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Purpose Intracranial rescue stent angioplasty is a bailout strategy for acute stroke patients in cases of unsuccessful endovascular thrombectomy due to underlying atherosclerotic stenosis. However, there is no consensus on a preprocedural and intraprocedural antiplatelet regimen. The aim of this single-centre study was to compare the safety and efficacy of emergency stenting in patients exhibiting intracranial atherosclerotic stenosis-related acute large-vessel occlusion with or without peri-interventional intravenous infusion of tirofiban. Materials and Methods We performed a retrospective analysis of 78 patients who were treated with rescuestent angioplasty between 2010 and 2019 due to acute ischaemic stroke. The patients were divided into 2 groups: those who received peri-interventional intravenous tirofiban and those who did not receive tirofiban. We compared clinical safety and functional outcomes in both treatment groups with symptomatic haemorrhage as the primary endpoint. Bivariate and multivariable logistic regression was performed to investigate the association between tirofiban and outcome measures. Results Thirty-seven patients were treated with intravenous tirofiban (47.4%), and 41 patients did not receive intravenous tirofiban (52.6%). Statistical analysis revealed no significant difference between the two groups in the rate of symptomatic haemorrhage (16.2% in the tirofiban group versus 14.6% in the control group, p = 0.847). The 3-month mortality (21.6% in the tirofiban group versus 17.1% in the control group, p = 0.611) and good functional outcomes according to the modified Rankin scale (45.9% versus 34.1%, p = 0.289) were comparable. Conclusion The results of our study suggest that the application of tirofiban for rescue stenting after failed mechanical thrombectomy is safe.

OBJECTIVE: The study aim was to investigate the use of a novel device, the Vscan Air™, for rapidly and effectively performing ultrasound in student teaching during the COVID-19 pandemic. MATERIAL AND METHODS: As part of the ultrasound practical course with integrated hands-on activity required by the regular medical curriculum, 100 medical students were instructed in the use of the Vscan Air™, including duplex mode. They then evaluated the quality of the ultrasound images obtained by the Vscan Air™ from previously selected organs. RESULTS: 100 students were interviewed (female n = 68, male n = 32; age >18 years n = 100). The rated image quality never fell below a mean of 3 for the examined organs and portal vein flow (liver 4,58; spleen 3,99; kidneys 4,29; aorta 4,16; Douglas/rectovesical space 4,14; portal vein 4,43; pancreas 3,53; Focused Assessment with Sonography for Trauma 4,38). Scores below 3 were found sporadically in ultrasounds of the spleen (n = 4), kidneys (n = 3), Douglas/rectovesical space (n = 2), and pancreas (n = 15). The liver was rated the lowest for 59 ratings. The portal vein was evaluated in 68 cases. The hepatic artery and hepatic veins could be also visualized in all 68 examinations. The aorta was evaluated in 62 cases. CONCLUSION: The Vscan Air™ technology offered adequate image quality and provided a new, fast and patient-oriented technique to support continuous ultrasound examinations and education of students, especially during a pandemic. Particularly noteworthy is the uncomplicated compliance with the required high level of hygiene.

Electrical power and distribution transformers in field operation regularly show significant deviation in the load noise level in comparison to the sound measurements in the test field of the manufacturer where controlled and standardised measurement conditions apply. The main reason therefore are (a) the changed acoustical ambient conditions on-site caused by sound reflection and diffraction effects of nearby obstacles; (b) changed structural and acoustical resonances, and (c) the different principal operation conditions on-site. Whereas at the factory tests a pure sinusoidal current with short-circuited secondary winding is applied for load noise determination, transformers on-site operate at changed load power factors (phase angle between voltage and load-current), loading beyond the rated power (overload, partial load) as well as harmonics in the load-current. Harmonic components in the power grid are caused primarily by nonlinear loads and by the nonlinear transfer characteristic of the power grid. Any electrical device which shows a nonlinear consumption of active power or a nonlinear change of the source impedance draws a distorted current waveform even if the supply voltage is sinusoidal. With the growing use of electrical and electronic devices, distorted waveforms in power supply grid by harmonics have been largely increased within the past years. Devices like variable speed drives, six-pulse bridge rectifiers used in power electronics, and discharge lamps draw a non-sinusodial but pulsating current. Whereas most electric devices generate solely odd harmonics, some devices with fluctuating power consumption generate odd, even and also interharmonic currents [1]. Load noise is generated by electromagnetic forces acting on transformer windings. The forces are proportional to the square of the load-current (Section 2.2). This quadratic response behaviour generates winding vibrations at frequencies beyond the power frequency. In case of harmonics in the load-current, the resulting magnetic force and noise components have harmonics as well- with a more complex frequency spectrum. The related increase of the load noise level must be considered in the estimation of the total noise level of transformers under real load conditions. The question arise how to predict the resulting noise level at these loading conditions to guarantee the maximum allowed sound level at the transformer site as requested by legislative regulations or the owners specification. Starting from basic principles, we describe and quantify the generation of harmonics in winding forces, winding vibrations and load noise of electrical transformers caused by load harmonics. A calculation scheme for a fast and practically accurate estimation of the increase in the load noise level for a given load spectrum presented. The effects of A-weighting and frequency-dependent sound radiation efficiency of transformers to the total noise level are discussed. Finally, three practical examples are given.

