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Background: Healthcare professionals in hospitals are exposed to a high level of professional stress, time pressure, workload, and often times poor organizational support. This makes them especially susceptible to burnout. In this pragmatic randomized controlled trial, we test the hypothesis that participation in a 9-week program (LAGOM) that was designed in close collaboration with healthcare professionals, incorporating both individual and organizational aspects reduces emotional exhaustion in healthcare professionals (primary outcome)., Methods: Eighty four nurses and physicians working at the Charité - Universitätsmedizin Berlin and the Immanuel Hospital Berlin are automatically randomized to the LAGOM program (n = 42) or to usual care (n = 42) in a one-to-one allocation rate. The primary outcome emotional exhaustion is measured by the Maslach Burnout Inventory-Human Services Survey at baseline, post-intervention, and 1-month follow-up via an online survey. Secondary outcomes include depersonalization, personal accomplishment, subjective stress, mental well-being, self-care, self-efficacy, working conditions, mindfulness, and adverse events. Electrophysiological measures for heart rate variation analysis are captured. The PRECIS-2 tool is used to characterize the degree of pragmatism in our trial. Data analysis and primary intention-to-treat analysis using repeated measures analysis of variance are performed blind to intervention allocation. Per-protocol, subgroup, and secondary outcome analyses are conducted exploratively. An advisory board consisting of various stakeholders accompanies the study process., Discussion: If LAGOM proves to be effective in reducing symptoms of burnout, the program could make an important contribution to tackling the problem of the very high burnout rates among healthcare professionals and become an integral part of preventive services offered by hospitals., Trial Registration: German Clinical Trials Register, DRKS00034060. Registered 31 May 2024., (© 2024. The Author(s).)

PURPOSE OF REVIEW: This health technology assessment aimed to systematically assess the efficacy and safety of yoga as therapy for burnout. Economic, ethical, legal, social and organizational aspects were considered as well. RECENT FINDINGS: Yoga as a therapy has been shown to have positive effects on a range of symptoms, including stress, anxiety and depression. Regarding work-related stress and burnout, the effects of yoga have mainly been examined in a preventative context. Meta-analyses revealed no effects on burnout severity comparing yoga with passive controls in general. Compared with passive controls, yoga had a positive effect on subjective stress. Compared to active control, yoga had an effect on the burnout subscale depersonalization on individual study level. Yoga may have positive effects on burnout, but the results are mixed. Common definitions and standardized diagnostic tools are necessary to improve research and further assess yoga as therapy for burnout. TRIAL REGISTRATION: The HTA is registered with PROSPERO, CRD42022299405, on 6th February 2022., (© 2024. The Author(s).)

Probing the architecture of neuronal circuits and the principles that underlie their functional organization remains an important challenge of modern neurosciences. This holds true, in particular, for the inference of neuronal connectivity from large-scale extracellular recordings. Despite the popularity of this approach and a number of elaborate methods to reconstruct networks, the degree to which synaptic connections can be reconstructed from spike-train recordings alone remains controversial. Here, we provide a framework to probe and compare connectivity inference algorithms, using a combination of synthetic ground-truth and in vitro data sets, where the connectivity labels were obtained from simultaneous high-density microelectrode array (HD-MEA) and patch-clamp recordings. We find that reconstruction performance critically depends on the regularity of the recorded spontaneous activity, i.e., their dynamical regime, the type of connectivity, and the amount of available spike-train data. We therefore introduce an ensemble artificial neural network (eANN) to improve connectivity inference. We train the eANN on the validated outputs of six established inference algorithms and show how it improves network reconstruction accuracy and robustness. Overall, the eANN demonstrated strong performance across different dynamical regimes, worked well on smaller datasets, and improved the detection of synaptic connectivity, especially inhibitory connections. Results indicated that the eANN also improved the topological characterization of neuronal networks. The presented methodology contributes to advancing the performance of inference algorithms and facilitates our understanding of how neuronal activity relates to synaptic connectivity., Competing Interests: The authors declare no competing interests., (Copyright: © 2024 Donner et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Reproducible functional assays to study in vitro neuronal networks represent an important cornerstone in the quest to develop physiologically relevant cellular models of human diseases. Here, we introduce DeePhys, a MATLAB-based analysis tool for data-driven functional phenotyping of in vitro neuronal cultures recorded by high-density microelectrode arrays. DeePhys is a modular workflow that offers a range of techniques to extract features from spike-sorted data, allowing for the examination of functional phenotypes both at the individual cell and network levels, as well as across development. In addition, DeePhys incorporates the capability to integrate novel features and to use machine-learning-assisted approaches, which facilitates a comprehensive evaluation of pharmacological interventions. To illustrate its practical application, we apply DeePhys to human induced pluripotent stem cell-derived dopaminergic neurons obtained from both patients and healthy individuals and showcase how DeePhys enables phenotypic screenings., Competing Interests: Declaration of interests M.F. is a cofounder of MaxWell Biosystems AG, which commercializes HD-MEA technology. The other authors declare no competing interests., (Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.)

The ongoing COVID-19 pandemic has been brought on by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The spike glycoprotein (S), which decorates the viral envelope forming a corona, is responsible for the binding to the angiotensin-converting enzyme 2 (ACE2) receptor and initiating the infection. In comparison to previous variants, Omicron S presents additional binding sites as well as a more positive surface charge. These changes hint at additional molecular targets for interactions between virus and cell, such as the cell membrane or proteoglycans on the cell surface. Herein, bottom-up assembled synthetic SARS-CoV-2 miniviruses (MiniVs), with a lipid composition similar to that of infectious particles, are implemented to study and compare the binding properties of Omicron and Alpha variants. Toward this end, a systematic functional screening is performed to study the binding ability of Omicron and Alpha S proteins to ACE2-functionalized and nonfunctionalized planar supported lipid bilayers. Moreover, giant unilamellar vesicles are used as a cell membrane model to perform competitive interaction assays of the two variants. Finally, two cell lines with and without presentation of the ACE2 receptor are used to confirm the binding properties of the Omicron and Alpha MiniVs to the cellular membrane. Altogether, the results reveal a significantly higher affinity of Omicron S toward both the lipid membrane and ACE2 receptor. The research presented here highlights the advantages of creating and using bottom-up assembled SARS-CoV-2 viruses to understand the impact of changes in the affinity of S for ACE2 in infection studies.

