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Mg-doped VO2 thin films with thermochromic properties were made by reactive DC magnetron co-sputtering onto heated substrates, and spectral absorption was recorded at room temperature in the 0.5 < ħω < 3.5 eV energy range. Clear evidence was found for a widening of the main band gap from 1.67 to 2.32 eV as the Mg/(V + Mg) atomic ratio went from zero to 0.19, thereby significantly lowering the luminous absorption. This technologically important effect could be reconciled with spin-polarized density functional theory calculations using the Heyd-Scuseria-Ernzerhof [Heyd et al., J. Chem. Phys. 118, 8207 (2003); ibid. 124, 219906 (2006)] hybrid functional. Specifically, the calculated luminous absorptance decreased when the Mg/(V + Mg) ratio was increased from 0.125 to 0.250. [ABSTRACT FROM AUTHOR]

We propose a resolution to the puzzle presented by the surface defects observed with STM at the (111) surface facet of CeO2 single crystals. In the seminal paper of Esch et al. [Science 309, 752 (2005)1 they were identified with oxygen vacancies, but the observed behavior of these defects is inconsistent with the results of density functional theory (DFT) studies of oxygen vacancies in the literature. We resolve these inconsistencies via DFT calculations of the properties of both oxygen vacancies and fluorine impurities at CeO2 (111), the latter having recently been shown to exist in high concentrations in single crystals from a widely used commercial source of such samples. We find that the simulated filled-state STM images of surface-layer oxygen vacancies and fluorine impurities are essentially identical, which would render problematic their experimental distinction by such images alone. However, we find that our theoretical results for the most stable location, mobility, and tendency to cluster, of fluorine impurities are consistent with experimental observations, in contrast to those for oxygen vacancies. Based on these results, we propose that the surface defects observed in STM experiments on CeO2 single crystals reported heretofore were not oxygen vacancies, but fluorine impurities. Since the similarity of the simulated STM images of the two defects is due primarily to the relative energies of the 2p states of oxygen and fluorine ions, this confusion might also occur for other oxides which have been either doped or contaminated with fluorine. [ABSTRACT FROM AUTHOR]

It is known that, in the proximity of a neutral wall, liquids experience diffusion enhancement relative to their bulk diffusion, but the origin of this phenomenon is still unknown. We report a molecular dynamics simulation investigating the dynamics of a simple liquid in the proximity to a non-interacting smooth confining wall, which exhibits a strong diffusion enhancement within the liquid layers adjacent to the wall. We present an analysis of these results, demonstrating that the observed diffusion enhancement can be accounted for, with numerical accuracy, using the universal scaling law that relates the liquid diffusion rate to the excess entropy. These results show that the scaling law, which has so far only been used for the description of the bulk liquid diffusion, can be successfully used to describe the diffusion in liquids under nano-scale confinement., (© 2024 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International (CC BY-NC-ND) license (https://creativecommons.org/licenses/by-nc-nd/4.0/).)

High-accuracy molecular force field models suited for hot gases and plasmas are not as abundant as those geared toward ambient pressure and temperature conditions. Here, we present an improved version of our previous electron-density based force field model that can now account for polarization effects by adjusting the atomic valence electron contributions to match ab initio calculated Mulliken partial charges. Using a slightly modified version of the Hohenberg-Kohn theorem, we also include an improved theoretical formulation of our model when applied to systems with degenerate ground states. We present two variants of our polarizable model, fitted from ab initio reference data calculated at CCSD(T)/cc-pVTZ and CCSD(T)/CEP-31G levels of theory, that both accurately model water dimer interaction energies. Further improvements include the additional interaction components with fictitious non-spherically symmetric, yet atom-centered, electron densities and fitting the exchange and correlation coefficients against analytical expressions. The latter removes all unphysical oscillations that are observed in the previous non-polarizable variant of our force field., (© 2024 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution-NonCommercial 4.0 International (CC BY-NC) license (https://creativecommons.org/licenses/by-nc/4.0/).)