The optic nerve is surrounded by the extension of meningeal coverings of the brain. When the pressure in the cerebrospinal fluid increases, it causes a distention of the optic nerve sheath diameter (ONSD), which allows the use of this measurement by ultrasonography (US) as a noninvasive surrogate of elevated intracranial pressure. However, ONSD measurements in the literature have exhibited significant heterogeneity, suggesting a need for consensus on ONSD image acquisition and measurement. We aim to establish a consensus for an ONSD US Quality Criteria Checklist (ONSD US QCC).A scoping systematic review of published ultrasound ONSD imaging and measurement criteria was performed to guide the development of a preliminary ONSD US QCC that will undergo a modified Delphi study to reach expert consensus on ONSD quality criteria. The protocol of this modified Delphi study is presented in this manuscript.A total of 357 ultrasound studies were included in the review. Quality criteria were evaluated under five categories: probe selection, safety, positioning, image acquisition, and measurement.This review and Delphi protocol aim to establish ONSD US QCC. A broad consensus from this process may reduce the variability of ONSD measurements in future studies, which would ultimately translate into improved ONSD clinical applications. This protocol was reviewed and endorsed by the German Society of Ultrasound in Medicine.

A versatile electrochemical corrosion process was used to generate green rust (GR) on a steel substrate and to transform it into the trivalent iron-only oxygen evolution catalyst mossbauerite (GR*) upon a subsequent oxidation process. Besides being scalable, cheap, and time-efficient, the demonstrated procedure is based on earth-abundant and non-hazardous materials only. Oxidation of mixed-valence Fe2+/Fe3+ GR to GR* was achieved by chemical and electrochemical processes. The latter induces less grafting of interlayer CO32−, leading to less contraction of the interlayer space and a reduction in the observable stacking disorder. The direct electrodeposition of the catalyst on a conductive substrate enabled the first systematic study of the impact of grafting on the performance of GR* in the oxygen evolution reaction (OER). The materials subjected to chemical (GR*ChOx) and electrochemical oxidation (GR*ElOx) allowed obtaining a current density of 100 mA cm−2 at 1.82 V and 1.84 V, respectively, thus improving the electrocatalytic capabilities and outperforming the bare steel substrate operated in 1 M KOH solutions.

Optic nerve sheath diameter (ONSD) sonography is a reliable method for evaluation of intracranial pressure, yet there is a lack of reliable normal values. In the study described here, we established normal ONSD values in three different age groups and both sexes. One hundred eighty-seven volunteers without central nervous system disease were enrolled in this prospective study. ONSD measurements were taken in volunteers in the supine and upright positions and after application of positive end-expiratory pressure (PEEP). Normal ONSD values were 4.9-5.3 mm (patient age range: 20-85), with significant differences between men and women (p0.001). ONSD values increased with age (∆ = 0.34 mm, p0.001). There were no differences compared with the upright position but application of PEEP led to significantly increased ONSD values (∆ = 0.21 mm, p = 0.008). ONSD values increased with age, correlated well with the width of the third ventricle, were significantly lower in the female cohort and quickly responded to PEEP, especially in women.

Approximately one-third of patients with stroke show depressive symptoms. The so-called post-stroke depression (PSD) has a negative influence on mortality as well as physical and mental conditions. The aim of this study was to analyse the association between PSD and health-related quality of life (HRQOL) in patients with stroke. The analysis was based on data of 326 patients from the Stroke Cohort Augsburg (SCHANA Study) collected after the stroke event by interview and three months later using a postal survey. Depressive symptoms were measured with the Patient-Health Questionnaire (PHQ-9), subjective health status with the EuroQol 5D visual analogue scale (EQ-5D VAS), and HRQOL with the Stroke Impact Scale (SIS). Patients with depressive symptoms were compared to those without depressive symptoms in terms of sociodemographic characteristics and scores of the SIS and the EQ-5D VAS. Multiple linear regression models were calculated to investigate the association between PSD and subjective health status and HRQOL. Three months after the stroke, 17.8% of patients had depressive symptoms. Patients with PSD showed significantly worse SIS and EQ-5D VAS scores. In addition, an independent negative linear association between PSD and subjective health status and between PSD and all domains of SIS could be found. The study confirmed that PSD is common in patients with mild stroke and negatively related to all stroke-specific HRQOL domains. The results underline the importance of early screening for PSD in stroke patients since it may hinder a successful rehabilitation.

