Quality indicators in intensive care medicine for Germany - fourth edition 2022.

The measurement of quality indicators supports quality improvement initiatives. The German Interdisciplinary Society of Intensive Care Medicine (DIVI) has published quality indicators for intensive care medicine for the fourth time now. After a scheduled evaluation after three years, changes in several indicators were made. Other indicators were not changed or only minimally. The focus remained strongly on relevant treatment processes like management of analgesia and sedation, mechanical ventilation and weaning, and infections in the ICU. Another focus was communication inside the ICU. The number of 10 indicators remained the same. The development method was more structured and transparency was increased by adding new features like evidence levels or author contribution and potential conflicts of interest. These quality indicators should be used in the peer review in intensive care, a method endorsed by the DIVI. Other forms of measurement and evaluation are also reasonable, for example in quality management. This fourth edition of the quality indicators will be updated in the future to reflect the recently published recommendations on the structure of intensive care units by the DIVI.

Spin-dependent reactivity and spin-flipping dynamics in oxygen atom scattering from graphite.

The formation of two-electron chemical bonds requires the alignment of spins. Hence, it is well established for gas-phase reactions that changing a molecule's electronic spin state can dramatically alter its reactivity. For reactions occurring at surfaces, which are of great interest during, among other processes, heterogeneous catalysis, there is an absence of definitive state-to-state experiments capable of observing spin conservation and therefore the role of electronic spin in surface chemistry remains controversial. Here we use an incoming/outgoing correlation ion imaging technique to perform scattering experiments for O(3P) and O(1D) atoms colliding with a graphite surface, in which the initial spin-state distribution is controlled and the final spin states determined. We demonstrate that O(1D) is more reactive with graphite than O(3P). We also identify electronically nonadiabatic pathways whereby incident O(1D) is quenched to O(3P), which departs from the surface. With the help of molecular dynamics simulations carried out on high-dimensional machine-learning-assisted first-principles potential energy surfaces, we obtain a mechanistic understanding for this system: spin-forbidden transitions do occur, but with low probabilities.

Posttransplant nephrotic syndrome resulting from NELL1-positive membranous nephropathy.

Membranous nephropathy (MN) constitutes a major cause of nephrotic syndrome (NS) in adults. After kidney transplantation (KTx), both recurrent and de novo MN has been reported. In addition to PLA2R and THSD7A, recent identification of neural EGFL-like-1 protein, NELL1, as a potential disease antigen has enriched our understanding of MN pathogenesis. To date, NELL1-positive MN has only been described in native kidneys, but never been diagnosed in renal allografts. We here report on a 56-year-old male kidney transplant recipient suffering from amyotrophic lateral sclerosis (ALS), who developed NS 25 years after KTx. Allograft biopsy revealed NELL1-positive MN. Using specifically established immunoblotting techniques, we detected new-onset NELL1-IgG1, IgG3, and IgG4 antibodies in the patient´s serum correlating with the course of proteinuria. While primary renal disease was undetermined, MN recurrence seemed unlikely given the long-time span since KTx. By clinical investigation of de novo etiologies, we did not detect an underlying malignancy. However, previous self-medication with dimercaptopropane sulfonate (DMPS) and alpha lipoic acid (ALA) represented a potential trigger and cessation associated with partial remission of proteinuria. This report illustrates the first case of posttransplant NS due to NELL1-positive MN. Monitoring NELL1 antibodies in the serum promise to be a non-invasive diagnostic tool guiding disease management.

Fundamental mechanisms for molecular energy conversion and chemical reactions at surfaces.