Aim: Healthcare professionals are at increased risk of burnout, primarily due to workplace-related stressors. The COVID-19 pandemic has further increased this risk. Different interventions exist with varying degrees of effectiveness; little is reported on the content and implementation of such programs. This review fills this gap, with attention to recent programs using digital components., Methods: PubMed, Embase, PsycInfo, and Google Scholar were searched between January 24th and 28th, 2022, limited to the last 5 years (≥2017). Articles were included if they (1) focused on stress reduction or burnout prevention for nurses and medical doctors within workplace health promotion for nurses or medical doctors, (2) included a digital program component, (3) were conducted in high-income country contexts, and (4) were clinical studies published in English or German. Data was extracted using a priori designed spreadsheets. A group of at least 2 authors at each stage carried out the screening, selection, and data extraction., Results: The search strategy identified 153 articles, all except 7 were excluded. Two studies were conducted in the USA, two in Spain, one in the Netherlands, Poland, and Korea each. Four studies used a randomized study design, all but one had a control group. A wide range of outcome measures was used. The types of interventions included an adapted mindfulness-based stress reduction program combined with aspects of behavioral therapies, cognitive behavioral therapy, or acceptance and commitment therapy. The digital components used were apps (4 studies), a digital platform, blended learning, and a web-based intervention (1 study each). Six studies focused on individual interventions, one included organizational interventions., Conclusion: Despite an acute burnout crisis in the healthcare sector, only seven recent interventions were found that integrated digital components. Several problems emerged during the implementation of the interventions that made it clear that organizational support is urgently needed for successful implementation. Although interventions for stress reduction and burnout prevention should combine individual and organizational measures to be as successful as possible, this was only partially the case in one of the intervention programs. The results of this scoping review can be used to further develop or optimize stress and burnout prevention programs., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Adam, Berschick, Schiele, Bogdanski, Schröter, Steinmetz, Koch, Sehouli, Reschke, Stritter, Kessler and Seifert.)

Imitation of cellular processes in cell-like compartments is a current research focus in synthetic biology. Here, a method is introduced for assembling an artificial cytoskeleton in a synthetic cell model system based on a poly(N-isopropyl acrylamide) (PNIPAM) composite material. Toward this end, a PNIPAM-based composite material inside water-in-oil droplets that are stabilized with PNIPAM-functionalized and commercial fluorosurfactants is introduced. The temperature-mediated contraction/release behavior of the PNIPAM-based cytoskeleton is investigated. The reversibility of the PNIPAM transition is further examined in bulk and in droplets and it could be shown that hydrogel induced deformation could be used to controllably manipulate droplet-based synthetic cell motility upon temperature changes. It is envisioned that a combination of the presented artificial cytoskeleton with naturally occurring components might expand the bandwidth of the bottom-up synthetic biology., (© 2022 The Authors. Macromolecular Bioscience published by Wiley-VCH GmbH.)

The extracellular matrix (ECM) plays an immense role in the homeostasis of tissues and organs, can function as a barrier for infectious agents, but is also exploited by pathogens during infection. Therefore, the development of well-defined 3D ECM models in the form of microcapsules to elucidate the interactions between ECM components and pathogens in confinement and study disease infectivity is important, albeit challenging. Current limitations are mainly attributed to the lack of biocompatible methods for the production of protein-based microcapsules. Herein, hollow ECM-based microcapsules from laminin-111 or laminin-111/collagen IV are generated to investigate the behavior of organisms within confined 3D extracellular matrices. Microcapsules are created using water-in-oil emulsion droplets stabilized by block copolymer surfactants as templates for the charge-mediated attraction of laminin or laminin-collagen proteins to the droplets' inner periphery, allowing for the formation of modular ECM-based microcapsules with tunable biophysical and biochemical properties and organism encapsulation. The release of E. coli-laden ECM-based protein microcapsules into a physiological environment revealed differences in the dynamic behavior of E. coli depending on the constitution of the surrounding ECM protein matrix. The developed ECM-based protein microcapsules have the potential to be implemented in several biomedical applications, including the design of in vitro infection models., (© 2023 The Authors. Advanced Healthcare Materials published by Wiley-VCH GmbH.)

Mainstreaming of ecosystem service approaches has been proposed as one path toward sustainable development. Meanwhile, critics of ecosystem services question if the approach can account for the multiple values of ecosystems to diverse groups of people, or for aspects of inter- and intra-generational justice. In particular, an ecosystem service approach often overlooks power dimensions and capabilities that are core to environmental justice. This article addresses the need for greater guidance on incorporating justice into ecosystem services research and practice. We point to the importance of deep engagement with stakeholders and rights holders to disentangle contextual factors that moderate justice outcomes on ecosystem service attribution and appropriation in socio-political interventions. Such a holistic perspective enables the integration of values and knowledge plurality for enhancing justice in ecosystem services research. This broadened perspective paves a way for transformative ecosystem service assessments, management, and research, which can help inform and design governance structures that nourish human agency to sustainably identify, manage, and enjoy ecosystem services for human wellbeing., (© 2022. The Author(s).)

Modern Graph Neural Networks (GNNs) provide opportunities to study the determinants underlying the complex activity patterns of biological neuronal networks. In this study, we applied GNNs to a large-scale electrophysiological dataset of rodent primary neuronal networks obtained by means of high-density microelectrode arrays (HD-MEAs). HD-MEAs allow for long-term recording of extracellular spiking activity of individual neurons and networks and enable the extraction of physiologically relevant features at the single-neuron and population level. We employed established GNNs to generate a combined representation of single-neuron and connectivity features obtained from HD-MEA data, with the ultimate goal of predicting changes in single-neuron firing rate induced by a pharmacological perturbation. The aim of the main prediction task was to assess whether single-neuron and functional connectivity features, inferred under baseline conditions, were informative for predicting changes in neuronal activity in response to a perturbation with Bicuculline, a GABA A receptor antagonist. Our results suggest that the joint representation of node features and functional connectivity, extracted from a baseline recording, was informative for predicting firing rate changes of individual neurons after the perturbation. Specifically, our implementation of a GNN model with inductive learning capability (GraphSAGE) outperformed other prediction models that relied only on single-neuron features. We tested the generalizability of the results on two additional datasets of HD-MEA recordings-a second dataset with cultures perturbed with Bicuculline and a dataset perturbed with the GABA A receptor antagonist Gabazine. GraphSAGE models showed improved prediction accuracy over other prediction models. Our results demonstrate the added value of taking into account the functional connectivity between neurons and the potential of GNNs to study complex interactions between neurons., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Kim, Chen, Hornauer, Emmenegger, Bartram, Ronchi, Hierlemann, Schröter and Roqueiro.)

Large bell-shaped calcite formations called "Hells Bells" were discovered underwater in the stratified cenote El Zapote on the Yucatán Peninsula, Mexico. Together with these extraordinary speleothems, divers found a white, cloudy turbid layer into which some Hells Bells partially extend. Here, we address the central question if the formation of the turbid layer could be based on microbial activity, more specifically, on microbially induced calcite precipitation. Metagenomic and metatranscriptomic profiling of the microbial community in the turbid layer, which overlaps with the pelagic redoxcline in the cenote, revealed chemolithoautotrophic Hydrogenophilales and unclassified β-Proteobacteria as the metabolic key players. Bioinformatic and hydrogeochemical data suggest chemolithoautotrophic oxidation of sulfide to zero-valent sulfur catalyzed by denitrifying organisms due to oxygen deficiency. Incomplete sulfide oxidation via nitrate reduction and chemolithoautotrophy are both proton-consuming processes, which increase the pH in the redoxcline favoring authigenic calcite precipitation and may contribute to Hells Bells growth. The observed mechanism of microbially induced calcite precipitation is potentially applicable to many other stagnant sulfate-rich water bodies., (© 2022 The Authors. Geobiology published by John Wiley & Sons Ltd.)