We report here an experimental-computational study of hydrated TiO 2 anatase nanoparticles interacting with glycine, where we obtain quantitative agreement of the measured adsorption free energies. Ab initio simulations are performed within the tight binding and density functional theory in combination with enhanced free-energy sampling techniques, which exploit the thermodynamic integration of the unbiased mean forces collected on-the-fly along the molecular dynamics trajectories. The experiments adopt a new and efficient setup for electrochemical impedance spectroscopy measurements based on portable screen-printed gold electrodes, which allows fast and in situ signal assessment. The measured adsorption free energy is -30 kJ/mol (both from experiment and calculation), with preferential interaction of the charged NH 3 + group which strongly adsorbs on the TiO 2 bridging oxygens. This highlights the importance of the terminal amino groups in the adsorption mechanism of amino acids on hydrated metal oxides. The excellent agreement between computation and experiment for this amino acid opens the doors to the exploration of the interaction free energies for other moderately complex bionano systems.

Background: To assess whether retrograde cerebral perfusion reduces neurological injury and mortality in patients undergoing surgery for acute type A aortic dissection., Methods: Single-center, retrospective, observational study including all patients undergoing acute type A aortic dissection repair with deep hypothermic circulatory arrest between January 1998 and December 2022 with or without the adjunct of retrograde cerebral perfusion. 515 patients were included: 257 patients with hypothermic circulatory arrest only and 258 patients with hypothermic circulatory arrest and retrograde cerebral perfusion. The primary endpoints were clinical neurological injury, embolic lesions, and watershed lesions. Multivariable logistic regression was performed to identify independent predictors of the primary outcomes. Survival analysis was performed using Kaplan-Meier estimates., Results: Clinical neurological injury and embolic lesions were less frequent in patients with retrograde cerebral perfusion (20.2% vs. 28.4%, p = 0.041 and 13.7% vs. 23.4%, p = 0.010, respectively), but there was no significant difference in the occurrence of watershed lesions (3.0% vs. 6.1%, p = 0.156). However, after multivariable logistic regression, retrograde cerebral perfusion was associated with a significant reduction of clinical neurological injury (OR: 0.60; 95% CI 0.36-0.995, p = 0.049), embolic lesions (OR: 0.55; 95% CI 0.31-0.97, p = 0.041), and watershed lesions (OR: 0.25; 95%CI 0.07-0.80, p = 0.027). There was no significant difference in 30-day mortality (12.8% vs. 11.7%, p = ns) or long-term survival between groups., Conclusion: In this study, we showed that the addition of retrograde cerebral perfusion during hypothermic circulatory arrest in the setting of acute type A aortic dissection repair reduced the risk of clinical neurological injury, embolic lesions, and watershed lesions., (© 2024. The Author(s).)

In high-energy molecular dynamics or Monte Carlo simulations, standard force fields optimized for simulations at ambient temperatures are inadequate. This is largely because their repulsive parts have been regarded as not very significant, even well below zero interaction energies. It is, therefore, not obvious which force fields to resort to for simulating hot gases or plasmas. A force field model that uses the electronic densities of noninteracting atoms or molecules within the pair approximation is introduced. We start by deriving a naïve model that neglects any exchange and correlation effects between the electronic clouds and then correct this model by adding a term calibrated from ab initio calculations using the CCSD(T)/cc-pVTZ level of theory. The resulting expression for this term can be regarded as a simple exchange-correlation function. We compare the results for the repulsive part of the potential energy hypersurfaces with the force fields commonly used on some dimers of small molecules.

Objectives: It has been commonly accepted that untreated acute type A aortic dissection (ATAAD) results in an hourly mortality rate of 1-2% during the 1st 24 h after symptom onset. The data to support this statement rely solely on patients who have been denied surgical treatment after reaching surgical centres. The objective was to perform a total review of non-surgically treated (NST) ATAAD and provide contemporary mortality data., Methods: This was a regional, retrospective, observational study. All patients receiving one of the following diagnoses: International Classification of Diseases (ICD)-9 4410, 4411, 4415, 4416 or ICD-10 I710, I711, I715, I718 in an area of 1.9 million inhabitants in Southern Sweden during a period of 23 years (January 1998 to November 2021) were retrospectively screened. The search was conducted using all available medical registries so that every patient diagnosed with ATAAD in our region was identified. The charts and imaging of each screened patient were subsequently reviewed to confirm or discard the diagnosis of ATAAD., Results: Screening identified 2325 patients, of whom 184 NST ATAAD patients were included. The mortality of NST ATAAD was 47.3 ± 4.4%, 55.0 ± 4.4%, 76.7 ± 3.7% and 83.9 ± 4.3% at 24 h, 48 h, 14 days and 1 year, respectively. The hourly mortality rate during the 1st 24 h after symptom onset was 2.6%., Conclusions: This study observed higher mortality than has previously been reported. It emphasizes the need for timely diagnosis, swift management and emergent surgical treatment for patients suffering an acute type A aortic dissection., (© The Author(s) 2024. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery.)