The dream of theoretical surface chemistry is to predict the outcome of reactions in order to find the ideal catalyst for a certain application. Having a working ab initio theory in hand would not only enable these predictions but also provide insights into the mechanisms of surface reactions. The development of theoretical models can be assisted by experimental studies providing benchmark data. Though for some reactions a quantitative agreement between experimental observations and theoretical calculations has been achieved, theoretical surface chemistry is in general still far away from gaining predictive power. Here we review recent experimental developments towards the understanding of surface reactions. It is demonstrated how quantum-state resolved scattering experiments on reactive and nonreactive systems can be used to test front-running theoretical approaches. Two challenges for describing dynamics at surfaces are addressed: nonadiabaticity in diatomic molecule surface scattering and the increasing system size when observing and describing the dynamics of polyatomic molecules at surfaces. Finally recent experimental studies on reactive systems are presented. It is shown how elementary steps in a complex surface reaction can be revealed experimentally.

Electron transfer mediates vibrational relaxation of CO in collisions with Ag(111).

We report experimental results on the state-to-state vibrational relaxation of CO(v = 17) in collisions with Ag(111) at incidence translational energies between 0.27 eV and 0.57 eV. These together with previous results provide a comprehensive set of data on two molecules (CO and NO)-one open and one closed shell-and two metals (Ag and Au). In all four cases, the incidence vibrational energy has been varied over several eV. We find a unifying relation between the probability of vibrational relaxation and the energetics of electron transfer from the metal to the molecule. This argues strongly that electronic friction based theories are not capable of explaining these data.

Vibrational Relaxation of Highly Vibrationally Excited CO Scattered from Au(111): Evidence for CO- Formation.

Electronically nonadiabatic dynamics can be important in collisions of molecules at surfaces; for example, when vibrational degrees of freedom of molecules are coupled to electron-hole-pair (EHP) excitation of a metal. Such dynamics have been inferred from a host of observations involving multiquantum relaxation of NO molecules scattered from metal surfaces. Electron transfer forming transient NO- is thought to be essential to the nonadiabatic coupling. The question remains: is this behavior usual? Here, we present final vibrational state distributions resulting from the scattering of CO(vi = 17) from Au(111), which exhibits significantly less vibrational relaxation than NO(vi = 16). We explain this observation in terms of the lower electron affinity of CO compared to NO, a result that is consistent with the formation of a transient CO- ion being important to CO vibrational relaxation.

An axis-specific rotational rainbow in the direct scatter of formaldehyde from Au(111) and its influence on trapping probability.

The conversion of translational to rotational motion often plays a major role in the trapping of small molecules at surfaces, a crucial first step for a wide variety chemical processes that occur at gas-surface interfaces. However, to date most quantum-state resolved surface scattering experiments have been performed on diatomic molecules, and little detailed information is available about how the structure of nonlinear polyatomic molecules influences the mechanisms for energy exchange with surfaces. In the current work, we employ a new rotationally resolved 1 + 1' resonance-enhanced multiphoton ionization (REMPI) scheme to measure the rotational distribution in formaldehyde molecules directly scattered from the Au(111) surface at incidence kinetic energies in the range 0.3-1.2 eV. The results indicate a pronounced propensity to excite a-axis rotation (twirling) rather than b- or c-axis rotation (tumbling or cartwheeling), and are consistent with a rotational rainbow scattering model. Classical trajectory calculations suggest that the effect arises-to zeroth order-from the three-dimensional shape of the molecule (steric effects). Analysis suggests that the high degree of rotational excitation has a substantial influence on the trapping probability of formaldehyde at incidence translational energies above 0.5 eV.

Trapping-desorption and direct-scattering of formaldehyde at Au(111).

Nonreactive surface scattering of atoms, molecules and clusters can be almost universally described by two mechanisms: trapping-desorption and direct-scattering. A hard cube model with an attractive square well provides a zeroth order description of the branching ratio between these two mechanisms as a function of the incidence energy. However, the trapping process is likely to be enhanced by excitation of internal degrees of freedom during the collision. In this molecular beam surface scattering study, we characterize formaldehyde/Au(111) scattering using angle resolved time-of-flight techniques. The two mechanisms are found to compete in the range of the investigated normal incidence energies between 0.1 and 1.3 eV. Whereas at low incidence energies trapping-desorption dominates, direct-scattering becomes more likely at incidence energies above 0.37 eV. This incidence energy is slightly higher than the desorption energy which is found to be 0.32 ± 0.03 eV by temperature programmed desorption techniques. A simple hard cube model underestimates the observed trapping probabilities indicating the importance of trapping induced by excitation of internal molecular degrees of freedom.

