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- ItemDeformation characteristics of solid-state benzene as a step towards understanding planetary geology([London] : Nature Publishing Group UK, 2022) Zhang, Wenxin; Zhang, Xuan; Edwards, Bryce W.; Zhong, Lei; Gao, Huajian; Malaska, Michael J.; Hodyss, Robert; Greer, Julia R.Small organic molecules, like ethane and benzene, are ubiquitous in the atmosphere and surface of Saturn’s largest moon Titan, forming plains, dunes, canyons, and other surface features. Understanding Titan’s dynamic geology and designing future landing missions requires sufficient knowledge of the mechanical characteristics of these solid-state organic minerals, which is currently lacking. To understand the deformation and mechanical properties of a representative solid organic material at space-relevant temperatures, we freeze liquid micro-droplets of benzene to form ~10 μm-tall single-crystalline pyramids and uniaxially compress them in situ. These micromechanical experiments reveal contact pressures decaying from ~2 to ~0.5 GPa after ~1 μm-reduction in pyramid height. The deformation occurs via a series of stochastic (~5-30 nm) displacement bursts, corresponding to densification and stiffening of the compressed material during cyclic loading to progressively higher loads. Molecular dynamics simulations reveal predominantly plastic deformation and densified region formation by the re-orientation and interplanar shear of benzene rings, providing a two-step stiffening mechanism. This work demonstrates the feasibility of in-situ cryogenic nanomechanical characterization of solid organics as a pathway to gain insights into the geophysics of planetary bodies.
- ItemThe human TRPA1 intrinsic cold and heat sensitivity involves separate channel structures beyond the N-ARD domain([London] : Nature Publishing Group UK, 2022) Moparthi, Lavanya; Sinica, Viktor; Moparthi, Vamsi K.; Kreir, Mohamed; Vignane, Thibaut; Filipovic, Milos R.; Vlachova, Viktorie; Zygmunt, Peter M.TRP channels sense temperatures ranging from noxious cold to noxious heat. Whether specialized TRP thermosensor modules exist and how they control channel pore gating is unknown. We studied purified human TRPA1 (hTRPA1) truncated proteins to gain insight into the temperature gating of hTRPA1. In patch-clamp bilayer recordings, ∆1–688 hTRPA1, without the N-terminal ankyrin repeat domain (N-ARD), was more sensitive to cold and heat, whereas ∆1–854 hTRPA1, also lacking the S1–S4 voltage sensing-like domain (VSLD), gained sensitivity to cold but lost its heat sensitivity. In hTRPA1 intrinsic tryptophan fluorescence studies, cold and heat evoked rearrangement of VSLD and the C-terminus domain distal to the transmembrane pore domain S5–S6 (CTD). In whole-cell electrophysiology experiments, replacement of the CTD located cysteines 1021 and 1025 with alanine modulated hTRPA1 cold responses. It is proposed that hTRPA1 CTD harbors cold and heat sensitive domains allosterically coupled to the S5–S6 pore region and the VSLD, respectively.
- ItemTailoring electron beams with high-frequency self-assembled magnetic charged particle micro optics([London] : Nature Publishing Group UK, 2022) Huber, R.; Kern, F.; Karnaushenko, D.D.; Eisner, E.; Lepucki, P.; Thampi, A.; Mirhajivarzaneh, A.; Becker, C.; Kang, T.; Baunack, S.; Büchner, B.; Karnaushenko, D.; Schmidt, O.G.; Lubk, A.Tunable electromagnets and corresponding devices, such as magnetic lenses or stigmators, are the backbone of high-energy charged particle optical instruments, such as electron microscopes, because they provide higher optical power, stability, and lower aberrations compared to their electric counterparts. However, electromagnets are typically macroscopic (super-)conducting coils, which cannot generate swiftly changing magnetic fields, require active cooling, and are structurally bulky, making them unsuitable for fast beam manipulation, multibeam instruments, and miniaturized applications. Here, we present an on-chip microsized magnetic charged particle optics realized via a self-assembling micro-origami process. These micro-electromagnets can generate alternating magnetic fields of about ±100 mT up to a hundred MHz, supplying sufficiently large optical power for a large number of charged particle optics applications. That particular includes fast spatiotemporal electron beam modulation such as electron beam deflection, focusing, and wave front shaping as required for stroboscopic imaging.