BackgroundPost-stroke fatigue is a common symptom after stroke. However, studies on the factors associated with early and late fatigue are scarce. The objective of this study was to identify variables associated with early and late fatigue.MethodsIn the German Stroke Cohort Augsburg (SCHANA) study, participants were interviewed during their hospital stay and completed a postal questionnaire 3 and 12 months post-stroke. Fatigue was assessed using the Fatigue Assessement Scale (FAS). In addition, depression was measured by the Patient Health Questionnaire (PHQ-9), general health status by the EQ-5D visual analog scale, and physical activity by the International Physical Activity Questionnaire (IPAQ). Multivariable regression models were used to determine the associations between FAS scores at 3 and 12 months post-stroke and demographic, psychosocial and health-related covariables.ResultsAmong 505 participants, the frequency of fatigue was 31.1% 3 months and 29.1% 12 months post-stroke. Prior stroke (ß = 2.37, p = 0.0076), prior diagnosis of depression (ß = 5.04, p = 0.0001), higher NIHSS (ß = 0.25, p = 0.0360) and higher PHQ-9 scores (ß = 0.55, p < 0.0001) were significantly associated with higher fatigue levels 3 months post-stroke. Additionally, younger age (ß = −0.07, p = 0.0219), a worse rating of general health at baseline (ß = −0.04, p = 0.0287) and low pre-stroke physical activity (ß = −0.0004, p = 0.0089) were significantly associated with higher fatigue levels 12 months after stroke.ConclusionsFatigue is a common and persisting symptom even in patients with mild impairment. Prior depressive disorder and early depressive symptoms were the most relevant predictors of both early and late fatigue.

BACKGROUND The objective of the STREAM Trial was to evaluate the effect of simulation training on process times in acute stroke care. METHODS The multicenter prospective interventional STREAM Trial was conducted between 10/2017 and 04/2019 at seven tertiary care neurocenters in Germany with a pre- and post-interventional observation phase. We recorded patient characteristics, acute stroke care process times, stroke team composition and simulation experience for consecutive direct-to-center patients receiving intravenous thrombolysis (IVT) and/or endovascular therapy (EVT). The intervention consisted of a composite intervention centered around stroke-specific in situ simulation training. Primary outcome measure was the 'door-to-needle' time (DTN) for IVT. Secondary outcome measures included process times of EVT and measures taken to streamline the pre-existing treatment algorithm. RESULTS The effect of the STREAM intervention on the process times of all acute stroke operations was neutral. However, secondary analyses showed a DTN reduction of 5 min from 38 min pre-intervention (interquartile range [IQR] 25-43 min) to 33 min (IQR 23-39 min, p = 0.03) post-intervention achieved by simulation-experienced stroke teams. Concerning EVT, we found significantly shorter door-to-groin times in patients who were treated by teams with simulation experience as compared to simulation-naive teams in the post-interventional phase (-21 min, simulation-naive: 95 min, IQR 69-111 vs. simulation-experienced: 74 min, IQR 51-92, p = 0.04). CONCLUSION An intervention combining workflow refinement and simulation-based stroke team training has the potential to improve process times in acute stroke care.

Background and purpose Reported cutoff values of the optic nerve sheath diameter (ONSD) for the diagnosis of elevated intracranial pressure (ICP) are inconsistent. This hampers ONSD as a possible noninvasive bedside monitoring tool for ICP. Because the influence of methodological differences on variations in cutoff values is unknown, we performed a narrative review to identify discrepancies in ONSD assessment methodologies and to investigate their effect on reported ONSD values. Methods We used a structured and quantitative approach in which each ONSD methodology found in the reviewed articles was categorized based on the characteristic appearance of the ultrasound images and ultrasound marker placement. Subsequently, we investigated the influence of the different methodologies on ONSD values by organizing the ONSDs with respect to these categories. Results In a total of 63 eligible articles, we could determine the applied ONSD assessment methodology. Reported ultrasound images either showed the optic nerve and its sheath as a dark region with hyperechoic striped band at its edges or as a single dark region surrounded by lighter retrobulbar fat. Four different ultrasound marker positions were used to delineate the optic nerve sheath, which resulted in different ONSD values and more importantly, different sensitivities to changes in ICP. Conclusions Based on our observations, we recommend to place ultrasound markers at the outer edges of the hyperechoic striped bands or at the transitions from the single dark region to the hyperechoic retrobulbar fat because these locations yielded the highest sensitivity of ONSD measurements for increased ICP.

Layered double hydroxides (LDHs) of various compositions have been shown to be potent photo- and electrocatalysts. Recently, mossbauerite, obtained by chemical oxidation of an all-iron, mixed-valen...

Mossbauerite, a trivalent iron-only layered oxyhydroxide, has been recently identified as an electrocatalyst for water oxidation. We investigated the material as potential cocatalyst for photoelect...

