Profiling of oligolignols reveals monolignol coupling conditions in lignifying poplar xylem

Lignin is an aromatic heteropolymer, abundantly present in the walls of secondary thickened cells. Although much research has been devoted to the structure and composition of the polymer to obtain insight into lignin polymerization, the low-molecular weight oligolignol fraction has escaped a detailed characterization. This fraction, in contrast to the rather inaccessible polymer, is a simple and accessible model that reveals details about the coupling of monolignols, an issue that has raised considerable controversy over the past years. We have profiled the methanol-soluble oligolignol fraction of poplar (Populus spp.) xylem, a tissue with extensive lignification. Using liquid chromatography-mass spectrometry, chemical synthesis, and nuclear magnetic resonance, we have elucidated the structures of 38 compounds, most of which were dimers, trimers, and tetramers derived from coniferyl alcohol, sinapyl alcohol, their aldehyde analogs, or vanillin. All structures support the recently challenged random chemical coupling hypothesis for lignin polymerization. Importantly, the structures of two oligomers, each containing a γ-p-hydroxybenzoylated syringyl unit, strongly suggest that sinapyl p-hydroxybenzoate is an authentic precursor for lignin polymerization in poplar

Institutional isomorphism, negativity bias and performance information use by politicians : a survey experiment

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Mortality in non-cystic fibrosis bronchiectasis: A prospective cohort analysis

SummaryIntroductionThere is limited data on mortality and associated morbidity in non-cystic fibrosis bronchiectasis (NCFB). Our aim was to analyze the overall mortality for all newly diagnosed patients from June 2006 onwards and to evaluate risk factors for mortality in this cohort.Methods245 patients who had a new diagnosis of NCFB between June 2006 and October 2012 at the University Hospital of Leuven, Belgium, were included in the analysis. Death was analyzed until end of November 2013. All patients had chest HRCT scan confirming the presence of bronchiectatic lesions and had symptoms of chronic productive cough. Univariate and multivariate Cox proportional hazard survival regression analysis was used to estimate hazard ratios (HR) and their 95% confidence intervals (CI) of variables possibly predicting mortality.ResultsOverall mortality in NCFB patients who had a median follow-up of 5.18 years was 20.4%. Patients with NCFB and associated chronic obstructive pulmonary disease (COPD) had a mortality of 55% in that period. Univariate analysis showed higher mortality according to age, gender, smoking history, Pseudomonas aeruginosa status, spirometry, radiological extent, total number of sputum bacteria and underlying etiology. Multivariate analysis showed significant higher mortality with increasing age (HR = 1.045; p = 0.004), with increasing number of lobes affected (HR = 1.53; p = 0.009) and when patients had COPD associated NCFB (HR = 2.12; p = 0.038). The majority of the 50 deaths were respiratory related (n = 29; 58%).ConclusionNCFB patients with associated COPD disease had the highest mortality rates compared to the other NCFB patients. Additional risk factors for lower survival were increasing age and number of lobes affected

New development: Determinants of financial performance in public organizations

In the slipstream of NPM, public organizations worldwide have had to increase their financial performance by adopting management practices. Nonetheless, financial performance (FP) might be mostly predicted by contingencies that are not within direct managerial control. Drawing on evidence from 308 Flemish municipalities, this article shows that organizational and environmental contingencies affect FP, but a significant amount of variation in FP is unexplained—indicating that management could well matter

Institutional isomorphism, negativity bias and performance information use by politicians: A survey experiment

New Public Management popularized performance measurement in public organizations. Underlying performance measurement's popularity is the assumption that it injects performance information (PI) into decision-making, thus rationalizing the ensuing decisions. Despite its popularity, performance measurement is criticized. In part, this criticism results from the limited knowledge of the conditions under which PI is purposefully used by politicians. We conducted a survey experiment based on real PI with 1,240 politicians. We hypothesized that PI has a positive impact on performance information use (PIU) when PI is benchmarked with coercive, mimetic or normative pressures. Moreover, due to negativity bias we expected this positive impact to be stronger when PI signals low performance. We found that normative pressures had a positive impact on actual PIU while coercive pressures positively affected intended PIU. Negativity bias is only relevant when linked to coercive pressures and intended PIU for analysing the organization's finances

Accurately Determining the Phase Transition Temperature of CsPbI3 via Random-Phase Approximation Calculations and Phase-Transferable Machine Learning Potentials

While metal halide perovskites (MHPs) have shown great potential for various optoelectronic applications, their widespread adoption in commercial photovoltaic cells or photo-sensors is currently restricted, given that MHPs such as CsPbI3 and FAPbI(3) spontaneously transition to an optically inactive non-perovskite phase at ambient conditions. Herein, we put forward an accurate first-principles procedure to obtain fundamental insight into this phase stability conundrum. To this end, we computationally predict the Helmholtz free energy, composed of the electronic ground state energy and thermal corrections, as this is the fundamental quantity describing the phase stability in polymorphic materials. By adopting the random phase approximation method as a wave function-based method that intrinsically accounts for many-body electron correlation effects as a benchmark for the ground state energy, we validate the performance of different exchange-correlation functionals and dispersion methods. The thermal corrections, accessed through the vibrational density of states, are accessed through molecular dynamics simulations, using a phase-transferable machine learning potential to accurately account for the MHPs' anharmonicity and mitigate size effects. The here proposed procedure is critically validated on CsPbI3, which is a challenging material as its phase stability changes slowly with varying temperature. We demonstrate that our procedure is essential to reproduce the experimental transition temperature, as choosing an inadequate functional can easily miss the transition temperature by more than 100 K. These results demonstrate that the here validated methodology is ideally suited to understand how factors such as strain engineering, surface functionalization, or compositional engineering could help to phase-stabilize MHPs for targeted applications

