@article{18587, abstract = {Many scientific breakthroughs have depended on animal research, yet the ethical concerns surrounding the use of animals in experimentation have long prompted discussions about humane treatment and responsible scientific practice. First articulated by Russell and Burch, the 3Rs Principles of Replacement, Reduction, and Refinement have gained widespread recognition as basic guidelines for animal research. Over time, the 3Rs have transcended the research community, influencing policy decisions, animal welfare advocacy and public perception of animal experimentation. Despite their broad acceptance, interpretations of the 3Rs vary substantially, shaping statutory frameworks at various levels, with both technical and practical impacts.}, author = {Lauwereyns, Jan and Bajramovic, Jeffrey and Bert, Bettina and Camenzind, Samuel and De Kock, Joery and Elezović, Alisa and Erden, Sevilay and Gonzalez-Uarquin, Fernando and Ulman, Yesim Isil and Hoffmann, Orsolya Ivett and Kitsara, Maria and Kostomitsopoulos, Nikolaos and Neuhaus, Winfried and Petit-Demouliere, Benoit and Pollo, Simone and Riso, Brígida and Schober, Sophie and Sotiropoulos, Athanassia and Thomas, Aurélie and Vitale, Augusto and Wilflingseder, Doris and Ahluwalia, Arti}, issn = {1548-4475}, journal = {Lab Animal}, pages = {347--350}, publisher = {Springer Nature}, title = {{Toward a common interpretation of the 3Rs principles in animal research}}, doi = {10.1038/s41684-024-01476-2}, volume = {53}, year = {2024}, } @article{18310, author = {Kitsara, Maria and Smajlhodžić-Deljo, Merima and Gurbeta Pokvic, Lejla and Bert, Bettina and Bubalo, Nataliia and Erden, Sevilay and Franco, Nuno Henrique and Chirico, Giuseppe and Gómez Raja, Jonathan and Gonzalez-Uarquin, Fernando and Lang, Annemarie and Linklater, Nicole and Mojsova, Sandra and Olsson, I. Anna S. and Sandvig, Ioanna and Schaffert, Alexandra and Schmit, Marthe and Schober, Sophie and Sevastre, Bogdan and Wilflingseder, Doris and Ahluwalia, Arti and Neuhaus, Winfried}, issn = {2632-3559}, journal = {Alternatives to Laboratory Animals}, number = {6}, pages = {326--333}, publisher = {SAGE Publications}, title = {{Introducing the COST action ‘Improving the Quality of Biomedical Science with 3Rs Concepts’ (IMPROVE)}}, doi = {10.1177/02611929241286024}, volume = {52}, year = {2024}, } @article{14846, abstract = {Contraction and flow of the actin cell cortex have emerged as a common principle by which cells reorganize their cytoplasm and take shape. However, how these cortical flows interact with adjacent cytoplasmic components, changing their form and localization, and how this affects cytoplasmic organization and cell shape remains unclear. Here we show that in ascidian oocytes, the cooperative activities of cortical actomyosin flows and deformation of the adjacent mitochondria-rich myoplasm drive oocyte cytoplasmic reorganization and shape changes following fertilization. We show that vegetal-directed cortical actomyosin flows, established upon oocyte fertilization, lead to both the accumulation of cortical actin at the vegetal pole of the zygote and compression and local buckling of the adjacent elastic solid-like myoplasm layer due to friction forces generated at their interface. Once cortical flows have ceased, the multiple myoplasm buckles resolve into one larger buckle, which again drives the formation of the contraction pole—a protuberance of the zygote’s vegetal pole where maternal mRNAs accumulate. Thus, our findings reveal a mechanism where cortical actomyosin network flows determine cytoplasmic reorganization and cell shape by deforming adjacent cytoplasmic components through friction forces.}, author = {Caballero Mancebo, Silvia and Shinde, Rushikesh and Bolger-Munro, Madison and Peruzzo, Matilda and Szep, Gregory and Steccari, Irene and Labrousse Arias, David and Zheden, Vanessa and Merrin, Jack and Callan-Jones, Andrew and Voituriez, Raphaël and Heisenberg, Carl-Philipp J}, issn = {1745-2481}, journal = {Nature Physics}, pages = {310--321}, publisher = {Springer Nature}, title = {{Friction forces determine cytoplasmic reorganization and shape changes of ascidian oocytes upon fertilization}}, doi = {10.1038/s41567-023-02302-1}, volume = {20}, year = {2024}, } @article{14795, abstract = {Metazoan development relies on the formation and remodeling of cell-cell contacts. Dynamic reorganization of adhesion receptors and the actomyosin cell cortex in space and time plays a central role in cell-cell contact formation