Platinum ineligibility and survival outcomes in patients with advanced urothelial carcinoma receiving first-line treatment.

BACKGROUND: This study examined real-world patients with locally advanced or metastatic urothelial carcinoma considered ineligible for platinum-containing chemotherapy in the first-line setting. METHODS: This retrospective observational study used data from a nationwide (United States) de-identified patient-level electronic health record-derived database. Eligible adults (aged 18 years and older) had a locally advanced or metastatic urothelial carcinoma diagnosis on or after January 1, 2016, and initiated first-line systemic treatment at least 90 days before December 31, 2021. Platinum ineligibility was defined as Eastern Cooperative Oncology Group performance status of at least 3, creatinine clearance less than 30 mL/min, or Eastern Cooperative Oncology Group performance status of 2 and creatinine clearance of less than 45 mL/min. Overall survival and real-world progression-free survival (PFS) were summarized using the Kaplan-Meier method. RESULTS: The overall population comprised 4270 patients; 477 (11%) were considered platinum ineligible, 262 (55%) received a first-line programmed cell death 1 or programmed cell death ligand 1 immune checkpoint inhibitor, and 118 (25%) received platinum-based chemotherapy. A total of 2335 (55%) patients were platinum eligible; 677 (29%) received a first-line programmed cell death 1 or programmed cell death ligand 1 inhibitor, and 1229 (53%) received platinum-based chemotherapy. Median overall survival was 13.3 months (95% confidence interval [CI] = 12.4 to 14.8 months) in platinum-eligible and 5.1 months (95% CI = 4.2 to 6.4 months) in platinum-ineligible patients. Median PFS was shorter in platinum-ineligible (3.4 months; 95% CI = 2.9 to 4.0 months) vs platinum-eligible patients (5.9 months; 95% CI = 5.5 to 6.2 months) overall and when stratified by first-line therapy type. CONCLUSION: This real-world study has shown for the first time the treatment patterns and outcomes in newly diagnosed patients with locally advanced or metastatic urothelial carcinoma ineligible for platinum-based chemotherapy. These findings provide quantitative benchmarks for platinum ineligibility in the first-line advanced or metastatic urothelial carcinoma setting and highlight the need for novel therapy options.

Gender, loneliness and happiness during COVID-19.

We analyse a measure of loneliness from a representative sample of German individuals interviewed in both 2017 and at the beginning of the COVID-19 pandemic in 2020. Both men and women felt lonelier during the COVID-19 pandemic than they did in 2017. The pandemic more than doubled the gender loneliness gap: women were lonelier than men in 2017, and the 2017-2020 rise in loneliness was far larger for women. This rise is mirrored in life-satisfaction scores. Men's life satisfaction changed only little between 2017 and 2020; yet that of women fell dramatically, and sufficiently so to produce a female penalty in life satisfaction. We estimate that almost all of this female penalty is explained by the disproportionate rise in loneliness for women during the COVID-19 pandemic.

Adsorption and keto-enol-tautomerisation of butanal on Pd(111).

