co3O4/CeO2 απουσία μιγμάτων H2S. Η υψηλή αγωγιμότητα αποτελεί αναγκαία προϋπόθεση για την εφαρμογή αυτού του υλικού ως ηλεκτρόδιο, ανοίγοντας νέους ορίζοντες για την αποτελεσματική διαχείριση βιομηχανικών (διυλυστήρια) ή φυσικών (Μαύρη Θάλλασα, γεωθερμικές πηγές) μιγμάτων που περιέχουν H2S.Τέλος, στην παρούσα εργασία παρουσιάσθηκε μία ολοκληρωμένη μελέτη σχεδιασμού ενός αυτόνομου συστήματος παραγωγής υδρογόνου μέσω διάσπασης Η2S, προερχόμενο από τη Μαύρη Θάλασσα, με σκοπό τόσο την αποκατάσταση του οικοσυστήματος της, όσο και της παραγωγής Η2 μέσω της ταυτόχρονης ηλεκτρόλυσης μιγμάτων H2S/H2O. Δύο διαφορετικά διαγράμματα ροής αναπτύχθηκαν και αξιολογήθηκαν από άποψη λειτουργικής ευελιξίας, απαιτήσεων ηλεκτρικής ενέργειας/θερμότητας και οικονομικών κριτηρίων, ως προς τη διαχείριση του παραγόμενου παραπροϊόντος SO2. Αρχικά, διαπιστώθηκε πως η προτεινόμενη τεχνολογία είναι μη οικονομικά προσιτή για κάθε επενδυτή. Όμως, έχοντας ως γνώμονα, όπως αναλύεται διεξοδικά στην παρούσα διατριβή, πως η χρήση του H2S της Μαύρης Θάλασσας είναι περισσότερο υποκινούμενη από περιβαλλοντικά και κοινωνικά κίνητρα παρά από οικονομικά και λαμβάνοντας υπόψη το μεγάλο ενδιαφέρον που δίνουν οι ευρωπαϊκές και οι γειτονικές χώρες για τη βελτίωση του οικοσυστήματος της Μαύρης Θάλασσας, αξιολογείται ένα πρόσθετο «βελτιστοποιημένο» σενάριο για τη ρεαλιστική αποτίμηση της τεχνικής, οικονομικής και ταυτόχρονα περιβαλλοντικής βιωσιμότητας της προτεινόμενης μελέτης

H

The present study aims to examine and evaluate the concept of H2S decomposition to H2 production in (H2)-conducting electrochemical reactors. In such a complex process, one of the major issues raised is the optimal selection of materials for the electrochemical cell. Specifically, the anode electrode should exhibit high catalytic activity and electronic conductivity, in order to make the process efficient. In this context, and before the electrochemical tests, a number of transition metal catalysts supported on CeO2 were prepared using the wet impregnation method and tested for their performance regarding the activity/stability of the H2S decomposition reaction, in the absence and presence of H2O. The experimental results are accompanied by the corresponding thermodynamic calculations, at various reaction conditions. The physico-chemical characteristics of the employed catalysts were determined using the BET, XRD, SEM and elemental analysis methods. The experimental results showed that the catalysts 20% wt. Co/CeO2 and 30% wt. Co/CeO2 exhibit high H2S conversions, in the absence and presence of H2O respectively, comparable to conversions indicated by thermodynamics and with remarkable stability, which is attributed to the in-situ sulfation of catalysts’ active components during their exposure at the feedstock mixture

H2S in Black Sea: Turning an environmental threat to an opportunity for clean H2 production via an Electrochemical Membrane Reactor. Research progress in H2S-PROTON Project

The present study aims to examine and evaluate the concept of H2S decomposition to H2 production in (H2)-conducting electrochemical reactors. In such a complex process, one of the major issues raised is the optimal selection of materials for the electrochemical cell. Specifically, the anode electrode should exhibit high catalytic activity and electronic conductivity, in order to make the process efficient. In this context, and before the electrochemical tests, a number of transition metal catalysts supported on CeO2 were prepared using the wet impregnation method and tested for their performance regarding the activity/stability of the H2S decomposition reaction, in the absence and presence of H2O. The experimental results are accompanied by the corresponding thermodynamic calculations, at various reaction conditions. The physico-chemical characteristics of the employed catalysts were determined using the BET, XRD, SEM and elemental analysis methods. The experimental results showed that the catalysts 20% wt. Co/CeO2 and 30% wt. Co/CeO2 exhibit high H2S conversions, in the absence and presence of H2O respectively, comparable to conversions indicated by thermodynamics and with remarkable stability, which is attributed to the in-situ sulfation of catalysts’ active components during their exposure at the feedstock mixture

Hydrogen Production by Ethanol Steam Reforming (ESR) over CeO2 Supported Transition Metal (Fe, Co, Ni, Cu) Catalysts: Insight into the Structure-Activity Relationship

The aim of the present work was to investigate steam reforming of ethanol with regard to H2 production over transition metal catalysts supported on CeO2. Various parameters concerning the effect of temperature (400–800 °C), steam-to-carbon (S/C) feed ratio (0.5, 1.5, 3, 6), metal entity (Fe, Co, Ni, Cu) and metal loading (15–30 wt.%) on the catalytic performance, were thoroughly studied. The optimal performance was obtained for the 20 wt.% Co/CeO2 catalyst, achieving a H2 yield of up to 66% at 400 °C. In addition, the Co/CeO2 catalyst demonstrated excellent stability performance in the whole examined temperature range of 400–800 °C. In contrast, a notable stability degradation, especially at low temperatures, was observed for Ni-, Cu-, and Fe-based catalysts, ascribed mainly to carbon deposition. An extensive characterization study, involving N2 adsorption-desorption (BET), X-ray diffraction (XRD), Scanning Electron Microscopy (SEM/EDS), X-ray Photoelectron Spectroscopy (XPS), and Temperature Programmed Reduction (H2-TPR) was undertaken to gain insight into the structure-activity correlation. The excellent reforming performance of Co/CeO2 catalysts could be attributed to their intrinsic reactivity towards ethanol reforming in combination to their high surface oxygen concentration, which hinders the deposition of carbonaceous species

Electrochemical performance of Co3O4/CeO2 electrodes in H2S/H2O atmospheres in a proton-conducting ceramic symmetrical cell with BaZr0.7Ce0.2Y0.1O3 solid electrolyte

The electrochemical performance of Co3O4/CeO2 mixed oxide materials as electrodes, when exposed to H2S/H2O atmospheres, was examined employing a proton conducting symmetrical cell, with BaZr0.7Ce0.2Y0.1O3 (BZCY72) as the solid electrolyte. The impact of temperature (700–850 °C) and H2S concentration (0–1 v/v%) in steam-rich atmospheres (90 v/v% H2O) on the overall cell performance was thoroughly assessed by means of electrochemical impedance spectroscopy (EIS) studies. The performance of the Co3O4/CeO2 electrode was significantly enhanced by increasing the H2S concentration and temperature. The obtained results were interpreted on the basis of EIS results and physicochemical characterization (XRD, SEM) studies of fresh and used electrodes. Notably, it was found that the mass transport processes, mainly associated with the adsorption and diffusion of the intermediate species resulting by the chemical and half-cell reactions taking place during cell operation, dominate the electrode polarization resistance compared with the charge transfer processes. Upon increasing temperature and H2S concentration, the electrode resistance is substantially lowered, due to the in situ activation and morphological modifications of the electrode, induced by its interaction with the reactants (H2S/H2O) and products (H2/SO2) mixtures