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Considering porous materials as host matrices is an elegant way to enable photoswitching of non-covalently attached organic dyes even in the solid state. By focusing on the resulting optical properties as a function of loading degree and synthesis procedure, the occurring host–guest and guest–guest interactions can be determined and further exploited. In the course of this study, the photochromic behavior of ortho-tetrafluoroazobenzene (tF-AZB) inside flexible DMOF-1 was investigated from these points of view. It was found that depending on the loading degree and temperature, tF-AZB shows varying E/Z ratios and switching efficiency. For systems with low loading, reversible visible light induced isomerization was observed over ten switching cycles: Upon violet light exposure, formation of 100% E isomer was generated, while green light irradiation resulted in ∼60% Z-tF-AZB. Complementary molecular dynamics simulations at DFTB (density functional tight binding)-level revealed changing binding sites for Z-tF-AZB inside DMOF-1. For the E isomer, only low oscillations have been found, which in turn display a rare T-stacking interaction. Although the interaction strengths of the E and Z isomers with DMOF-1 are in the same range, the different mobility of both isomers due to varying binding sites explains the preference of the E isomer even upon green light exposure.

To the best of our knowledge, this is the first molecular dynamics simulation study on the dimeric form of the LuxS enzyme from Vibrio cholerae to evaluate its structural and dynamical properties including the dynamics of the interface formed by the two monomeric chains of the enzyme. The dynamics of the interfacial region were investigated in terms of inter-residual contacts and the associated interface area of the enzyme in its ligand-free and ligand–bound states which produced characteristics contrast in the interfacial dynamics. Moreover, the binding patterns of the two inhibitors (RHC and KRI) to the enzyme forming two different enzyme–ligand complexes were analyzed which pointed towards a varying inhibition potential of the inhibitors as also revealed by the free energies of ligand binding. It is shown that KRI is a more potent inhibitor than RHC – a substrate analogue, showing correlation with experimental data. Moreover, the role of a loop in chain B of the enzyme was found to facilitate the binding of RHC similar to that of the substrate, while KRI demonstrates a differing binding pattern. The computation of the free energy of binding for the two ligands was also carried out via thermodynamic integration which ultimately served to correlate the dynamical properties with the inhibition potential of two different ligands against the enzyme. Furthermore, this successful study provides a rational to suggest novel LuxS inhibitors which could become promising candidates to treat the diseases caused by a broad variety of bacterial species.

For more than half a century computer simulations were developed and employed to study ensemble properties of a wide variety of atomic and molecular systems with tremendous success. Nowadays, a selection of force-fields is available that describe the interactions in such systems. A key feature of force-fields is an adequate description of the electrostatic potential (ESP). Several force-fields model the ESP via point charges positioned at the atom centers. A major shortcoming of this approach, its inability to model anisotropies in the ESP, can be mitigated using additional charge sites. It has been shown that nitrogen is the most problematic element abundant in many polymers as well as large molecules of biological origin. To tackle this issue, small organic molecules containing a single nitrogen atom were studied. In performing rigorous scans of the surroundings of these nitrogen atoms, positions where a single extra charge can enhance the ESP description the most were identified. Significant improvements are found for ammonia, amines, and amides. Interestingly, the optimal location for the extra charge does not correlate with the chemically intuitive position of the nitrogen lone pair. In fact, the placement of an extra charge in the lone-pair location does not lead to significant improvements in most cases.

Nonselective beta-blockers are used as prophylaxis for variceal bleeding in patients with advanced chronic liver disease (ACLD). The acute hemodynamic response to intravenous propranolol (i.e., ≥10% reduction in hepatic venous pressure gradient [HVPG]) is linked to a decreased risk of variceal bleeding. In this study, we aimed to investigate the overall prognostic value of an acute response in compensated and decompensated ACLD. We analyzed the long-term outcome of prospectively recruited patients with ACLD following a baseline HVPG measurement with an intraprocedural assessment of the acute hemodynamic response to propranolol. Overall, we included 98 patients with ACLD (mean ± SD age, 56.4 ± 11.5 years; 72.4% decompensated; 88.8% varices; mean ± SD HVPG, 19.9 ± 4.4 mm Hg) who were followed for a median of 9.6 (interquartile range, 6.5-18.2) months. Fifty-seven patients (58.2%) demonstrated an acute hemodynamic response to propranolol that was associated with a decreased risk of variceal bleeding (at 12 months, 3.6% vs. 15% in nonresponder; log-rank, p = 0.038) and hepatic decompensation (at 12 months, 23% vs. 33% in nonresponder; log-rank, p = 0.096). On multivariate analysis, the acute response was an independent predictor of first/further hepatic decompensation (adjusted hazards ratio, 0.31; 95% confidence interval [CI], 0.13-0.70; p = 0.005). Importantly, there was a tendency toward a prolonged transplant-free survival in acute responders compared to nonresponders (34.2; 95% CI, 29.2-39.2 vs. 25.2; 95% CI, 19.8-30.6 months; log-rank, p = 0.191). Conclusions: Patients with ACLD who achieve an acute hemodynamic response to intravenous propranolol experience a lower risk of variceal bleeding and nonbleeding hepatic decompensation events compared to nonresponders. An assessment of the acute hemodynamic response to intravenous propranolol provides important prognostic information in ACLD.