Microscopic-level understanding of the interaction of hydrocarbons with transition metal surfaces is an important prerequisite for rational design of new materials with improved catalytic properties. In this report, we present a mechanistic study on the keto-enol tautomerisation of butanal on Pd(111), which was theoretically predicted to play a crucial role in low-barrier hydrogenation of carbonyl compounds. These processes were addressed by a combination of reflection-absorption infrared spectroscopy, molecular beam techniques and theoretical calculations at the density functional theory level. Spectroscopic information obtained on Pd(111) suggests that butanal forms three different aldehyde species, which we indicate as A1-A3 as well as their enol counterpart E1. The electronically strongest perturbed and strongest binding species A1 is most likely related to the η2(C,O) adsorption configuration, in which both C and O atoms are involved in the bonding with the underlying metal. The species A2 weakly binds and is less electronically perturbed and can be associated with the η1(O) adsorption configuration. The third type of aldehyde species A3, which is nearly unperturbed and is found only at low temperatures, results from the formation of the butanal multilayer. Importantly, the enol form of butanal was observed on the surface, which gives rise to a new characteristic band at 1104 cm-1 related to the stretching vibration of the C-O single bond (ν(C-O)). With increasing temperature, the multi-layer related species A3 disappears from the surface above 136 K. The population of aldehyde species A1 and the enol species E1 noticeably increases with increasing temperature, while the band related to the aldehyde species A2 becomes strongly attenuated and finally completely disappears above 120 K. These observations suggest that species E1 and A1 are formed in an activated process and - in view of the strongly anti-correlated population of the species E1 and A2 - it can be concluded that enol species E1 is most likely formed from the weakly bound aldehyde species A2 (η1(O)). Finally, we discuss the possible routes to enol stabilization via intermolecular bonding and provide the possible structure of the enol-containing stabilized complex, which is compatible with all spectroscopic observations. The obtained results provide important insights into the process of keto-enol tautomerisation of simple carbonyl compounds.

Clinico-Genomic Characterization of Patients with Metastatic Urothelial Carcinoma in Real-World Practice Identifies a Novel Bladder Immune Performance Index (BIPI).

PURPOSE: This retrospective analysis of the largest available clinico-genomic database used de-identified patient-level electronic health record-derived real-world data (RWD) combined with FoundationOne comprehensive genomic profiling (CGP) to characterize patients with metastatic urothelial carcinoma (mUC) treated in the real-world setting, detect potential biomarkers, and develop a bladder immune performance index (BIPI). EXPERIMENTAL DESIGN: Patients with mUC who started front-line single-agent immune checkpoint inhibitors (ICI) and an unmatched group treated with front-line platinum-based chemotherapy between January 1, 2011, and September 30, 2019, were selected. Clinical and genomic data were correlated with overall survival (OS). A novel BIPI predicting outcome with ICIs was developed using machine learning methods and validated using data from a phase II trial (NCT02951767). RESULTS: In ICI-treated patients (n = 118), high tumor mutational burden (≥10 mutations/megabase) was associated with improved OS (HR, 0.58; 95% CI, 0.35-0.95; P = 0.03). In chemotherapy-treated patients (n = 268), those with high APOBEC mutational signature had worse OS (HR, 1.43; 95% CI, 1.06-1.94; P = 0.02). Neither FGFR3 mutations nor DNA damage-repair pathway alterations were associated with OS. A novel BIPI combining clinical and genomic variables (nonmetastatic at initial diagnosis, normal or above normal albumin level at baseline, prior surgery for organ-confined disease, high tumor mutational burden) identified ICI-treated patients with longest OS and was validated in an independent dataset. CONCLUSIONS: Contemporary RWD including FoundationOne CGP can be used to characterize outcomes in real-world patients according to biomarkers beyond PD-L1. A validated, novel clinico-genomic BIPI demonstrated satisfactory prognostic performance for OS in patients with mUC receiving front-line ICI therapy.

Social Norms and Preventive Behaviors in Japan and Germany During the COVID-19 Pandemic.