Optimizing a target function over the space of organic molecules is an important problem appearing in many fields of applied science but also a very difficult one due to the vast number of possible molecular systems. We propose an evolutionary Monte Carlo algorithm for solving such problems which is capable of straightforwardly tuning both exploration and exploitation characteristics of an optimization procedure while retaining favorable properties of genetic algorithms. The method, dubbed MOSAiCS ( M etropolis O ptimization by S ampling A daptively i n C hemical S pace), is tested on problems related to optimizing components of battery electrolytes, namely, minimizing solvation energy in water or maximizing dipole moment while enforcing a lower bound on the HOMO-LUMO gap; optimization was carried out over sets of molecular graphs inspired by QM9 and Electrolyte Genome Project (EGP) data sets. MOSAiCS reliably generated molecular candidates with good target quantity values, which were in most cases better than the ones found in QM9 or EGP. While the optimization results presented in this work sometimes required up to 10 6 QM calculations and were thus feasible only thanks to computationally efficient ab initio approximations of properties of interest, we discuss possible strategies for accelerating MOSAiCS using machine learning approaches.

The H2O and H2O2 molecules resemble each other in a multitude of ways as has been noted in the literature. Here, we present density functional theory (DFT) calculations for the H2O2(s) and H2O2·2H2O(s) crystals and make selected comparisons with ice polymorphs. The performance of a number of dispersion-corrected density functionals-both self-consistent and a posteriori ones-are assessed, and we give special attention to the D3 correction and its effects. The D3 correction to the lattice energies is large: for H2O2(s) the D3 correction constitutes about 25% of the lattice energy using PBE, much more for RPBE, much less for SCAN, and it primarily arises from non-H-bonded interactions out to about 5 Å.The large D3 corrections to the lattice energies are likely a consequence of several effects: correction for missing dispersion interaction, the ability of D3 to capture and correct various other kinds of limitations built into the underlying DFT functionals, and finally some degree of cell-contraction-induced polarization enhancement. We find that the overall best-performing functionals of the twelve examined are optPBEvdW and RPBE-D3. Comparisons with DFT assessments for ices in the literature show that where the same methods have been used, the assessments largely agree., (© 2023 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/).)

The nature of the hydrophobicity found in rare-earth oxides is intriguing. The CeO 2 (100) surface, despite its strongly hydrophilic nature, exhibits hydrophobic behaviour when immersed in water. In order to understand this puzzling and counter-intuitive effect we performed a detailed analysis of the confined water structure and dynamics. We report here an ab-initio molecular dynamics simulation (AIMD) study which demonstrates that the first adsorbed water layer, in immediate contact with the hydroxylated CeO 2 surface, generates a hydrophobic interface with respect to the rest of the liquid water. The hydrophobicity is manifested in several ways: a considerable diffusion enhancement of the confined liquid water as compared with bulk water at the same thermodynamic condition, a weak adhesion energy and few H-bonds above the hydrophobic water layer, which may also sustain a water droplet. These findings introduce a new concept in water/rare-earth oxide interfaces: hydrophobicity mediated by specific water patterns on a hydrophilic surface., (© 2023 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

Theoretical and experimental vibrational signatures of H2O and OH- (dissociated water) adsorbed on stoichiometric ceria{111} surfaces are compared. The experimental ones were collected from low-coverage experiments in the literature, and the theoretical anharmonic frequencies were generated using density functional theory calculations employing the optPBE-vdW functional for coverages from 0.5 to a few monolayers. It is found that (i) the experiments and our calculations overall agree well, lending credibility to both; (ii) the calculations manage to resolve the large class of H-bonded motifs into frequency classes that can guide experimental assignments; (iii) it is possible to find a geometrical H-bond definition that also captures the OH vibrational frequency downshifts well: R(H⋯O) ≤2.5 Å and the O-H⋯O angle θ ≥ 100°; and (iv) the frequency vs electric field relations for water and hydroxides (i.e., dissociated water) follow different and well-separated curves., (© 2023 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/).)