and maturation. Nevertheless, how this process is mechanistically achieved when new contacts are formed remains unclear. Here, by building a biomimetic assay composed of progenitor cells adhering to supported lipid bilayers functionalized with E-cadherin ectodomains, we show that cortical F-actin flows, driven by the depletion of myosin-2 at the cell contact center, mediate the dynamic reorganization of adhesion receptors and cell cortex at the contact. E-cadherin-dependent downregulation of the small GTPase RhoA at the forming contact leads to both a depletion of myosin-2 and a decrease of F-actin at the contact center. At the contact rim, in contrast, myosin-2 becomes enriched by the retraction of bleb-like protrusions, resulting in a cortical tension gradient from the contact rim to its center. This tension gradient, in turn, triggers centrifugal F-actin flows, leading to further accumulation of F-actin at the contact rim and the progressive redistribution of E-cadherin from the contact center to the rim. Eventually, this combination of actomyosin downregulation and flows at the contact determines the characteristic molecular organization, with E-cadherin and F-actin accumulating at the contact rim, where they are needed to mechanically link the contractile cortices of the adhering cells.}, author = {Arslan, Feyza N and Hannezo, Edouard B and Merrin, Jack and Loose, Martin and Heisenberg, Carl-Philipp J}, issn = {1879-0445}, journal = {Current Biology}, number = {1}, pages = {171--182.e8}, publisher = {Elsevier}, title = {{Adhesion-induced cortical flows pattern E-cadherin-mediated cell contacts}}, doi = {10.1016/j.cub.2023.11.067}, volume = {34}, year = {2024}, } @article{15048, abstract = {Embryogenesis results from the coordinated activities of different signaling pathways controlling cell fate specification and morphogenesis. In vertebrate gastrulation, both Nodal and BMP signaling play key roles in germ layer specification and morphogenesis, yet their interplay to coordinate embryo patterning with morphogenesis is still insufficiently understood. Here, we took a reductionist approach using zebrafish embryonic explants to study the coordination of Nodal and BMP signaling for embryo patterning and morphogenesis. We show that Nodal signaling triggers explant elongation by inducing mesendodermal progenitors but also suppressing BMP signaling activity at the site of mesendoderm induction. Consistent with this, ectopic BMP signaling in the mesendoderm blocks cell alignment and oriented mesendoderm intercalations, key processes during explant elongation. Translating these ex vivo observations to the intact embryo showed that, similar to explants, Nodal signaling suppresses the effect of BMP signaling on cell intercalations in the dorsal domain, thus allowing robust embryonic axis elongation. These findings suggest a dual function of Nodal signaling in embryonic axis elongation by both inducing mesendoderm and suppressing BMP effects in the dorsal portion of the mesendoderm.}, author = {Schauer, Alexandra and Pranjic-Ferscha, Kornelija and Hauschild, Robert and Heisenberg, Carl-Philipp J}, issn = {1477-9129}, journal = {Development}, number = {4}, pages = {1--18}, publisher = {Company of Biologists}, title = {{Robust axis elongation by Nodal-dependent restriction of BMP signaling}}, doi = {10.1242/dev.202316}, volume = {151}, year = {2024}, } @misc{14926, author = {Hauschild, Robert}, publisher = {Institute of Science and Technology Austria}, title = {{Matlab script for analysis of clone dispersal}}, doi = {10.15479/AT:ISTA:14926}, year = {2024}, } @article{17885, abstract = {The formation of new ribosomes is tightly coordinated with cell growth and proliferation. In eukaryotes, the correct assembly of all ribosomal proteins and RNAs follows an intricate scheme of maturation and rearrangement steps across three cellular compartments: the nucleolus, nucleoplasm, and cytoplasm. We demonstrate that usnic acid, a lichen secondary metabolite, inhibits the maturation of the large ribosomal subunit in yeast. We combine biochemical characterization of pre-ribosomal particles with a quantitative single-particle cryo-EM approach to monitor changes in nucleolar particle populations upon drug treatment. Usnic acid rapidly blocks the transition from nucleolar state B to C of Nsa1-associated pre-ribosomes, depleting key maturation factors such as Dbp10 and hindering pre-rRNA processing. This primary nucleolar block rapidly rebounds on earlier stages of the pathway which highlights the regulatory linkages between different steps. In summary, we provide an in-depth characterization of the effect of usnic acid on ribosome biogenesis, which may have implications for its reported anti-cancer activities.