Background Much is known about the association between physical activity and the occurrence of stroke. However, the evidence about the correlation between pre-stroke physical activity and post-stroke quality of life remains inconsistent. Thus, there is a high public health relevance to the topic. Aim The aim of this study was to investigate the association between pre-stroke physical activity and physical quality of life after three months. Methods Data arises from 858 patients with stroke included a prospective single-centre observational cohort study in Augsburg, Germany, between September 2018 and November 2019. The participants were recruited at the Department of Neurology and Clinical Neurophysiology, University Hospital of Augsburg after their stroke event. The level of physical activity was determined following the short form of the International Physical Activity Questionnaire at baseline. Physical quality of life was assessed three months after hospital discharge using the German version of the Stroke Impact Scale (SIS). A multiple linear regression model and a quantile regression were carried out. Results A total of 497 patients were included in the analysis (mean age 69.6, 58.8% male), 26.2% had a high, 18.9% a moderate and 54.9% a low level of pre-stroke physical activity. Patients with high pre-stroke physical activity had a significantly better physical quality of life three months after stroke in the SIS physical domain (beta = 4.1) and in the SIS subdomains hand function (beta = 5.6), mobility (beta = 4.1) and activities of daily living (beta = 3.7). In the physical domain and the subdomain mobility, the effect was especially strong for persons with low physical quality of life after three months. Conclusion Pre-stroke physical activity seems to have an important and positive association with physical quality of life after three months in patients with mild disability. Further studies are needed to confirm these results.

BACKGROUND AND PURPOSE The optic nerve sheath diameter (ONSD) is a promising surrogate marker for the detection of raised intracranial pressure (ICP). However, inconsistencies in manual ONSD assessment are thought to affect ONSD and the corresponding ONSD cutoff values for the diagnosis of elevated ICP, hereby hampering the full potential of ONSD. In this study, we developed an image intensity-invariant algorithm to automatically estimate ONSD from B-mode ultrasound images at multiple depths.METHODS The outcomes of the algorithm were validated against manual ONSD measurements by two human experts. Each expert analyzed the images twice (M1 and M2) in unknown order.RESULTS The algorithm proved capable of segmenting the ONSD in 39 of 42 images, hereby showing mean differences of -.08 +/- .45 and -.05 +/- .41 mm compared to averaged ONSD values (M1 + M2/2) of Operator 1 and Operator 2, respectively, whereas the mean difference between the two experts was .03 +/- .26 mm. Moreover, differences between algorithm-derived and expert-derived ONSD values were found to be much smaller than the 1 mm difference that is expected between patients with normal and elevated ICP, making it likely that our algorithm can distinguish between these patient groups.CONCLUSIONS Our algorithm has the potential to improve the accuracy of ONSD as a surrogate marker for elevated ICP because it has no intrinsic variability. However, future research should be performed to validate if the algorithm does indeed result in more accurate noninvasive ICP predictions.

The urge for carbon-neutral green energy conversion and storage technologies has invoked the resurgence of interest in applying brucite-type materials as low-cost oxygen evolution reaction (OER) electrocatalysts in basic media. Transition metal layered hydroxides belonging to the brucite-type structure family have been shown to display remarkable electrochemical activity. Recent studies on the earth-abundant Fe3+ containing mossbauerite and Fe3+ rich Co-Fe layered oxyhydroxide carbonates have suggested that grafted interlayer anions might play a key role in OER catalysis. To probe the effect of such interlayer anion grafting in brucite-like layered hydroxides, we report here a systematic study on the electrocatalytic performance of three distinct Ni and Co brucite-type layered structures, namely, (i) brucite-type M(OH)2 without any interlayer anions, (ii) LDHs with free interlayer anions, and (iii) hydroxynitrate salts with grafted interlayer anions. The electrochemical results indeed show that grafting has an evident impact on the electronic structure and the observed OER activity. Ni- and Co-hydroxynitrate salts with grafted anions display notably earlier formations of the electrocatalytically active species. Particularly Co-hydroxynitrate salts exhibit lower overpotentials at 10 mA cm-2 (η=0.34 V) and medium current densities of 100 mA cm-2 (η=0.40 V) compared to the corresponding brucite-type hydroxides and LDH materials.

The goal of our research was to assess the possibility of reliable investigation of brain tissue stiffness using ultrasonographic brain parenchyma elastography with an intact temporal bone. We enrolled 108 patients after exclusion of intracranial pathology or healthy volunteers. All patients were subdivided by age into groups: 20–40, 40–60 and >60 y. For statistical analysis, the χ 2 test and t -test were used. The mean values, regardless of age and other parameters, were 3.34 kPa (SD = 0.59) on the left side and 3.33 kPa (SD = 0.58) on the right side. We found no correlation between the values, body mass index (r = 0.07, p = 0.48) and sex (t = −0.11, p = 0.91), but we observed a highly significant correlation between the values and age (r = 0.43, p 0.0001). We found ultrasonographic brain parenchyma elastography to be a valid, reproducible and investigator-independent method that reliably determines brain parenchyma stiffness. Normal values should serve as a reference for studies on various intracranial lesions.

Directional control on material properties such as mechanical moduli or thermal conductivity are of paramount importance for the development of nanostructured next-generation devices. Two-dimensional materials are particularly interesting in this context owing to their inherent structural anisotropy. Here, we compare graphene oxide (GO) and synthetic clay sodium fluorohectorite (Hec) with respect to their thermal transport properties. The unique sheet structure of both allows preparation of highly ordered Bragg stacks of these pure materials. The thermal conductivity parallel to the platelets strongly exceeds that perpendicular to them. We find a significant difference in the performance between GO and synthetic clay. Our analysis of the textured structure, size of the platelets, and chemical composition shows that Hec is a superior two-dimensional component to GO. Consequently, synthetic clay is a promising material for thermal management applications in electronic devices where electrically insulating materials are prerequisites.