Background: According to a recent paper by Gelfand et al., COVID-19 infection and case mortality rates are closely connected to the strength of social norms: "Tighter" cultures that abide by strict social norms are more successful in combating the pandemic than "looser" cultures that are more permissive. However, countries with similar levels of cultural tightness exhibit big differences in mortality rates. We are investigating potential explanations for this fact. Using data from Germany and Japan-two "tight" countries with very different infection and mortality rates-we examined how differences in socio-demographic and other determinants explain differences in individual preventive attitudes and behaviors. Methods: We compared preventive attitudes and behaviors in 2020 based on real-time representative survey data and used logit regression models to study how individual attitudes and behaviors are shaped by four sets of covariates: individual socio-demographics, health, personality, and regional-level controls. Employing Blinder-Oaxaca regression techniques, we quantified the extent to which differences in averages of the covariates between Japan and Germany explain the differences in the observed preventive attitudes and behaviors. Results: In Germany and Japan, similar proportions of the population supported mandatory vaccination, avoided travel, and avoided people with symptoms of a cold. In Germany, however, a significantly higher proportion washed their hands frequently and avoided crowds, physical contact, public transport, peak-hour shopping, and contact with the elderly. In Japan, a significantly higher proportion were willing to be vaccinated. We also show that attitudes and behaviors varied significantly more with covariates in Germany than in Japan. Differences in averages of the covariates contribute little to explaining the observed differences in preventive attitudes and behaviors between the two countries. Conclusion: Consistent with tightness-looseness theory, the populations of Japan and Germany responded similarly to the pandemic. The observed differences in infection and fatality rates therefore cannot be explained by differences in behavior. The major difference in attitudes is the willingness to be vaccinated, which was much higher in Japan. Furthermore, the Japanese population behaved more uniformly across social groups than the German population. This difference in the degree of homogeneity has important implications for the effectiveness of policy measures during the pandemic.

Attitudes Toward Mandatory COVID-19 Vaccination in Germany.

BACKGROUND: Adequate immunity to COVID-19 apparently cannot be attained in Germany by voluntary vaccination alone, and therefore the introduction of mandatory COVID-19 vaccination is still under consideration. We present findings on the potential acceptance of such a requirement by the German population, and we report on the reasons given for accepting or rejecting it and how these reasons vary according to population subgroup. METHODS: We used representative data from the Socio-Economic Panel for the period January to December 2021. We linked the respondents' answers concerning mandatory COVID-19 vaccination to information about their sociodemographic characteristics, state of health, political attitudes, and degree of confidence in the judicial and political systems. We analyzed these data using univariate, bivariate, and multivariate statistical methods. RESULTS: Just over half of the respondents (50.44% [49.08%; 51.79%]) favored mandatory COVID-19 vaccination. Among the supporters, the reason most frequently given (95.22% [94.45; 96.00]) was that, without such a requirement, not enough people would be vaccinated. Among the opponents of mandatory COVID-19 vaccination (49.56% [48.21%; 50.92%]), by far the most common reason given for opposing it was a desire to uphold individual freedom (91.36% [90.31%; 92.40%]). Persons supporting mandatory COVID-19 vaccination, on average, older than those who opposed it; they less commonly had an education beyond secondary school, were less healthy, tended to have no children, had centrist political views, and expressed more confidence in the political system. The largest difference between the two groups was that about 90% of supporters of mandatory COVID-19 vaccination were themselves vaccinated, compared to only about 62% of opponents. CONCLUSION: The lack of consensus on this issue among politicians and physicians in Germany is reflected in a similar lack of consensus in the German population as a whole. A discussion of the appropriate understanding of individual freedom would be the most promising way to widen the acceptance of mandatory COVID-19 vaccination. A commonly expressed conception of freedom that permits the deliberate endangerment of other people's health seems morally questionable.

Natural History of Human Epidermal Growth Factor Receptor 2-Amplified and Human Epidermal Growth Factor Receptor 2 Wild-Type Refractory Metastatic Colorectal Cancer in US Clinical Practice.