}, author = {Kofler, Lisa and Grundmann, Lorenz and Gerhalter, Magdalena and Prattes, Michael and Merl-Pham, Juliane and Zisser, Gertrude and Grishkovskaya, Irina and Hodirnau, Victor-Valentin and Vareka, Martin and Breinbauer, Rolf and Hauck, Stefanie M. and Haselbach, David and Bergler, Helmut}, issn = {2041-1723}, journal = {Nature Communications}, publisher = {Springer Nature}, title = {{The novel ribosome biogenesis inhibitor usnic acid blocks nucleolar pre-60S maturation}}, doi = {10.1038/s41467-024-51754-3}, volume = {15}, year = {2024}, } @article{17284, abstract = {Platelet homeostasis is essential for vascular integrity and immune defence1,2. Although the process of platelet formation by fragmenting megakaryocytes (MKs; thrombopoiesis) has been extensively studied, the cellular and molecular mechanisms required to constantly replenish the pool of MKs by their progenitor cells (megakaryopoiesis) remains unclear3,4. Here we use intravital imaging to track the cellular dynamics of megakaryopoiesis over days. We identify plasmacytoid dendritic cells (pDCs) as homeostatic sensors that monitor the bone marrow for apoptotic MKs and deliver IFNα to the MK niche triggering local on-demand proliferation and maturation of MK progenitors. This pDC-dependent feedback loop is crucial for MK and platelet homeostasis at steady state and under stress. pDCs are best known for their ability to function as vigilant detectors of viral infection5. We show that virus-induced activation of pDCs interferes with their function as homeostatic sensors of megakaryopoiesis. Consequently, activation of pDCs by SARS-CoV-2 leads to excessive megakaryopoiesis. Together, we identify a pDC-dependent homeostatic circuit that involves innate immune sensing and demand-adapted release of inflammatory mediators to maintain homeostasis of the megakaryocytic lineage.}, author = {Gärtner, Florian R and Ishikawa-Ankerhold, Hellen and Stutte, Susanne and Fu, Wenwen and Weitz, Jutta and Dueck, Anne and Nelakuditi, Bhavishya and Fumagalli, Valeria and Van Den Heuvel, Dominic and Belz, Larissa and Sobirova, Gulnoza and Zhang, Zhe and Titova, Anna and Navarro, Alejandro Martinez and Pekayvaz, Kami and Lorenz, Michael and Von Baumgarten, Louisa and Kranich, Jan and Straub, Tobias and Popper, Bastian and Zheden, Vanessa and Kaufmann, Walter and Guo, Chenglong and Piontek, Guido and Von Stillfried, Saskia and Boor, Peter and Colonna, Marco and Clauß, Sebastian and Schulz, Christian and Brocker, Thomas and Walzog, Barbara and Scheiermann, Christoph and Aird, William C. and Nerlov, Claus and Stark, Konstantin and Petzold, Tobias and Engelhardt, Stefan and Sixt, Michael K and Hauschild, Robert and Rudelius, Martina and Oostendorp, Robert A.J. and Iannacone, Matteo and Heinig, Matthias and Massberg, Steffen}, issn = {1476-4687}, journal = {Nature}, pages = {645--653}, publisher = {Springer Nature}, title = {{Plasmacytoid dendritic cells control homeostasis of megakaryopoiesis}}, doi = {10.1038/s41586-024-07671-y}, volume = {631}, year = {2024}, } @article{18920, abstract = {The globally distributed marine alga Emiliania huxleyi has cooling effect on the Earth’s climate. The population density of E. huxleyi is restricted by Nucleocytoviricota viruses, including E. huxleyi virus 201 (EhV-201). Despite the impact of E. huxleyi viruses on the climate, there is limited information about their structure and replication. Here, we show that the dsDNA genome inside the EhV-201 virion is protected by an inner membrane, capsid, and outer membrane. EhV-201 virions infect E. huxleyi by using fivefold vertices to bind to and fuse the virus’ inner membrane with the cell plasma membrane. Progeny virions assemble in the cytoplasm at the surface of endoplasmic reticulum–derived membrane segments. Genome packaging initiates synchronously with the capsid assembly and completes through an aperture in the forming capsid. The genome-filled capsids acquire an outer membrane by budding into intracellular vesicles. EhV-201 infection induces a loss of surface protective layers from E. huxleyi cells, which enables the continuous release of virions by exocytosis.