Extracellular vesicles (EVs) are fundamental for proper physiological functioning of multicellular organisms. By shuttling nucleic acids and proteins between cells, EVs regulate a plethora of cellular processes, especially those involved in immune signalling. However, the mechanistic understanding concerning the biophysical principles underlying EV-based communication is still incomplete. Towards holistic understanding, particular mechanisms explaining why and when cells apply EV-based communication and how protein-based signalling is promoted by EV surfaces are sought. Here, the authors study vesicle-induced receptor sequestration (VIRS) as a universal mechanism augmenting the signalling potency of proteins presented on EV-membranes. By bottom-up reconstitution of synthetic EVs, the authors show that immobilization of the receptor ligands FasL and RANK on EV-like vesicles, increases their signalling potential by more than 100-fold compared to their soluble forms. Moreover, the authors perform diffusion simulations within immunological synapses to compare receptor activation between soluble and EV-presented proteins. By this the authors propose vesicle-triggered local clustering of membrane receptors as the principle structural mechanism underlying EV-based protein presentation. The authors conclude that EVs act as extracellular templates promoting the local aggregation of membrane receptors at the EV contact site, thereby fostering inter-protein interactions. The results uncover a potentially universal mechanism explaining the unique structural profit of EV-based intercellular signalling., (© 2022 The Authors. Advanced Science published by Wiley-VCH GmbH.)

Objectives: As well as associated cardiovascular diseases (CVD) like heart attacks, stroke, or others, arterial hypertension shows rising incidence throughout the last decades. The risk of developing an elevated blood pressure is mostly based on environmental and behavioral factors. Therefore, guidelines usually base a first-line therapy on lifestyle modifications. Complementary medicine (CM) offers a wide range of therapies to support such and CM utilization is common among CVD. We sought to analyze CM utilization among participants particularly suffering from arterial hypertension and aimed to distinguish utilization rates of different therapy approaches and predicting factors on this part of health behavior., Design and Setting: This cross-sectional analysis was based on data of the 2017 National Health Interview survey (NHIS, n = 26,742; response rate 80,7%), performed among the US population., Main Outcome Measures and Results: Within the last 12 months, 22.7% of participants reported to suffer from arterial hypertension and they were less likely to have used CM (26.8% with versus 32.5% without hypertension). Consulting a homeopath or using mind-body-medicine was more common among participants without the diagnosis, while equal proportions had consulted a chiropractor, a naturopath, a practitioner of traditional medicine, or a practitioner of chelation therapy. Regarding mind-body medicine (MBM), individuals with hypertension most often used spiritual meditation (10.6%), yoga (5.7%), mindfulness meditation (3.2%), progressive relaxation (3.1%), mantra meditation (2.4%), guided imagery (1.9%), tai chi (1.5%), and qi gong (0.4%). CM use in individuals with hypertension was associated with female sex, higher education, and/or living in the Western or Midwest USA., Conclusion: Participants with arterial hypertension were less likely to utilize CM therapies than those without. Regarding prevention and therapy of the disease, especially MBM therapies show promising results but further research and better information for the general population is needed., (Copyright © 2022 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Cancer-related fatigue (CRF) is a burdensome sequela of cancer treatments. Besides exercise, recommended therapies for CRF include yoga, psychosocial, and mindfulness-based interventions. However, interventions conducted vary widely, and not all show a significant effect. This meta-analysis aimed to explore intervention characteristics related to greater reductions in CRF. We included randomized controlled trials published before October 2021. Standardized mean differences were used to assess intervention efficacy for CRF and multimodel inference to explore intervention characteristics associated with higher efficacy. For the meta-analysis, we included 70 interventions (24 yoga interventions, 31 psychosocial interventions, and 15 mindfulness-based interventions) with 6387 participants. The results showed a significant effect of yoga, psychosocial, and mindfulness-based interventions on CRF but with high heterogeneity between studies. For yoga and mindfulness-based interventions, no particular intervention characteristic was identified to be advantageous for reducing CRF. Regarding psychosocial interventions, a group setting and work on cognition were related to higher intervention effects on CRF. The results of this meta-analysis suggest options to maximize the intervention effects of psychosocial interventions for CRF. The effects of yoga and mindfulness-based interventions for CRF appear to be independent of their design, although the limited number of studies points to the need for further research.

By using electrostatic interactions as driving force to assemble vesicles, the droplet-stabilized method was recently applied to reconstitute and encapsulate proteins, or compartments, inside giant unilamellar vesicles (GUVs) to act as minimal synthetic cells. However, the droplet-stabilized approach exhibits low production efficiency associated with the troublesome release of the GUVs from the stabilized droplets, corresponding to a major hurdle for the droplet-stabilized approach. Herein, we report the use of pH as a potential trigger to self-assemble droplet-stabilized GUVs (dsGUVs) by either bulk or droplet-based microfluidics. Moreover, pH enables the generation of compartmentalized GUVs with flexibility and robustness. By co-encapsulating pH-sensitive small unilamellar vesicles (SUVs), negatively charged SUVs, and/or proteins, we show that acidification of the droplets efficiently produces dsGUVs while sequestrating the co-encapsulated material. Most importantly, the pH-mediated assembly of dsGUVs significantly improves the production efficiency of free-standing GUVs (i.e., released from the stabilizing-droplets) compared to its previous implementation.

In textbooks of psychiatry and/or neurology which appeared during the Nazi period, psychoanalysis is mostly treated unkindly, although they avoid antisemitic reasoning. Kurt Kolle accords Freud merely a historical role and favors the comprehensive psychotherapy cultivated from 1936 onwards at the "Göring Institute". There is however a remarkable contribution by Josef Reinhold (Jeseník/Czechoslovakia) showing considerable knowledge and demonstrating to which degree psychoanalysis could be acknowledged under the Nazi regime in an academic text written by a non-German author. Oswald Bumke who emerged in the 1920s as the most vehement critic of Freud expressed his rejection of psychoanalysis by completely deleting its discussion in the 1943 edition of his textbook. In a polemic pamphlet of 1938 he extended his fight to Adler and Jung in whom he found still too much Freud, albeit in disguise. His deputy Max Mikorey buttressed this attack by racist arguments. Both statements were part of the ongoing conflict of academic psychiatry with a Nazi psychotherapy increasingly gaining an independent standing. Prior to 1933, the Zeitschrift für die gesamte Neurologie und Psychiatrie had been the major forum of discussing psychoanalysis in psychiatric circles. This discussion petered out in 1934 after the Journal had published the first scholarly paper, which connected the profile of Freud's teachings with their being rooted in the Viennese upper Jewish bourgeoisie. There was a parallel process in the journal Der Nervenarzt., (© 2021. Springer Medizin Verlag GmbH, ein Teil von Springer Nature.)