PURPOSE: The molecular heterogeneity of metastatic colorectal cancer (mCRC) presents a therapeutic challenge, with few trials focused on patients with human epidermal growth factor receptor 2 amplification (HER2-Amp). Our limited understanding of real-world patterns and outcomes by HER2 status of treatment-refractory patients leaves treatment decisions with little contextual information. We conducted a retrospective cohort study to describe the natural disease history of patients with refractory mCRC using an electronic health record-derived database with oncogenomic information. METHODS: We included patients with stage IV or recurrent mCRC diagnosed from January 2011 through December 2019 from a deidentified clinicogenomic database. Patients with ≥ 2 documented clinic visits, ≥ 2 lines of therapy (LOT) after mCRC diagnosis, and comprehensive genomic profiling were eligible. Patient records defined by treatment-refractory LOT were allocated to the HER2-Amp or HER2 wild-type (WT) cohort on the basis of comprehensive genomic profiling. Index date was defined as the start of any treatment-refractory LOT (≥ 2 LOT; patients could contribute multiple records). Descriptive statistics included demographic and clinical characteristics, treatments, laboratory values, and biomarkers. Overall survival (OS) was calculated as time (in months) from the index date until death from any cause and analyzed using Kaplan-Meier methodology. Sensitivity analyses were conducted to test the robustness of the primary findings. RESULTS: A total of 576 patients were included (1,339 records); 63 (158 records) were HER2-Amp, and 513 (1,181 records) were HER2-WT. Demographics, clinical characteristics, biomarkers, and laboratory values were comparable between HER2 cohorts. OS was similar, with an unadjusted median OS of 11.2 months (95% CI, 8.6 to 15.1) and 9.9 months (95% CI, 8.3 to 10.9) across LOT for HER2-Amp and HER2-WT cohorts, respectively. CONCLUSION: This study showed considerable treatment heterogeneity and poor outcomes among patients with treatment-refractory mCRC, emphasizing a substantial unmet therapeutic need.

Socioeconomic position and SARS-CoV-2 infections: seroepidemiological findings from a German nationwide dynamic cohort.

BACKGROUND: Evidence on the relationship between socioeconomic position (SEP) and infections with SARS-CoV-2 is still limited as most of the available studies are ecological in nature. This is the first German nationwide study to examine differences in the risk of SARS-CoV-2 infections according to SEP at the individual level. METHODS: The 'CORONA-MONITORING bundesweit' (RKI-SOEP) study is a seroepidemiological survey among a dynamic cohort of the German adult population (n=15 122; October 2020-February 2021). Dried blood samples were tested for SARS-CoV-2 antibodies and oral-nasal swabs for viral RNA. SEP was measured by education and income. Robust logistic regression was used to examine adjusted associations of SARS-CoV-2 infections with SEP. RESULTS: 288 participants were seropositive, PCR positive or self-reported a previous laboratory-confirmed SARS-CoV-2 infection. The adjusted odds of SARS-CoV-2 infection were 1.87-fold (95% CI 1.06 to 3.29) higher among low-educated than highly educated adults. Evidence was weaker for income differences in infections (OR=1.65; 95% CI 0.89 to 3.05). Highly educated adults had lower odds of undetected infection. CONCLUSION: The results indicate an increased risk of SARS-CoV-2 infection in low-educated groups. To promote health equity in the pandemic and beyond, social determinants should be addressed more in infection protection and pandemic planning.

Risky Asset Holdings During Covid-19 and their Distributional Impact: Evidence from Germany.

We present evidence from a repeated survey on risky asset holdings carried out on a representative sample of the German population six times between April and June 2020. Given the size of the Covid-19 shock, we find little evidence of portfolio rebalancing in April 2020. In May, however, individual investors started buying heavily, parallel to market recovery. The cross-section shows large differences as young, educated, high income, and risk tolerant investors are net buyers throughout and, thus, benefit from the stock market recovery. Older individuals, parents of young children, and individuals affected by adverse liquidity shocks from Covid-19 are net sellers. Given the high risk of illness, older people are hit by dual blows to both health and finances.

Competing Reaction Pathways in Heterogeneously Catalyzed Hydrogenation of Allyl Cyanide: The Chemical Nature of Surface Species.

We present a mechanistic study on the formation of an active ligand layer over Pd(111), turning the catalytic surface highly active and selective in partial hydrogenation of an α,ß-unsaturated aldehyde acrolein. Specifically, we investigate the chemical composition of a ligand layer consisting of allyl cyanide deposited on Pd(111) and its dynamic changes under the hydrogenation conditions. On pristine surface, allyl cyanide largely retains its chemical structure and forms a layer of molecular species with the CN bond oriented nearly parallel to the underlying metal. In the presence of hydrogen, the chemical composition of allyl cyanide strongly changes. At 100 K, allyl cyanide transforms to unsaturated imine species, containing the C=C and C=N double bonds. At increasing temperatures, these species undergo two competing reaction pathways. First, the C=C bond become hydrogenated and the stable N-butylimine species are produced. In the competing pathway, the unsaturated imine reacts with hydrogen to fully hydrogenate the imine group and produce butylamine. The latter species are unstable under the hydrogenation reaction conditions and desorb from the surface, while the N-butylimine adsorbates formed in the first reaction pathway remain adsorbed and act as an active ligand layer in selective hydrogenation of acrolein.

