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The electrochemical reduction of CO2 to diverse useful chemical products is a promising way to transform chemical industry to CO2-neutral production. The gas diffusion electrodes (GDE), which enhance the gas/liquid and the liquid/solid interface tremendously, are very suitable for the CO2 electroreduction. Even if no real contact of all three phases – gas, liquid, solid – occurs it is often referred to as triple-phase-boundary (TPB). This term will also used throughout this paper because even if not entirely correct it is well-established in literature. The high diffusivity of gaseous CO2 and shorter diffusion lengths of solved CO2 in such electrodes enable the utilization of high process current densities. Tin based catalysts are of interest for CO2 electroreduction due to the low cost, non-toxic properties and ability to produce formic acid/formate at high selectivity. In this presentation we will show the electrochemical deposition of Sn onto commercial and in-house fabricated carbon based GDEs from different electrolytes. Focused ion beam (FIB) etching was utilized to build a 3D model of the porous GDE. Scanning electron micrographs (SEM) of the electrodeposits showed that different layer morphologies are attainable by changing the deposition mode. A new method was developed for cleaning the GDE after electrochemical deposition. The distribution of Sn throughout the thickness of the GDE was investigated with computer tomography (CT). The initial electrochemical characterization tests of the Sn-loaded GDE, under laboratory operating conditions demonstrated promising results.

For lithium-sulfur batteries, porous carbon/sulfur composite cathodes are the primary solution to compensate the non-conductive nature of sulfur. The composition and structure of this class of cathodes are crucial to the electrochemical performance, achieved energy density and the stability of the cell. Electrochemical impedance spectroscopy is employed to investigate and correlate the electrochemical performance of lithium-sulfur batteries to the composition and microstructure of differently fabricated carbon/sulfur composite cathodes. A transmission line model is applied to identify different underlying electrochemical processes appearing in the impedance response of a range of porous carbon/sulfur cathodes. The integration of a lithium ring serving as a counter electrode coupled with advanced wiring has allowed an artifact-free recording of the cathode impedance at different states of charge with the aim to investigate the evolution of impedance during discharge/charge and the kinetics of charge transfer depending on the infiltration method and the utilized carbon host. It is shown that impedance response of this class of cathodes is highly diverse and the plausible underlying processes are discussed in details. To this end, quasi-solid-state and various polysulfide-based charge transfer mechanisms are identified and their time constants are reported.

A transimpedance amplifier circuit as well as an instrumental amplifier circuit were used to measure current densities of a zinc-air battery with an integrated segmented current collector foil. Error calculation showed that the transimpedance amplifier is superior to the used instrumental amplifier, but both methods provide valuable and consistent results. They both showed comparable results with operando insight into the current distribution of the battery. The knowledge about those distributions is essential to avoid fast degradation of battery materials and irreversible capacity loss due to heterogeneous dissolution of the anode during discharge. In this work we showed that oxygen starvation as well as gas flow rate leads to large current gradients. It was also demonstrated that heterogeneous current distributions on cathode side induces also a heterogenous dissolution behavior on the anode, resulting in irreversible capacity loss.

CD62L (L-Selectin) dependent lymphocyte infiltration is known to induce inflammatory bowel disease (IBD), while its function in the liver, especially in non-alcoholic steatohepatitis (NASH), remains unclear. We here investigated the functional role of CD62L in NASH in humans as well as in two mouse models of steatohepatitis. Hepatic expression of a soluble form of CD62L (sCD62L) was measured in patients with steatosis and NASH. Furthermore, CD62L&minus, /&minus, mice were fed with a methionine and choline deficient (MCD) diet for 4 weeks or with a high fat diet (HFD) for 24 weeks. Patients with NASH displayed increased serum levels of sCD62L. Hepatic CD62L expression was higher in patients with steatosis and increased dramatically in NASH patients. Interestingly, compared to wild type (WT) mice, MCD and HFD-treated CD62L&minus, mice were protected from diet-induced steatohepatitis. This was reflected by less fat accumulation in hepatocytes and a dampened manifestation of the metabolic syndrome with an improved insulin resistance and decreased cholesterol and triglyceride levels. Consistent with ameliorated disease, CD62L&minus, animals exhibited an enhanced hepatic infiltration of Treg cells and a strong activation of an anti-oxidative stress response. Those changes finally resulted in less fibrosis in CD62L&minus, mice. Additionally, this effect could be reproduced in a therapeutic setting by administrating an anti-CD62L blocking antibody. CD62L expression in humans and mice correlates with disease activity of steatohepatitis. CD62L knockout and anti-CD62L-treated mice are protected from diet-induced steatohepatitis suggesting that CD62L is a promising target for therapeutic interventions in NASH.