Ultrasound shear wave elastography is well established in diagnostics of several parenchymatous organs and is recommended by respective guidelines. So far, research about applications in relevant neurological conditions is missing, especially in adults. Here we aimed to examine the method for the differentiation of ischemic (IS) and hemorrhagic strokes (HS) and cerebral mass effects. 50 patients with a confirmed diagnosis of HS or IS were enrolled in this prospective study. 2D shear wave elastography was performed on the ipsilateral and the contralateral side with a modified acoustic radiation force impulse (ARFI) technique (ElastPQ mode, Philips). Lesion volumetry was conducted based on computed tomography data for correlation with elastography results. Elastography measurements (EM) revealed a highly significant difference between IS and HS with mean values of 1.94 and 5.50 kPa, respectively (p 0.00 001). Mean values of brain tissue on the non-affected side were almost identical (IS 3.38 (SD = 0.63); HS 3.35 (SD = 0.66); p = 0.91). With a sensitivity of 0.98 and a specificity of 0.99, a cut-off value of 3.52 kPa for discrimination could be calculated. There was a significant correlation of mass effect represented by midline shift and EM values on the contralateral side (Pearson correlation coefficient = 0.68, p 0.0003). Ultrasound brain parenchyma elastography seems to be a reliable sonographic method for discriminating between large IS and HS and for detecting and tracking conditions of intracerebral mass effects. Die Ultraschall-Scherwellen-Elastografie ist bereits eine im klinischen Alltag etablierte Diagnostik für verschiedene parenchymatöse Organe und wird von den entsprechenden Leitlinien empfohlen. Bislang gibt es jedoch keine relevante Forschung zur Anwendung bei neurologischen Erkrankungen, insbesondere bei Erwachsenen. In der vorliegenden Arbeit wurde daher der Stellenwert zur Differenzierung von ischämischen (IS) und hämorrhagischen Schlaganfällen (HS) und bei intrazerebralen Masseneffekten untersucht. Es wurden 50 Patienten mit einem nachgewiesenen HS oder IS in diese prospektive Studie eingeschlossen. Eine 2D-Scherwellen-Elastografie wurde auf der ipsi- und kontralateralen Seite mittels einer modifizierten „acoustic radiation force impulse“ (ARFI)-Technik (ElatPQ-Modus, Philips) durchgeführt. Eine Computertomografie-basierte Läsionsvolumetrie zur Korrelation mit den Elastografiewerten wurde ergänzt. Die Elastografiemessungen (EM) zeigten hochsignifikant unterschiedliche Ergebnisse zwischen IS und HS mit jeweiligen Mittelwerten von 1,94 und 5,50 kPa (p 0,00 001). Die Mittelwerte auf der nicht betroffenen Seite waren dabei nahezu identisch (IS 3,38 (SD = 0,63); HS 3,35 (SD = 0,66); p = 0,91). Mit einer Sensitivität von 98 % und einer Spezifität von 99 % konnte ein Cut-off-Wert von 3,52 kPa für die Differenzierung herausgearbeitet werden. Es zeigte sich außerdem eine signifikante Korrelation zwischen Masseneffekten im Sinne einer Mittellinienverlagerung und den EM auf der kontralateralen Seite (Pearson-Korrelationskoeffizient 0,68; p 0,0003). Die Ultraschall-Scherwellen-Elastografie erweist sich als verlässliche Methode zur Unterscheidung von IS und HS und zur Erfassung und Nachbeobachtung intrazerebraler Masseneffekte.

Layered double hydroxides (LDHs) are presently among the best-performing oxygen evolution reaction (OER) electrocatalysts in alkaline media. The high activity of LDHs is due to synergistic effects between two transition metals as well as the layered structure which facilitates electron transfer. Because of a perfect match with the size of interlayer carbonate a ratio of 2:1 for the di- and tri-valent octahedral cations is energetically preferred. Here we present a strategy, where first mixed valent (Co2+1-zFe2+z)4 Fe3+2 - LDHs, with z values between 0 and 0.75 are synthesized, which are subsequently oxidized to Co2+Fe3+ LDH-type layered (oxy)hydroxides with an unusual high trivalent Fe content. Characterization of the chemically oxidized materials using bulk and surface techniques demonstrated the successful synthesis of LDH-like trivalent iron rich (Co2+)4-4z (Fe3+)2+4z (oxy)hydroxides with a final Fe content ranging from 33.3 to 83.3%. Current densities of up to 200 mA cm−2 were obtained at potentials lower than 1.7 V vs. RHE for (Co2+)4-4z (Fe3+)2+4z (oxy)hydroxides containing a maximum of 80% Fe.