}, author = {Homola, Miroslav and Büttner, Renate Carina and Füzik, Tibor and Křepelka, Pavel and Holbová, Radka and Nováček, Jiří and Chaillet, Marten L. and Žák, Jakub and Grybchuk, Danyil and Förster, Friedrich and Wilson, William H. and Schroeder, Declan C. and Plevka, Pavel}, issn = {2375-2548}, journal = {Science Advances}, number = {15}, publisher = {American Association for the Advancement of Science}, title = {{Structure and replication cycle of a virus infecting climate-modulating alga Emiliania huxleyi}}, doi = {10.1126/sciadv.adk1954}, volume = {10}, year = {2024}, } @inbook{18052, abstract = {Sodium dodecyl sulfate-digested freeze-fracture replica labeling (SDS-FRL) is an electron microscope (EM) sample preparation technique which allows for high-resolution visualization of membrane proteins with high sensitivity. However, image acquisition of specific replica profiles such as synapses in a large field of EM view needs a valid experience and a long time for manual searching. Here, we describe how to utilize deep learning for automatizing image acquisition of specific profiles of interest in replica samples. This protocol facilitates the labor-intensive collection of EM images, in particular for rare profiles. We provide instructions for using SerialEM image acquisition software in conjunction with object detection by our newly developed deep learning software DarEM, to automatically acquire tilt series of all synapses in a selected region. We then show how to perform a mostly automated analysis of gold particle labeling in the acquired images by utilizing Darea software.}, author = {Kleindienst, David and Costanzo, Tommaso and Shigemoto, Ryuichi}, booktitle = {New Aspects in Analyzing the Synaptic Organization of the Brain}, editor = {Lübke, Joachim H.R. and Rollenhagen, Astrid}, isbn = {9781071640180}, issn = {1940-6045}, pages = {123--137}, publisher = {Springer Nature}, title = {{Automated Imaging and Analysis of Synapses in Freeze-Fracture Replica Samples with Deep Learning}}, doi = {10.1007/978-1-0716-4019-7_8}, year = {2024}, } @misc{23025, abstract = {The globally distributed marine alga Emiliania huxleyi produces reflective calcite disks (coccoliths) that increase the albedo of ocean water and thus reduce the heat absorption in the ocean, which cools the Earth’s climate. The population density of E. huxleyi is restricted by Nucleocytoviricota viruses, including E. huxleyi virus 201 (EhV-201). Despite the impact of E. huxleyi viruses on the climate, there is limited information about their structure and replication. Here we show that the dsDNA genome inside the EhV-201 virion is protected by an inner membrane, capsid, and outer membrane decorated with numerous transmembrane proteins. The virions are prone to deformation, and parts of their capsids deviate from the icosahedral arrangement. EhV-201 virions infect E. huxleyi by using their fivefold vertex to bind to a host cell and fuse the virus’s inner membrane with the plasma membrane. Whereas the replication of EhV-201 probably occurs in the nucleus, virions assemble in the cytoplasm at the surface of endoplasmic reticulum-derived membrane segments. Genome packaging initiates synchronously with the capsid assembly and completes through an aperture in the forming capsid. Upon the completion of genome packaging, the capsids change conformation, which enables them to acquire an outer membrane by budding into intracellular vesicles. EhV-201 infection induces a loss of surface protective layers from E. huxleyi cells, which allows the continuous release of virions by exocytosis. Our results provide insight into how EhVs bypass the surface protective layers of E. huxleyi and exploit the organelles of an infected cell for progeny assembly.}, author = {Homola, Miroslav and Büttner, Carina and Füzik, Tibor and Krepelka, Pavel and Holbová, Radka and Chaillet, Marten and Nováček, Jiří and Förster, Friedrich and Wilson, William and Schroeder, Declan and Plevka, Pavel}, publisher = {Dryad}, title = {{Data: Structure and replication cycle of a virus infecting climate-modulating alga Emiliania huxleyi}}, doi = {10.5061/dryad.p5hqbzkw0}, year = {2024}, } @article{15146, abstract = {The extracellular matrix (ECM) serves as a scaffold for cells and plays an essential role in regulating numerous cellular processes, including cell migration and proliferation. Due to limitations in specimen preparation for conventional room-temperature electron microscopy, we lack structural knowledge on how ECM components are secreted, remodeled, and interact with surrounding cells. We have developed a 3D-ECM platform compatible with sample thinning by cryo-focused ion beam milling, the lift-out extraction procedure, and cryo-electron tomography. Our workflow implements cell-derived matrices (CDMs) grown on EM grids, resulting in a versatile tool closely mimicking ECM environments. This allows us to visualize ECM for the first time in its hydrated, native context. Our data reveal an intricate network of extracellular fibers, their positioning relative to matrix-secreting cells, and previously unresolved structural entities. Our workflow and results add to the structural atlas of the ECM, providing novel insights into its secretion and assembly.