Attitudes on voluntary and mandatory vaccination against COVID-19: Evidence from Germany.

Several vaccines against COVID-19 have now been developed and are already being rolled out around the world. The decision whether or not to get vaccinated has so far been left to the individual citizens. However, there are good reasons, both in theory as well as in practice, to believe that the willingness to get vaccinated might not be sufficiently high to achieve herd immunity. A policy of mandatory vaccination could ensure high levels of vaccination coverage, but its legitimacy is doubtful. We investigate the willingness to get vaccinated and the reasons for an acceptance (or rejection) of a policy of mandatory vaccination against COVID-19 in June and July 2020 in Germany based on a representative real time survey, a random sub-sample (SOEP-CoV) of the German Socio-Economic Panel (SOEP). Our results show that about 70 percent of adults in Germany would voluntarily get vaccinated against the coronavirus if a vaccine without side effects was available. About half of residents of Germany are in favor, and half against, a policy of mandatory vaccination. The approval rate for mandatory vaccination is significantly higher among those who would get vaccinated voluntarily (around 60 percent) than among those who would not get vaccinated voluntarily (27 percent). The individual willingness to get vaccinated and acceptance of a policy of mandatory vaccination correlates systematically with socio-demographic and psychological characteristics of the respondents. We conclude that as far as people's declared intentions are concerned, herd immunity could be reached without a policy of mandatory vaccination, but that such a policy might be found acceptable too, were it to become necessary.

Understanding Ligand-Directed Heterogeneous Catalysis: When the Dynamically Changing Nature of the Ligand Layer Controls the Hydrogenation Selectivity.

We present a mechanistic study on the formation and dynamic changes of a ligand-based heterogeneous Pd catalyst for chemoselective hydrogenation of α,ß-unsaturated aldehyde acrolein. Deposition of allyl cyanide as a precursor of a ligand layer renders Pd highly active and close to 100 % selective toward propenol formation by promoting acrolein adsorption in a desired configuration via the C=O end. Employing a combination of real-space microscopic and in-operando spectroscopic surface-sensitive techniques, we show that an ordered active ligand layer is formed under operational conditions, consisting of stable N-butylimine species. In a competing process, unstable amine species evolve on the surface, which desorb in the course of the reaction. Obtained atomistic-level insights into the formation and dynamic evolution of the active ligand layer under operational conditions provide important input required for controlling chemoselectivity by purposeful surface functionalization.

Building External Control Arms From Patient-Level Electronic Health Record Data to Replicate the Randomized IMblaze370 Control Arm in Metastatic Colorectal Cancer.