Introduction The National University Hospital is a tertiary hospital with around 6400 employees. A ‘Total Workplace Safety & Health’ program was started in 2014 by assessing organisational and individual health risks using a health survey, workplace visits, accident reports, results of staff health screening and an internet-administered survey regarding health, stress, behaviour, and program engagement. Interventions included evidence-based health screening, a ‘healthy-eating’ campaign introducing a traffic-light system identifying healthier food at worksite canteens, needle-stick injuries reduction programs and motivational campaigns to increase physical activity. In spring 2017 the impact evaluation started. We report on lessons learned on program implementation, methodology and results of this impact evaluation. Methods Barriers to program success and evaluation were assessed through quantitative and qualitative methods focus-group discussions, employee survey, vendor interviews and direct observations for Healthy-Eating and Physical-Activity Interventions , including environment assessment, plate-counts of meals, sedentary and eating behaviours, activity habits, acceptance of messages. Result Feedback for lifestyle/behavioural interventions suggests modest participation and unknown impact. Participation in medical programs increased (vaccination +30%), previously undiagnosed chronic diseases were identified (unclear/pathological results 5% high blood-pressure, 5% high blood-glucose, 11% cancer screenings), a follow-up process was implemented. Organisational and environmental barriers for long-term program success were identified. Great enthusiasm got the programs started but lack of planning for evaluation hinders impact assessment. Survey, focus-groups and observations are completed in July 2017. Discussion Lessons learned include: Clarify responsibilities and reporting lines, plan for monitoring/evaluation at the beginning, get a baseline, define program goals. Clearly defined and medical-style programs showed more positive results and participation. Lifestyle interventions need to set realistic targets. ‘Asking’ people on behaviour is notoriously biassed. Unplanned evaluations ‘ex-post’ are unsatisfactory or impossible. Only some programs are open for cost-effective evaluation on hindsight and coordination from the top is crucial for impactful interventions and their evaluation.

Figure S1. Bronchial hyperresponsiveness in C57BL6 mice in LPS-induced acute lung injury. Mice were instilled with 50 μL of LPS (4 mg/kg) or saline (controls) on day 0 and were mechanically ventilated 1, 4 or 10 days after ARDS induction. Mice of basal group were mechanical ventilated without prior i.t. instillation. (A-D) Lung function parameters resistance (Rrs), elastance (Ers), tissue damping (G) and tissue elastance (H) on day 1, 4 and 10 after ARDS-induction following acetylcholine stimulation (controls n = 4, ARDS group n = 6 per time point, means ± SEM). * p ≤ 0.05, ** p ≤ 0.01, *** p ≤ 0.001. (PDF 311 kb)

Figure S2. Bronchial hyperresponsiveness in RAG2−/− and wildtype mice in LPS-induced acute lung injury. Mice were instilled with 50 μL of LPS (4 mg/kg) on day 0 and were mechanically ventilated 1, 4 or 10 days after ARDS induction. (A-D) Lung function parameters resistance (Rrs), elastance (Ers), tissue damping (G) and tissue elastance (H) on day 1, 4 and 10 after ARDS-induction following acetylcholine stimulation) (n = 8 in each group at each time point, means ± SEM). * p ≤ 0.05, ** p ≤ 0.01, *** p ≤ 0.001. (PDF 304 kb)