Abstract: Studies have provided evidence that human cerebral organoids (hCOs) recapitulate fundamental milestones of early brain development, but many important questions regarding their functionality and electrophysiological properties persist. High-density microelectrode arrays (HD-MEAs) represent an attractive analysis platform to perform functional studies of neuronal networks at the cellular and network scale. Here, we use HD-MEAs to derive large-scale electrophysiological recordings from sliced hCOs. We record the activity of hCO slices over several weeks and probe observed neuronal dynamics pharmacologically. Moreover, we present results on how the obtained recordings can be spike-sorted and subsequently studied across scales. For example, we show how to track single neurons across several days on the HD-MEA and how to infer axonal action potential velocities. We also infer putative functional connectivity from hCO recordings. The introduced methodology will contribute to a better understanding of developing neuronal networks in brain organoids and provide new means for their functional characterization., Impact Statement: Human cerebral organoids (hCOs) represent an attractive in vitro model system to study key physiological mechanisms underlying early neuronal network formation in tissue with healthy or disease-related genetic backgrounds. Despite remarkable advances in the generation of brain organoids, knowledge on the functionality of their neuronal circuits is still scarce. Here, we used complementary metal-oxide-semiconductor (CMOS)-based high-density microelectrode arrays (HD-MEAs) to perform large-scale recordings from sliced hCOs over several weeks and quantified their activity across scales. Using single-cell and network metrics, we were able to probe aspects of hCO neurophysiology that are more difficult to obtain with other techniques, such as patch clamping (lower yield) and calcium imaging (lower temporal resolution). These metrics included, for example, extracellular action potential (AP) waveform features and axonal AP velocity at the cellular level, as well as functional connectivity at the network level. Analysis was enabled by the large sensing area and the high spatiotemporal resolution provided by HD-MEAs, which allowed recordings from hundreds of neurons and spike sorting of their activity. Our results demonstrate that HD-MEAs provide a multi-purpose platform for the functional characterization of hCOs, which will be key in improving our understanding of this model system and assessing its relevance for translational research., Supplementary Information: The online version contains supplementary material available at 10.1557/s43577-022-00282-w., Competing Interests: Conflict of interestAll authors declare that they have no competing interests., (© The Author(s) 2022.)

Introduction: Chronic pain is a frequent severe disease and often associated with anxiety, depression, insomnia, disability, and reduced quality of life. This maladaptive condition is further characterized by sensory loss, hyperalgesia, and allodynia. Blue light has been hypothesized to modulate sensory neurons and thereby influence nociception., Objectives: Here, we compared the effects of blue light vs red light and thermal control on pain sensation in a human experimental pain model., Methods: Pain, hyperalgesia, and allodynia were induced in 30 healthy volunteers through high-density transcutaneous electrical stimulation. Subsequently, blue light, red light, or thermal control treatment was applied in a cross-over design. The nonvisual effects of the respective light treatments were examined using a well-established quantitative sensory testing protocol. Somatosensory parameters as well as pain intensity and quality were scored., Results: Blue light substantially reduced spontaneous pain as assessed by numeric rating scale pain scoring. Similarly, pain quality was significantly altered as assessed by the German counterpart of the McGill Pain Questionnaire. Furthermore, blue light showed antihyperalgesic, antiallodynic, and antihypesthesic effects in contrast to red light or thermal control treatment., Conclusion: Blue-light phototherapy ameliorates pain intensity and quality in a human experimental pain model and reveals antihyperalgesic, antiallodynic, and antihypesthesic effects. Therefore, blue-light phototherapy may be a novel approach to treat pain in multiple conditions., Competing Interests: A. M. Reuss, D. Groos, M. Schröter, and R. Scholl declare no competing financial or nonfinancial conflict of interest. In the past 3 years, C. Maihöfner has worked as a consultant and speaker for the following companies: Allergan, Bionorica, Biotest, Grünenthal, GSK, Lilly, Novartis, and Daiichi Sankyo. The present work was performed in fulfillment of the requirements for obtaining the degree “Dr. med.” by Anna Maria Reuss.Sponsorships or competing interests that may be relevant to content are disclosed at the end of this article., (Copyright © 2021 The Author(s). Published by Wolters Kluwer Health, Inc. on behalf of The International Association for the Study of Pain.)

This meta-analysis systematically reviewed the evidence on standardized acceptance-/mindfulness-based interventions in DSM-5 anxiety disorders. Randomized controlled trials examining Acceptance and Commitment Therapy (ACT), Mindfulness-Based Cognitive Therapy (MBCT), and Mindfulness-Based Stress Reduction (MBSR) were searched via PubMed, Central, PsycInfo, and Scopus until June 2021. Standardized mean differences (SMD) and 95% confidence intervals (CI) were calculated for primary outcomes (anxiety) and secondary ones (depression and quality of life). Risk of bias was assessed using the Cochrane tool. We found 23 studies, mostly of unclear risk of bias, including 1815 adults with different DSM-5 anxiety disorders. ACT, MBCT and MBSR led to short-term effects on clinician- and patient-rated anxiety in addition to treatment as usual (TAU) versus TAU alone. In comparison to Cognitive Behavioral Therapy (CBT), ACT and MBCT showed comparable effects on both anxiety outcomes, while MBSR showed significantly lower effects. Analyses up to 6 and 12 months did not reveal significant differences compared to TAU or CBT. Effects on depression and quality of life showed similar trends. Statistical heterogeneity was moderate to considerable. Adverse events were reported insufficiently. The evidence suggests short-term anxiolytic effects of acceptance- and mindfulness-based interventions. Specific treatment effects exceeding those of placebo mechanisms remain unclear. Protocol registry: Registered at Prospero on November 3rd, 2017 (CRD42017076810)., (© 2021. The Author(s).)

Background: Prior research presented inconsistent results with less, equal or higher vaccination rates among patients using complementary medicine. Given that complementary medicine includes a wide range of therapies, variable vaccination patterns may occur within consultations with different professions. This analysis aims to to evaluate differences between categories of complementary medicine regarding vaccination behavior among US adults., Methods and Results: This analysis used data from the 2017 National Health Interview Survey (NHIS; n = 26,742; response rate 80.7%). Prevalences of flu vaccination, consultations with complementary medicine practitioners in the past 12 months and their potential interactions were examined. 42.7% of participants had received flu vaccination in the past 12 months, 32.4% had seen one or more complementary medicine practitioner. Users of any type of complementary medicine were as likely as non-users to have received a flu vaccination (44.8% users versus 41.7% non-users; p = 0,862; adjusted odds ratio [AOR] = 1.01, 95% confidence interval [CI] = 0.95-1.07). Regarding specific complementary medicine types, individuals consulting with naturopaths (p < 0.001; AOR = 0.67, 95 %CI = 0.54-0.82), homeopaths (p < 0.001; AOR = 0.55; 95 %CI = 0.44-0.69) and chiropractors (p = 0.016; AOR = 0.9, 95 %CI = 0.83-0.98) were less likely, while other complementary medicine approaches showed no significant association with flu vaccination behavior. Independent predictors for a flu shot were prior diabetes, cancer, current asthma, kidney disease, overweight and current pregnancy. As well, higher educational level, age, ethnicity, health insurance coverage and having seen a general physician or medical specialist in the past 12 months were also associated with a higher vaccination rate., Conclusions: Complementary medicine users were equally likely to receive an influenza vaccination compared with non-users. Different complementary therapies showed varied associations with vaccination behavior. Further analyses may be needed to distinguish influencing factors among patients' vaccination behavior., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Extracellular vesicles (EVs) are fundamental for intercellular communication and influence nearly every process in cell physiology. However, because of their intricate molecular complexity, quantitative knowledge on their signaling mechanisms is missing, particularly impeding their therapeutic application. We used a complementary and quantitative engineering approach based on sequential synthetic bottom-up assembly of fully functional EVs with precisely controlled lipid, protein, and RNA composition. We show that the functionalities of synthetic EVs are analogous to natural EVs and demonstrate their programmable therapeutic administration for wound healing and neovascularization therapy. We apply transcriptome profiling to systematically decode synergistic effects between individual EV constituents, enabling analytical dissection and a fundamental understanding of EV signaling.