PURPOSE: External control (EC) arms derived from electronic health records (EHRs) can provide appropriate comparison groups when randomized control arms are not feasible, but have not been explored for metastatic colorectal cancer (mCRC) trials. We constructed EC arms from two patient-level EHR-derived databases and evaluated them against the control arm from a phase III, randomized controlled mCRC trial. METHODS: IMblaze370 evaluated atezolizumab with or without cobimetinib versus regorafenib in patients with mCRC. EC arms were constructed from the Flatiron Health (FH) EHR-derived de-identified database and the combined FH/Foundation Medicine Clinico-Genomic Database (CGDB). IMblaze370 eligibility criteria were applied to the EC cohorts. Propensity scores and standardized mortality ratio weighting were used to balance baseline characteristics between the IMblaze370 and EC arms; balance was assessed using standardized mean differences. Kaplan-Meier method estimated median overall survival (OS). Cox proportional hazards models estimated hazard ratios with bootstrapped 95% CIs to compare differences in OS between study arms. RESULTS: The FH EC included 184 patients; the CGDB EC included 108 patients. Most characteristics were well-balanced (standardized mean difference < 0.1) between each EC arm and the IMblaze370 population. Median OS was similar between the IMblaze370 control arm (8.5 months [95% CI, 6.41 to 10.71]) and both EC arms: FH (8.5 months [6.93 to 9.92]) and CGDB (8.8 months [7.85 to 9.92]). OS comparisons between the IMblaze370 experimental arm and the FH EC (hazard ratio, 0.85 [0.64 to 1.14]) and CGDB EC (0.86 [0.65 to 1.18]) yielded similar results as the comparison with the IMblaze370 control arm (1.01 [0.75 to 1.37]). CONCLUSION: EC arms constructed from the FH database and the CGDB closely replicated the control arm from IMblaze370. EHR-derived EC arms can provide meaningful comparators in mCRC trials when recruiting a randomized control arm is not feasible.

Seroepidemiological study on the spread of SARS-CoV-2 in Germany: Study protocol of the CORONA-MONITORING bundesweit' study (RKI-SOEP study).

The SARS-CoV-2 coronavirus has spread rapidly across Germany. Infections are likely to be under-recorded in the notification data from local health authorities on laboratory-confirmed cases since SARS-CoV-2 infections can proceed with few symptoms and then often remain undetected. Seroepidemiological studies allow the estimation of the proportion in the population that has been infected with SARS-CoV-2 (seroprevalence) as well as the extent of undetected infections. The 'CORONA-MONITORING bundesweit' study (RKI-SOEP study) collects biospecimens and interview data in a nationwide population sample drawn from the German Socio-Economic Panel (SOEP). Participants are sent materials to self-collect a dry blood sample of capillary blood from their finger and a swab sample from their mouth and nose, as well as a questionnaire. The samples returned are tested for SARS-CoV-2 IgG antibodies and SARS-CoV-2 RNA to identify past or present infections. The methods applied enable the identification of SARS-CoV-2 infections, including those that previously went undetected. In addition, by linking the data collected with available SOEP data, the study has the potential to investigate social and health-related differences in infection status. Thus, the study contributes to an improved understanding of the extent of the epidemic in Germany, as well as identification of target groups for infection protection.

Adsorption geometry and self-assembling of chiral modifier (R)-(+)-1-(1-naphthylethylamine) on Pt(111).

A mechanistic study on interaction of a chiral modifier - (R)-(+)-1-(1-naphthylethylamine) (R-NEA) - with a single crystalline Pt(111) surface is reported. The details of the adsorption geometry of individual R-NEA molecules and their intermolecular interactions are addressed by combination of infrared reflection absorption spectroscopy (IRAS) and scanning tunneling microscopy (STM). The spectroscopic observations suggest that the molecules are tilted with respect to the underlying metal substrate with the long axis of the naphthyl ring being parallel and the short axis tilted with respect to the surface. In the medium coverage range, formation of directed 3-5 membered chains was observed by STM for the first time, which points to intermolecular bonding between individual molecules and might account for an unusual tilted adsorption geometry deduced from the IR spectra. Based on the STM images revealing the atomic structure of the Pt grid close to the R-NEA chains, we propose the adsorption configuration of NEA fitting both the IRAS and STM data. The obtained results suggest that this strong intermolecular interaction energetically stabilizes the tilted adsorption geometry of the naphthyl ring, which otherwise would be expected to lie flat on the metal to maximize the dispersive interactions. At the coverage close to saturation, R-NEA builds a self-assembled overlayer with hexagonal symmetry, exhibiting intermolecular distances larger than in the directed chains.

Potential Explanations for Increasing Methylphenidate Use in Children and Adolescents With Attention-Deficit/Hyperactivity Disorder in Germany From 2004 to 2013.