Intermediate state dependence of the photoelectron circular dichroism of fenchone observed via femtosecond resonance-enhanced multi-photon ionization.

The intermediate state dependence of photoelectron circular dichroism (PECD) in resonance-enhanced multi-photon ionization of fenchone in the gas phase is experimentally studied. By scanning the excitation wavelength from 359 to 431 nm, we simultaneously excite up to three electronically distinct resonances. In the PECD experiment performed with a broadband femtosecond laser, their respective contributions to the photoelectron spectrum can be resolved. High-resolution spectroscopy allows us to identify two of the resonances as belonging to the B- and C-bands, which involve excitation to states with 3s and 3p Rydberg character, respectively. We observe a sign change in the PECD signal, depending on which electronic state is used as an intermediate, and are able to identify two differently behaving contributions within the C-band. Scanning the laser wavelength reveals a decrease of PECD magnitude with increasing photoelectron energy for the 3s state. Combining the results of high-resolution spectroscopy and femtosecond experiment, the adiabatic ionization potential of fenchone is determined to be IPaFen=(8.49±0.06) eV.

A 1 + 1' resonance-enhanced multiphoton ionization scheme for rotationally state-selective detection of formaldehyde via the à (1)A2 ← X[combining tilde] (1)A1 transition.

The formaldehyde molecule is an important model system for understanding dynamical processes in small polyatomic molecules. However, prior to this work, there have been no reports of a resonance-enhanced multiphoton ionization (REMPI) detection scheme for formaldehyde suitable for rovibrationally state-selective detection in molecular beam scattering experiments. Previously reported tunable REMPI schemes are either non-rotationally resolved, involve multiple resonant steps, or involve many-photon ionization steps. In the current work, we present a new 1 + 1' REMPI scheme for formaldehyde. The first photon is tunable and provides rotational resolution via the vibronically allowed à (1)A2 ← X[combining tilde] (1)A1 transition. Molecules are then directly ionized from the à state by one photon of 157 nm. The results indicate that the ionization cross section from the 4(1) vibrational level of the à state is independent of the rotational level used as intermediate, to within experimental uncertainty. The 1 + 1' REMPI intensities are therefore directly proportional to the à ← X[combining tilde] absorption intensities and can be used for quantitative measurement of X[combining tilde]-state population distributions.

Final rotational state distributions from NO(vi = 11) in collisions with Au(111): the magnitude of vibrational energy transfer depends on orientation in molecule-surface collisions.

When NO molecules collide at a Au(111) surface, their interaction is controlled by several factors; especially important are the molecules' orientation with respect to the surface (N-first vs. O-first) and their distance of closest approach. In fact, the former may control the latter as N-first orientations are attractive and O-first orientations are repulsive. In this work, we employ electric fields to control the molecules' incidence orientation in combination with rotational rainbow scattering detection. Specifically, we report final rotational state distributions of oriented NO(vi = 11) molecules scattered from Au(111) for final vibrational states between vf = 4 and 11. For O-first collisions, the interaction potential is highly repulsive preventing the close approach and scattering results in high-J rainbows. By contrast, these rainbows are not seen for the more intimate collisions possible for attractive N-first orientations. In this way, we reveal the influence of orientation and the distance of closest approach on vibrational relaxation of NO(vi = 11) in collisions with a Au(111) surface. We also elucidate the influence of steering forces which cause the O-first oriented molecules to rotate to an N-first orientation during their approach to the surface. The experiments show that when NO collides at the surface with the N-atom first, on average more than half of the initial vibrational energy is lost; whereas O-first oriented collisions lose much less vibrational energy. These observations qualitatively confirm theoretical predictions of electronically non-adiabatic NO interactions at Au(111).

