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A key characteristic of subduction zones is that lithologies in slabs undergo prograde devolatilization while simultaneously being subject to deformation. A growing number of studies suggest that dissolution-precipitation creep may be the dominant deformation mechanism when fluid is present [1] and that the related fabric development and weakening are most pronounced during metamorphic reaction [2]. Here we investigate the microstructural and textural evolution of meta-ophicarbonate lenses hosted in Atg-serpentinite and Chl-harzburgite of the Milagrosa and Almirez ultramafic massifs in the Nevado-Filábride Complex (Betic Cordillera, S. Spain), which record high-pressure alpine subduction metamorphism. Similar rocks typically occur along tectonized lithological contacts between peridotite and mafic or sedimentary units, thus they can be ideal archives of focused deformation, prograde devolatilization and large scale fluxing by fluid from high-P serpentinite dehydration in subduction zones. In Milagrosa, serpentinite-hosted ophicarbonates —formed after variable mixtures of Ca-carbonate and serpentine— underwent prograde metamorphism to foliated antigorite-diopside-dolomite rocks and Ti-clinohumite-bearing diopside marbles (550 – 600 °C, 1.0 – 1.4 GPa). In Almirez, ophicarbonates were transformed to high-grade assemblages of Ti-clinohumite, olivine, diopside, chlorite, aragonite and dolomite (650 – 680 °C, 1.7 – 1.9 GPa) [3]. We combine microstructural and textural data obtained from electron backscatter diffraction (EBSD) and optical cathodoluminescence (CL) imaging to investigate the relationship between deformation and metamorphic devolatilization during prograde metamorphism. In Milagrosa, Atg-serpentinites show a fabric with a crystallographic preferred orientation (CPO) of antigorite typical of high-P Atg-serpentinites in subduction zones. Antigorite in antigorite-diopside-dolomite rocks displays the same fabric, with a c-axes maximum coinciding with the pole to the foliation, and diopside c-axes parallel to lineation. Dolomite and calcite in the Milagrosa meta-ophicarbonate lenses have a consistent CPO with their c-axes orientated subparallel to that of antigorite, which correlates with the poles to (100) of diopside. In foliated meta-ophicarbonates at Almirez, diopside, dolomite and calcite show a very similar distribution of their crystallographic axes with respect to foliation. CL imaging reveals concentric core-rim zoning of diopside and dolomite in both localities. Clusters of aragonite inclusions indicate that all zoning generations in diopside formed at high-P by growth and/or dissolution-reprecipitation.These zoning patterns and low intra-grain misorientations point to diffusion creep by dissolution-precipitation as the dominant deformation mechanism. The strong correlation of diopside, carbonate and antigorite CPOs may have been caused by oriented crystal growth under differential stress and anisotropic fluid flow in the reacting ophicarbonate. We infer that antigorite dehydration in meta-ophicarbonate at 580 – 600 °C is related to transient ductile deformation enhancing fluid drainage, followed by compaction and an increased bulk rock strength once all antigorite devolatilizes. This causes deformation and fluid flow during dehydration of the host serpentinite at 650 °C to focus around the meta-ophicarbonate lenses, shielding carbonate from dissolution at subarc conditions. [1] Malvoisin & Baumgartner (2021) G³; https://doi.org/10.1029/2021GC009633[2] Stünitz et al. (2020) JSG; https://doi.org/10.1016/j.jsg.2020.104129[3] Menzel et al. (2019) JMG; https://doi.org/10.1111/jmg.12481M.D.M acknowledges funding of Junta de Andalucía (Postdoc_21_00791)