Objective: The study objective was to assess the radiological properties of acute type A aortic dissection-related neurological injuries and identify predictors of neurological injury., Methods: Our single-center, retrospective, observational study included all patients who underwent acute type A aortic dissection repair between January 1998 and December 2021. Multivariable analyses and Cox regression were performed to identify predictors of embolic lesions, watershed lesions, neurological injury, 30-day mortality, and late mortality., Results: A total of 538 patients were included. Of these, 120 patients (22.3%) experienced postoperative neurological injury; 74 patients (13.8%) had postoperative stroke, and 36 patients (6.8%) had postoperative coma. The 30-day mortality was 22.7% in the neurological injury group versus 5.8% in the no neurological injury group ( P  < .001). We identified several independent predictors of neurological injury. Cerebral malperfusion (odds ratio, 2.77; 95% confidence interval, 1.53-5.00), systemic hypotensive shock (odds ratio, 1.97; 95% confidence interval, 1.13-3.43), and aortic arch replacement (odds ratio, 3.08; 95% confidence interval, 1.17-8.08) predicted embolic lesions. Diabetes mellitus (odds ratio, 5.35; 95% confidence interval, 1.85-15.42), previous cardiac surgery (odds ratio, 8.62; 95% confidence interval, 1.47-50.43), duration of hypothermic circulatory arrest (odds ratio, 1.05; 95% confidence interval, 1.01-1.08), cardiopulmonary bypass time (odds ratio, 1.01; 95% confidence interval, 1.00-1.01), ascending aortic/arch cannulation (odds ratio, 5.68; 95% confidence interval, 1.88-17.12), and left ventricular cannulation (odds ratio, 17.81; 95% confidence interval, 1.69-188.01) predicted watershed lesions. Retrograde cerebral perfusion (odds ratio, 0.28; 95% confidence interval, 0.01-0.84) had a protective effect against watershed lesions., Conclusions: In this study, we demonstrated that the radiological features of neurological injury may be as important as clinical characteristics in understanding the pathophysiology and causality behind neurological injury related to acute type A aortic dissection repair., (© 2023 The Author(s).)

Introduction: Neurological complications after surgery for acute type A aortic dissection (ATAAD) increase patient morbidity and mortality. Carbon dioxide flooding is commonly used in open-heart surgery to reduce the risk of air embolism and neurological impairment, but it has not been evaluated in the setting of ATAAD surgery. This report describes the objectives and design of the CARTA trial, investigating whether carbon dioxide flooding reduces neurological injury following surgery for ATAAD., Methods and Analysis: The CARTA trial is a single-centre, prospective, randomised, blinded, controlled clinical trial of ATAAD surgery with carbon dioxide flooding of the surgical field. Eighty consecutive patients undergoing repair of ATAAD, and who do not have previous neurological injuries or ongoing neurological symptoms, will be randomised (1:1) to either receive carbon dioxide flooding of the surgical field or not. Routine repair will be performed regardless of the intervention. The primary endpoints are size and number of ischaemic lesions on brain MRI performed after surgery. Secondary endpoints are clinical neurological deficit according to the National Institutes of Health Stroke Scale, level of consciousness using the Glasgow Coma Scale motor score, brain injury markers in blood after surgery, neurological function according to the modified Rankin Scale and postoperative recovery 3 months after surgery., Ethics and Dissemination: Ethical approval has been granted by Swedish Ethical Review Agency for this study. Results will be disseminated through peer-reviewed media., Trial Registration Number: NCT04962646., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2023. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