A minimal synthetic cell should contain a substrate for information storage and have the capability to divide. Notable efforts were made to assemble functional synthetic cells from the bottom up, however often lacking the capability to reproduce. Here, we develop a mechanism to fully control reversible cargo loading and division of DNA-containing giant unilamellar vesicles (GUVs) with light. We make use of the photosensitizer Chlorin e6 (Ce6) which self-assembles into lipid bilayers and leads to local lipid peroxidation upon illumination. On the time scale of minutes, illumination induces the formation of transient pores, which we exploit for cargo encapsulation or controlled release. In combination with osmosis, complete division of two daughter GUVs can be triggered within seconds of illumination due to a spontaneous curvature increase. We ultimately demonstrate the division of a selected DNA-containing GUV with full spatiotemporal control-proving the relevance of the division mechanism for bottom-up synthetic biology.

Crop production is a crucial ecosystem service that requires a combination of natural and anthropogenic contributions to high and stable yields, which is a coproduction process. We analysed this coproduction based on nationally aggregated data for 15 major crops for 67 countries and the European Union with data for four time steps (2000, 2006, 2010, 2014). We found strong increases in fertilizer use, net capital stock and manure use intensity for lower-middle-income countries and stagnation or decrease of these for high-income countries. We used a multiple linear regression model predicting yield to distinguish the effect of anthropogenic contributions (crop-specific fertilizer use intensity, net capital stock intensity, manure use intensity) and natural contributions (crop-specific agricultural suitability, including soil characteristics, topography and climate). We found that in particular fertilizer use intensity, manure use intensity and agricultural suitability explained variation in yields to a considerable degree (R 2  = 0.62).

Background: To further improve treatment quality and patient orientation, a multiprofessional enhanced recovery after surgery (ERAS®) transformation program was initiated in our clinic in January 2020. The ERAS® treatment pathway for colorectal surgery was established in October 2020., Objective: The aim of the study was to show that the perioperative treatment quality can be increased by implementing a certified ERAS® program in the setting of a fast-track pathway that has been established since 2008., Material and Methods: The first ERAS® patients from October/November 2020 (ERAS®) were compared with those of a representative consecutive control cohort (pre-ERAS®) who had undergone interventions from August to December 2019. Patient care and data collection of the ERAS® patients were ensured by an ERAS® nurse in daily visits. For the comparison cohorts, the electronic patient files were analyzed and historical colon pathway data from our clinic from 2008 were used., Results and Conclusion: A total of 10 ERAS® and 50 pre-ERAS® patients were included. After the ERAS® transformation, an increase in overall compliance with ERAS® guideline recommendations from 45% (pre-ERAS®) to 75% (ERAS®) was achieved. The number of days to tolerance of solid food decreased from 2 days (pre-ERAS®) to 1 day (ERAS®). The general postoperative complication rate was comparable (22% pre-ERAS® vs. 20% ERAS®). Most noticeable was the reduction of the median hospital stay of 9 days in the historical cohort to 3 days after ERAS® implementation. We attribute the necessary high ERAS® pathway compliance of 75% to a successful combination of process standards and multiprofessional ERAS® teams.

Recent advances in the field of cellular reprogramming have opened a route to studying the fundamental mechanisms underlying common neurological disorders. High-density microelectrode-arrays (HD-MEAs) provide unprecedented means to study neuronal physiology at different scales, ranging from network through single-neuron to subcellular features. In this work, HD-MEAs are used in vitro to characterize and compare human induced-pluripotent-stem-cell-derived dopaminergic and motor neurons, including isogenic neuronal lines modeling Parkinson's disease and amyotrophic lateral sclerosis. Reproducible electrophysiological network, single-cell and subcellular metrics are used for phenotype characterization and drug testing. Metrics, such as burst shape and axonal velocity, enable the distinction of healthy and diseased neurons. The HD-MEA metrics can also be used to detect the effects of dosing the drug retigabine to human motor neurons. Finally, it is shown that the ability to detect drug effects and the observed culture-to-culture variability critically depend on the number of available recording electrodes., (© 2021 Wiley-VCH GmbH.)

Conservation efforts are increasingly supported by ecosystem service assessments. These assessments depend on complex multi-disciplinary methods, and rely on a number of assumptions which reduce complexity. If assumptions are ambiguous or inadequate, misconceptions and misinterpretations may arise when interpreting results of assessments. An interdisciplinary understanding of assumptions in ecosystem service science is needed to provide consistent conservation recommendations. Here, we synthesise and elaborate on 12 prevalent types of assumptions in ecosystem service assessments. These comprise conceptual and ethical foundations of the ecosystem service concept, assumptions on data collection, indication, mapping, and modelling, on socio-economic valuation and value aggregation, as well as about using assessment results for decision-making. We recommend future assessments to increase transparency about assumptions, and to test and validate them and their potential consequences on assessment reliability. This will support the taking up of assessment results in conservation science, policy and practice.

Over the last several decades, the light-harvesting protein complexes of purple bacteria have been among the most popular model systems for energy transport in excitonic systems in the weak and intermediate intermolecular coupling regime. Despite this extensive body of scientific work, significant questions regarding the excitonic states and the photo-induced dynamics remain. Here, we address the low-temperature electronic structure and excitation dynamics in the light-harvesting complex 2 of Rhodopseudomonas acidophila by two-dimensional electronic spectroscopy. We find that, although at cryogenic temperature energy relaxation is very rapid, exciton mobility is limited over a significant range of excitation energies. This points to the presence of a sub-200 fs, spatially local energy-relaxation mechanism and suggests that local trapping might contribute substantially more in cryogenic experiments than under physiological conditions where the thermal energy is comparable to or larger than the static disorder.