Controlling the switching efficiency of photoactive hybrid systems is an obligatory key prerequisite for systematically improving the design of functional materials. By modulating the degree of fluorination and the amount being embedded into porous hosts, the

BackgroundCongestion and plasma volume expansion are important features of heart failure, whose prognostic significance has been investigated in a range of surgical and non-surgical settings. The aim of this study was to evaluate the value of the estimated plasma volume status (ePVS) in patients undergoing isolated tricuspid valve surgery.MethodsThis study included patients who underwent isolated tricuspid valve surgery at the Vienna General Hospital (Austria) between July 2008 and November 2018. The PVS cut-off was calculated using ROC analysis and Youden's Index.ResultsEighty eight patients (median age: 58 [IQR: 35-70] years; 44.3% male; 75.6% NYHA III/IV; median EuroSCORE II 2.65 [IQR: 1.70-5.10]; 33.0% endocarditis-related regurgitation; 60.2% isolated repair; 39.8% isolated replacement) were included in this study. Patients who died within 1 year following surgery had significantly higher baseline ePVS values than survivors (median ePVS 5.29 [IQR: −1.55-13.55] vs. −3.68 [IQR: −10.92-4.22]; p = 0.005). During a median actuarial follow-up of 3.02 (IQR: 0.36-6.80) years, patients with a preoperative ePVS ≥ −4.17 had a significantly increased mortality (log-rank p = 0.006).ConclusionsePVS is an easily obtainable risk parameter for patients undergoing isolated tricuspid valve surgery capable of predicting mid- and long-term outcomes after isolated tricuspid valve surgery.

Introduction: Manuscripts that have successfully used machine learning (ML) to predict a variety of perioperative outcomes often use only a limited number of features selected by a clinician. We hypothesized that techniques leveraging a broad set of features for patient laboratory results, medications, and the surgical procedure name would improve performance as compared to a more limited set of features chosen by clinicians. Methods Feature vectors for laboratory results included 702 features total derived from 39 laboratory tests, medications consisted of a binary flag for 126 commonly used medications, procedure name used the Word2Vec package for create a vector of length 100. Nine models were trained: Baseline Features, one for each of the three types of data Baseline+Each data type (, all features, and then all features with feature reduction algorithm. Results Across both outcomes the models that contained all features (model 8) (Mortality ROC-AUC 94.42, PR-AUC 31.0; AKI ROC-AUC 92.47, PR-AUC 76.73) was superior to models with only subsets of features Conclusion Featurization techniques leveraging a broad away of clinical data can improve performance of perioperative prediction models.

The purpose of this review is to demonstrate advances, challenges and perspectives of quantum chemical approaches in molecular spectroscopy of the condensed phase. Molecular spectroscopy, particularly vibrational spectroscopy and electronic spectroscopy, has been used extensively for a wide range of areas of chemical sciences and materials science as well as nano- and biosciences because it provides valuable information about structure, functions, and reactions of molecules. In the meantime, quantum chemical approaches play crucial roles in the spectral analysis. They also yield important knowledge about molecular and electronic structures as well as electronic transitions. The combination of spectroscopic approaches and quantum chemical calculations is a powerful tool for science, in general. Thus, our article, which treats various spectroscopy and quantum chemical approaches, should have strong implications in the wider scientific community. This review covers a wide area of molecular spectroscopy from far-ultraviolet (FUV, 120–200 nm) to far-infrared (FIR, 400–10 cm−1)/terahertz and Raman spectroscopy. As quantum chemical approaches, we introduce several anharmonic approaches such as vibrational self-consistent field (VSCF) and the combination of periodic harmonic calculations with anharmonic corrections based on finite models, grid-based techniques like the Numerov approach, the Cartesian coordinate tensor transfer (CCT) method, Symmetry-Adapted Cluster Configuration-Interaction (SAC-CI), and the ZINDO (Semi-empirical calculations at Zerner's Intermediate Neglect of Differential Overlap). One can use anharmonic approaches and grid-based approaches for both infrared (IR) and near-infrared (NIR) spectroscopy, while CCT methods are employed for Raman, Raman optical activity (ROA), FIR/terahertz and low-frequency Raman spectroscopy. Therefore, this review overviews cross relations between molecular spectroscopy and quantum chemical approaches, and provides various kinds of close-reality advanced spectral simulation for condensed phases.

