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While many organisms synthesize robust skeletal composites consisting of spatially discrete organic and mineral (ceramic) phases, the intrinsic mechanical properties of the mineral phases are poorly understood. Using the shell of the marine bivalve Atrina rigida as a model system, and through a combination of multiscale structural and mechanical characterization in conjunction with theoretical and computational modeling, we uncover the underlying mechanical roles of a ubiquitous structural motif in biogenic calcite, their nanoscopic intracrystalline defects. These nanoscopic defects not only suppress the soft yielding of pure calcite through the classical precipitation strengthening mechanism, but also enhance energy dissipation through controlled nano- and micro-fracture, where the defects’ size, geometry, orientation, and distribution facilitate and guide crack initialization and propagation. These nano- and micro-scale cracks are further confined by larger scale intercrystalline organic interfaces, enabling further improved damage tolerance. Biominerals are nanocomposites that often incorporate nanoscopic defects such as organic inclusions within the mineral matrix. Here, the authors report on an experimental and computational study into the effects of intracrystalline defects on the intrinsic mechanical behaviour of biominerals.

Synchrotron radiation provides the necessary spatial and temporal resolution for non‐invasive operando studies of dynamic processes under complex environmental conditions. Here a new environmental cell for simultaneous in situ dynamic X‐ray imaging and measuring acoustic properties of geological samples is presented. The primary purpose of this cell is to study gas‐hydrate formation in porous geo‐materials and its influence on their acoustic properties. The cell is designed for cylindrical samples of 9 mm in diameter, confining and pore pressures up to 12 MPa, and temperatures from −20°C to room temperature. The cell is portable and can be easily assembled and operated at different X‐ray sources. This cell enables a wide range of experiments studying physical/chemical processes in the Earth subsurface that change the mechanical properties of rocks (geochemical reactions, phase transitions, etc.). A new environmental cell for simultaneous in situ dynamic X‐ray imaging and measuring acoustic properties of geological samples is presented. The cell helps studying physical/chemical processes in geomaterials and their influence on the mechanical properties.

The authors report that the chloride channel CLC-3 colocalizes with the vesicular GABA transporter VGAT in the CA1 region of the hippocampus, where it affected Cl − -induced acidification of synaptic vesicles. Clcn3 −/− animals showed a decrement in inhibitory transmission, suggesting a decrease in neurotransmitter loading of synaptic vesicles. The absence of the chloride channel CLC-3 in Clcn3 −/− mice results in hippocampal degeneration with a distinct temporal-spatial sequence that resembles neuronal loss in temporal lobe epilepsy. We examined how the loss of CLC-3 might affect GABAergic synaptic transmission in the hippocampus. An electrophysiological study of synaptic function in hippocampal slices taken from Clcn3 −/− mice before the onset of neurodegeneration revealed a substantial decrease in the amplitude and frequency of miniature inhibitory postsynaptic currents compared with those in wild-type slices. We found that CLC-3 colocalized with the vesicular GABA transporter VGAT in the CA1 region of the hippocampus. Acidification of inhibitory synaptic vesicles induced by Cl − showed a marked dependence on CLC-3 expression. The decrease in inhibitory transmission in Clcn3 −/− mice suggests that the neurotransmitter loading of synaptic vesicles was reduced, which we attribute to defective vesicular acidification. Our observations extend the role of Cl − in inhibitory transmission from that of a postsynaptic permeant species to a presynaptic regulatory element.

We present the results of dynamic in-situ 3D X-ray imaging of methane hydrates microstructure during methane hydrate formation and decomposition in sand samples. Short scanning times and high resolution provided by synchrotron X-rays allowed for better understanding of water movement and different types of gas-hydrate formation. Complementing previous observations, we conclude that the process of gas-hydrate formation is accompanied by the water movements caused by cryogenic water suction that happens in short sequences with longer equilibrium states in between (when the water is immobile). Based on the 3D microstructure we identified two types of gas-hydrate formation: (i) into the gas pockets and (ii) inside water volumes. During the decomposition in the self-preservation mode (pressure drop at negative temperatures) the latter remains more stable compared to the hydrate formed as growing into the gas pocket. This means that the history of the gas-hydrate formation influences its behaviour at the decomposition stage (e.g. gas-hydrate production).

Defects in the innate immune system in the lung with attendant bacterial infections contribute to lung tissue damage, respiratory insufficiency, and ultimately death in the pathogenesis of cystic fibrosis (CF). Professional phagocytes, including alveolarmacrophages (AMs), have specialized pathways that ensure efficient killing of pathogens in phagosomes. Phagosomal acidification facilitates the optimal functioning of degradative enzymes, ultimately contributing to bacterial killing. Generation of low organellar pH is primarily driven by the V-ATPases, proton pumps that use cytoplasmic ATP to load H⁺ into the organelle. Critical to phagosomal acidification are various channels derived from the plasma membrane, including the anion channel cystic fibrosis transmembrane conductance regulator, which shunt the transmembrane potential generated by movement of protons. Here we show that the transient receptor potential canonical-6 (TRPC6) calcium-permeable channel in the AMalso functions to shunt the transmembrane potential generated by proton pumping and is capable of restoring microbicidal function to compromised AMs in CF and enhancement of function in non-CF cells. TRPC6 channel activity is enhanced via translocation to the cell surface (and then ultimately to the phagosome during phagocytosis) in response to G-protein signaling activated by the small molecule (R)-roscovitine and its derivatives. These data show that enhancing vesicular insertion of the TRPC6 channel to the plasma membrane may represent a general mechanism for restoring phagosome activity in conditions, where it is lost or impaired.