- ItemGlobal crop yields can be lifted by timely adaptation of growing periods to climate change([London] : Nature Publishing Group UK, 2022) Minoli, Sara; Jägermeyr, Jonas; Asseng, Senthold; Urfels, Anton; Müller, ChristophAdaptive management of crop growing periods by adjusting sowing dates and cultivars is one of the central aspects of crop production systems, tightly connected to local climate. However, it is so far underrepresented in crop-model based assessments of yields under climate change. In this study, we integrate models of farmers’ decision making with biophysical crop modeling at the global scale to simulate crop calendars adaptation and its effect on crop yields of maize, rice, sorghum, soybean and wheat. We simulate crop growing periods and yields (1986-2099) under counterfactual management scenarios assuming no adaptation, timely adaptation or delayed adaptation of sowing dates and cultivars. We then compare the counterfactual growing periods and corresponding yields at the end of the century (2080-2099). We find that (i) with adaptation, temperature-driven sowing dates (typical at latitudes >30°N-S) will have larger shifts than precipitation-driven sowing dates (at latitudes <30°N-S); (ii) later-maturing cultivars will be needed, particularly at higher latitudes; (iii) timely adaptation of growing periods would increase actual crop yields by ~12%, reducing climate change negative impacts and enhancing the positive CO2 fertilization effect. Despite remaining uncertainties, crop growing periods adaptation require consideration in climate change impact assessments.
- ItemPotential impacts of climate change on agriculture and fisheries production in 72 tropical coastal communities(London : Nature Publishing Group, 2022) Cinner, Joshua E; Caldwell, Iain R; Thiault, Lauric; Ben, John; Blanchard, Julia L; Coll, Marta; Diedrich, Amy; Eddy, Tyler D; Everett, Jason D; Folberth, Christian; Gascuel, Didier; Guiet, Jerome; Gurney, Georgina G; Heneghan, Ryan F; Jägermeyr, Jonas; Jiddawi, Narriman; Lahari, Rachael; Kuange, John; Liu, Wenfeng; Maury, Olivier; Müller, Christoph; Novaglio, Camilla; Palacios-Abrantes, Juliano; Petrik, Colleen M; Rabearisoa, Ando; Tittensor, Derek P; Wamukota, Andrew; Pollnac, RichardClimate change is expected to profoundly affect key food production sectors, including fisheries and agriculture. However, the potential impacts of climate change on these sectors are rarely considered jointly, especially below national scales, which can mask substantial variability in how communities will be affected. Here, we combine socioeconomic surveys of 3,008 households and intersectoral multi-model simulation outputs to conduct a sub-national analysis of the potential impacts of climate change on fisheries and agriculture in 72 coastal communities across five Indo-Pacific countries (Indonesia, Madagascar, Papua New Guinea, Philippines, and Tanzania). Our study reveals three key findings: First, overall potential losses to fisheries are higher than potential losses to agriculture. Second, while most locations (> 2/3) will experience potential losses to both fisheries and agriculture simultaneously, climate change mitigation could reduce the proportion of places facing that double burden. Third, potential impacts are more likely in communities with lower socioeconomic status.
- ItemOn-chip integrated process-programmable sub-10 nm thick molecular devices switching between photomultiplication and memristive behaviour([London] : Nature Publishing Group UK, 2022) Li, Tianming; Hantusch, Martin; Qu, Jiang; Bandari, Vineeth Kumar; Knupfer, Martin; Zhu, Feng; Schmidt, Oliver G.Molecular devices constructed by sub-10 nm thick molecular layers are promising candidates for a new generation of integratable nanoelectronic applications. Here, we report integrated molecular devices based on ultrathin copper phthalocyanine/fullerene hybrid layers with microtubular soft-contacts, which exhibit process-programmable functionality switching between photomultiplication and memristive behaviour. The local electric field at the interface between the polymer bottom electrode and the enclosed molecular channels modulates the ionic-electronic charge interaction and hence determines the transition of the device function. When ions are not driven into the molecular channels at a low interface electric field, photogenerated holes are trapped as electronic space charges, resulting in photomultiplication with a high external quantum efficiency. Once mobile ions are polarized and accumulated as ionic space charges in the molecular channels at a high interface electric field, the molecular devices show ferroelectric-like memristive switching with remarkable resistive ON/OFF and rectification ratios.
- ItemGlycolytic flux control by drugging phosphoglycolate phosphatase([London] : Nature Publishing Group UK, 2022) Jeanclos, Elisabeth; Schlötzer, Jan; Hadamek, Kerstin; Yuan-Chen, Natalia; Alwahsh, Mohammad; Hollmann, Robert; Fratz, Stefanie; Yesilyurt-Gerhards, Dilan; Frankenbach, Tina; Engelmann, Daria; Keller, Angelika; Kaestner, Alexandra; Schmitz, Werner; Neuenschwander, Martin; Hergenröder, Roland; Sotriffer, Christoph; von Kries, Jens Peter; Schindelin, Hermann; Gohla, AntjeTargeting the intrinsic metabolism of immune or tumor cells is a therapeutic strategy in autoimmunity, chronic inflammation or cancer. Metabolite repair enzymes may represent an alternative target class for selective metabolic inhibition, but pharmacological tools to test this concept are needed. Here, we demonstrate that phosphoglycolate phosphatase (PGP), a prototypical metabolite repair enzyme in glycolysis, is a pharmacologically actionable target. Using a combination of small molecule screening, protein crystallography, molecular dynamics simulations and NMR metabolomics, we discover and analyze a compound (CP1) that inhibits PGP with high selectivity and submicromolar potency. CP1 locks the phosphatase in a catalytically inactive conformation, dampens glycolytic flux, and phenocopies effects of cellular PGP-deficiency. This study provides key insights into effective and precise PGP targeting, at the same time validating an allosteric approach to control glycolysis that could advance discoveries of innovative therapeutic candidates.