Previous measurements of fundamental, first-, second- and third overtones of the OH-stretching vibration of phenol and 2,6-difluoro-phenol by use of visible (Vis), near-infrared (NIR) and infrared (IR) spectroscopy revealed an oscillating pattern in the intensity quotient between the two kinds of solvents, carbon tetrachloride and n-hexane, upon increase of the vibrational quantum number, which could not be reproduced utilizing quantum mechanical calculations in implicit solvation. In the present study this phenomenon was successfully explained for the first time, employing an explicit consideration of solute-solvent interactions in combination with modern grid-based methods to solve the time-independent Schrödinger equation. The capabilities of this framework of (i) not requiring any assumptions on the form of the resulting wave function, (ii) focusing the description on the vibrational mode of interest and (iii) taking solute-solvent interactions explicitly into account are a particularly lucid example of the advantages in applying state-of-the-art approaches in investigations of challenging vibrational quantum problems. The property of grid-based methods being directly applied onto any given potential energy grid together with point (i) enable to analyse the impact of mechanical- and electrical anharmonicity independently. Especially the detailed investigation of the latter contribution when moving from a harmonic to an anharmonic potential in conjunction with the explicit consideration of solvent effects at the example of an actual chemical system (i.e. not discussing these effects employing mere model potentials) demonstrate the manifold benefit achieved using the applied DFT/Numerov strategy.

To the best of our knowledge, the current study based on ab initio quantum mechanical charge field molecular dynamics (QMCF-MD) is the first to explore the difference in the hydration behavior between Mn(II)- and Mg(II)-associated porphyrins (Mn(II)-POR and Mg(II)-POR) in aqueous solution. The simulation study highlights similar and dissimilar characteristics of the structural, dynamical, and thermodynamical properties of these closely related metals bound to porphyrins in aqueous solution. The structural analysis is based on radial and angular distribution functions, coordination number distributions, and angular-radial distributions. Both hydrated systems demonstrate similar pentacoordinated structures formed via the axial coordination of one water molecule to the metal ion in addition to the four nitrogen atoms of the porphyrin ring. However, in the case of Mn(II)-POR, the formation of a distorted square pyramidal geometry was observed. It was envisaged as a weak coordination of the water molecule to the Mn(II) atom and thus higher atomic fluctuation for all atoms in contrast to that for the hydrated Mg(II)-POR. The dynamical data in terms of the mean residence times, velocity autocorrelation function, free energy, and other parameters revealed the difference in the metal binding effect because the Mn(II) atom was observed to inhibit H-bond formation more than the presence of Mg(II) atoms in the core of the porphyrin. The current study thus highlights the significant differences in the structural and dynamical properties of Mn(II)- and Mg(II)-associated porphyrin systems.

Adolescents experience more police-initiated contacts resulting from relatively minor infractions than any other group, and often these interactions do not result in notable legal consequences. However, such interactions may have long-term consequences for adolescent perceptions of the justice system. Using data from the age 15 wave of the Fragile Families and Child Wellbeing Study, our study examines associations between situational and process features of police contact and legal cynicism in adolescence, accounting for demographic characteristics, self-reported delinquency, neighborhood context, and stop outcome. Relative to youth who experienced only vicarious police contact, youth who had direct or both direct and vicarious police contact reported higher levels of legal cynicism. Youth perceptions of procedural justice were associated with lower legal cynicism. Situational features of police contact such as harsh language and frisking were related to higher legal cynicism. Directions for future research, including the need for longitudinal research on this topic, are discussed.