A computational protocol is developed for efficient studies of partially reduced redox-active oxides using the self-consistent charge density functional tight-binding method. The protocol is demonstrated for ceria, which is a prototypical reducible oxide material. The underlying idea is to achieve a consistent (and harmonized) set of Slater-Koster (SK) tables with connected repulsive potentials that enable switching on and off the in-valence description of the Ce 4f states without serious loss of accuracy in structure and energetics. The implicit treatment of the Ce 4f states, with the use of f-in-core SK-tables, is found to lead to a significant decrease in computational time. More importantly, it allows for explicit control of the oxidation states of individual Ce atoms. This makes it possible to "freeze" the electronic configuration, thereby allowing the exploration of the energetics for various meta-stable configurations. We anticipate that the outlined strategy can help to shed light on the interplay between the size, shape, and redox activity for nanoceria and other related materials.

Background: Neurological injuries are frequent following Acute Type A Aortic Dissection (ATAAD) repair occurring in 4-30% of all patients. Our objective was to study whether S100B can predict neurological injury following ATAAD repair., Methods: This was a single-center, retrospective, observational study. The study included all patients that underwent ATAAD repair at our institution between Jan 1998 and Dec 2021 and had recorded S100B-values. The primary outcome measure was neurological injury, defined as focal neurological deficit or coma diagnosed by clinical assessment with or without radiological confirmation and with a symptom duration of more than 24 h. Secondary outcome measure was 30-day mortality., Results: 538 patients underwent surgery during the study period and 393 patients, had recorded S100B-values. The patients had a mean age of 64.4 ± 11.1 years and 34% were female. Receiver operating characteristic curve for S100B 24 h postoperatively yielded area under the curve 0.687 (95% CI 0.615-0.759) and best Youden's index corresponded to S100B 0.225 which gave a sensitivity of 60% and specificity of 75%. Multivariable logistic regression identified S100B ≥ 0.23 μg/l at 24 h as an independent predictor for neurological injury (OR 4.71, 95% CI 2.59-8.57; p < 0.01) along with preoperative cerebral malperfusion (OR 4.23, 95% CI 2.03-8.84; p < 0.01) as well as an independent predictor for 30-day mortality (OR 4.57, 95% CI 1.18-11.70; p < 0.01)., Conclusions: We demonstrated that S100B, 24 h after surgery is a strong independent predictor for neurological injury and 30-day mortality after ATAAD repair., Trial Registration: As this was a retrospective observational study it was not registered., (© 2023. The Author(s).)

Robust correlation curves are essential to decipher structural information from IR-vibrational spectra. However, for surface-adsorbed water and hydroxides, few such correlations have been presented in the literature. In this paper, OH vibrational frequencies are correlated against 12 structural descriptors representing the quantum mechanical or geometrical environment, focusing on those external to the vibrating molecule. A nonbiased fitting procedure based on Gaussian process regression (GPR) was used alongside simple analytical functional forms. The training data consist of 217 structurally unique OH groups from 38 water/metal oxide interface systems for MgO, CaO and CeO 2 , all optimized at the DFT level, and the fully anharmonic and uncoupled OH vibrational signatures were calculated. Among our results, we find the following: (i) The intermolecular R (H···O) hydrogen bond distance is particularly strong, indicating the primary cause of the frequency shift. (ii) Similarly, the electric field along the H-bond vector is also a good descriptor. (iii) Highly detailed machine learning descriptors (ACSF, SOAP) are less intuitive but were found to be more capable descriptors. (iv) Combinations of geometric and QM descriptors give the best predictions, supplying complementary information.

The CO 2 molecule is weakly bound in water. Here we analyze the influence of a dissolved CO 2 molecule on the structure and OH vibrational spectra of the surrounding water. From the analysis of ab initio molecular dynamics simulations (BLYP-D3) we present static (structure, coordination, H-bonding, tetrahedrality) and dynamical (OH vibrational spectra) properties of the water molecules as a function of distance from the solute. We find a weakly oscillatory variation ("ABBA") in the 'solution minus bulk water' spectrum. The origin of these features can largely be traced back to solvent-solute hard-core interactions which lead to variations in density and tetrahedrality when moving from the solute's vicinity out to the bulk region. The high-frequency peak in the solute-affected spectra is specifically analyzed and found to originate from both water OH groups that fulfill the geometric H-bond criteria, and from those that do not (dangling ones). Effectively, neither is hydrogen-bonded.