- ItemDimensional reduction and incommensurate dynamic correlations in the S=1/2 triangular-lattice antiferromagnet Ca3ReO5Cl2([London] : Nature Publishing Group UK, 2022) Zvyagin, S.A.; Ponomaryov, A.N.; Wosnitza, J.; Hirai, D.; Hiroi, Z.; Gen, M.; Kohama, Y.; Matsuo, A.; Matsuda, Y.H.; Kindo, K.The observation of spinon excitations in the S=1/2 triangular antiferromagnet Ca3ReO5Cl2 reveals a quasi-one-dimensional (1D) nature of magnetic correlations, in spite of the nominally 2D magnetic structure. This phenomenon is known as frustration-induced dimensional reduction. Here, we present high-field electron spin resonance spectroscopy and magnetization studies of Ca3ReO5Cl2, allowing us not only to refine spin-Hamiltonian parameters, but also to investigate peculiarities of its low-energy spin dynamics. We argue that the presence of the uniform Dzyaloshinskii-Moriya interaction (DMI) shifts the spinon continuum in momentum space and, as a result, opens a zero-field gap at the Γ point. We observed this gap directly. The shift is found to be consistent with the structural modulation in the ordered state, suggesting this material as a perfect model triangular-lattice system, where a pure DMI-spiral ground state can be realized.
- ItemA new dimension for magnetosensitive e-skins: active matrix integrated micro-origami sensor arrays([London] : Nature Publishing Group UK, 2022) Becker, Christian; Bao, Bin; Karnaushenko, Dmitriy D.; Bandari, Vineeth Kumar; Rivkin, Boris; Li, Zhe; Faghih, Maryam; Karnaushenko, Daniil; Schmidt, Oliver G.Magnetic sensors are widely used in our daily life for assessing the position and orientation of objects. Recently, the magnetic sensing modality has been introduced to electronic skins (e-skins), enabling remote perception of moving objects. However, the integration density of magnetic sensors is limited and the vector properties of the magnetic field cannot be fully explored since the sensors can only perceive field components in one or two dimensions. Here, we report an approach to fabricate high-density integrated active matrix magnetic sensor with three-dimensional (3D) magnetic vector field sensing capability. The 3D magnetic sensor is composed of an array of self-assembled micro-origami cubic architectures with biased anisotropic magnetoresistance (AMR) sensors manufactured in a wafer-scale process. Integrating the 3D magnetic sensors into an e-skin with embedded magnetic hairs enables real-time multidirectional tactile perception. We demonstrate a versatile approach for the fabrication of active matrix integrated 3D sensor arrays using micro-origami and pave the way for new electronic devices relying on the autonomous rearrangement of functional elements in space.
- ItemTargeting cardiomyocyte ADAM10 ectodomain shedding promotes survival early after myocardial infarction([London] : Nature Publishing Group UK, 2022) Klapproth, Erik; Witt, Anke; Klose, Pauline; Wiedemann, Johanna; Vavilthota, Nikitha; Künzel, Stephan R.; Kämmerer, Susanne; Günscht, Mario; Sprott, David; Lesche, Mathias; Rost, Fabian; Dahl, Andreas; Rauch, Erik; Kattner, Lars; Weber, Silvio; Mirtschink, Peter; Kopaliani, Irakli; Guan, Kaomei; Lorenz, Kristina; Saftig, Paul; Wagner, Michael; El-Armouche, AliAfter myocardial infarction the innate immune response is pivotal in clearing of tissue debris as well as scar formation, but exaggerated cytokine and chemokine secretion with subsequent leukocyte infiltration also leads to further tissue damage. Here, we address the value of targeting a previously unknown a disintegrin and metalloprotease 10 (ADAM10)/CX3CL1 axis in the regulation of neutrophil recruitment early after MI. We show that myocardial ADAM10 is distinctly upregulated in myocardial biopsies from patients with ischemia-driven cardiomyopathy. Intriguingly, upon MI in mice, pharmacological ADAM10 inhibition as well as genetic cardiomycyte-specific ADAM10 deletion improves survival with markedly enhanced heart function and reduced scar size. Mechanistically, abolished ADAM10-mediated CX3CL1 ectodomain shedding leads to diminished IL-1β-dependent inflammation, reduced neutrophil bone marrow egress as well as myocardial tissue infiltration. Thus, our data shows a conceptual insight into how acute MI induces chemotactic signaling via ectodomain shedding in cardiomyocytes.