Lipid-based vesicles have found widespread applications in the life sciences, allowing for fundamental insights into membrane-based processes in cell biology and as carrier systems for drug delivery purposes. So far, mostly small unilamellar vesicles (SUVs) with diameters of ~100 nm have been applied as carrier systems for biomedical applications. Despite this progress, several systematic limitations have arisen due to SUV dimensions, e.g., the size and total amount of applicable cargo is limited. Giant unilamellar vesicles (GUVs) might offer a pragmatic alternative for efficient cargo delivery. However, due to the lack of reliable high-throughput production technologies for GUV-carrier systems, only little is known about their interaction with cells. Here we present a microfluidic-based mechanical droplet-splitting pipeline for the production of carrier-GUVs with diameters of ~2 μm. The technology developed allows for highly efficient cargo loading and unprecedented control over the biological and physicochemical properties of GUV membranes. By generating differently charged (between -31 and + 28 mV), bioligand-conjugated (e.g. with E-cadherin, NrCam and antibodies) and PEG-conjugated GUVs, we performed a detailed investigation of attractive and repulsive GUV-cell interactions. Fine-tuning of these interactions allowed for targeted cellular GUV delivery. Moreover, we evaluated strategies for intracellular GUV cargo release by lysosomal escape mediated by the pH sensitive lipid DOBAQ, enabling cytoplasmic transmission. The presented GUV delivery technology and the systematic characterization of associated GUV-cell interactions could provide a means for more efficient drug administration and will pave the way for hitherto impossible approaches towards a targeted delivery of advanced cargo such as microparticles, viruses or macromolecular DNA-robots., (Copyright © 2020 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Introduction: Yoga practice in common usage is often confined to the physical aspects of the comprehensive practice. The purpose of this study was to examine the use of two additional aspects of yoga as part of yoga practice, i.e. yogic breathing and meditation (YoBaM). Prevalence and predictors of YoBaM use among yoga practitioners in the US general population were analyzed., Method: Cross-sectional data from the 2012 and 2017 National Health Interview Survey (NHIS) (N = 61,267) was used. 12-month prevalence of yoga use and YoBaM use among yoga practitioners were analyzed descriptively for the two cohorts respectively. Logistic regression analyses were used to analyze sociodemographic and health-related predictors of YoBaM use among yoga practitioners., Results: 12-month prevalence of yoga use and YoBaM use were 8.9 % and 4.8 % respectively in 2012. In 2017, 13.3 % had practiced yoga in the past 12 months and 7.0 % had used YoBaM. Yoga practitioners aged between 50 and 64 compared to being 29 or younger, females, Hispanics and those experiencing mild to severe forms of psychological distress were more likely to use YoBaM as part of their yoga practice. Yoga practitioners living in the Midwest or in a relationship were less likely to use YoBaM., Conclusion: In recent years, the number of yoga practitioners in the US general population has considerably increased and YoBaM use is common among yoga practitioners. YoBaM use seems to be associated with age, gender, ethnicity, region, marital status and psychological distress dimensions., (Copyright © 2020 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Chronic imaging of neuronal networks in vitro has provided fundamental insights into mechanisms underlying neuronal function. Current labeling and optical imaging methods, however, cannot be used for continuous and long-term recordings of the dynamics and evolution of neuronal networks, as fluorescent indicators can cause phototoxicity. Here, we introduce a versatile platform for label-free, comprehensive and detailed electrophysiological live-cell imaging of various neurogenic cells and tissues over extended time scales. We report on a dual-mode high-density microelectrode array, which can simultaneously record in (i) full-frame mode with 19,584 recording sites and (ii) high-signal-to-noise mode with 246 channels. We set out to demonstrate the capabilities of this platform with recordings from primary and iPSC-derived neuronal cultures and tissue preparations over several weeks, providing detailed morpho-electrical phenotypic parameters at subcellular, cellular and network level. Moreover, we develop reliable analysis tools, which drastically increase the throughput to infer axonal morphology and conduction speed.

When dense granular matter is sheared, the strain is often localized in shear bands. After some initial transient these shear bands become stationary. Here, we introduce a setup that periodically creates horizontally aligned shear bands which then migrate upward through the sample. Using x-ray radiography we demonstrate that this effect is caused by dilatancy, the reduction in volume fraction occurring in sheared dense granular media. Further on, we argue that these migrating shear bands are responsible for the previously reported periodic inflating and collapsing of the material.

Bottom-up synthetic biology has directed most efforts toward the construction of artificial compartmentalized systems that recreate living cell functions in their mechanical, morphological, or metabolic characteristics. However, bottom-up synthetic biology also offers great potential to study subcellular structures like organelles. Because of their intricate and complex structure, these key elements of eukaryotic life forms remain poorly understood. Here, the controlled assembly of lipid enclosed, organelle-like architectures is explored by droplet-based microfluidics. Three types of giant unilamellar vesicles (GUVs)-based synthetic organelles (SOs) functioning within natural living cells are procedured: (A) synthetic peroxisomes supporting cellular stress-management, mimicking an organelle innate to the host cell by using analogous enzymatic modules; (B) synthetic endoplasmic reticulum (ER) as intracellular light-responsive calcium stores involved in intercellular calcium signalling, mimicking an organelle innate to the host cell but utilizing a fundamentally different mechanism; and (C) synthetic magnetosomes providing eukaryotic cells with a magnetotactic sense, mimicking an organelle that is not natural to the host cell but transplanting its functionality from other branches of the phylogenetic tree. Microfluidic assembly of functional SOs paves the way for high-throughput generation of versatile intracellular structures implantable into living cells. This in-droplet SO design may support or expand cellular functionalities in translational nanomedicine., (© 2020 The Authors. Published by WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Carbon nanotube (CNT)-based field-effect transistors have demonstrated great potential for high-frequency (HF) analog transceiver electronics. Despite significant advancements, one of the remaining challenges is the optimization of the device architecture for obtaining the highest possible speed and linearity. While most studies so far have concentrated on symmetrical top gated FET devices, we report on the impact of the device architecture on their HF performance. Based on a wafer-level nanotechnology platform and device simulations, transistors with a buried gate having different widths and positions in the FET channel have been fabricated. Analysis of several FETs with nonsymmetrical gate electrode location in the channel revealed a speed increase of up to 18% measured by the external transit frequency f T and maximum frequency of oscillation f max . Although only randomly oriented CNTs with a density of 25 CNTs/μm and 280 nm long channels were used in this study, transit frequencies up to 14 GHz were obtained.

In contrast to molecular gases, granular gases are characterized by inelastic collisions and require therefore permanent driving to maintain a constant kinetic energy. The kinetic theory of granular gases describes how the average velocity of the particles decreases after the driving is shut off. Moreover, it predicts that the rescaled particle velocity distribution will approach a stationary state with overpopulated high-velocity tails as compared to the Maxwell-Boltzmann distribution. While this fundamental theoretical result was reproduced by numerical simulations, an experimental confirmation is still missing. Using a microgravity experiment that allows the spatially homogeneous excitation of spheres via magnetic fields, we confirm the theoretically predicted exponential decay of the tails of the velocity distribution.