Background: Doppler ultrasound can diagnose testicular torsion with high sensitivity and specificity but may delay surgical treatment. This study aims to assess whether the use of doppler ultrasound, in cases with intermediate clinical suspicion of testicular torsion, can improve diagnostic accuracy compared to clinical assessment alone., Methods: We implemented a new clinical algorithm where patients with intermediate suspicion of testicular torsion undergo doppler ultrasound within 60 min. This study compared the patients that presented within one year prior to the implementation (group 1) to the patients who presented within one year after the implementation (group 2). The primary outcome measure was failure to confirm testicular torsion upon surgical exploration (negative surgical exploration). Missed testicular torsion was one of the secondary endpoints., Results: 590 consecutive patients were included. 322 (55%) in group 1 and 268 (45%) in group 2. There were 9 (2.8%) testicular torsions in group 1 vs 9 (3.4%) in group 2 ( p  = 0.69) and 2 (0.6%) missed testicular torsions in group 1 vs 0 in group 2 ( p  = 0.50). Doppler ultrasound was performed in 65 patients (24.2%) in group 2 vs 0 in group 1 ( p  < 0.01). Negative surgical exploration was performed in 27 (8.4%) patients in group 1 vs 8 (3.0%) in group 2 ( p  < 0.01)., Conclusion: Doppler ultrasound assessment of patients at intermediate clinical risk of testicular torsion significantly reduced the frequency of negative surgical explorations without increased rate of missed testicular torsions.

Corrosion occurring in reinforced concrete has turned into a primary concern of the current century, concrete being the most ubiquitous and predominant material used in the construction industry. Among the many interrelated processes that trigger corrosion of metallic reinforcements, the penetration of chloride ions into the concrete matrix is the most insidious threat. Herein, we developed the first electrochemical device entirely made of paper that allows for the direct, prompt, and noninvasive evaluation of free chloride ion contamination in concrete-based constructions. Our device is based on a three-layer wax-modified filter paper, consisting of two Ag/AgCl screen-printed electrodes that are interfaced by a junction pad in a sandwich-like configuration. Filter paper allows for generating a vertical-flow potentiometric device capable of measuring the electrochemical potential between two solutions containing different concentrations of chloride ions, which are separately drop-cast on the top and bottom layers. After demonstrating the analytical performance of the device, the same principle was applied to the evaluation of the chloride contents in different concrete samples, exploiting paper as a suitable interfacing material for potentiometric measurements on the cement solid surface. Laboratory-prepared concrete samples with known chloride contents were first assessed, and then, the paper-based vertical-flow device was applied to real concrete structures at the Giacomo Manzù Museum (Ardea, Italy) for the evaluation of chloride contamination caused by the proximity to the seaside. The capability of our device to provide timely warning of the risk conditions of concrete-based artifacts was demonstrated.

We study substitutional fluorine, chlorine and bromine impurities at CeO 2 (111), and their effects on the oxygen chemistry of the surface, using density functional theory. We find that impurity formation results in a halide ion and one Ce 3+ ion for all three halogens, although the formation energy depends strongly on the identity of the halogen; however, once formed, all three halogens exhibit a similar propensity to form impurity-impurity pairs. Furthermore, while the effects of halogen impurities on oxygen vacancy formation are marginal, they are more significant for oxygen molecule adsorption, due to electron transfer from the Ce 3+ ion which results in an adsorbed superoxide molecule. We also consider the displacement of a halide ion on to the surface by half of an oxygen molecule, and find that the energy required to do so depends strongly not only on the identity of the halogen, but also on whether or not a second halogen impurity, with its associated Ce 3+ ion, is present; if it is, then the process is greatly facilitated. Overall, our results demonstrate the existence of a rich variety of ways in which the oxygen chemistry of CeO 2 (111) may be modified by the presence of halogen dopants.