The ν6 fundamental frequency of the à state of formaldehyde and Coriolis perturbations in the 3ν4 level.

Formaldehyde is the smallest stable organic molecule containing the carbonyl functional group and is commonly considered to be a prototype for the study of high-resolution spectroscopy of polyatomic molecules. The a-axis Coriolis interaction between the near-degenerate ν4 and ν6 (out-of-plane and in-plane wagging modes, respectively) of the ground electronic state has received extensive attention and is thoroughly understood. In the first excited singlet à (1)A2 electronic state, the analogous Coriolis interaction does not occur, because the à state suffers from a pseudo-Jahn-Teller distortion, which causes a double-well potential energy structure in the q4 (') out-of-plane coordinate, and which dramatically reduces the effective ν4 (') frequency. The ν4 (') frequency is reduced by such a great extent in the à state that it is the 3ν4 (') overtone which is near degenerate with ν6 ('). In the current work, we report the precise ν6 (') fundamental frequency in the à state, and we determine the strength of the a-axis Coriolis interaction between 3ν4 (') and ν6 ('). We also provide a rotational analysis of the ν4 (')+ν6 (') combination band, which interacts with 3ν4 (') via an additional c-axis Coriolis perturbation, and which allows us to provide a complete deperturbed fit to the 3ν4 (') rotational structure. Knowledge of the Coriolis interaction strengths among the lowest-lying levels in the à state will aid the interpretation of the spectroscopy and dynamics of many higher-lying band structures, which are perturbed by analogous interactions.

Vibrational Inelasticity of Highly Vibrationally Excited NO on Ag(111).

Multiquantum relaxation of highly vibrationally excited nitric oxide on noble metals has become one of the best studied examples of the Born-Oppenheimer approximation's failure to describe molecular interactions at metal surfaces. When first reported, relaxation of highly vibrationally excited NO occurring in collisions with Au(111) surfaces exhibited the largest vibrational inelasticity seen in molecule-surface collisions, and no system has been found to date exhibiting a greater vibrational inelasticity. In this work, we compare the relaxation of NO(v = 11) in scattering events on Ag(111) to that on Au(111). The relaxation probability and the average vibrational energy loss are much higher when scattering from Ag(111). We discuss possible reasons for this remarkable phenomenon, which may be related to the dissociation of NO, possible on Ag(111) at lower energy compared with Au(111).

Controlling an electron-transfer reaction at a metal surface by manipulating reactant motion and orientation.

The loss or gain of vibrational energy in collisions of an NO molecule with the surface of a gold single crystal proceeds by electron transfer. With the advent of new optical pumping and orientation methods, we can now control all molecular degrees of freedom important to this electron-transfer-mediated process, providing the most detailed look yet into the inner workings of an electron-transfer reaction and showing how to control its outcome. We find the probability of electron transfer increases with increasing translational and vibrational energy as well as with proper orientation of the reactant. However, as the vibrational energy increases, translational excitation becomes unimportant and proper orientation becomes less critical. One can understand the interplay of all three control parameters from simple model potentials.

Neuromuscular interaction of jaw and neck muscles during jaw clenching.