Cell therapy remains a promising approach for the treatment of cardiovascular diseases. In this regard, the contemporary trend is the development of methods to overcome low cell viability and enhance their regenerative potential. In the present study, we evaluated the therapeutic potential of gene-modified adipose-derived stromal cells (ADSC) that overexpress hepatocyte growth factor (HGF) in a mice hind limb ischemia model. Angiogenic and neuroprotective effects were assessed following ADSC transplantation in suspension or in the form of cell sheet. We found superior blood flow restoration, tissue vascularization and innervation, and fibrosis reduction after transplantation of HGF-producing ADSC sheet compared to other groups. We suggest that the observed effects are determined by pleiotropic effects of HGF, along with the multifactorial paracrine action of ADSC which remain viable and functionally active within the engineered cell construct. Thus, we demonstrated the high therapeutic potential of the utilized approach for skeletal muscle recovery after ischemic damage associated with complex tissue degenerative effects.

Snow cover plays a major role in the climate, hydrological and ecological systems of the Arctic and other regions through its influence on the surface energy balance (e.g. reflectivity), water balance (e.g. water storage and release), thermal regimes (e.g. insulation), vegetation and trace gas fluxes. Feedbacks to the climate system have global consequences. The livelihoods and well-being of Arctic residents and many services for the wider population depend on snow conditions so changes have important consequences. Already, changing snow conditions, particularly reduced summer soil moisture, winter thaw events and rain-on-snow conditions have negatively affected commercial forestry, reindeer herding, some wild animal populations and vegetation. Reductions in snow cover are also adversely impacting indigenous peoples' access to traditional foods with negative impacts on human health and well-being. However, there are likely to be some benefits from a changing Arctic snow regime such as more even run-off from melting snow that favours hydropower operations.

For revealing the peculiarities of the drug–drug interaction of rivaroxaban (substrate CYP3A4 and P-gp) and calcium channel blockers (CCBs) (verapamil – inhibitor CYP3A4 and P-gp and amlodipine – substrate CYP3A4) in patients 80 years and older with nonvalvular atrial fibrillation (NAF) we studied 128 patients.All patients were divided into groups depending on the therapy taken: the 1st – rivaroxaban + amlodipine (n=51), the 2nd – rivaroxaban + verapamil (n=30), the control group – rivaroxaban without CCBs (n=47). A trough steady-state plasma concentration (Cmin,ss) of rivaroxaban, prothrombin time (PT) in the blood plasma and the event of clinically relevant non-major (CRNM) bleeding were assessed for each patient.Patient in group 2 had higher Cmin,ss of rivaroxaban, PT and CRNM than subjects in the control group (Me 73.8 [50.6–108.8] ng/mL vs. 40.5 [25.6–74.3] ng/mL; Me 14.8 [13.4–17.3] s vs. 13.8 [12.6–14.4] s; 34% vs. 13%, respectively, p<0.05 for all). When compared, the PT and complication rate in group 1 with the control group Cmin,ss of rivaroxaban were practically the same (p>0.05 for all).In patients ≥80 years with NAF, the use of rivaroxaban in combination with verapamil may not be safe and can lead to CRNM bleeding.

Defects in the innate immune system in the lung with attendant bacterial infections contribute to lung tissue damage, respiratory insufficiency, and ultimately death in the pathogenesis of cystic fibrosis (CF). Professional phagocytes, including alveolar macrophages (AMs), have specialized pathways that ensure efficient killing of pathogens in phagosomes. Phagosomal acidification facilitates the optimal functioning of degradative enzymes, ultimately contributing to bacterial killing. Generation of low organellar pH is primarily driven by the V-ATPases, proton pumps that use cytoplasmic ATP to load H+ into the organelle. Critical to phagosomal acidification are various channels derived from the plasma membrane, including the anion channel cystic fibrosis transmembrane conductance regulator, which shunt the transmembrane potential generated by movement of protons. Here we show that the transient receptor potential canonical-6 (TRPC6) calcium-permeable channel in the AM also functions to shunt the transmembrane potential generated by proton pumping and is capable of restoring microbicidal function to compromised AMs in CF and enhancement of function in non-CF cells. TRPC6 channel activity is enhanced via translocation to the cell surface (and then ultimately to the phagosome during phagocytosis) in response to G-protein signaling activated by the small molecule (R)-roscovitine and its derivatives. These data show that enhancing vesicular insertion of the TRPC6 channel to the plasma membrane may represent a general mechanism for restoring phagosome activity in conditions, where it is lost or impaired.

Solid-state batteries (SSBs) with silicon anodes could enable improved safety and energy density compared to lithium-ion batteries. However, degradation arising from the massive volumetric changes of silicon anodes during cycling are not well understood in solid-state systems. Here, we use operando X-ray computed microtomography to reveal micro-to-macro-scale chemo-mechanical degradation processes of silicon anodes in SSBs. Mud-type channel cracks driven by biaxial tensile stress form across the electrode during delithiation. We also find detrimental cracks at the silicon/solid electrolyte interface that form due to local reaction competition between neighboring domains of different sizes. Continuum phase-field damage modeling quantifies stress-driven channel cracking and shows that the lithiated silicon stress state is critical for determining the extent of interfacial fracture. This work reveals novel mechanisms that govern SSBs compared to conventional lithium-ion batteries and provides guidelines for engineering chemo-mechanically resilient electrodes for high-energy batteries.