Pervasive carbonation of serpentinized peridotite to carbonate-quartz rock (listvenite) due to infiltration of CO2-bearing fluid is a remarkable process because it can be geologically fast and it increases the rock’s carbon content from initially zero to > 30 wt% CO2. This pervasive conversion is related to an overall solid volume increase while at the same time requiring high time-integrated fluid rock ratios with permeability and diffusivity on all scales. Thus, porosity has to be created dynamically during reaction progress as otherwise fluid pathways become clogged by the reaction products carbonate and quartz, which is one of the major obstacles for artificial carbon storage by peridotite carbonation. Processes that can renew porosity and permeability during carbonation are fracturing and veining – in response to tectonic stress [1] or induced by reaction and crystal growth [2], or a combination of both –, reaction-enhanced ductile deformation [3,4], and spatial decoupling of dissolution and precipitation with solute transfer at different length scales.Using SEM, EBSD, TEM and FIB nano-tomography, we investigated the microstructural record of local solute transfer and its role for porosity renewal in natural carbonate-bearing serpentinites, transitional serpentine-carbonate-quartz assemblages and listvenites from the Samail Ophiolite, Oman. The clearest indicators of pervasive replacement accommodated by local solute transfer are pseudomorphic replacement structures where carbonate and quartz occur in distinct microstructures corresponding to different inherited peridotite and serpentinite textures. A common pseudomorphic replacement structure in the Samail carbonated peridotite are quartz-fuchsite intergrowths replacing bastite (pseudomorphs after orthopyroxene) in listvenite with harzburgite protoliths. A local strong crystallographic alignment of quartz in each of the bastite/pyroxene pseudomorphs suggests that the anisotropic porosity structure of bastite serpentine favored oriented, epitaxial growth of quartz. Transitional serpentine-carbonate-quartz assemblages show that the first quartz and carbonate generations precipitate coeval but spatially separated, with distinct crystal habits. FIB nano-tomography, STEM analysis and high resolution SEM on ion-polished samples of a transitional serpentine-dolomite-quartz rock from the carbonation reaction front show nano-porous fluid channels in fibrous serpentine at high angle to a highly serrated carbonate-serpentine replacement contact. These nano-scale fluid channels facilitated bidirectional mass exchange of Ca, C, Mg and Si bearing solutes between sites of preferential replacement, such as the cores of serpentine mesh textures, and larger-scale permeability networks along veins and fractures. These observations imply that massive and pervasive solute transfer through the reacting serpentine matrix is possible on a small scale, without clogging of porosity by immediate co-precipitation of quartz or Mg-silicates. Spatial decoupling of dissolution and precipitation was likely caused by the dynamically evolving composition of the reacting fluid and/or due to the influence of differential stress and volumetric strain – a mechanism that can compensate on a local scale for the volume expansion expected of isochemical carbonation reactions. [1] Menzel et al., Solid Earth, 2022; https://doi.org/10.5194/se-2021-152[2] Kelemen & Hirth, EPSL, 2012; https://doi.org/10.1016/j.epsl.2012.06.018[3] Menzel et al., Nature Communications, 2022; https://doi.org/10.1038/s41467-022-31049-1[4] Kelemen et al., JGR, 2022; https://doi.org/10.1029/2021JB022352 Funding: Junta de Andalucía (Postdoc_21_00791); DFG grants UR 64/20-1, UR 64/17-1; and EU Horizon 2020 Transnational Access EXCITE _C1_2022_34.

European journal of mineralogy : EJM 35(2), 171-187 (2023). doi:10.5194/ejm-35-171-2023, Published by Copernicus Publications, Göttingen

Solid earth : SE 13(8), 1191-1218 (2022). doi:10.5194/se-13-1191-2022, Published by Copernicus Publ., Göttingen

Pain is the main complication of sickle cell disease (SCD). Individuals with SCD experience acute pain episodes and chronic daily pain, both of which are managed with opioids. Opioids have deleterious side effects and use-associated stigma that make them less than ideal for SCD pain management. After recognizing the neuropathic qualities of SCD pain, clinically-approved therapies for neuropathic pain, including gabapentin, now present unique non-opioid based therapies for SCD pain management. These experiments explored the efficacy of gabapentin in relieving evoked and spontaneous chronic pain, and hypoxia/reoxygenation (H/R)-induced acute pain in mouse models of SCD. When administered following H/R, a single dose of gabapentin alleviated mechanical hypersensitivity in SCD mice by decreasing peripheral fibre activity. Gabapentin treatment also alleviated spontaneous ongoing pain in SCD mice. Longitudinal daily administration of gabapentin failed to alleviate H/R-induced pain or chronic evoked mechanical, cold or deep tissue hypersensitivity in SCD mice. Consistent with this observation, voltage-gated calcium channel (VGCC) α(2)δ(1) subunit expression was similar in sciatic nerve, dorsal root ganglia and lumbar spinal cord tissue from SCD and control mice. Based on these data, gabapentin may be an effective opioid alternative for the treatment of chronic spontaneous and acute H/R pain in SCD.

Postoperative pain management continues to be suboptimal because of the lack of effective nonopioid therapies and absence of understanding of sex-driven differences. Here, we asked how the NLRP3 inflammasome contributes to postoperative pain. Inflammasomes are mediators of the innate immune system that are responsible for activation and secretion of IL-1β upon stimulation by specific molecular signals. Peripheral IL-1β is known to contribute to the mechanical sensitization induced by surgical incision. However, it is not known which inflammasome mediates the IL-1β release after surgical incision. Among the 9 known inflammasomes, the NLRP3 inflammasome is ideally positioned to drive postoperative pain through IL-1β production because NLRP3 can be activated by factors that are released by incision. Here, we show that male mice that lack NLRP3 (NLRP3) recover from surgery-induced behavioral and neuronal mechanical sensitization faster and display less surgical site inflammation than mice expressing NLRP3 (wild-type). By contrast, female NLRP3 mice exhibit minimal attenuation of the postoperative mechanical hypersensitivity and no change in postoperative inflammation compared with wild-type controls. Sensory neuron-specific deletion of NLRP3 revealed that in males, NLRP3 expressed in non-neuronal cells and potentially sensory neurons drives postoperative pain. However, in females, only the NLRP3 that may be expressed in sensory neurons contributes to postoperative pain where the non-neuronal cell contribution is NLRP3 independent. This is the first evidence of a key role for NLRP3 in postoperative pain and reveals immune-mediated sex differences in postoperative pain.