}, author = {Zens, Bettina and Fäßler, Florian and Hansen, Jesse and Hauschild, Robert and Datler, Julia and Hodirnau, Victor-Valentin and Zheden, Vanessa and Alanko, Jonna H and Sixt, Michael K and Schur, Florian KM}, issn = {1540-8140}, journal = {Journal of Cell Biology}, number = {6}, publisher = {Rockefeller University Press}, title = {{Lift-out cryo-FIBSEM and cryo-ET reveal the ultrastructural landscape of extracellular matrix}}, doi = {10.1083/jcb.202309125}, volume = {223}, year = {2024}, } @article{15018, abstract = {The epitaxial growth of a strained Ge layer, which is a promising candidate for the channel material of a hole spin qubit, has been demonstrated on 300 mm Si wafers using commercially available Si0.3Ge0.7 strain relaxed buffer (SRB) layers. The assessment of the layer and the interface qualities for a buried strained Ge layer embedded in Si0.3Ge0.7 layers is reported. The XRD reciprocal space mapping confirmed that the reduction of the growth temperature enables the 2-dimensional growth of the Ge layer fully strained with respect to the Si0.3Ge0.7. Nevertheless, dislocations at the top and/or bottom interface of the Ge layer were observed by means of electron channeling contrast imaging, suggesting the importance of the careful dislocation assessment. The interface abruptness does not depend on the selection of the precursor gases, but it is strongly influenced by the growth temperature which affects the coverage of the surface H-passivation. The mobility of 2.7 × 105 cm2/Vs is promising, while the low percolation density of 3 × 1010 /cm2 measured with a Hall-bar device at 7 K illustrates the high quality of the heterostructure thanks to the high Si0.3Ge0.7 SRB quality.}, author = {Shimura, Yosuke and Godfrin, Clement and Hikavyy, Andriy and Li, Roy and Aguilera Servin, Juan L and Katsaros, Georgios and Favia, Paola and Han, Han and Wan, Danny and de Greve, Kristiaan and Loo, Roger}, issn = {1369-8001}, journal = {Materials Science in Semiconductor Processing}, keywords = {Mechanical Engineering, Mechanics of Materials, Condensed Matter Physics, General Materials Science}, number = {5}, publisher = {Elsevier}, title = {{Compressively strained epitaxial Ge layers for quantum computing applications}}, doi = {10.1016/j.mssp.2024.108231}, volume = {174}, year = {2024}, } @article{14979, abstract = {Poxviruses are among the largest double-stranded DNA viruses, with members such as variola virus, monkeypox virus and the vaccination strain vaccinia virus (VACV). Knowledge about the structural proteins that form the viral core has remained sparse. While major core proteins have been annotated via indirect experimental evidence, their structures have remained elusive and they could not be assigned to individual core features. Hence, which proteins constitute which layers of the core, such as the palisade layer and the inner core wall, has remained enigmatic. Here we show, using a multi-modal cryo-electron microscopy (cryo-EM) approach in combination with AlphaFold molecular modeling, that trimers formed by the cleavage product of VACV protein A10 are the key component of the palisade layer. This allows us to place previously obtained descriptions of protein interactions within the core wall into perspective and to provide a detailed model of poxvirus core architecture. Importantly, we show that interactions within A10 trimers are likely generalizable over members of orthopox- and parapoxviruses.