The adapted Numerov approach was extended to periodic problems and applied to the torsional tunneling splitting of six increasingly complex target systems carrying a hydroxy-group. The deviations from experiment remained on the order of 1 cm−1, except for phenol in which the exceptionally small ground-state tunneling-splitting of 0.0017 cm−1 was found in very good agreement with the experimental value of 0.0019 cm−1. Overall, the accuracy of the periodic Numerov approach for the treatment of torsional tunneling is on the same order as alternative approaches, but at a substantially reduced computational demand due to the restriction of the problem to the respective degree of freedom.

The solvation structure and dynamics of Cu2+ in 18.6 % aqueous ammonia have been investigated using an ab initio quantum mechanical charge field molecular dynamics (QMCF MD) simulation approach at the Hartree–Fock (HF) level of theory applying the LANL2DZ ECP and Dunning DZP basis sets for Cu2+, ammonia and water, respectively. During a simulation time of 20 ps, only NH3 molecules are observed within the first solvation shell of Cu2+, resulting in the formation of an octahedral [Cu(NH3)6]2+ complex. While no exchange of these ligands with the second solvation shell are observed along the simulation, the monitoring of the associated N-Ntrans distances highlight the dynamics of the associated Jahn-Teller distortions, showing on average 2 elongated axial (2.19 Å) and 4 equatorial Cu–N bonds (2.39 Å). The observed structural properties are found in excellent agreement with experimental studies. In addition, an NBO analysis was carried out, confirming the strong electrostatic character of the Cu2+–NH3 interaction.

Interfacial adsorption and dissociation of water molecules at the α-Al2O3(0001) surface were studied using a novel hybrid 2D-periodic Self-Consistent Charge Density Functional Tight-Binding/Molecular Mechanics Molecular Dynamics (SCC-DFTB/MM MD) simulation strategy. The (0001) surface of α-Al2O3 (C-plane) was considered to assess the structural and dynamical behavior of adsorbed water at the interface region. In-plane distribution profiles of oxygen and hydrogen with respect to the non-periodic z-coordinate provide detailed information on the ordering of monolayer adsorbed water molecules at the interface. Dissociation of water molecules occured on the picosecond time scale, indicated by the formation of an additional plane-H peak located at 0.056 nm. Along simulation 4.2 OH groups per nm2 were formed at the α-Al2O3(0001) surface.

An adapted formulation of the grid-based Numerov approach to solve Schrodinger’s equation has been extended to four-dimensional systems and applied to problems in vibrational spectroscopy. The advantage of this novel implementation is that no approximations or assumptions with respect to the wavefunctions are required and the achieved accuracy at a given stencil size is only limited by the selected grid-spacing. To validate this approach the vibrational eigenstates and the corresponding wavenumbers of the linear molecules CO 2 , BeH 2 and HCN were investigated. Based on a potential energy grid at CCSD(T)/cc-pVnZ (n = T, Q) level all fundamental wavenumbers could be reproduced with deviations of less than 1% of the experimental values. Furthermore, the hierarchical application of a one- to four-dimensional Numerov treatment provides detailed information about the increasing influence of inter-mode coupling in addition to the inherent account for anharmonic contributions. The associated vibrational states are eigenfunctions of the Numerov matrix eigenvalue problem. Since no vibrational basis functions have to be applied in this approach, the respective eigenstates are characterized using isosurfaces of the wavefunctions in the hyperplane x 4 = 0 . This enables the direct examination of the individual wavefunctions via suitable visualization tools and the assignment of the respective vibrational quantum numbers.

In this work, the self-consistent charge density functional tight-binding (SCC-DFTB) approach has been implemented into a recently developed two-dimensional periodic quantum mechanical/molecular me...

Structural and dynamical properties of Cu+ in 18.6% aqueous ammonia solution at 298.15 K have been investigated via quantum mechanical charge field molecular dynamics (QMCF MD). The QM region was set to a radius of 6.7 A to include the first and second solvation shell. The Hartree-Fock (HF) level was applied to calculate the ion-ligand and ligand-ligand interactions in the QM region using the LANL2DZ-ECP basis set for the ion and DZP-Dunning for the ligands. The Cu+ N and Cu+ O radial distribution functions showed maximum first shell probabilities at distances of 2.23 and 2.30 A, respectively. Predominantly, four NH3 molecules were found to form a tetrahedral [Cu(NH3)4]+ complex, although the formation of a short-lived intermediate [Cu(NH3)3H2O]+ complex was also observed. The mean residence times of NH3 and H2O ligands in the first solvation shell were estimated as 14.6 ps and 1.3 ps, respectively, reflecting the strong interaction between Cu+ and ammonia as well as the occurrence of rapid water exchange. The vibrational power spectrum of the Cu+ N vibration in the first solvation shell revealed a wave number of 252 cm−1 with a corresponding force constant of 43.0 Nm−1. In addition, an NBO analysis was carried out, confirming the strong electrostatic character of the Cu+ NH3 and Cu+ H2O interaction, and highlighting that the presence of H2O ligands may destabilize the first solvation shell.