Ecosystem service assessments rarely consider flows between distant regions. Hence, telecoupling effects such as conservation burdens in distant ecosystems are ignored. We identified service-providing species for two cultural ecosystem services (existence and bequest, and birdwatching) and two receiving, i.e. benefitting, regions (Germany, the Netherlands). We delineated and analysed sending, i.e. service-providing, regions on a global scale. The proportion of service-providing species with distant habitats was higher for birdwatching (Germany: 58.6%, Netherlands: 59.4%), than for existence and bequest (Germany: 49.3%, Netherlands: 57.1%). Hotspots of sending regions were predominantly situated in tropical and subtropical grasslands, savannas and shrublands and were significantly more threatened and poorer than the global mean. Hotspot protection levels for flows to Germany were higher than the global mean, and lower for the Dutch hotspots. Our findings increase understanding on how distant regions underpin ecosystem services and necessitate interregional assessment as well as conservation efforts.

The complexity of the transcriptome is governed by the intricate interplay of transcription, RNA processing, translocation, and decay. In eukaryotes, the removal of the 5'-RNA cap is essential for the initiation of RNA degradation. In addition to the canonical 5'-N7-methyl guanosine cap in eukaryotes, the ubiquitous redox cofactor nicotinamide adenine dinucleotide (NAD) was identified as a new 5'-RNA cap structure in prokaryotic and eukaryotic organisms. So far, two classes of NAD-RNA decapping enzymes have been identified, namely Nudix enzymes that liberate nicotinamide mononucleotide (NMN) and DXO-enzymes that remove the entire NAD cap. Herein, we introduce 8-(furan-2-yl)-substituted NAD-capped-RNA ( Fur NAD-RNA) as a new research tool for the identification and characterization of novel NAD-RNA decapping enzymes. These compounds are found to be suitable for various enzymatic reactions that result in the release of a fluorescence quencher, either nicotinamide (NAM) or nicotinamide mononucleotide (NMN), from the RNA which causes a fluorescence turn-on. Fur NAD-RNAs allow for real-time quantification of decapping activity, parallelization, high-throughput screening and identification of novel decapping enzymes in vitro. Using Fur NAD-RNAs, we discovered that the eukaryotic glycohydrolase CD38 processes NAD-capped RNA in vitro into ADP-ribose-modified-RNA and nicotinamide and therefore might act as a decapping enzyme in vivo. The existence of multiple pathways suggests that the decapping of NAD-RNA is an important and regulated process in eukaryotes.

The composition of the intestinal microbiota influences the outcome of enteric infections in human and mice. However, the role of specific members and their metabolites contributing to disease severity is largely unknown. Using isogenic mouse lines harboring distinct microbiota communities, we observed highly variable disease kinetics of enteric Citrobacter rodentium colonization after infection. Transfer of communities from susceptible and resistant mice into germ-free mice verified that the varying susceptibilities are determined by microbiota composition. The strongest differences in colonization were observed in the cecum and could be maintained in vitro by coculturing cecal bacteria with C. rodentium. Cohousing of animals as well as the transfer of cultivable bacteria from resistant to susceptible mice led to variable outcomes in the recipient mice. Microbiome analysis revealed that a higher abundance of butyrate-producing bacteria was associated with the resistant phenotype. Quantification of short-chain fatty acid (SCFA) levels before and after infection revealed increased concentrations of acetate, butyrate and propionate in mice with delayed colonization. Addition of physiological concentrations of butyrate, but not of acetate and/or propionate strongly impaired growth of C. rodentium in vitro. In vivo supplementation of susceptible, antibiotic-treated and germ-free mice with butyrate led to the same level of protection, notably only when cecal butyrate concentration reached a concentration higher than 50 nmol/mg indicating a critical threshold for protection. In the recent years, commensal-derived primary and secondary bacterial metabolites emerged as potent modulators of hosts susceptibility to infection. Our results provide evidence that variations in SCFA production in mice fed fibre-rich chow-based diets modulate susceptibility to colonization with Enterobacteriaceae not only in antibiotic-disturbed ecosystems but even in undisturbed microbial communities. These findings emphasise the need for microbiota normalization across laboratory mouse lines for infection experiments with the model-pathogen C. rodentium independent of investigations of diet and antibiotic usage., Competing Interests: The authors have declared that no competing interests exist.

Patterns of functional interactions across distributed brain regions are suggested to provide a scaffold for the conscious processing of information, with marked topological alterations observed in loss of consciousness. However, establishing a firm link between macro-scale brain network organisation and conscious cognition requires direct investigations into neuropsychologically-relevant architectural modifications across systematic reductions in consciousness. Here we assessed both global and regional disturbances to brain graphs in a group of healthy participants across baseline resting state fMRI as well as two distinct levels of propofol-induced sedation. We found a persistent modular architecture, yet significant reorganisation of brain hubs that formed parts of a wider rich-club collective. Furthermore, the reduction in the strength of rich-club connectivity was significantly associated with the participants' performance in a semantic judgment task, indicating the importance of this higher-order topological feature for conscious cognition. These results highlight a remarkable interplay between global and regional properties of brain functional interactions in supporting conscious cognition that is relevant to our understanding of clinical disorders of consciousness.

The discovery of methane (CH 4 ) accumulation in oxic marine and limnic waters has redefined the role of aquatic environments in the regional CH 4 cycle. Although CH 4 accumulation in oxic surface waters became apparent in recent years, the sources are still subject to controversial discussions. We present high-resolution in situ measurements of CH 4 concentration and its stable isotope composition in a stratified mesotrophic lake. We show that CH 4 accumulation in surface waters originates from a highly dynamic interplay between (oxic) CH 4 production and emission to the atmosphere. Laboratory incubations of different phytoplankton types and application of stable isotope techniques provide a first unambiguous evidence that major phytoplankton classes in Lake Stechlin per se produce CH 4 under oxic conditions. Combined field and lab results show that the photoautotroph community is an important driver for CH 4 production and its highly dynamic accumulation in oxic surface waters.

Reactive flows inside porous media play an important role in a number of geophysical and industrial processes. Here, we present three-dimensional experimental measurements on how precipitation and flow patterns change with the flow rate inside a model porous medium consisting of monodisperse glass beads. The sample is initially filled with an aqueous solution of sodium carbonate into which a solution of barium chloride is injected at a constant flow rate. Upon contact and reaction, the two reactants produce water-insoluble barium carbonate which precipitates onto the glass beads. This precipitate then modifies the flow morphology which in turn changes the spatial distribution of the precipitate. We discuss the influence of the flow rate on the morphology of the flow pattern and demonstrate that neither viscous fingering nor the Rayleigh-Taylor instability have any significant influence in our model system.