s & presentations : EGU General Assembly 2021 / European Geosciences Union. General Assembly EGU General Assembly 2021, vEGU21, online, 19 Apr 2021 - 30 Apr 2021; Göttingen : Copernicus Gesellschaft mbH EGU21-10718 (2021). doi:10.5194/egusphere-egu21-10718, Published by Copernicus Gesellschaft mbH, Göttingen

Epidermal keratinocytes mediate touch sensation by detecting and encoding tactile information to sensory neurons. However, the specific mechanotransducers that enable keratinocytes to respond to mechanical stimulation are unknown. Here, we found that the mechanically-gated ion channel PIEZO1 is a key keratinocyte mechanotransducer. Keratinocyte expression of PIEZO1 is critical for normal sensory afferent firing and behavioral responses to mechanical stimuli in mice.

Hole BT1B of the Oman Drilling Project provides a continuous sampling from listvenite into the metamorphic sole that preserves the deformation, hydration and carbonation processes of oceanic mantle peridotite at the base of the Samail ophiolite, Oman. We present evidence of multistage brittle deformation in listvenites and serpentinites based on field observations, visual core logging and petrography. About 10 vol% of listvenite and serpentinite in Hole BT1B is composed of cataclasite bands. Cataclasites contain lithic clasts of listvenite with spheroidal, zoned magnesite and quartz, and fragments of chalcedony-carbonate veins ¬¬that elsewhere crosscut listvenite — showing that cataclasis post-dates listvenite formation. Locally the cataclasites are reworked and cut by thin, sharp faults, pointing to repeated reactivation of brittle structures. SEM-EDS mapping shows that cataclasis was related to silica cementation and/or dissolution of carbonate. Dolomite veins crosscut cataclasites and breccias, suggesting that part of the Ca gain in BT1B is related to late fluids after listvenite formation. These results indicate a multistage tectonic overprint after peridotite carbonation and listvenite formation, which may be related to the tectonic history of the deformed continental margin under the ophiolite. These relatively late brittle structures should be excluded when trying to understand the carbonation of peridotite to listvenite.

Epidermal keratinocytes mediate touch sensation by detecting and encoding tactile information to sensory neurons. However, the specific mechanotransducers that enable keratinocytes to respond to mechanical stimulation are unknown. Here, we found that the mechanically-gated ion channel Piezo1 is the major keratinocyte mechanotransducer. Keratinocyte expression of Piezo1 is critical for normal sensory afferent firing and behavioral responses to mechanical stimuli.

Climate is regulated by the carbonate–silicate cycle in which slab outgassing of C into deep fluids and volcanic degassing of CO into the atmosphere are an important part. However, the mechanisms of C mobility in subduction zones remain largely unresolved. Previous research has focused mainly on investigating the upward transfer of slab-derived carbonic fluids for the forearc mantle metasomatism and partial melting. Furthermore, percolation of CO-bearing fluids parallel to the downgoing plates can potentially drive carbonation of subducted rocks, which influences the global estimates of C fluxes at convergent margins. Nevertheless, the geological conditions and processes leading to the carbonation of subduction-zone lithologies by fluid–rock interactions are still poorly understood. Here, we present new field, petrological, and isotopic results of carbonated serpentinites—high-pressure (HP) ophidolomites and low-pressure (LP) ophimagnesites and listvenites—from the Chinese southwestern Tianshan HP–UHP metamorphic belt. These rocks recorded the carbonation of subduction-zone serpentinites at HP and LP conditions during exhumation, reflecting the multistage transfer and infiltration of carbonic fluids along the plate boundary. The HP ophidolomites are characterized by the growth of carbonates (dolomite, aragonite, and Mg-calcite) at the expense of silicates in the host serpentinites. Integrated Sr–C–O isotopic data and thermodynamic modelling suggest that carbonic fluids (containing a CO concentration of up to 1.9 molal) emanating from carbonate-bearing metamafic rocks (e.g., eclogites) likely contributed to HP carbonation of serpentinites at about 15–25 kbar and 550–600 °C. The close contact of ophidolomites and carbonated metasedimentary rocks in the field as well as their similarities in Sr isotope compositions suggests that the latter could also have acted as the possible C source. Alternatively, both lithologies may have formed by coupled HP carbonation along the lithological interface between serpentinites and metasedimentary rocks. Subsequent fluid–rock interactions at relatively shallow crustal levels resulted in a second stage of serpentinite carbonation to form LP ophimagnesites and listvenites, during which the metasomatic CO-bearing fluids may have originated from metasedimentary rocks. The multistage CO sequestration in subduction-zone serpentinites implies that hydrated ultramafic rocks in subducted slabs are highly effective reactants to capture and store slab-released C over a wide range of P–T conditions, with the potential to substantially control the C distribution between shallow and deep reservoirs and thus modulate C fluxes in subduction zones., This work was financially supported by The National Natural Science Foundation of China (41520104004, 41330210, and 41872067) and The National Basic Research Program of China (2015CB856105). The first author is deeply indebted to an invitation from Stefano Poli and a scholarship from Graduate School of Peking University (2018-02-005) for supporting his PhD study in Italy. We are grateful to Thomas Bader, Ryosuke Oyanagi, José Alberto Padrón-Navarta, and Zhou Tan for helpful discussions. We thank Zhicheng Liu and Yang Wang for their help during fieldwork. We also thank Hongrui Ding, Wennian Han, Xiangtian Jin, Xiaoli Li, Dongdong Ma, Fang Ma, Hong Qin, Zhaofeng Zhang, Hongli Zhu, and Wenping Zhu for their patient assistance during sample analyses. Alberto Vitale Brovarone participation in this research was supported by the French ANR T-ERC grant, and by the Italian Levi Montalcini program by MIUR. The authors wish to acknowledge Esther Schwarzenbach, Melanie Sieber, and an anonymous reviewer for their detailed and constructive comments that substantially helped to improve the manuscript. Wolfgang Bach is greatly appreciated for his editorial handling and helpful suggestions.