}, author = {Datler, Julia and Hansen, Jesse and Thader, Andreas and Schlögl, Alois and Bauer, Lukas W and Hodirnau, Victor-Valentin and Schur, Florian KM}, issn = {1545-9985}, journal = {Nature Structural & Molecular Biology}, keywords = {Molecular Biology, Structural Biology}, pages = {1114--1123}, publisher = {Springer Nature}, title = {{Multi-modal cryo-EM reveals trimers of protein A10 to form the palisade layer in poxvirus cores}}, doi = {10.1038/s41594-023-01201-6}, volume = {31}, year = {2024}, } @article{18581, abstract = {Background: Human induced pluripotent stem cells represent a scalable source of youthful tissue progenitors and secretomes for regenerative therapies. The aim of our study was to investigate the potential of conditioned medium (CM) from hiPSC-mesenchymal progenitors (hiPSC-MPs) to stimulate osteogenic differentiation of human bone marrow-derived mesenchymal stromal cells (MSCs). We also investigated whether prolonged cultivation or osteogenic pre-differentiation of hiPSC-MPs could enhance the stimulatory activity of CM. Methods: MSCs were isolated from 13 donors (age 20–90 years). CM derived from hiPSC-MPs was added to the MSC cultures and the effects on proliferation and osteogenic differentiation were examined after 14 days and 6 weeks. The stimulatory activity of hiPSC-MP-CM was compared with the activity of MSC-derived CM and with the activity of CM prepared from hiPSC-MPs pre-cultured in growth or osteogenic medium for 14 days. Comparative proteomic analysis of CM was performed to gain insight into the molecular components responsible for the stimulatory activity. Results: Primary bone marrow-derived MSC exhibited variability, with a tendency towards lower proliferation and tri-lineage differentiation in older donors. hiPSC-MP-CM increased the proliferation and alkaline phosphatase activity of MSC from several adult/aged donors after 14 days of continuous supplementation under osteogenic conditions. However, CM supplementation failed to improve the mineralization of MSC pellets after 6 weeks under osteogenic conditions. hiPSC-MP-CM showed greater enhancement of proliferation and ALP activity than CM derived from bone marrow-derived MSCs. Moreover, 14-day cultivation but not osteogenic pre-differentiation of hiPSC-MPs strongly enhanced CM stimulatory activity. Quantitative proteomic analysis of d14-CM revealed a distinct profile of components that formed a highly interconnected associations network with two clusters, one functionally associated with binding and organization of actin/cytoskeletal components and the other with structural constituents of the extracellular matrix, collagen, and growth factor binding. Several hub proteins were identified that were reported to have functions in cell-extracellular matrix interaction, osteogenic differentiation and development. Conclusions: Our data show that hiPSC-MP-CM enhances early osteogenic differentiation of human bone marrow-derived MSCs and that prolonged cultivation of hiPSC-MPs enhances CM-stimulatory activity. Proteomic analysis of the upregulated protein components provides the basis for further optimization of hiPSC-MP-CM for bone regenerative therapies.}, author = {Marolt Presen, Darja and Goeschl, Vanessa and Hanetseder, Dominik and Ogrin, Laura and Stetco, Alexandra Larissa and Tansek, Anja and Pozenel, Laura and Bruszel, Bella and Mitulovic, Goran and Oesterreicher, Johannes and Zipperle, Johannes and Schaedl, Barbara and Holnthoner, Wolfgang and Grillari, Johannes and Redl, Heinz}, issn = {1757-6512}, journal = {Stem Cell Research and Therapy}, publisher = {Springer Nature}, title = {{Prolonged cultivation enhances the stimulatory activity of hiPSC mesenchymal progenitor-derived conditioned medium}}, doi = {10.1186/s13287-024-03960-5}, volume = {15}, year = {2024}, } @article{15182, abstract = {Thermoelectric materials convert heat into electricity, with a broad range of applications near room temperature (RT). However, the library of RT high-performance materials is limited. Traditional high-temperature synthetic methods constrain the range of materials achievable, hindering the ability to surpass crystal structure limitations and engineer defects. Here, a solution-based synthetic approach is introduced, enabling RT synthesis of powders and exploration of densification at lower temperatures to influence the material's microstructure. The approach is exemplified by Ag2Se, an n-type alternative to bismuth telluride. It is demonstrated that the concentration of Ag interstitials, grain boundaries, and dislocations are directly correlated to the sintering temperature, and achieve a figure of merit of 1.1 from RT to 100 °C after optimization. Moreover, insights into and resolve Ag2Se's challenges are provided, including stoichiometry issues leading to irreproducible performances. This work highlights the potential of RT solution synthesis in expanding the repertoire of high-performance thermoelectric materials for practical applications.