Objectives To implement and evaluate a Total Workplace Safety and Health Project (Total WSH) at a security office in a Singapore university. Methods Total WSH is an integrated approach to the management of health and safety in the workplace. In the first phase of our project, we evaluated the gaps and challenges of the safety and health management system within the department, and gained understanding of the health status of the security officers, through assessment tools including a Basic Health Survey, workplace visits and semistructured interviews. Recommendations were subsequently discussed with the senior management for implementation in the intervention phase, with evaluation of process and outcome measures thereafter. Results Strong communication among all staff in the security office was noted, and this is related to the openness of staff across different management levels. All staff took part in the Basic Health Survey, which found that 91% have a “Good” or “Excellent” Work Ability Index. There is a high proportion of employees with chronic diseases and obesity. In addition, 36% of employees consume sweet drinks daily, while only 16% and 37% consume two servings of fruits and vegetables a day respectively. Recommendations were made related to the safety and health management system, and health promotion such as improving access to healthy food, facilitating physical activity during work, and implementing a chronic disease management system. These recommendations would be implemented from January 2017 onwards. Conclusion Total WSH is effective in enabling the holistic management of safety and health in the workplace.

Lithium-ion batteries are nowadays widely used in consumer electronics and electric vehicles. However, the application in electric vehicles poses new challenges to this battery technology. High energy and power densities, a high degree of safety and a long lifetime are important to meet the requirements of the customers. To improve lithium-ion batteries, it is necessary to gain a deeper understanding of electrochemical processes occurring during battery cycling. Operando characterization techniques are used to shed light on these processes. In particular, operando X-ray diffraction (XRD) and neutron diffraction are applied for the observation of phase changes of battery materials during cycling. Thereby, the lithiation and delithiation mechanism can be investigated depending on different factors like C-rate or temperature. The gained deeper understanding of the structural behavior of battery materials under various operating conditions leads to the improvement of battery management systems by increasing the performance and reducing degradation processes of batteries. The phase changes of state-of-the-art battery materials at room temperature are well understood but the influence of temperature on the phase evolution is barely investigated. Recent studies show that the classical staging mechanism of graphite [1, 2] does not occur at higher C-rates [3, 4] and elevated or low temperatures [5, 6] and instead, several stages coexist. During a rest period after charge or discharge, these phases can equilibrate [6]. The lithiation and delithiation mechanism does not only influence the charge and discharge behavior, but also the dimensional changes concurrently with the degradation of the electrodes [5]. Therefore, a deeper understanding of the structural behavior of battery materials under various operating conditions is needed to improve the material properties and adapt battery management systems to increase the performance of the battery and reduce degradation. At DLR, a new set-up was developed to investigate with operando XRD the phase evolution of battery materials during cycling at temperatures below room temperature. This method allows a readily characterization of battery materials at various temperatures and the identification of the temperature dependent intercalation mechanisms. [1] J. Besenhard and H.P. Fritz, The Electrochemistry of Black Carbons, Angew. Chem. Int. Ed. 22 (1983) 950-975. [2] J.R. Dahn, Phase diagram of LixC6, J. Phys. Rev. B. 44 (1991) 9170-9177. [3] H. He, C. Huang, C.-W. Luo, J.-J. Liu and Z.-S. Chao, Dynamic study of Li intercalation into graphite by in situ high energy synchrotron XRD, Electrochim. Acta. 92 (2013) 148-152. [4] N. Sharma and V.K. Peterson, Current-dependent electrode lattice fluctuations and anode phase evolution in a lithium-ion battery investigated by in situ neutron diffraction, Electrochim. Acta. 101 (2013) 79-85. [5] N.A. Cañas, P. Einsiedel, O.T. Freitag, C. Heim, M. Steinhauer, D.-W. Park and K.A. Friederich, Operando X-ray diffraction during battery cycling at elevated temperatures: A quantitative analysis of lithium-graphite intercalation compounds, Carbon. 116 (2017) 255-263. [6] V. Zinth, C. von Lüders, J. Wilhelm, S.V. Erhard, M. Hofmann, S. Seidlmayer, J. Rebelo-Kornmeider, W. Gan, A. Jossen and R. Gilles, Inhomogeneity and relaxation phenomena in the graphite anode of a lithium-ion battery probed by in situ neutron diffraction, J. of Power Sources. 361 (2017) 54-60.