s & presentations : EGU General Assembly 2020 EGU General Assembly 2020, EGU2020, online, 4 May 2020 - 8 May 2020; G��ttingen : Copernicus Gesellschaft mbH EGU2020-11027 (2020). doi:10.5194/egusphere-egu2020-11027, Published by Copernicus Gesellschaft mbH, G��ttingen

We propose a superconducting spin valve based on a Josephson junction with B20-family magnetic metal as a barrier material. Our analysis shows that the states of this element can be switched by reorienting the intrinsic non-collinear magnetization of the spiral magnet. This reorientation modifies long-range spin-triplet correlations and thereby strongly influences the critical Josephson current. Compared to superconducting spin valves proposed earlier, our device has the following advantages: (a) it contains only one barrier layer, which makes it easier to fabricate and control; (b) its ground state is stable, which prevents uncontrolled switching; (c) it is compatible with devices of low-T Josephson electronics. This device may switch between two logical states which exhibit two different values of critical current, or its positive and negative values. I.e. 0-π switch is achievable on a simple Josephson junction.

We present a combined experimental and theoretical study of the mineral atacamite Cu_{2}Cl(OH)_{3}. Density-functional theory yields a Hamiltonian describing anisotropic sawtooth chains with weak 3D connections. Experimentally, we fully characterize the antiferromagnetically ordered state. Magnetic order shows a complex evolution with the magnetic field, while, starting at 31.5 T, we observe a plateaulike magnetization at about M_{sat}/2. Based on complementary theoretical approaches, we show that the latter is unrelated to the known magnetization plateau of a sawtooth chain. Instead, we provide evidence that the magnetization process in atacamite is a field-driven canting of a 3D network of weakly coupled sawtooth chains that form giant moments.

