Accessing the Next Generation of Synthetic Mussel‐Glue Polymers via Mussel‐Inspired Polymerization

The formation of cysteinyldopa as biogenic connectivity in proteins is used to inspire a chemical pathway toward mussel-adhesive mimics. The mussel-inspired polymerization (MIPoly) exploits the chemically diverse family of bisphenol monomers that is oxidizable with 2-iodoxybenzoic acid to give bisquinones. Those react at room temperature with dithiols in Michael-type polyadditions, which leads to polymers with thiol–catechol connectivities (TCC). A set of TCC polymers proved adhesive behavior even on challenging poly(propylene) substrates, where they compete with commercial epoxy resins in dry adhesive strength. MIPoly promises facile scale up and exhibits high modularity to tailor adhesives, as proven on a small library where one candidate showed wet adhesion on aluminum substrates in both water and sea water models.Verband der Chemischen Industrie http://dx.doi.org/10.13039/100007215Deutsche Forschungsgemeinschaft http://dx.doi.org/10.13039/501100001659Peer Reviewe

Electrical phenomena during CO2–rock interaction under reservoir conditions : experimental investigations and their implications for electromagnetic monitoring applications

Geophysical methods are essential for exploration and monitoring of subsurface formations, e.g. in carbon dioxide sequestration or enhanced geothermal energy. One of the keys to their successful application is the knowledge of how the measured physical quantities are related to the desired reservoir parameters. The work presented in this thesis shows that the presence of carbon dioxide (CO2) in pore space gives rise to multiple processes all of which contribute to the electrical rock conductivity variation. Basically, three mechanisms take place: (1) CO2 partially replaces the pore water, which is equivalent to a decrease in water saturation. (2) CO2 chemically interacts with the pore water by dissolution and dissociation. These processes change both the chemical composition and the pH of the pore filling fluid. (3) The low-pH environment can give rise to mineral dissolution and/or precipitation processes and changes the properties of the grain-water interface. Investigations on the pore water phase show that the reactive nature of CO2 in all physical states significantly acts on the electrical conductivity of saline pore waters. The physico-chemical interaction appears in different manifestations depending mainly on the pore water composition (salinity, ion types) but also on both temperature and pressure. The complex behaviour includes a low- and a high-salinity regime originating from the conductivity increasing effect of CO2 dissociation, which is opposed by the conductivity decreasing effect of reduced ion activity caused by the enhanced mutual impediment of all solutes. These results are fundamental since the properties of the water phase significantly act on all conduction mechanisms in porous media. In order to predict the variation of pore water conductivity, both a semi-analytical formulation and an empirical relationship for correcting the pore water conductivity, which depends on salinity, pressure and temperature, are derived. The central part of the laboratory experiments covers the spectral complex conductivity of water-bearing sand during exposure to and flow-through by CO2 at pressures up to 30MPa and temperatures up to 80°C. It is shown that the impact of CO2 on the real part of conductivity of a clean quartz sand is dominated by the low- and high-salinity regime of the pore water. The obtained data further show that chemical interaction causes a reduction of interface conductivity, which could be related to the low pH in the acidic environment. This effect is described by a correction term, which is a constant value as a first approximation. When the impact of CO2 is taken into account, a correct reconstruction of fluid saturation from electrical measurements is possible. In addition, changes of the inner surface area, which are related to mineral dissolution or precipitation processes, can be quantified. Both the knowledge gained from the laboratory experiments and a new workflow for the description and incorporation of geological geometry models enable realistic finite element simulations. Those were conducted for three different electromagnetic methods applied in the geological scenario of a fictitious carbon dioxide sequestration site. The results show that electromagnetic methods can play an important role in monitoring CO2 sequestration. Compared to other geophysical methods, electromagnetic techniques are generally very sensitive to pore fluids. The proper configuration of sources and receivers for a suitable electromagnetic method that generates the appropriate current systems is essential. Its reactive nature causes CO2 to interact with a water-bearing porous rock in a much more complex manner than non-reactive gases. Without knowledge of the specific interactions between CO2 and rock, a determination of saturation and, consequently, a successful monitoring are possible only to a limited extend. The presented work provides fundamental laboratory investigations for the understanding of the electrical properties of rocks when the reactive gas CO2 enters the rock-water system. All laboratory results are put in the context of potential monitoring applications. The transfer from petrophysical investigations to the planning of an operational monitoring design by means of close-to-reality 3D FE simulations is accomplished

Implementing Zn2+ ion and pH-value control into artificial mussel glue proteins by abstracting a His-rich domain from preCollagen

