Imaging the Heterogeneity of the Oxygen Evolution Reaction on Gold Electrodes Operando: Activity is Highly Local

Understanding the mechanism of the oxygen evolution reaction (OER), the oxidative half of electrolytic water splitting, has proven challenging. Perhaps the largest hurdle has been gaining experimental insight into the active site of the electrocatalyst used to facilitate this chemistry. Decades of study have clarified that a range of transition-metal oxides have particularly high catalytic activity for the OER. Unfortunately, for virtually all of these materials, metal oxidation and the OER occur at similar potentials. As a result, catalyst surface topography and electronic structure are expected to continuously evolve under reactive conditions. Gaining experimental insight into the OER mechanism on such materials thus requires a tool that allows spatially resolved characterization of the OER activity. In this study, we overcome this formidable experimental challenge using second harmonic microscopy and electrochemical methods to characterize the spatial heterogeneity of OER activity on polycrystalline Au working electrodes. At moderately anodic potentials, we find that the OER activity of the electrode is dominated by <1% of the surface area and that there are two types of active sites. The first is observed at potentials positive of the OER onset and is stable under potential cycling (and thus presumably extends multiple layers into the bulk gold electrode). The second occurs at potentials negative of the OER onset and is removed by potential cycling (suggesting that it involves a structural motif only 1–2 Au layers deep). This type of active site is most easily understood as the catalytically active species (hydrous oxide) in the so-called incipient hydrous oxide/adatom mediator model of electrocatalysis. Combining the ability we demonstrate here to characterize the spatial heterogeneity of OER activity with a systematic program of electrode surface structural modification offers the possibility of creating a generation of OER electrocatalysts with unusually high activity

European clinical guidelines for Tourette syndrome and other tic disorders. Part II: pharmacological treatment

To develop a European guideline on pharmacologic treatment of Tourette syndrome (TS) the available literature was thoroughly screened and extensively discussed by a working group of the European Society for the Study of Tourette syndrome (ESSTS). Although there are many more studies on pharmacotherapy of TS than on behavioral treatment options, only a limited number of studies meets rigorous quality criteria. Therefore, we have devised a two-stage approach. First, we present the highest level of evidence by reporting the findings of existing Cochrane reviews in this field. Subsequently, we provide the first comprehensive overview of all reports on pharmacological treatment options for TS through a MEDLINE, PubMed, and EMBASE search for all studies that document the effect of pharmacological treatment of TS and other tic disorders between 1970 and November 2010. We present a summary of the current consensus on pharmacological treatment options for TS in Europe to guide the clinician in daily practice. This summary is, however, rather a status quo of a clinically helpful but merely low evidence guideline, mainly driven by expert experience and opinion, since rigorous experimental studies are scarce

Global overview of the management of acute cholecystitis during the COVID-19 pandemic (CHOLECOVID study)

Background: This study provides a global overview of the management of patients with acute cholecystitis during the initial phase of the COVID-19 pandemic. Methods: CHOLECOVID is an international, multicentre, observational comparative study of patients admitted to hospital with acute cholecystitis during the COVID-19 pandemic. Data on management were collected for a 2-month study interval coincident with the WHO declaration of the SARS-CoV-2 pandemic and compared with an equivalent pre-pandemic time interval. Mediation analysis examined the influence of SARS-COV-2 infection on 30-day mortality. Results: This study collected data on 9783 patients with acute cholecystitis admitted to 247 hospitals across the world. The pandemic was associated with reduced availability of surgical workforce and operating facilities globally, a significant shift to worse severity of disease, and increased use of conservative management. There was a reduction (both absolute and proportionate) in the number of patients undergoing cholecystectomy from 3095 patients (56.2 per cent) pre-pandemic to 1998 patients (46.2 per cent) during the pandemic but there was no difference in 30-day all-cause mortality after cholecystectomy comparing the pre-pandemic interval with the pandemic (13 patients (0.4 per cent) pre-pandemic to 13 patients (0.6 per cent) pandemic; P = 0.355). In mediation analysis, an admission with acute cholecystitis during the pandemic was associated with a non-significant increased risk of death (OR 1.29, 95 per cent c.i. 0.93 to 1.79, P = 0.121). Conclusion: CHOLECOVID provides a unique overview of the treatment of patients with cholecystitis across the globe during the first months of the SARS-CoV-2 pandemic. The study highlights the need for system resilience in retention of elective surgical activity. Cholecystectomy was associated with a low risk of mortality and deferral of treatment results in an increase in avoidable morbidity that represents the non-COVID cost of this pandemic

Slaap-waakstoornissen bij volwassenen met autisme in een klinische setting: Een pilotstudie [Sleep-wake patterns in adults with autism spectrum disorders in a clinical setting: A pilot study]

Contains fulltext : 175935.pdf (publisher's version ) (Open Access)Achtergrond: Ondanks de negatieve effecten van een slaap-waakstoornis in de algemene populatie en bij kinderen met een autismespectrumstoornis (ASS), is er weinig bekend over slaap-waakstoornissen bij volwassenen met ASS. Doel: Screenen op slaap-waakstoornissen en onderzoeken van slaap-waakpatronen middels objectieve en subjectieve metingen bij volwassenen met als primaire diagnose een ASS zonder comorbide cognitieve beperking in een klinische setting. Methode: De slaap werd bij 19 patiënten in een residentiële behandelsetting in kaart gebracht met een slaapanamnese, slaapdagboek en vragenlijsten (subjectieve meting) en actigraaf (objectieve meting) gedurende 7 dagen. Ook registreerden wij comorbide symptomen van angst- en stemmingsproblematiek en medicatiegebruik. Resultaten: Bij 9 patiënten (47%) constateerden wij een niet eerder gediagnosticeerde slaap-waakstoornis. De deelnemende patiënten overschatten hun slaapefficiëntie (slaapdagboek) vergeleken met objectieve data (actigrafie). De slaapbeleving kwam wel overeen met de objectief gemeten slaapefficiëntie. Hoewel 14 patiënten kenmerken van angst- en/of stemmingsproblematiek rapporteerden, was slechts bij 2 patiënten een comorbide depressieve stoornis gediagnosticeerd; 15 patiënten kregen psychofarmaca. Conclusie: Een slaap-waakstoornis en angst- en stemmingsklachten komen wellicht vaker voor bij volwassenen met ASS in de klinische populatie dan wordt gerapporteerd en verdienen meer aandacht bij diagnostiek en behandeling.8 p