Study question Is impaired sexual functioning correlated to sperm quality in cancer survivors? Summary answer Erectile dysfunction affects 25.0% of cancer survivors, independent of sperm quality. 22.9% of patients show symptoms consistent with a reduced testosterone level. What is known already Gonadotoxic treatment in male cancer patients can end up in reversible or permanent impaired spermatogenesis, testosterone insufficiency, and sexual dysfunction. Study design, size, duration In this prospective single-center study, sexual functioning was assessed in male cancer survivors, who underwent sperm cryopreservation at the Department of Gynecological Endocrinology and Reproductive Medicine, Medical University Innsbruck, Austria from 01/2010 to 12/2018. Sexual functioning was assessed between 03–12/2020 via two questionnaires: Aging Male Score (AMS) and International Index of Erectile Function (IEEF-EF). Participants/materials, setting, methods Thirty-five cancer survivors (testicular cancer: n = 16 [45.7%], hematological malignancies: n = 15 [42.9%], others: n = 4 [n = 11.4%]) filled in two questionnaires (AMS and IEEF-EF) during routine follow-up visit at the Department of Gynecological Endocrinology and Reproductive Medicine, Medical University Innsbruck and the Department of Urology, Medical University Innsbruck, Austria. Moreover, sperm quality was assessed and normozoospermia was defined in accordance with the 2010 WHO criteria (sperm concentration ≥15 million/mL, progressive motility ≥32%, and ≥4% normal morphology). Main results and the role of chance Mean age at sperm cryopreservation and follow-up visit was 25.1±4.2 and 31.9±6.3 years, respectively with a mean follow-up time of 81.4±12.5 months. Rate of erectile dysfunction was low (75.0% no dysfunction, 15.6% low dysfunction, 3.1% low-moderate dysfunction, 3.1% moderate, 3.1% severe dysfunction). Moreover, AMS score indicated no, low, moderate and severe symptoms consistent with a low testosterone level in 77.1%, 8.6%, 2.9%, and 2.9% of patients, respectively. Oligozoospermia was observed in up to 48% of the patients with TM and in only 23% patients with HM. Patients with TM showed significantly reduced sperm count (18.7 × 106/mL [5.3–43.0]) and total sperm count (42.4 × 106/ejaculate [13.3–108.5]) compared to HM (p = 0.03). There was no difference in sexual functioning between patients with HM or TM. Sexual functioning did no correlate with sperm count, progressive motility or morphology. Limitations, reasons for caution Although the study may be limited by its small sample size, it is the first to assess a correlation of sperm quality and sexual dysfunction in cancer survivors. Wider implications of the findings: As every fourth male cancer patient suffers from impaired sexual functioning after gonadotoxic treatment, this important topic should be addressed in clinical and scientific future. Future studies should focus on both, somatic and psychosomatic reasons for sexual dysfunction. Trial registration number none