}, author = {Kleinhanns, Tobias and Milillo, Francesco and Calcabrini, Mariano and Fiedler, Christine and Horta, Sharona and Balazs, Daniel and Strumolo, Marissa J. and Hasler, Roger and Llorca, Jordi and Tkadletz, Michael and Brutchey, Richard L. and Ibáñez, Maria}, issn = {1614-6840}, journal = {Advanced Energy Materials}, number = {22}, publisher = {Wiley}, title = {{A route to high thermoelectric performance: Solution‐based control of microstructure and composition in Ag2Se}}, doi = {10.1002/aenm.202400408}, volume = {14}, year = {2024}, } @misc{22803, abstract = {In this study, we analyzed the efficiency of different adeno-associated viral (AAV) injections in transfecting neurons in the salamander Pleurodeles waltl. To query sources of variation in AAV injection outcomes, we analyzed metadata and outcomes for an additional 68 intraparenchymal injections performed 39 in post-metamorphic Pleurodeles salamanders. This dataset included both quantitative variables (age, weight, viral genomes (v.g.) injected, and a cell transduction score ranging from 0 to 4, see STAR Methods) and categorical variables (here referred to as qualitative variables: serotype, promoter, reporter, single vs. dual injection, manufacturer, and injection site). To assess the associations between these variables, we performed a Factor Analysis for Mixed Data (FAMD), a principal component method that is designed to determine significant sources of variability within datasets that contain both quantitative and qualitative data types. This dataset contains the injection outcomes and metadata for AAV injections administered in the salamander Pleurodeles waltl. The RactoMineR package (https://CRAN.R-project.org/package=FactoMineR) was used to determine significant contributions of a number of variables contributing to injection outcomes. Analysis of these data revealed that, among other factors, age co-varies with injection score. Therefore, we conclude that increased animal age decreases the efficacy of this tool.}, author = {Jaeger, Eliza}, publisher = {Repository}, title = {{Multivariate analysis of Pleurodeles waltl injection outcomes using FAMD FactoMineR (RStudio 4.3.2) used to probe sources of variability during an Adeno-associated viral (AAV) screen}}, doi = {10.5061/dryad.mpg4f4r89}, year = {2024}, } @article{17479, abstract = {Phonon polaritons (PhPs), light coupled to lattice vibrations, in the highly anisotropic polar layered material molybdenum trioxide (α-MoO3) are currently the focus of intense research efforts due to their extreme subwavelength field confinement, directional propagation, and unprecedented low losses. Nevertheless, prior research has primarily concentrated on exploiting the squeezing and steering capabilities of α-MoO3 PhPs, without inquiring much into the dominant microscopic mechanism that determines their long lifetimes, which is key for their implementation in nanophotonic applications. This study delves into the fundamental processes that govern PhP damping in α-MoO3 by combining ab initio calculations with scattering-type scanning near-field optical microscopy (s-SNOM) and Fourier transform infrared (FTIR) spectroscopy measurements across a broad temperature range (8–300 K). The remarkable agreement between our theoretical predictions and experimental observations allows us to identify third-order anharmonic phonon–phonon scattering as the main damping mechanism of α-MoO3 PhPs. These findings shed light on the fundamental limits of low-loss PhPs, which is a crucial factor for assessing their implementation into nanophotonic devices.}, author = {Taboada-Gutiérrez, Javier and Zhou, Yixi and Tresguerres-Mata, Ana I.F. and Lanza, Christian and Martínez-Suárez, Abel and Álvarez-Pérez, Gonzalo and Duan, Jiahua and Martín, José Ignacio and Vélez, María and Prieto Gonzalez, Ivan and Bercher, Adrien and Teyssier, Jérémie and Errea, Ion and Nikitin, Alexey Y. and Martín-Sánchez, Javier and Kuzmenko, Alexey B. and Alonso-González, Pablo}, issn = {2330-4022}, journal = {ACS Photonics}, number = {9}, pages = {3570--3577}, publisher = {American Chemical Society}, title = {{Unveiling the mechanism of phonon-polariton damping in α‑MoO3}}, doi = {10.1021/acsphotonics.4c00485}, volume = {11}, year = {2024}, } @article{18168, abstract = {Despite the considerable interest in the recombinant production of synthetic spider silk fibers that possess mechanical properties similar to those of native spider silks, such as the cost-effectiveness, tunability, and