BACKGROUND AND PURPOSE Early prognostication of the outcome in resuscitated post cardiac arrest (CA) patients remains challenging especially if treated with therapeutic hypothermia. Brain edema caused by hypoxic-ischemic encephalopathy (HIE) can indirectly be estimated by transorbital sonography (TOS) taking in account the optic nerve sheath diameter (ONSD). The prognostic value of this easy, safe, and reproducible technique was investigated in this study. METHODS A total of 49 patients, initially unconscious (Glasgow Coma Scale ≤6) after successful resuscitation, were enrolled into this prospective observational study. Sonographic ONSD measurements were performed twice on day of admission (day 0) and once on days 1 and 2 after CA. Beyond ONSD, established prognostic parameters like neuron specific enolase and gray-white matter ratios were assessed. Cerebral Performance Category (CPC) score served as outcome parameter. RESULTS A total of 15 (31.3%) patients had a good outcome (CPC-score 1-2), 8 patients (14.6%) had severe disability (CPC-score 3-4), and 26 (54.2%) had a fatal outcome (CPC-score 5). Already in the first measurement on day 0, nonsurvivors showed significantly higher ONSD values (P < .001). For predicting mortality, a threshold of 5.75 mm was calculated with a specificity of 100%. ONSD did not differ significantly depending on hypothermia (P = .7009). CONCLUSION Early and reliable prognostication of outcomes in patients with HIE can be simplified by ONSD values gathered with the use of TOS. Main advantages compared to other established markers are prognostication within the first 24 hours and independence from therapy with hypothermia. A higher level of accuracy can be reached by combining computed tomography (gray-to-white matter ratio values) and ONSD values.

Mossbauerite is investigated for the first time as an "iron-only" mineral for the electrocatalytic oxygen evolution reaction in alkaline media. The synthesis proceeds via intermediate mixed-valence green rust that is rapidly oxidized in situ while conserving the layered double hydroxide structure. The material catalyzes the oxygen evolution reaction on a glassy carbon electrode with a current density of 10 mA cm-2 at 1.63 V versus the reversible hydrogen electrode. Stability measurements, as well as post-electrolysis characterization are presented. This work demonstrates the applicability of iron-only layered double hydroxides as earth-abundant oxygen evolution electrocatalysts. Mossbauerite is of fundamental importance since as an all Fe3+ material its performance has no contributions from unknown synergistic effects as encountered for mixed valence Co/Ni/Fe LDH.

Zinc oxide (ZnO) nanoparticles were mesostructured by polybutadiene-block-poly(2-vinylpyridine) cylindrical polymer brushes as a template. Loading the positively charged vinylpyridine block with ZnO nanoparticles produced hybrid rods with high aspect ratio. Mesostructured ZnO nanotubes obtained by pyrolytic template removal show high activity in the photocatalytic degradation of ciprofloxacin using a continuous flow reactor and irradiation with terrestrial solar spectrum. In comparison with Degussa P25, a titanium dioxide photocatalyst, the degradation is 2.9 times faster. Due to its non-woven microstructure, the photocatalyst, moreover, can be easily separated from fluid reaction media by filtration.

Belatacept is an attractive option for immunosuppression after renal transplantation. Renal allograft function is superior when compared to calcineurin inhibitor (CNI) based therapy in &ldquo, de novo&rdquo, treated patients and it has also been proposed that individuals at high cardiovascular (CV) risk may benefit most. In this retrospective cohort study, we assessed the efficacy and safety of treating patients at high cardiovascular risk with Belatacept (n = 34, for 1194 observation months) when compared to a matched control group of 150 individuals under CNI immunosuppression (for 7309 months of observation). The estimated glomerular filtration rate (eGFR) increased for patients taking Belatacept but decreased during CNI-based therapy (+2.60 vs. &minus, 0.89 mL/min/1.73 m2/year, p = 0.006). In a multivariate Cox regression model, Belatacept remained the only significant factor associated with the improvement of eGFR (HR 4.35, 95%CI 2.39&ndash, 7.93). Belatacept treatment was not a significant risk factor for renal allograft rejection or graft loss. In terms of safety, the only significant risk factor for de novo cardiovascular events was a pre-existing cerebrovascular disease, but Belatacept was not associated with a significant risk reduction. Belatacept treatment was not associated with an increased risk of severe infections, cytomegalo virus (CMV) or BK-virus reactivation, malignancy or death in the multivariate Cox regression analysis. Belatacept is an efficient and safe option for patients after renal transplantation at high cardiovascular risk.

Mössbauerite, a trivalent iron-only layered oxyhydroxide, has been recently identified as an electrocatalyst for water oxidation. We investigated the material as potential cocatalyst for photoelectrochemical water oxidation on semiconductor photoanodes. The band edge positions of mössbauerite were determined for the first time with a combination of Mott-Schottky analysis and UV-vis diffuse reflectance spectroscopy. The positive value of the Mott-Schottky slope and the flatband potential of 0.34 V vs reversible hydrogen electrode (RHE) identifies the material as an n-type semiconductor, but bare mössbauerite does not produce noticeable photocurrent during water oxidation. Type-II heterojunction formation by facile drop-casting with WO