BACKGROUND: Despite a decreasing population of children and adolescents, the cumulative total amount of dispensed methylphenidate (MPH), the first-choice treatment of attention-deficit/hyperactivity disorder (ADHD) in this age group, has increased dramatically in Germany. We investigated potential reasons for this increase such as changes in the ADHD prevalence over time and other potential explanations including the cumulative amount of dispensed MPH per person. METHODS: Based on German claims data, we calculated standardized annual ADHD prevalence rates, proportions of ADHD cases treated with MPH and/or psychotherapy, and mean cumulative defined daily doses of ADHD drugs for 3- to 17-year-old children and adolescents from 2004 to 2013. RESULTS: The ADHD prevalence increased continuously from 2004 to 2011 and remained stable thereafter. In ADHD cases, there was little variation in the proportion of individuals treated with drugs and in the frequency of psychotherapeutic treatment during the whole study period. The annual cumulative mean amount of MPH defined daily doses increased by approximately 30% from 2004 to 2008. CONCLUSIONS: Our analyses suggest that the increase in MPH use in Germany was mainly influenced by an increasing ADHD prevalence and increasing amounts of dispensed MPH per person.

The rich are different: Unravelling the perceived and self-reported personality profiles of high-net-worth individuals.

Beyond money and possessions, how are the rich different from the general population? Drawing on a unique sample of high-net-worth individuals from Germany (≥1 million Euro in financial assets; N = 130), nationally representative data (N = 22,981), and an additional online panel (N = 690), we provide the first direct investigation of the stereotypically perceived and self-reported personality profiles of high-net-worth individuals. Investigating the broad personality traits of the Big Five and the more specific traits of narcissism and locus of control, we find that stereotypes about wealthy people's personality are accurate albeit somewhat exaggerated and that wealthy people can be characterized as stable, flexible, and agentic individuals who are focused more on themselves than on others.

Surface-Driven Keto-Enol Tautomerization: Atomistic Insights into Enol Formation and Stabilization Mechanisms.

Tautomerisation of simple carbonyl compounds to their enol counterparts on metal surfaces is envisaged to enable an easier route for hydrogenation of the C=O bond in heterogeneously catalyzed reactions. To understand the mechanisms of enol formation and stabilization over catalytically active metal surfaces, we performed a mechanistic study on keto-enol tautomerization of a monocarbonyl compound acetophenon over Pt(111) surface. By employing infrared reflection adsorption spectroscopy in combination with scanning tunneling microscopy, we found that enol can be formed by building a ketone-enol dimer, in which one molecule in the enol form is stabilized through hydrogen bonding to the carbonyl group of the second ketone molecule. Based on the investigations of the co-adsorption behavior of acetophenone and hydrogen, we conclude that keto-enol tautomerization occurs in the intramolecular process and does not involve hydrogen transfer through the surface hypothesized previously.

Ultrafast dynamics of UV-excited trans- and cis-ferulic acid in aqueous solutions.

The ultrafast UV-induced processes of the neutral, anionic and dianionic forms of trans- and cis-ferulic acid (FA) in aqueous solution were studied by static and femtosecond time-resolved emission and absorption spectroscopy combined with quantum chemical calculations. In all cases, initial excitation populates the first 1ππ* state. For the dianionic cis-isomer cFA2-, electronic deactivation takes place with a time constant of only 1.4 ps, whereas in all other cases, excited-state deactivation happens more than ten times slower, on a time scale of ≈20 ps. The data suggest sequential de-excitation pathways, where initial sub-picosecond solvent rearrangement and structural changes are followed by internal conversion to an intermediate excited electronic state from which deactivation to the ground state proceeds. Considering the time scales, barrierless excited-state pathways are suggested only in the case of cFA2-, where the observed formation of the isomerisation photoproduct tFA2- provides clear evidence for a cis ⇄ trans isomerisation coordinate. In the other cases, pathways with an excited-state energy barrier, presumably along the same coordinate, are likely, given the longer excited-state lifetimes.