Biodiversity is suffering dramatic declines across the globe, threatening the ability of ecosystems to provide the services on which humanity depends. Mainstreaming biodiversity into the plans, strategies and policies of different economic sectors is key to reversing these declines. The importance of this mainstreaming is recognized by the Convention on Biological Diversity (CBD) and its Aichi targets. Individual countries can implement the goals of the CBD through their National Biodiversity Strategies and Action Plans (NBSAPs), which aim to, inter alia, support the mainstreaming of biodiversity into the policies of key economic sectors, such as agriculture, forestry and fisheries. This paper investigates the performance of countries at incorporating biodiversity mainstreaming into their post-2010 NBSAPs. We conduct a large-scale review of 144 NBSAPs against five criteria and calculate a national-level indicator for comparing levels of mainstreaming among countries. Our results show that developing countries, particularly those in Africa, have higher scores, indicating that they have a higher awareness of the importance of biodiversity mainstreaming. Developing nations were also more likely to involve a greater range of stakeholders in the NBSAP development process, whilst developed nations were less likely to give specific details about the monetary contributions of biodiversity to their economies. Overall, our findings suggest that biodiversity mainstreaming remains a challenge across much of the world, but that progress in some areas can provide direction and momentum in the future., (© 2019 The Authors.)

The intensity of a monochromatic X-ray beam decreases exponentially with the distance it has traveled inside a material; this behavior is commonly referred to as Beer-Lambert's law. Knowledge of the material-specific attenuation coefficient μ allows us to determine the thickness of a sample from the intensity decrease the beam has experienced. However, classical X-ray tubes emit a polychromatic bremsstrahlung-spectrum. And the attenuation coefficients of all materials depend on the photon energy: photons with high energy are attenuated less than photons with low energy. In consequence, the X-ray spectrum changes while traveling through the medium; due to the relative increase in high energy photons, this effect is called beam hardening. For this varying spectrum, the Beer-Lambert law only remains valid if μ is replaced by an effective attenuation coefficient μ eff which depends not only on the material but also on its thickness x and the details of the X-ray setup used. We present here a way to deduce μ eff (x) from a small number of auxiliary measurements using a phenomenological model. This model can then be used to determine an unknown material thickness or in the case of a granular media its volume fraction.

Förster theory describes electronic exciton energy migration in molecular assemblies as an incoherent hopping process between donor and acceptor molecules. The rate is expressed in terms of the overlap integral between donor fluorescence and acceptor absorption spectra. Typical time scales for systems like photosynthetic antennae are on the order of a few picoseconds. Prior to transfer, it is assumed that the initially excited donor molecule has equilibrated with respect to the local environment. However, upon excitation and during the equilibration phase, the state of the system needs to be described by the full density matrix, including coherences between donor and acceptor states. While being intuitively clear, addressing this regime experimentally has been a challenge until the recently reported advances in fluorescence detected two-dimensional spectroscopy. Here, we demonstrate using fourth order perturbation theory the conditions for the presence of donor-acceptor coherence induced cross-peaks at zero waiting time between the first and the second pair of pulses. The approach is illustrated for a heterodimer model which facilitates an analytical solution.

Our understanding of the structural features of foams and emulsions has advanced significantly over the last 20 years. However, with a search for "super-stable" liquid dispersions, foam and emulsion science employs increasingly complex formulations which create solid-like visco-elastic layers at the bubble/drop surfaces. These lead to elastic, adhesive and frictional forces between bubbles/drops, impacting strongly how they pack and deform against each other, asking for an adaptation of the currently available structural description. The possibility to modify systematically the interfacial properties makes these dispersions ideal systems for the exploration of soft granular materials with complex interactions. We present here a first systematic analysis of the structural features of such a system using a model silicone emulsion containing millimetre-sized polyethylene glycol drops (PEG). Solid-like drop surfaces are obtained by polymeric cross-linking reactions at the PEG-silicone interface. Using a novel droplet-micromanipulator, we highlight the presence of elastic, adhesive and frictional interactions between two drops. We then provide for the first time a full tomographic analysis of the structural features of these emulsions. An in-depth analysis of the angle of repose, local volume fraction distributions, pair correlation functions and the drop deformations for different skin formulations allow us to put in evidence the striking difference with "ordinary" emulsions having fluid-like drop surfaces. While strong analogies with frictional hard-sphere systems can be drawn, these systems display a set of unique features due to the high deformability of the drops which await systematic exploration.

In this manuscript, we introduce a simple, off-the-shelf approach for the on-demand creation of giant unilamellar vesicles (GUVs) or multicompartment synthetic cell model systems in a high-throughput manner. To achieve this, we use microfluidics to encapsulate small unilamellar vesicles in block-copolymer surfactant-stabilized water-in-oil droplets. By tuning the charge of the inner droplet interface, adsorption of lipids can be either inhibited, leading to multicompartment systems, or induced, leading to the formation of droplet-stabilized GUVs. To control the charge density, we formed droplets using different molar ratios of an uncharged PEG-based fluorosurfactant and a negatively-charged PFPE carboxylic acid fluorosurfactant (Krytox). We systematically studied the transition from a multicompartment system to 3D-supported lipid bilayers as a function of lipid charge and Krytox concentration using confocal fluorescence microscopy, cryo-scanning electron microscopy and interfacial tension measurements. Moreover, we demonstrate a simple method to release GUVs from the surfactant shell and the oil phase into a physiological buffer - providing a remarkably high-yield approach for GUV formation. This widely applicable microfluidics-based technology will increase the scope of GUVs as adaptable cell-like compartments in bottom-up synthetic biology applications and beyond.

The mechanisms underlying triboelectric charging have a stochastic nature. We investigate how this randomness affects the distributions of charges generated on granular particles during either a single or many collisions. The charge distributions we find in our experiments are more heavy-tailed than normal distributions with an exponential decay of the probability, they are asymmetric, and exhibit charges of both signs. Moreover, we find a linear correlation between the width and mean of these distributions. We rationalize these findings with a model for triboelectric charging which combines stochastic charge separation during contact and stochastic charge recombination after separation of the surfaces. Our results further imply that subsequent charging events are not statistically independent.

Bacterial photosynthesis features robust and adaptable energy-harvesting processes in which light-harvesting proteins play a crucial role. The peripheral light-harvesting complex of the purple bacterium Allochromatium vinosum is particularly distinct, featuring a double peak structure in its B800 absorption band. Two hypotheses-not necessarily mutually exclusive-concerning the origin of this splitting have been proposed; either two distinct B800 bacteriochlorophyll site energies are involved, or an excitonic dimerization of bacteriochlorophylls within the B800 ring takes place. Through the use of two-dimensional electronic spectroscopy, we present unambiguous evidence that excitonic interaction shapes the split band. We further identify and characterize all of the energy transfer pathways within this complex by using a global kinetic fitting procedure. Our approach demonstrates how the combination of two-dimensional spectral resolution and self-consistent fitting allows for extraction of information on light-harvesting processes, which would otherwise be inaccessible due to signal congestion.

We present an experiment on crystallization of packings of macroscopic granular spheres. This system is often considered to be a model for thermally driven atomic or colloidal systems. Cyclically shearing a packing of frictional spheres, we observe a first order phase transition from a disordered to an ordered state. The ordered state consists of crystallites of mixed fcc and hcp symmetry that coexist with the amorphous bulk. The transition, initiated by homogeneous nucleation, overcomes a barrier at 64.5% volume fraction. Nucleation consists predominantly of the dissolving of small nuclei and the growth of nuclei that have reached a critical size of about ten spheres.