Background/Objectives: Meteorological factors seem to influence stroke incidence, however, the complex association between weather and stroke remains unclear. Possible explanations from the literature do not categorize into subdivisions of ischemic strokes, only have small patient numbers, or refer to a selection of isolated weather elements without investigating weather changes and more. Method: In this exploratory trial, almost 18,000 stroke cases from a single stroke center in Southern Germany were analyzed from 2006 to 2015 and classified into the main subgroups of strokes and subdivisions of ischemic stroke etiologies applying the Trial of Org 10172 in Acute Stroke Treatment classification. For each stroke event, the air mass classification was determined from a subset of 7 air mass categories. Relative excess morbidities were derived for the 7 different air mass categories, taking into account the day of the event and up to 2 and 5 days preceding the stroke event. Results: Statistically significant findings (α ≤0.1) reveal that dry tropical air masses were associated with a lower/higher risk for hemorrhagic (HEM)/macroangiopathic strokes (MAS), respectively. Dry polar air masses were associated with a higher risk for intracerebral bleedings and lower risk for ischemic stroke subtypes. Moist air masses were associated with a reduced incidence of MAS. A strong temperature increase 5 days prior to the event was associated with a lower risk of HEM strokes. Temperature increases were associated with lower risks for MAS and cardio-embolic strokes. Significant temperature decreases were associated with a higher risk of MAS. Conclusions: Temperature effects were dependent on both air masses and temperature changes within 5 days prior to the event and were associated with statistically relevant changes in stroke incidence. Decisive factors such as etiology, age, sex, and risk factors were also taken into account.

BACKGROUND AND PURPOSE Quantification of changes in optic nerve sheath diameter (ONSD) using ocular sonography (OS) constitutes an elegant technique for estimating intracranial and intraspinal pressure. Aortic aneurysm repair (AAR) is associated with a reasonable risk of increased spinal fluid pressure, which is largely dependent on the extent of aneurysm repair (supra- vs. infrarenal). The aim of this study was to compare ONSD measurements in patients with suprarenal AAR (sAAR) or infrarenal AAR (iAAR). METHODS Thirty patients who underwent elective endovascular repair of infrarenal aortic aneurysms (Group iAAR) were included in the study; the characteristics in these cases were prospectively analyzed and compared with those in a previously investigated group of 28 patients treated for suprarenal aortic aneurysms (Group sAAR). Six measurements of ONSDs were performed in each patient at five consecutive time points. Statistical analysis was performed using the Wilcoxon test. A P value < .05 was considered statistically significant. RESULTS A highly significant difference between pre- and postinterventional values could be detected in both patient groups (P < .01). In Group sAAR, there was a mean .3-mm increase of the ONSD, whereas in Group iAAR, a mean .2-mm decrease could be detected. Both groups roughly reached baseline values by the end of their inpatient stay. CONCLUSIONS ONSD changes seem to be a reliable marker to estimate spinal perfusion. Since OS provides a suitable bedside tool for rapid reevaluation, it may guide physicians in the identification and treatment of patients at high risk for spinal cord ischemia.

Introduction: In Germany, stroke is the third leading cause of death, with more than 60,000 fatalities out of approximately 260,000 cases (first-ever and recurrent strokes) each year. So far, there are only a few long-term studies investigating determinants of the natural course of the disease, especially in the era of mechanical thrombectomy. Materials and Methods: The prospective single-center stroke cohort Augsburg (SCHANA) study will include about 1000 patients treated for stroke in the University Hospital of Augsburg. Patients aged 18 years or older with a confirmed diagnosis of ischemic or hemorrhagic stroke are included in the study. Information on demographic characteristics, onset of symptoms, etiologic factors, comorbidities, quality of life, invasive and non-invasive treatment, complications, and laboratory parameters are collected during a personal interview conducted during the patients’ hospital stay and via a medical chart review. About 30 mL of blood is collected from each patient, and after processing and aliquoting, all blood specimens are frozen at −80° C. The study participants will be followed-up via postal questionnaires at three and 12 months after discharge from the hospital. Furthermore, mortality follow-ups will be conducted. Cox-regression analysis will be used to estimate relative risks. Conclusion: The SCHANA study will generate comprehensive data on the long-term course of the disease. In addition to the main outcomes, recurrent events and survival, patient-oriented outcomes such as health-related quality of life and depression are the focus of the study.