A His-rich domain of preCollagen-D found in byssal threads is derivatized with Cys and Dopa flanks to allow for mussel-inspired polymerization. Artificial mussel glue proteins are accessed that combine cysteinyldopa for adhesion with sequences for pH or Zn2+ induced β-sheet formation. The artificial constructs show strong adsorption to Al2O3, the resulting coatings tolerate hypersaline conditions and cohesion is improved by activating the β-sheet formation, that enhances E-modulus up to 60%.Peer Reviewe

Organic transformation of lignin into mussel-inspired glues: next-generation 2K adhesive for setting corals under saltwater

The 2-methoxyphenol units (G-units) in lignin are modified by demethylation and oxidation to provide the activated lignin as one part of an advanced biobased two-component (2K) adhesive system, which exhibits promising shear strengths in dry and underwater applications. The activation of lignin is straightforward and generates quinones via demethylation and periodate oxidation. These act as Michael acceptors and react smoothly with multi-thiol-star polymers to yield thiol-catechol connectivities (TCCs). The mussel-inspired material platform acts as a very robust and versatile adhesive, combining low-cost and readily available lignin with multi-thiols to achieve outstanding adhesion strengths of up to 15 MPa in dry application. In particular, the 2K system is compatible with the marine biological environment and shows no acute toxicity to sensitive organisms such as fish eggs. Thus, one possible application of this material could be an adhesive for setting temperature-resistant corals in damaged reefs.Peer Reviewe

A Systematic Nomenclature for the Drosophila Ventral Nervous System

Insect nervous systems are proven and powerful model systems for neuroscience research with wide relevance in biology and medicine. However, descriptions of insect brains have suffered from a lack of a complete and uniform nomenclature. Recognising this problem the Insect Brain Name Working Group produced the first agreed hierarchical nomenclature system for the adult insect brain, using Drosophila melanogaster as the reference framework, with other insect taxa considered to ensure greater consistency and expandability (Ito et al., 2014). Ito et al. (2014) purposely focused on the gnathal regions that account for approximately 50% of the adult CNS. We extend this nomenclature system to the sub-gnathal regions of the adult Drosophila nervous system to provide a nomenclature of the so-called ventral nervous system (VNS), which includes the thoracic and abdominal neuromeres that was not included in the original work and contains the neurons that play critical roles underpinning most fly behaviours

A Systematic Nomenclature for the Drosophila Ventral Nervous System

Insect nervous systems are proven and powerful model systems for neuroscience research with wide relevance in biology and medicine. However, descriptions of insect brains have suffered from a lack of a complete and uniform nomenclature. Recognising this problem the Insect Brain Name Working Group produced the first agreed hierarchical nomenclature system for the adult insect brain, using Drosophila melanogaster as the reference framework, with other insect taxa considered to ensure greater consistency and expandability (Ito et al., 2014). Ito et al. (2014) purposely focused on the gnathal regions that account for approximately 50% of the adult CNS. We extend this nomenclature system to the sub-gnathal regions of the adult Drosophila nervous system to provide a nomenclature of the so-called ventral nervous system (VNS), which includes the thoracic and abdominal neuromeres that was not included in the original work and contains the neurons that play critical roles underpinning most fly behaviours

Mammals show faster recovery from capture and tagging in human-disturbed landscapes

Wildlife tagging provides critical insights into animal movement ecology, physiology, and behavior amid global ecosystem changes. However, the stress induced by capture, handling, and tagging can impact post-release locomotion and activity and, consequently, the interpretation of study results. Here, we analyze post-tagging effects on 1585 individuals of 42 terrestrial mammal species using collar-collected GPS and accelerometer data. Species-specific displacements and overall dynamic body acceleration, as a proxy for activity, were assessed over 20 days post-release to quantify disturbance intensity, recovery duration, and speed. Differences were evaluated, considering species-specific traits and the human footprint of the study region. Over 70% of the analyzed species exhibited significant behavioral changes following collaring events. Herbivores traveled farther with variable activity reactions, while omnivores and carnivores were initially less active and mobile. Recovery duration proved brief, with alterations diminishing within 4–7 tracking days for most species. Herbivores, particularly males, showed quicker displacement recovery (4 days) but slower activity recovery (7 days). Individuals in high human footprint areas displayed faster recovery, indicating adaptation to human disturbance. Our findings emphasize the necessity of extending tracking periods beyond 1 week and particular caution in remote study areas or herbivore-focused research, specifically in smaller mammals

Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

Abstract Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries

Atlasgeneration und Atlasanwendungen

Modern neuroanatomy requires quantification of neural structures, i. e. neurons, circuits and brain parts. The increased computational power that has become available during recent years makes electronic knowledge bases possible, which can serve as common platforms for the incorporation of anatomical and physiological data. In this study a standardized neuroanatomical atlas for the ventral nerve cord of the genetic model system, Drosophila melanogaster was generated. By testing the quality of the standard it could be confirmed that the neuropil standard can serve as real average of wild-type Drosophila. A standardized staining protocol with a commercially available antibody ensures that the standard is applicable for any user. Standard generation was based on the entire neuropil structure and internal neuropil boundaries could be defined. With a global thresholding criterion user interaction for the segmentation process could be minimized and therefore, offers an easy and non time-consuming way for standard registration. The standard will be made available on the web together with a detail protocol for the histological methods, the segmentation, and the registration process. Ganglionic cortex, tracts, and commissures were registered into the standard to define additional landmarks. The feasibility for standard registration for managing gene expression data was tested for several GAL4 lines. Theoretically any structure that was counterstained with the neuropil marker can be registered into the standard. However, standard registration was not useful for every expression pattern to display similarities or differences between GAL4 lines. Registration of anatomical structures derived from individual samples into the reference space yielded in a good overlay and allowed for defining of sub-neuropils within the standard. In a new approach it could be shown that these defined sub-regions can be applied onto individual samples by backwards application of the standard. This allowed for comparative studies of ventral nerve cord neuropils, i.e. transmitter compositions of neuropil regions with defined functions. Spatial relationships of registered structures can be investigated within the common reference space. An overlap of axonal and dendritic projections could indicate connectivity of identified neurons stained in individual samples. With the identification of the putative monosynaptic connection of sensory neurons and the flight motoneuron of Drosophila the feasibility of standard registration can now be tested for revealing synaptic connectivity.Eine Quantifizierung von neuronalen Strukturen wie Nervenzellen, Netzwerke und Gehirnteile ist fuer moderne Neuroanatomie von grosser Bedeutung. Mit zunehmender Rechnerleistung, die in den letzten Jahren verfuegbar wurde, koennen elektronische Datenbanken generiert werden. Diese dienen als oeffentliche Plattformen in die neuroanatomische und physiologische Daten integriert werden koennen. In der vorliegenden Arbeit wurde ein standardisierter neuroanatomischer Atlas fuer das ventrale Nervensystem von adulten Drosophila melanogaster generiert. Mit der Ueberpruefung der Qualitaet des Standards konnte bestaetigt werden, dass dieser einen Durchschnitt von wildtypischen Drosophila bildet. Durch die Anwendung eines standardisierten Faerbeprotokolls mit einem kommerziell erwerblichen Antikoerper kann dieser Standard von jedem Nutzer angewendet werden. Die gesamte Neuropilstruktur des ventralen Nervensystems ist in diesem Standard enthalten und interne Neuropilgrenzen wurden integriert. Der Segmentierungsprozess der Neuropilstruktur basierte auf einem globalen Schwellenwert, dieses fuehrte zu einer einfachen und zeitsparenden Anwendung. Der Standard wird auf einer Internetseite zusammen mit einem detailierten Protokoll fuer die histologischen Methoden, der Segmentierung und des Registrierungsvorgangs veroeffentlicht werden. Die Ganglionrinde, Trakte und Kommissuren wurden als zusaetzliche Landmarken in den Standard integriert. Eine Anwendung des Standards fuer die Verwaltung von Genexpressionsdaten wurde mit der Integration von verschiedenen GAL4 Linien getestet. Jede Struktur, die mit einem Neuropilmarker gegengefaerbt wird, kann theoretischer weise in den Standard registriert werden. Fuer einige der getesteten GAL4 Linien war eine Registrierung in den Standard jedoch nicht sinnvoll, um Aehnlichkeiten oder Unterschiede zwischen den Expressionsmustern verschiedener Linien festzustellen. Mit der Registrierung von anatomischen Strukturen aus individuellen Tieren und dem anschliessenden Uebereinanderlagern dieser Strukturen im Standard konnten interne Einzelneuropile abgegrenzt werden. Diese zuvor definierten Unterstrukturen konnten in Einzelpraeparaten definiert werden, indem der Standard auf diese Praeparate registriert wurde. Mit dieser neuen Methode koennen Informationen ueber die Feinstruktur von Neuropilregionen untersucht werden und zwischen individuellen Praeparaten verglichen werden. Die Lage von registrierten Strukturen zueinander kann innerhalb des gemeinsamen Referenzatlasses ueberprueft werden. Eine Ueberlagerung von Axonen und Dendriten von registrierten Neuronen kann auf eine moegliche Konnektivitaet zwischen beiden Komponenten hindeuten. Mit der Identifizierung einer monosynaptischen Verbindung von sensorischen Neuronen und dem Flugmotoneuron in Drosophila, kann nun die Anwendung des Standards fuer die Identifizierung solcher Kontakte durch Standardregistrierung getestet werden