AIMS: To test the hypothesis that jaw muscles and specific neck muscles, ie, levator scapulae, trapezius, sternocleidomastoideus, and splenius capitis, co-contract at the different submaximum bite forces usually generated during jaw clenching and tooth grinding, and for different bite force directions. METHODS: Bite-force transducers that measured all three spatial force components were incorporated in 11 healthy subjects. The test persons developed feedback-controlled submaximum bite forces in a variety of bite-force directions. The electromyographic (EMG) activity of the levator scapulae, splenius capitis, and trapezius muscles was recorded, at the level of the fifth cervical vertebra, by use of intramuscular wire electrodes. The activity of the sternocleidomastoideus and masseter muscles was recorded by surface electrodes. For normalization of the EMG data, maximum-effort tasks of the neck muscles were conducted in eight different loading directions by means of a special force-transducer system. Differences between neck-muscle activity during chewing, maximum biting in intercuspation, and the force-controlled motor tasks were compared with the baseline activity of the various muscles by one-way repeated-measures analysis of variance. RESULTS: The results confirmed the hypothesis. Co-contractions of the neck muscles in the range of 3% to 10% of maximum voluntary contraction were observed. Significant (P < .05) activity differences were recorded as a result of the different force levels and force directions exerted by the jaw muscles. Long-lasting action potential trains of single motor units triggered by jaw clenching tasks were also detected. CONCLUSION: The findings support the assumption of a relationship between jaw clenching and the neck muscle activity investigated. The low level of co-contraction activity, however, requires further study to elucidate possible pathophysiological interactions at the level of single motor units.

Sulfur dioxide oxidation induced mechanistic branching and particle formation during the ozonolysis of ß-pinene and 2-butene.

Recent studies have suggested that the reaction of stabilised Criegee Intermediates (CIs) with sulfur dioxide (SO(2)), leading to the formation of a carbonyl compound and sulfur trioxide, is a relevant atmospheric source of sulfuric acid. Here, the significance of this pathway has been examined by studying the formation of gas phase products and aerosol during the ozonolysis of ß-pinene and 2-butene in the presence of SO(2) in the pressure range of 10 to 1000 mbar. For ß-pinene at atmospheric pressure, the addition of SO(2) suppresses the formation of the secondary ozonide and leads to highly increased nopinone yields. A complete consumption of SO(2) is observed at initial SO(2) concentrations below the yield of stabilised CIs. In experiments using 2-butene a significant consumption of SO(2) and additional formation of acetaldehyde are observed at 1 bar. A consistent kinetic simulation of the experimental findings is possible when a fast CI + SO(2) reaction rate in the range of recent direct measurements [Welz et al., Science, 2012, 335, 204] is used. For 2-butene the addition of SO(2) drastically increases the observed aerosol yields at higher pressures. Below 60 mbar the SO(2) oxidation induced particle formation becomes inefficient pointing to the critical role of collisional stabilisation for sulfuric acid controlled nucleation at low pressures.

Pressure dependent aerosol formation from the cyclohexene gas-phase ozonolysis in the presence and absence of sulfur dioxide: a new perspective on the stabilisation of the initial clusters.

The ozonolysis of cyclohexene is studied with respect to the pressure dependent formation of stable gas-phase products and secondary organic aerosol (SOA) as well as the influence of the presence of SO(2). In addition the rate coefficient for the initial reaction cyclohexene + O(3) was determined at 295 K. The observed increase in CO and ethene yields at low pressures and the absence of ketene in the product spectrum confirm previously proposed reaction pathways forming these decomposition products. An enhanced ethene formation at pressures below 300 mbar coincides with drastically decreased aerosol yields pointing to a high influence on SOA formation of chemical activation driven dynamics in the vinylhydroperoxide channel. The static reactor experiments at 450 mbar in the presence of SO(2) in the present study showed a similar sensitivity of additional particle formation to H(2)SO(4) number densities as found in near-atmospheric flow reactor experiments [Sipiläet al., Science, 2010, 327, 1243], a surprising result with regard to the very different experimental approaches. At low pressures (around 40 mbar) no significant new particle formation is observed even at high H(2)SO(4) concentrations. These findings indicate that the collisional stabilisation of initial clusters is an important aspect for SOA formation processes involving sulfuric acid and organic compounds. The results may have implications for geo-engineering strategies based on stratospheric sulfur injection, but caution is mandatory when room temperature laboratory results are extrapolated to stratospheric conditions.