I. Martínez Segura and M. J. Román Alpiste are thanked for their kind assistance during sample preparation and SEM operation, and M. T. Gómez‐Pugnaire and A. Jabaloy for early work on Almirez ophicarbonates. We are grateful to the Sierra Nevada National Park for providing permits for fieldwork and sampling at the Almirez massif. We further acknowledge the editorial handling by D. Whitney and D. Robinson and the reviews of M. Galvez and T. Pettke, whose comments and constructive criticism helped to improve the manuscript. We acknowledge funding from the European Union FP7 Marie‐Curie Initial Training Network ABYSS under REA Grant Agreement no. 608001 in the framework of M.D.M.'s PhD project, the Spanish ‘Agencia Estatal de Investigación’ (AEI) grants no. CGL2016‐75224‐R to V.L.S.‐V and CGL2016‐81085‐R to C.J.G and C.M and grant no. PCIN‐2015‐053 to C.J.G. The ‘Junta de Andalucía’ is also thanked for funding under grants no. RNM‐131, RNM‐374 and P12‐RNM‐3141. C.M. thanks MINECO for financing a Ramón y Cajal fellowship no. RYC‐2012‐11314 and K.H. for a Juan de la Cierva Fellowship no. FPDI‐2013‐16253 and a research contract under grant no. CGL2016‐81085‐R. This work and the research infrastructure at the IACT have received (co)funding from the European Social Fund and the European Regional Development Fund., At sub‐arc depths, the release of carbon from subducting slab lithologies is mostly controlled by fluid released by devolatilization reactions such as dehydration of antigorite (Atg‐) serpentinite to prograde peridotite. Here we investigate carbonate–silicate rocks hosted in Atg‐serpentinite and prograde chlorite (Chl‐) harzburgite in the Milagrosa and Almirez ultramafic massifs of the palaeo‐subducted Nevado‐Filábride Complex (NFC, Betic Cordillera, S. Spain). These massifs provide a unique opportunity to study the stability of carbonate during subduction metamorphism at P–T conditions before and after the dehydration of Atg‐serpentinite in a warm subduction setting. In the Milagrosa massif, carbonate–silicate rocks occur as lenses of Ti‐clinohumite–diopside–calcite marbles, diopside–dolomite marbles and antigorite–diopside–dolomite rocks hosted in clinopyroxene‐bearing Atg‐serpentinite. In Almirez, carbonate–silicate rocks are hosted in Chl‐harzburgite and show a high‐grade assemblage composed of olivine, Ti‐clinohumite, diopside, chlorite, dolomite, calcite, Cr‐ bearing magnetite, pentlandite and rare aragonite inclusions. These NFC carbonate–silicate rocks have variable CaO and CO2 contents at nearly constant Mg/ Si ratio and high Ni and Cr contents, indicating that their protoliths were variable mixtures of serpentine and Ca‐carbonate (i.e., ophicarbonates). Thermodynamic modelling shows that the carbonate–silicate rocks attained peak metamorphic conditions similar to those of their host serpentinite (Milagrosa massif; 550–600°C and 1.0–1.4 GPa) and Chl‐harzburgite (Almirez massif; 1.7–1.9 GPa and 680°C). Microstructures, mineral chemistry and phase relations indicate that the hybrid carbonate–silicate bulk rock compositions formed before prograde metamorphism, likely during seawater hydrothermal alteration, and subsequently underwent subduction metamorphism. In the CaO–MgO–SiO2 ternary, these processes resulted in a compositional variability of NFC serpentinite‐hosted carbonate–silicate rocks along the serpentine‐calcite mixing trend, similar to that observed in serpentinite‐hosted carbonate‐rocks in other palaeo‐subducted metamorphic terranes. Thermodynamic modelling using classical models of binary H2O–CO2 fluids shows that the compositional variability along this binary determines the temperature of the main devolatilization reactions, the fluid composition and the mineral assemblages of reaction products during prograde subduction metamorphism. Thermodynamic modelling considering electrolytic fluids reveals that H2O and molecular CO2 are the main fluid species and charged carbon‐bearing species occur only in minor amounts in equilibrium with carbonate–silicate rocks in warm subduction settings. Consequently, accounting for electrolytic fluids at these conditions slightly increases the solubility of carbon in the fluids compared with predictions by classical binary H2O–CO2 fluids, but does not affect the topology of phase relations in serpentinite‐hosted carbonate‐ rocks. Phase relations, mineral composition and assemblages of Milagrosa and Almirez (meta)‐serpentinite‐hosted carbonate–silicate rocks are consistent with local equilibrium between an infiltrating fluid and the bulk rock composition and indicate a limited role of infiltration‐driven decarbonation. Our study shows natural evidence for the preservation of carbonates in serpentinite‐hosted carbonate–silicate rocks beyond the Atg‐serpentinite breakdown at sub‐arc depths, demonstrating that carbon can be recycled into the deep mantle., Funding from the European Union FP7 Marie‐Curie Initial Training Network ABYSS under REA Grant Agreement no. 608001, Spanish ‘Agencia Estatal de Investigación’ (AEI) grants no. CGL2016‐75224‐R to V.L.S.‐V and CGL2016‐81085‐R to C.J.G and C.M and grant no. PCIN‐2015‐053 to C.J.G, Junta de Andalucía Funding under grants no. RNM‐131, RNM‐374 and P12‐RNM‐3141, MINECO for financing a Ramón y Cajal fellowship no. RYC‐2012‐11314 and K.H. for a Juan de la Cierva Fellowship no. FPDI‐2013‐16253 and a research contract under grant no. CGL2016‐81085‐R