Study question Within this prospective study, we aim to differentiate immune cell subpopulations in recurrent implantation failure (RIF) patients and fertile controls. Summary answer A misbalanced immune profile of NK cell subpopulations is present in RIF patients and might be a potential risk factor that requires further detailed analysis. What is known already So far, there is no conclusive opinion on the prognostic value of testing immune cell populations in women with RIF. Increased numbers of cytotoxic (CD56dimCD16bright) peripheral natural killer (pNK)-cells and CD56brightCD16dim mainly in the uterus occurring NK cells (uNK) seemed to be more prevalent in RIF patients. NK cell cytotoxicity is regulated by a complex interaction of activating and inhibiting receptors, such as the NKGD2 and natural cytotoxicity receptors including NKp46, NKp30 and NKp44. Dysregulated pNK cells could affect the adhesion and implantation of the embryo thereby contributing to RIF. Study design, size, duration Within this prospective study between March 2018 and August 2020 immune diagnostics of pNK cells and subpopulations as well as regulatory T-cells in RIF patients (defined as ≥ 3 failed fresh or frozen embryo transfers of good quality embryos (Istanbul criteria) and non-pregnant controls (nulli- and multipara) were performed using flow cytometry analysis. Participants/materials, setting, methods In total, n = 42 RIF and n = 85 controls were included. Absolute numbers and percentages of total lymphocytes of CD56dimCD16bright, CD56brightCD16dim NK cells, CD45+CD25+FoxP3+-regulatory T-cells and activation markers (CD57+, CD62L+, NKGD2+, NKp46+) were measured in patients and controls (n = 60 nulligravida, n = 25 para) in the mid-luteal phase. Statistical analysis was performed using SPSS Version 26 considering p Main results and the role of chance RIF patients showed significantly lower numbers and percentages of CD56dimCD16bright pNK cells (mean±SD per µl: 187,5±113,3 vs. 281,9±163,4 p = 0.001;%: 87,4±8,8 vs. 90,6±6,0 p = 0.017) and higher levels of CD56brightCD16dim pNK cells (mean±SD per%: 10,5±8,3 vs. 7,6±5,5 p = 0.021) compared to controls. Further, lower percentages of CD56dimCD16brightCD62L + (mean±SD per%: 23,5±11,1 vs. 32,0±14,0 p = 0.001), CD56dimCD16brightNKGD2 + (mean±SD per%: 94,0±6,8 vs. 96,4±4,2 p = 0.014) and CD56dimCD16brightNKp46 + (mean±SD per%: 65,8±19,5 vs. 76,1±14,0 p = 0.001) were observed in RIF patients (p Limitations, reasons for caution As controls composed out of not only nulli- but also multipara, higher levels of pNK cells in controls, could be induced by fetal microchimerism in multiparas, however, results remained significant after removing multipara from statistical analysis. Wider implications of the findings: These findings condense into the assumption of a non-linear association between NK cytotoxicity and successful pregnancy. A lower NK cytotoxicity in RIF patients could potentially lead to an altered immune environment impeding a successful implantation process. Trial registration number Drks00020803

The objectives were to analyze the effects of housing cow–calf pairs in drylots (DL) or pasture (PAST) on cow performance and reproduction as well as calf performance and behavior through feedlot receiving. Simmental × Angus (2 yr; 108/yr; 81 ± 15.3 d postpartum) spring-calving cows were stratified by age, body weight (BW), body condition score (BCS), and calf sex and allotted to six groups per year. Groups were randomly assigned to one of two treatments: DL or PAST. Cows in DL were limit-fed at maintenance and calves had ad libitum access to the cow diet in an adjacent pen. Pairs on PAST were rotationally grazed and calves received creep ad libitum 3 wk prior to weaning. On day 110, calves were fence-line weaned and behavior was observed on days 111 and 112. On day 116, calves were transported 272 km to a feedlot for a 42-d receiving period. Behavior was evaluated again on days 117 and 118. Data were analyzed using the MIXED procedure of SAS except reproductive data which was analyzed using the GLIMMIX procedure. Cows on DL had greater (P ≤ 0.01) BW and BCS at weaning. There were no differences (P ≥ 0.42) detected in reproductive data. Cows on DL had greater (P = 0.02) milk production. Calves on DL had greater BW (P ≤ 0.01) on day 55 and at weaning and greater preweaning average daily gain (ADG). There were treatment × time effects (P = 0.01) for lying and eating on days 111 and 112. More DL calves were eating in the morning and lying in the evening. More (P < 0.01) PAST calves were walking on day 111. Pasture calves vocalized more (P ≤ 0.01) on day 112. On day 117, more (P ≤ 0.05) pasture calves were lying and eating, and DL vocalized more. On day 118, treatment × time and treatment effects were detected (P ≤ 0.02) for lying and walking. More PAST calves were lying and more DL calves were walking. Drylot calves had greater (P ≤ 0.02) BW at the beginning and end of the receiving phase. Pasture calves had greater (P < 0.01) ADG and tended (P = 0.10) to have greater gain efficiency during feedlot receiving phase. In conclusion, housing cow–calf pairs in drylots improved BW, BCS, and milk production of cows but did not affect reproductive performance. Drylot calves had increased BW and ADG during the preweaning phase. Calf behavior at weaning and receiving was influenced by preweaning housing. Pasture calves had improved receiving phase ADG and feed efficiency but were still lighter than drylot calves after 42-d receiving phase.