Background: To reduce local recurrence risk, rectal washout (RW) is integrated in the total mesorectal excision (TME) technique when performing anterior resection (AR) for rectal cancer. Although RW is considered a safe practice, data on the complication risk are scarce. Our aim was to examine the association between RW and 30-day postoperative complications after AR for rectal cancer., Methods: Patients from the Swedish Colorectal Cancer Registry who underwent AR between 2007 and 2013 were analysed using multivariable methods., Results: A total of 4821 patients were included (4317 RW, 504 no RW). The RW group had lower rates of overall complications (1578/4317 (37%) vs. 208/504 (41%), p = 0.039), surgical complications (879/4317 (20%) vs. 140/504 (28%), p < 0.001) and 30-day mortality (50/4317 (1.2%) vs. 12/504 (2.4%), p = 0.020). In multivariable analysis, RW was a risk factor neither for overall complications (OR 0.73, 95% CI 0.60-0.90, p = 0.002) nor for surgical complications (OR 0.62, 95% CI 0.50-0.78, p < 0.001)., Conclusions: RW is a safe technique that does not increase the 30-day postoperative complication risk after AR with TME technique for rectal cancer.

We report an ab initio molecular dynamics (MD) simulation investigating the effect of a fully hydrated surface of TiO 2 on the water dynamics. It is found that the universal relation between the rotational and translational diffusion characteristics of bulk water is broken in the water layers near the surface with the rotational diffusion demonstrating progressive retardation relative to the translational diffusion when approaching the surface. This kind of rotation-translation decoupling has so far only been observed in the supercooled liquids approaching glass transition, and its observation in water at a normal liquid temperature is of conceptual interest. This finding is also of interest for the application-significant studies of the water interaction with fully hydrated nanoparticles. We note that this is the first observation of rotation-translation decoupling in an ab initio MD simulation of water.

It has been suggested in the literature that keto-to-enol tautomerization plays a vital role for lignin fragmentation under mild conditions. On the other hand, previous modelling has shown that the adsorbed keto form is more stable than enol on the Pd(111) catalyst. The current density functional theory study of lignin model molecules shows that, in the gas-phase, keto is more stable than enol, but on the Pd surface, we find enol conformers that are at least as stable as keto. This supports the experimental result that the favourable reaction pathway for lignin depolymerization involves keto-enol tautomerization. An energy decomposition analysis gives insights concerning the origin of the fine energy balance between the keto and enol forms, where the molecule-surface interaction (-7 eV) and the molecular strain energy (+3 eV) are the main contributors to the adsorption energy., (© 2020 The Authors. Published by Wiley-VCH GmbH.)

The rational design of ideal catalysts for the oxygen reduction reaction (ORR) is of great significance for solving the electrocatalytic potential problems in proton exchange membrane fuel cells (PEMFCs). Pt n (n = 1-4) and Pt 3 Au alloy subnanoclusters supported on a defective Ti 2 CO 2 monolayer with oxygen vacancies (denoted as v-Ti 2 CO 2 ) are simulated by using density functional theory to investigate their ORR performance. The geometries, energetics, and electronic properties of the different systems are analyzed. It is found that the supported Pt 3 Au alloy subnanocluster possesses the best ORR activity. The underlying mechanisms of the improved ORR activity originates from the moderate hybridization between the O 2p and the 5d orbitals of Au and Pt according to the density of states analysis. Our study suggests a facile route for designing low-cost MXene-based electrocatalysts by alloying transition metals with Pt catalysts, which may stimulate realization of suitable alternative catalysts for ORR catalysis.

Alkaline electrolyte solutions are important components in rechargeable batteries and alkaline fuel cells. As the ionic conductivity is thought to be a limiting factor in the performance of these devices, which are often operated at elevated temperatures, its temperature dependence is of significant interest. Here we use NaOH as a prototypical example of alkaline electrolytes, and for this system we have carried out reactive molecular dynamics simulations with an experimentally verified high-dimensional neural network potential derived from density-functional theory calculations. It is found that in concentrated NaOH solutions elevated temperatures enhance both the contributions of proton transfer to the ionic conductivity and deviations from the Nernst-Einstein relation. These findings are expected to be of practical relevance for electrochemical devices based on alkaline electrolyte solutions.