Subduction of serpentinite-hosted carbonate rocks formed during the oceanic stage in the oceanic lithosphere (ophicalcite) or by metasomatism at the slab mantle-wedge interface (hybrid carbonate–talc rocks) constitute important fluxes of carbon in subduction zones. If hosted in the hydrated mantle lithosphere of the slab, these carbonate-rocks may be preserved from the infiltration of fluids produced by prograde metamorphism of the overlying meta-sediments and the hydrated oceanic crust to subarc depths, where they are fluxed by fluids derived from dehydration of their host serpentinite. Because the dissolution of carbonate in aqueous fluids is enhanced at high P and T, fluid-mediated carbon release at subarc depth is critical to understand the global carbon balance and magnitude of carbon fluxes from the subducting plate into the deep mantle. This contribution presents thermodynamic modelling —using the implementation of the DEW aqueous database in Perple_X— of prograde devolatilization reactions (solid = fluid + solid) and infiltration-driven devolatilization reactions (external fluid + solid = fluid + solid) of serpentinite-hosted carbonate rocks. In line with previous studies of prograde devolatilization of carbon-bearing oceanic crust, our models show that, in warm and cold subductions zones, the carbon released into fluids produced by prograde devolatilization reactions of meta-ophicalcite and carbonate-talc rocks is limited even if electrolytic complexing in the fluid phase is taken into account. Therefore, serpentinite-hosted meta-carbonate rocks are likely to be preserved to subarc depths, where they undergo infiltration-driven devolatilization by fluids derived from Atg-serpentinite dehydration. At the P–T conditions of Atg-breakdown in cold to warm subduction zones, our models of infiltration-driven devolatilization of meta-ophicalcite and carbonate-talc rocks indicate that carbon release is accompanied by significant Ca loss, particularly at high pressures (P>3.5 GPa), due to the high concentration of CaHCO+3 in the fluid. The carbon solubility in fluids equilibrated with meta-ophicalcite and carbonate–talc rocks is markedly higher than for pure aragonite. Mass balance considerations combined with the parameterization of the P–T conditions of Atg-serpentinite dehydration as a function of the thermal parameter of subduction zones allow us to investigate the carbon loss caused by infiltration of serpentinite dehydration fluids. Unlike the dissolution of pure CaCO, carbonate dissolution in serpentinite-hosted meta-carbonate rocks is highest at the slab surface of warm subduction zones and lowest at Moho depths of cold subduction zones, where Atg-serpentinite dehydration occurs at greater depths. Carbon in subducted meta-ophicalcite —with thicknesses of up to 70 m typically found in oceanic ophicalcite— will be preserved beyond the subarc depths of cold and hot subduction zones, and recycled into the deep mantle as carbonate-garnet-clinopyroxene-olivine rocks. At the subarc depths of most subduction zone regimes, infiltration-driven devolatilization of subducted carbonate-talc rocks is a highly efficient decarbonation mechanism transforming these rocks into carbon-free orthopyroxenite., Research leading to these results is part of the Marie Curie Action, Initial Training Network “ABYSS”, funded by the Seventh Framework Programme of the European Union under REA Grant Agreement no. 608001, and is part of M.M.'s Ph.D. Thesis. C.J.G. and V.L.S.-V. acknowledge funding from the “Spanish Ministry of Economy, Industry, and Competitiveness (MINECO)” grants no. CGL2016-75224-R and CGL2016-81085-R, and from the “Junta de Andalucía” research group grants RNM-131 and RNM-374. The present research and the research infrastructures at the IACT have received (co)funding from the European Social Fund (ESF) and the European Regional Development Fund (ERDF).

The mantle section of the Advocate ophiolite (Newfoundland, Canada) contains unique outcrops of listvenite (magnesite-quartz), antigorite- and quartz-bearing talc-magnesite rock, and carbonated antigorite-serpentinite. This lithological sequence records the sequential carbonation of serpentinite by CO2-rich hydrothermal fluids. High Cr and Ni contents and preservation of Cr-spinel with a composition similar to that of Atg-serpentinite (molar Mg/Mg + Fe = 0.50–0.65; Cr/Cr + Al = 0.50–0.70), show that the Advocate listvenite and talc-magnesite rocks formed by carbonation of variably serpentinized mantle harzburgite. Replacement of lizardite by magnesite coeval with the breakdown of lizardite to antigorite + brucite and the lack of prograde olivine and magnetite in antigorite serpentinite and talc-magnesite rocks constrain the temperature of carbonation between c. 280 °C and 420 °C. Thermodynamic modelling of carbonation of serpentinite at 300 °C and 0.2–0.5 GPa accounts for the sequence of carbonated rocks in the Advocate complex. Phase relations and petrological observations indicate that the aqueous aSiO2 and aCO2 of the infiltrating CO2-rich fluid were buffered at the Atg-Tlc-Mgs and Qtz-Tlc-Mgs pseudo-invariant points, forming dominantly three-phase rocks by variable extents of carbonation at these pseudo-invariant points. Listvenites formed at large fluid-rock ratio when quartz became saturated in the fluid and precipitated along magnesite grain boundaries and in variably sized tensional veins. The whole rock Fe3+/Fetotal ratio of the Advocate carbonate-bearing sequence decreases with increasing whole rock carbon content, from 0.65–0.80 in brucite-bearing antigorite serpentinite to 0.10–0.30 in talc-magnesite rocks and listvenite. The whole rock iron reduction is associated with an increase in the ferrous iron content of magnesite and the formation of hematite and goethite, indicating a concomitant increase of the fluid oxygen fugacity. The sequence of carbonation reactions is uniquely preserved in three main growth zones characteristic of listvenite magnesite: (i) an inner zone of magnetite-bearing, Fe-poor, Mn-bearing magnesite formed by carbonation of lizardite, brucite and olivine from Atg-serpentinite; (ii) an outer zone of Fe-rich magnesite formed by carbonation of antigorite and in equilibrium with Fe-poor talc; and (iii) an outermost rim of Fe-poor magnesite formed by carbonation of talc. We propose that carbonation of the Advocate serpentinized mantle harzburgite occurred in a supra-subduction upper plate ophiolite by fluxing of slab-derived, CO2-rich fluids channelled along deep faults at the onset of accretion of the forearc basin (c. 300 °C