In the last decades, the investigation of new secondary cells has been increased considerably. Very promising battery systems are the so called “Post Li-ion batteries” with metal anodes: metal-sulfur and metal-air (oxygen) batteries, in particular Li-sulfur and Li-air batteries. Li-sulfur battery is a promising system, due to its high theoretical capacity (1675 mAh/gsulfur), energy density (2500 Wh/kg), the low cost and non-toxicity of sulfur. Nevertheless, some of the drawbacks of lithium-sulfur batteries are the poor rechargeability and high self-discharge rates. Due to the low electrical conductivity of sulfur, electrical conductive material has to be added in order to encourage the electrochemical reaction. Furthermore, polysulfides of high order (Li2Sn with 2 ≤ n ≤ 8) dissolve in the electrolyte and can diffuse to the anode and react directly with lithium metal. This so-called shuttle mechanism causes irreversible loss of sulfur. Metal-oxygen cells exhibit highest theoretical energy densities. State-of-the-art metal-oxygen cells mainly suffer from severe cyclic aging and low Coulombic efficiency. One of the major challenges is the development of suitable electrolytes and electrocatalysts for the oxygen reduction and gas evolution reactions. One of the major limiting factors on performance and round-trip efficiency is the catalyst used. Today´s Lithium-air batteries still suffer from high charge- and discharge overpotentials caused by insufficient catalysts. The major goal is to reduce overpotentials by using bifunctional catalysts catalyzing both the oxygen reduction reaction (ORR) as well as the oxygen evolution reaction (OER). Noble metal catalysts show good performance on both reactions but with increasing prices of noble metals metal oxides have drawn attention recently. In the presentation new results from the production and characterization of Lithium-sulfur batteries and bifunctional cathodes for Li-air batteries will be shown.

Development of tumor immunotherapies focuses on inducing autoimmune responses against tumor-associated self-antigens primarily encoded by normal, unmutated genes. We hypothesized that such responses could be elicited by T cell homeostatic proliferation in the periphery, involving expansion of T cells recognizing self-MHC/peptide ligands. Herein, we demonstrate that sublethally irradiated lymphopenic mice transfused with autologous or syngeneic T cells showed tumor growth inhibition when challenged with melanoma or colon carcinoma cells. Importantly, the antitumor response depended on homeostatic expansion of a polyclonal T cell population within lymph nodes. This response was effective even for established tumors, was characterized by CD8+ T cell–mediated tumor-specific cytotoxicity and IFN-γ production, and was associated with long-term memory. The results indicate that concomitant induction of the physiologic processes of homeostatic T cell proliferation and tumor antigen presentation in lymph nodes triggers a beneficial antitumor autoimmune response.

One of the major drawbacks of renewable energy production is that efficient energy storage is required, due to the intermittent nature of wind and solar power. The EU funded Project “ZAS – Zinc Air Secondary batteries based on innovative nanotechnology for efficient energy storage” has the goal to overcome this drawback by developing a new generation of secondary zinc-air batteries. Zinc based metal-air batteries have the advantage of high energy density, because oxygen from ambient air is used without in-cell storage. As a consequence, lighter batteries are produced with the reversible available Zinc as the only limiting factor. However, before Zn-air batteries can be used as secondary elements some obstacles have to be overcome. The low cyclability of state of the art Zn-air batteries is caused by the passivation rate and dendrite growth of zinc, carbonate formation in the alkaline electrolytes, corrosion of cathode materials and flooding of the cathode. Due to the volume expansion of Zinc in alkaline Zn-air batteries, it is important to optimize the penetration depth of electrolyte into the porous structure of the cathode by an appropriate pore size distribution. Electrochemical impedance spectroscopy measurements were conducted for different applied electrolyte pressures and correlated to the electrolyte penetration depth and the electrochemical performance. To get a better understanding how the electrolyte infiltrates the porous structure, an electrolyte intrusion cell was build. The volume increase and decrease of the zinc during charge and discharge could be mimicked with the developed cell by electrolyte intrusion and extrusion. The effect of the pore size distribution is strongly reflected in this measurements. This test was done for electrodes at different stages of degradation, to see how the penetration characteristics change over the cycle life of the cathode and how a long life battery could be obtained. Additionally electrodes at different state of charge (SOC) were compared and, in addition, changes in hydrophilic and hydrophobic pore properties were studied.