scalability realization, is still lacking. To address this long-standing challenge, we have constructed an artificial spider silk gene using Golden Gate assembly for the recombinant bacterial production of dragline-mimicking silk, incorporating all the essential components: the N-terminal domain, a 33-residue-long major-ampullate-spidroin-inspired segment repeated 16 times, and the C-terminal domain (N16C). This designed silk-like protein was successfully expressed in Escherichia coli, purified, and cast into films from formic acid. We produced uniformly 13C–15N-labeled N16C films and employed solid-state magic-angle spinning nuclear magnetic resonance (NMR) for characterization. Thus, we could demonstrate that our bioengineered silk-like protein self-assembles into a film where, when hydrated, the solvent-exposed layer of the rigid, β-nanocrystalline polyalanine core undergoes a transition to an α-helical structure, gaining mobility to the extent that it fully dissolves in water and transforms into a highly dynamic random coil. This hydration-induced behavior induces chain dynamics in the glycine-rich amorphous soft segments on the microsecond time scale, contributing to the elasticity of the solid material. Our findings not only reveal the presence of structurally and dynamically distinct segments within the film’s superstructure but also highlight the complexity of the self-organization responsible for the exceptional mechanical properties observed in proteins that mimic dragline silk.}, author = {Wu, Dongqing and Koscic, Anamaria and Schneider, Sonja and Dubini, Romeo C. A. and Rodriguez Camargo, Diana C. and Schneider, Sabine and Rovo, Petra}, issn = {1526-4602}, journal = {Biomacromolecules}, number = {3}, pages = {1759--1774}, publisher = {American Chemical Society}, title = {{Unveiling the dynamic self-assembly of a recombinant dragline-silk-mimicking protein}}, doi = {10.1021/acs.biomac.3c01239}, volume = {25}, year = {2024}, } @article{15164, abstract = {Primary implant stability, which refers to the stability of the implant during the initial healing period is a crucial factor in determining the long-term success of the implant and lays the foundation for secondary implant stability achieved through osseointegration. Factors affecting primary stability include implant design, surgical technique, and patient-specific factors like bone quality and morphology. In vivo, the cyclic nature of anatomical loading puts osteosynthesis locking screws under dynamic loads, which can lead to the formation of micro cracks and defects that slowly degrade the mechanical connection between the bone and screw, thus compromising the initial stability and secondary stability of the implant. Monotonic quasi-static loading used for testing the holding capacity of implanted screws is not well suited to capture this behavior since it cannot capture the progressive deterioration of peri‑implant bone at small displacements. In order to address this issue, this study aims to determine a critical point of loss of primary implant stability in osteosynthesis locking screws under cyclic overloading by investigating the evolution of damage, dissipated energy, and permanent deformation. A custom-made test setup was used to test implanted 2.5 mm locking screws under cyclic overloading test. For each loading cycle, maximum forces and displacement were recorded as well as initial and final cycle displacements and used to calculate damage and energy dissipation evolution. The results of this study demonstrate that for axial, shear, and mixed loading significant damage and energy dissipation can be observed at approximately 20 % of the failure force. Additionally, at this load level, permanent deformations on the screw-bone interface were found to be in the range of 50 to 150 mm which promotes osseointegration and secondary implant stability. This research can assist surgeons in making informed preoperative decisions by providing a better understanding of the critical point of loss of primary implant stability, thus improving the long-term success of the implant and overall patient satisfaction.}, author = {Silva-Henao, Juan D. and Schober, Sophie and Pahr, Dieter H. and Reisinger, Andreas G.}, issn = {1873-4030}, journal = {Medical Engineering and Physics}, publisher = {Elsevier}, title = {{Critical loss of primary implant stability in osteosynthesis locking screws under cyclic overloading}}, doi = {10.1016/j.medengphy.2024.104143}, volume = {126}, year = {2024}, }