The first point of our body’s contact with tactile stimuli (innocuous and noxious) is the epidermis, the outermost layer of skin that is largely composed of keratinocytes. Here, we sought to define the role that keratinocytes play in touch sensation in vivo and ex vivo. We show that optogenetic inhibition of keratinocytes decreases behavioral and cellular mechanosensitivity. These processes are inherently mediated by ATP signaling, as demonstrated by complementary cutaneous ATP release and degradation experiments. Specific deletion of P2X4 receptors in sensory neurons markedly decreases behavioral and primary afferent mechanical sensitivity, thus positioning keratinocyte-released ATP to sensory neuron P2X4 signaling as a critical component of baseline mammalian tactile sensation. These experiments lay a vital foundation for subsequent studies into the dysfunctional signaling that occurs in cutaneous pain and itch disorders, and ultimately, the development of novel topical therapeutics for these conditions., eLife digest The skin is the largest sensory organ of the body, and the first point of contact with the outside world. Whether it is being pinched or caressed, the skin’s sense of touch informs organisms about their surroundings and allows them to react appropriately. Nerve cells present in the skin capture information about touch and transmit it to the brain where it is decoded. However, there are many other types of cells in the skin besides nerve cells. The role that these other skin cells play in perceiving non-painful and painful touch is still unclear. Moehring et al. now report how the skin cells that form 95% of the most outer layer of the skin are involved in detecting touch. In mutant mice whose cells can be ‘switched off’ by a certain light, artificially deactivating these cells makes the animals less able to respond to tactile stimuli. Further experiments show that when pressure is applied onto the skin, the surface skin cells release a chemical messenger, which then binds specifically to the nerve cells. When the messaging molecule is experimentally destroyed or prevented from attaching to the nerve cell, the mice react less to non-painful and painful touch. This means the cells at the surface of the skin detect tactile signals from the environment and then communicate this information to the nerve cells, where it is taken to the brain. Disrupted communication between the cells in the outer layer of the skin and the nerve cells is found in painful and itchy skin conditions such as eczema and psoriasis. Knowing how these two types of cells normally work together may help with finding new pain and itch treatments for these skin disorders.

Inflammasomes are cytosolic receptors of the innate immune system that are responsible for activation and secretion of the proinflammatory cytokine interleukin-1β (IL-1β) where IL-1β is known to cause pain by directly acting on sensory neurons. Specifically, IL-1β is known to cause peripheral sensitization to mechanical stimuli in models of inflammatory and neuropathic pain. Of the multiple inflammasomes, the NOD-like receptor protein 3 (NLRP3) inflammasome is activated by endogenous molecules that are released as a result of tissue injury and thus is ideally positioned to produce the majority of postoperative IL-1β. Therefore, we aimed to uncover the mechanism by which NLRP3 modifies postoperative pain in males and females. Male mice lacking NLRP3 recovered from incisional surgery significantly faster at the behavioral and primary afferent levels and exhibited less peri-incisional inflammation than mice expressing NLRP3 (WT). In contrast, female mice lacking NLRP3 displayed only attenuated postoperative mechanical hypersensitivity and peri-incisional inflammation was unchanged compared to WT females. Furthermore, sensory neuron-specific deletion of NLRP3 revealed that, in males, NLRP3 expressed in both sensory neurons and non-neuronal cells drives postoperative pain whereas, in females, only sensory neuron NLRP3 contributes. This is the first evidence for a direct role for NLRP3 and inflammasome-mediated sex differences in postoperative pain.