The title compound, [Co(C5H5)(C10H9N2)]PF6, was synthesized from deprotonated 1-aminopyridinium iodide, followed by microwave-assisted nucleophilic aromatic substitution of iodo-cobaltocenium iodide. After anion exchange with potassium hexafluoridophosphate, the title compound crystallizes as orange prisms in the space group Pc. This very stable pyridine nitrene adduct is the first example of a cobaltocenium derivative, formally containing a nitrene nitrogen species.

The ordering effects in anthraquinone (AQ) stacking forced by thin-film application and its influence on dimer solubility and current collector adhesion are investigated. The structural characteristics of AQ and its chemical environment are found to have a substantial influence on its electrochemical performance. Computational investigation for different charged states of AQ on a carbon substrate obtained via basin hopping global minimization provides important insights into the physicochemical thin-film properties. The results reveal the ideal stacking configurations of the individual AQ-carrier systems and show ordering effects in a periodic supercell environment. The latter reveals the transition from intermolecular hydrogen bonding toward the formation of salt bridges between the reduced AQ units and a stabilizing effect upon the dimerlike rearrangement, while the strong surface-molecular interactions in the thin-film geometries are found to be crucial for the formed dimers to remain electronically active. Both characteristics, the improved current collector adhesion and the stabilization due to dimerization, are mutual benefits of thin-film electrodes over powder-based systems. This hypothesis has been further investigated for its potential application in sodium ion batteries. Our results show that AQ thin-film electrodes exhibit significantly better specific capacities (233 vs 87 mAh g-1 in the first cycle), Coulombic efficiencies, and long-term cycling performance (80 vs 4 mAh g-1 after 100 cycles) over the AQ powder electrodes. By augmenting the experimental findings via computational investigations, we are able to suggest design strategies that may foster the performance of industrially desirable powder-based electrode materials.

Considering porous materials as host matrices is an elegant way to enable photoswitching of non-covalently attached organic dyes even in the solid state. By focusing on the resulting optical properties as a function of loading degree and synthesis procedure, the occurring host-guest and guest-guest interactions can be determined and further exploited. In the course of this study, the photochromic behavior of

In order to understand the evolution of the climate of Antarctica, dominant processes that control surface and low-atmosphere meteorology need to be accurately captured in climate models. We used the regional climate model MAR (v3.11) at 10 km horizontal resolution, forced by ERA5 reanalysis over a 9-year period (2010–2018) to study the impact of drifting snow (designating here the wind-driven transport of snow particles below and above 2 m) on the near-surface atmosphere and surface in Adelie Land, East Antarctica. Two model runs were performed, one with and one without drifting snow, and compared to half-hourly in situ observations at D17, a coastal and windy location of Adelie Land. We show that sublimation of drifting-snow particles in the atmosphere drives the difference between model runs and is responsible for significant impacts on the near-surface atmosphere. By cooling the low atmosphere and increasing its relative humidity, drifting snow also reduces sensible and latent heat exchanges at the surface (−5.7 W m−2 on average). Moreover, large and dense drifting-snow layers act as near-surface cloud by interacting with incoming radiative fluxes, enhancing incoming longwave radiation and reducing incoming shortwave radiation in summer (net radiative forcing: 5.7 W m−2). Even if drifting snow modifies these processes involved in surface–atmosphere interactions, the total surface energy budget is only slightly modified by introducing drifting snow because of compensating effects in surface energy fluxes. The drifting-snow driven effects are not prominent near the surface but peak higher in the boundary layer (fourth vertical level, 12 m) where drifting-snow sublimation is the most pronounced. Accounting for drifting snow in MAR generally improves the comparison at D17, especially for the representation of relative humidity (mean bias reduced from −14.0 % to −0.7 %) and incoming longwave radiation (mean bias reduced from −20.4 W m−2 to −14.9 W m−2). Consequently, our results suggest that a detailed representation of drifting-snow processes is required in climate models to better capture the near-surface meteorology and surface–atmosphere interactions in coastal Adelie Land.

In this chapter, the quantum mechanical basis for computational studies of near-infrared spectra (NIR) is discussed. Since this topic is rarely covered in detail in the literature, the necessary prerequisites are provided as well, which include (i) the coordinate frame for the description of molecular vibrations, (ii) methods for the determination of the vibrational potential, (iii) the principles of the harmonic approximation, and (iv) its role as the foundation for methods taking anharmonic effects into account. The details of various anharmonic approaches in quantum vibrational spectroscopy are discussed, including methods based on the vibrational self-consistent field (VSCF) approach, vibrational perturbation theory (VPT) as well as one- and multidimensional grid-based methods. The merits and pitfalls of these approaches are critically assessed from the perspective of applications in NIR spectroscopy. Selected examples from recent literature are included to demonstrate how these methods can be applied to solve practical problems in spectroscopy. The aim of this chapter is to provide a comprehensive presentation of the topic aimed at a spectroscopic audience, while remaining accessible and focused on the key details. Although primarily intended for readers interested in NIR spectroscopy, the essential information provided in this chapter represents a fundamental perspective on quantum vibrational absorption spectroscopy and is useful for a more general readership as well.