The impact of acute air pollution fluctuations on bronchiectasis pulmonary exacerbation:A case-crossover analysis

In bronchiectasis, exacerbations are believed to be triggered by infectious agents, but often no pathogen can be identified. We hypothesised that acute air pollution exposure may be associated with bronchiectasis exacerbations.We combined a case-crossover design with distributed lag models in an observational record linkage study. Patients were recruited from a specialist bronchiectasis clinic at Ninewells Hospital, Dundee, UK.We recruited 432 patients with clinically confirmed bronchiectasis, as diagnosed by high-resolution computed tomography. After excluding days with missing air pollution data, the final model for particles with a 50% cut-off aerodynamic diameter of 10 µm (PM; 10; ) was based on 6741 exacerbations from 430 patients and for nitrogen dioxide (NO; 2; ) it included 6248 exacerbations from 426 patients. For each 10 µg·m; -; ³ increase in PM; 10; and NO; 2; , the risk of having an exacerbation that same day increased significantly by 4.5% (95% CI 0.9-8.3) and 3.2% (95% CI 0.7-5.8) respectively. The overall (lag zero to four) increase in risk of exacerbation for a 10 μg·m; -3; increase in air pollutant concentration was 11.2% (95% CI 6.0-16.8) for PM; 10; and 4.7% (95% CI 0.1-9.5) for NO; 2; Subanalysis showed higher relative risks during spring (PM; 10; 1.198 (95% CI 1.102-1.303), NO; 2; 1.146 (95% CI 1.035-1.268)) and summer (PM; 10; 2.142 (95% CI 1.785-2.570), NO; 2; 1.352 (95% CI 1.140-1.602)) when outdoor air pollution exposure would be expected to be highest.In conclusion, acute air pollution fluctuations are associated with increased exacerbation risk in bronchiectasis

Gitana: a SQL-based Git Repository Inspector

International audienceSoftware development projects are notoriously complex and difficult to deal with. Several support tools such as issue tracking, code review and Source Control Management (SCM) systems have been introduced in the past decades to ease development activities. While such tools efficiently track the evolution of a given aspect of the project (e.g., bug reports), they provide just a partial view of the project and often lack of advanced querying mechanisms limiting themselves to command line or simple GUI support. This is particularly true for projects that rely on Git, the most popular SCM system today. In this paper, we propose a conceptual schema for Git and an approach that, given a Git repository, exports its data to a relational database in order to (1) promote data integration with other existing SCM tools and (2) enable writing queries on Git data using standard SQL syntax. To ensure efficiency, our approach comes with an incremental propagation mechanism that refreshes the database content with the latest modifications. We have implemented our approach in Gitana, an open-source tool available on GitHub

Multidimensional severity assessment in bronchiectasis:An analysis of 7 European cohorts.

INTRODUCTION: Bronchiectasis is a multidimensional disease associated with substantial morbidity and mortality. Two disease-specific clinical prediction tools have been developed, the Bronchiectasis Severity Index (BSI) and the FACED score, both of which stratify patients into severity risk categories to predict the probability of mortality. METHODS: We aimed to compare the predictive utility of BSI and FACED in assessing clinically relevant disease outcomes across seven European cohorts independent of their original validation studies. RESULTS: The combined cohorts totalled 1612. Pooled analysis showed that both scores had a good discriminatory predictive value for mortality (pooled area under the curve (AUC) 0.76, 95% CI 0.74 to 0.78 for both scores) with the BSI demonstrating a higher sensitivity (65% vs 28%) but lower specificity (70% vs 93%) compared with the FACED score. Calibration analysis suggested that the BSI performed consistently well across all cohorts, while FACED consistently overestimated mortality in 'severe' patients (pooled OR 0.33 (0.23 to 0.48), p<0.0001). The BSI accurately predicted hospitalisations (pooled AUC 0.82, 95% CI 0.78 to 0.84), exacerbations, quality of life (QoL) and respiratory symptoms across all risk categories. FACED had poor discrimination for hospital admissions (pooled AUC 0.65, 95% CI 0.63 to 0.67) with low sensitivity at 16% and did not consistently predict future risk of exacerbations, QoL or respiratory symptoms. No association was observed with FACED and 6 min walk distance (6MWD) or lung function decline. CONCLUSION: The BSI accurately predicts mortality, hospital admissions, exacerbations, QoL, respiratory symptoms, 6MWD and lung function decline in bronchiectasis, providing a clinically relevant evaluation of disease severity