Objectives The investigation of tissue stiffness using 2-D shear wave elastography is already widely used in clinical practice and research for a variety of parenchymatous organs, with the exception of the brain. The goal of our research was to assess the possibility of reliable investigation of brain tissue stiffness using ultrasonographic brain parenchyma elastography with an intact temporal bone. Methods We enrolled 108 patients after exclusion of intracranial pathology or healthy volunteers. All patients were subdivided by age into groups: 20–40, 40–60 and >60 y. For statistical analysis, the χ 2 test and t-test were used. The mean values, regardless of age and other parameters, were 3.34 kPa (SD = 0.59) on the left side and 3.33 kPa (SD = 0.58) on the right side. Results We found no correlation between the values, body mass index (r = 0.07, p = 0.48) and gender (t = −0.11, p = 0.91), but we observed a highly significant correlation between the values and age (r = 0.43, p 0.0001 ). Additionally the values of the ipsilateral side of two patients with proof of ischemic stroke in neuroimaging were 1.58 and 2.35 kPa. One patient with proof of a hemorrhagic stroke showed a value of 10.98 kPa on the ipsilateral side. The values on the contralateral side were 3.49 and 4.72 and 3.57 kPa, respectively. Conclusions We found ultrasonographic brain parenchyma elastography to be a valid, reproducible and investigator-independent method that reliably determines brain parenchyma stiffness. As far as we know from MR-elastography (MRE) studies, our values are in agreement with measurements in the deep white matter (average elasticity of 3.0 kPa [SD = 0.2] within the age group of 60–69 y). This was the first study to prove the reliable ultrasonographic investigation of brain parenchyma stiffness with an intact temporal bone. In the little number of previous studies all patients were examined after parts of the skull having been removed before. Significance The distinct difference of values taken in normal tissue and in areas affected by ischemic or hemorrhagic stroke might disclose an innovative application of ultrasound elastography. Other possible applications might be the differential diagnosis of dementias or the identification of symptomatic lesions for epilepsy (temporal sclerosis), thereby complementing other imaging techniques with all the advantages of ultrasound applications (bedside method, easily repeatable, etc.). Future studies should deal with the examination of aforementioned patient cohorts and correlation with MRE values.

The implementation of inexpensive, Earth-abundant metals in typical noble-metal-mediated chemistry is a major goal in homogeneous catalysis. A sustainable or green reaction that has received a lot of attention in recent years and is preferentially catalyzed by Ir or Ru complexes is the alkylation of amines by alcohols. It is based on the borrowing hydrogen or hydrogen autotransfer concept. Herein, we report on the Co-catalyzed alkylation of aromatic amines by alcohols. The reaction proceeds under mild conditions, and selectively generates monoalkylated amines. The observed selectivity allows the synthesis of unsymmetrically substituted diamines. A novel Co complex stabilized by a PN5 P ligand catalyzes the reactions most efficiently.

BACKGROUND & PURPOSE Thoracic endovascular aortic repair (TEVAR) is associated with a reasonable risk of spinal ischemia. As cerebrospinal fluid pressure (CSFP) is correlated with the rate of paraplegia, a non-invasive method to estimate CSFP could help to estimate the patient's individual risk and guide the therapeutic approach. The quantification of the optic nerve sheath diameter (ONSD) using ocular sonography (OS) could be a suitable technique and was examined in the present study. METHODS 28 patients with TEVAR were included. Five consecutive measurements of the ONSD were performed in each patient. The first before the intervention (“baseline”), the next immediately postinterventional at the intensive care unit (post1), measurements 3, 4 (post2, post3) on day 1 and 2 after the intervention and number 5 (post4) before discharge. Statistical analysis was done using the Wilcoxon-test. A p-value < 0.05 was considered statistically significant. RESULTS A significant increase between baseline and post1-measurements (right eye: p = 0.006; left eye: p = 0.02) could be detected. A significant decrease was detected between post1 and post3 (right eye: p = 0.02; left eye: p < 0.01). A group of 5 patients had an additional increase of ONSD from post1 to post2, one of these patients developed a permanent paraplegia. Patients with spinal catheters had significantly lower ONSDs at nearly all time points. CONCLUSION The present study is the first to prospectively examine and prove the possibility to monitor CSFP changes in patients with TEVAR associated transient spinal edema using OS. Systematic factors as artificial ventilation and body positioning did not have a significant effect.

Objective: Positive end-expiratory pressure (PEEP) ventilation is used to prevent alveolar collapse and improve oxygenation. PEEP ventilation hinders venous backflow to the right atrium as well as venous outflow from the brain including the spinal cord. This may have an effect on cardiac output (CO) and could result in an elevation in intracranial pressure (ICP) — an important cause of secondary brain injury. The aim of this study was to investigate the effect of moderate changes in PEEP values on hemodynamics and cerebral perfusion in neurological patients experiencing respiratory failure. Methods: The study focused on 7 patients in a neurological intensive care unit who suffered from respiratory failure. Cerebral blood flow velocity was measured using transcranial color-coded duplex sonography (TCCS) while moderate changes in PEEP levels (10 cm, 7 cm or 5 cm H2O) were made to investigate cerebral arterial blood flow velocity, third ventricular diameter, and midline shift. Simultaneously, cardiac output was measured using a minimally invasive hemodynamic monitoring system (Vigileo® or PiCCO®). Results: Rising PEEPs resulted in a non-significant trend toward increased brain volume, as shown by a mild linear regression of changes in third ventricular diameter. However, no significant changes in cerebral blood flow parameters or hemodynamics values such as blood pressure, heart frequency or cardiac output, were noticed. Conclusion: Low to moderate changes in PEEP appear to increase brain volume slightly, but cerebral autoregulatory compensatory mechanisms are sufficient to stabilize cerebral perfusion pressure and intravasal volume status. The effects of these changes in PEEP may be challenging in patients with impaired cerebral autoregulation (for example, in patients after subarachnoid hemorrhage or severe brain trauma) as well as in patients requiring a high level of PEEP ventilation (that is, patients with acute respiratory distress syndrome). In such patients TCCS and cardiac hemodynamics monitoring are warranted.