Near-infrared (NIR) spectroscopy is a powerful tool in studies of physicochemical properties of various kinds of samples. In particular, NIR spectroscopy contributed considerable to our understanding of intermolecular interactions (e.g. hydrogen bonding), molecular structure, solvent effect, clustering, phase transitions, kinetics. Because of mechanical and electrical anharmonicity of molecular vibrations, NIR spectra provide unique information not available from the other spectral regions. On the other hand, to elucidate useful information from NIR spectra, more sophisticated methods of data analysis than those applied in mid-infrared (mid–IR, MIR) region are necessary. This chapter presents selected examples demonstrating the variety of problems in the field of physical chemistry that have been studied by NIR spectroscopy.

To the best of our knowledge, this is the first molecular dynamics simulation study on the dimeric form of the LuxS enzyme from

In this work a newly parametrised Coulomb plus Buckingham potential formulation for cubic ZrO2, Y2O3 and yttrium-stabilised zirconia (YSZ) is presented. The density and pair distributions obtained for neat ZrO2 and Y2O3 under ambient conditions are in excellent agreement with experimental data, while the vibrational power spectra are highly similar compared to those obtained via ab initio molecular dynamics simulations at the PBEsol level. In addition, it is shown that the use of effective partial charges has several advantages compared to interaction potentials employing the oxidation states in the evaluation of the coulombic interactions: (i) the diffusion coefficient and the associated activation energy of oxygen ions evaluated for YSZn (n = 4 to 12) display the best agreement with experimental data; (ii) no unphysical reorganisation of the interface and the bulk are observed in simulations of the (110) and (111) surfaces of cubic ZrO2 and Y2O3, while due to the strong coulombic contributions in the case of the tested full-charge models a pronounced restructuring of the interface and the bulk is observed in the ZrO2 case, and (iii) the use of effective partial charges ensures compatibility with existing solvent models and force-fields for the treatment of molecular compounds.

Inspired by natural photosynthesis, features such as proton relays have been integrated into water reduction catalysts (WRC) for effective production of hydrogen. Research by DuBois et al. showed the crucial influence of these relays, largely in the form of pendant amine functions. In this work catalysts are presented containing innovative diphosphinoamine ligands: [M(ii)Cl2(PNP-C1)], [M(ii)(MeCN)2(PNP-C1)]2+, [M(ii)(PNP-C1)2]2+, and [M(ii)Cl(PNP-C2)]+ (M = Pt2+, Pd2+, Ni2+, Co2+; PNP-C1 = N,N-bis{(di(2-methoxyphenyl)phosphino)methyl}-N-alkylamine, PNP-C2 = N,N-bis{(di(2-methoxyphenyl)phosphino)ethyl}-N-alkylamine and alkyl = Me, Et, iso-Pr, Bz). Synthetic strategies and detailed characterisation are covered, including 1H-, 13C-, and 31P-NMR analysis, mass spectroscopy and single crystal X-ray diffractometry (XRD). The catalytic properties have been explored by changing the pendant amines and auxiliary methoxy coordination sites, as well as enlarging the ligand backbone. Moreover, confirmed by density functional theory (DFT) calculations based on XRD data in vacuo and solvent environment, two very different catalytic cycles are proposed. PNP-C1 shows a classical proton relay, whereas PNP-C2 allows an additional coordination of nitrogen, acting optionally like a pincer. Through new insights into efficiency and stability-increasing influences of proton relays in general, their number per metal centre, an enlarged ligand backbone and the use of solvato instead of halogenido complexes, substantial improvements have been made in catalytic performance over the DuBois et al. catalysts and recently self-made WRCs. The turnover number (TON) related to the single site of cost-efficient nickel WRCs is increased from 11.4 to 637, whereas a corresponding palladium catalyst gives TON as high as 2289.

A recently proposed thermodynamic integration (TI) approach formulated in the framework of quantum mechanical/molecular mechanical molecular dynamics (QM/MM MD) simulations is applied to study the ...