Pain is the leading cause of hospitalization for patients with sickle cell disease (SCD). Currently, opioids are the main therapy for both chronic “steady state” SCD pain and acute pain that results from vaso-occlusive crises. However, opioids are often ineffective at fully alleviating pain, are associated with unwanted side effects, and do not target the underlying pain mechanism. Thus, new pain therapies are desperately needed for those suffering from SCD pain. Recent quantitative sensory testing in patients and electrophysiological studies in mouse models have identified a neuropathic component of SCD pain; SCD patients and mice exhibit robust mechanical and cold hypersensitivity that is further exacerbated following a vaso-occlusive event. As a result, we tested the analgesic effects of gabapentin, one of the first line therapies for neuropathic pain, in male and female transgenic SCD mice. A single dose of gabapentin (30 mg/kg) alleviated steady state mechanical hypersensitivity in the hindpaw but had no effect on steady state cold hypersensitivity, deep muscle pain, or facial mechanical hypersensitivity. In a separate experiment, gabapentin was administered daily for 4 weeks to model neuropathic pain patient therapy. This chronic administration did not alleviate steady state mechanical hypersensitivity, cold hypersensitivity, or deep muscle pain in SCD mice. However, chronic gabapentin treatment did prevent hypoxia-induced exacerbation of mechanical hypersensitivity in SCD mice. Notably, a single dose of gabapentin administered shortly after hypoxia treatment alleviated ischemia-induced mechanical hypersensitivity to a greater extent than chronic gabapentin treatment. Finally, the effects of gabapentin on spontaneous pain-like behaviors and spontaneous neuronal activity were assessed using conditioned place preference and ex vivo skin nerve recordings respectively. Collectively, these data demonstrate that the drivers of acute vaso-occlusive crisis pain and chronic mechanical hypersensitivity may be caused by different factors, the former of which may be alleviated by gabapentin treatment.

We developed a new trauma model to examinate the connection between trauma and laboratory findings as trauma response in an animal experiment. A transverse mechanism by impact force produced C2 and C3 fractures with 1° open soft tissue injury in hind leg of sheep. Because there are no invasive preparations necessary the laboratory findings are only responsed to the trauma. Also the injury of bone and soft tissue is constant to examinate the operative treatment of defect fractures.

The electronic structure of benzene adsorbed on single-domain Ge(100)-(2×1) and on a single-domain Ge monolayer grown on Si(100)-(2×1) has been investigated by angle-resolved ultraviolet photoemiss...

The continuously changing polar cytoplasmic organization during initiation and tip growth of root hairs is reflected by a dynamic redistribution of cytoskeletal elements. The small G-actin binding protein, profilin, which is known to be a widely expressed, potent regulator of actin dynamics, was specifically localized at the tip of root hairs and co-distributed with a diffusely fluorescing apical cap of actin, but not with subapical actin microfilament (MF) bundles. Profilin and actin caps were present exclusively in the bulge of outgrowing root hairs and at the apex of elongating root hairs; both disappeared when tip growth terminated, indicating a tip-growth mechanism that involves profilin-actin interactions for the delivery and localized exocytosis of secretory vesicles. Phosphatidylinositol-4,5-bisphosphate (PIP(2)), a ligand of profilin, was localized almost exclusively in the bulge and, subsequently, formed a weak tip-to-base gradient in the elongating root hairs. When tip growth was eliminated by the MF-disrupting inhibitor cytochalasin D, the apical profilin and the actin fluorescence were lost. Mastoparan, which is known to affect the PIP(2) cycle, probably by stimulating phospholipases, caused the formation of a meshwork of distinct actin MFs replacing the diffuse apical actin cap and, concomittantly, tip growth stopped. This suggests that mastoparan interferes with the PIP(2)-regulated profilin-actin interactions and hence disturbs conditions indispensable for the maintenance of tip growth in root hairs.

The post-Carboniferous crustal evolution of the German Continental Deep Drilling Program (KTB) area, as summarized in this paper, could not be predicted from surface observations: deep drilling was essential for its revelation, The most conspicuous and unexpected feature discovered in the drill hole is the absence of marked gradients with respect to the pre-Carboniferous record, There are no depth-related differences in K-Ar cooling ages of hornblende and white mica, in petrology or in lithology, All metamorphic rocks encountered, both at the surface as well as in the drill hole down to 9100 m depth, were below 300 degrees C from the Carboniferous onward. The late to post-Carboniferous deformation is essentially confined to several fault zones, A major fault zone encountered in the drill hole at 7000 m depth is linked by a prominent seismic reflector to the Franconian Lineament, the surface boundary between Variscan basement and Mesozoic cover, This fault zone probably formed in the late Paleozoic and reactivated as a reverse fault in the Mesozoic. Two important episodes of NE-SW directed shortening by movements along reverse faults took place in the early Triassic and in the late Cretaceous, as indicated by the distribution of apatite and titanite fission-track ages, the sericite K-Ar ages of fault rocks, and the sedimentary record in the adjacent basins, Upper crustal slices were detached at a specific level, corresponding to the approximate position of the brittle-ductile transition in post-Variscan times, and form an antiformal stack that was penetrated by the KTB throughout its entire depth range.