Chiral superconductors are a class of unconventional superconductors that host topologically protected chiral Majorana fermions at interfaces and domain walls1–3, quasiparticles4–6 that could serve ...as a platform for topological quantum computing7. Here we show that, in analogy to a qubit, the out-of-equilibrium superconducting state in such materials can be described by a Bloch vector and predict that they can be controlled on ultrafast timescales. The all-optical control mechanism is universal, permitting arbitrary rotations of the order parameter, and can induce a dynamical change of handedness of the condensate. It relies on transient breaking of crystal symmetries via choice of pulse polarization to enable arbitrary rotations of the Bloch vector. The mechanism extends to ultrafast timescales and the engineered state persists after the pump is switched off. We predict that these phenomena should appear in graphene8–10 or magic-angle twisted bilayer graphene11–14, as well as Sr2RuO4 (refs. 15,16). Furthermore, we show that chiral superconductivity can be detected in time-resolved pump–probe measurements. This paves the way towards a robust mechanism for ultrafast control and measurement of chirally ordered phases and Majorana modes.This study presents a proposal for an all-optical method for manipulating chiral superconductors. Light pulses can switch the handedness of the chirality, potentially enabling controlled local writing of domain walls and associated Majorana modes.
In the 60 years since the invention of the laser, the scientific community has developed numerous fields of research based on these bright, coherent light sources, including the areas of imaging, ...spectroscopy, materials processing and communications. Ultrafast spectroscopy and imaging techniques are at the forefront of research into the light-matter interaction at the shortest times accessible to experiments, ranging from a few attoseconds to nanoseconds. Light pulses provide a crucial probe of the dynamical motion of charges, spins, and atoms on picosecond, femtosecond, and down to attosecond timescales, none of which are accessible even with the fastest electronic devices. Furthermore, strong light pulses can drive materials into unusual phases, with exotic properties. In this roadmap we describe the current state-of-the-art in experimental and theoretical studies of condensed matter using ultrafast probes. In each contribution, the authors also use their extensive knowledge to highlight challenges and predict future trends.
So far, laser control of solids has been mainly discussed in the context of strong classical nonlinear light-matter coupling in a pump-probe framework. Here, we propose a quantum-electrodynamical ...setting to address the coupling of a low-dimensional quantum material to quantized electromagnetic fields in quantum cavities. Using a protoypical model system describing FeSe/SrTiO
with electron-phonon long-range forward scattering, we study how the formation of phonon polaritons at the two-dimensional interface of the material modifies effective couplings and superconducting properties in a Migdal-Eliashberg simulation. We find that through highly polarizable dipolar phonons, large cavity-enhanced electron-phonon couplings are possible, but superconductivity is not enhanced for the forward-scattering pairing mechanism due to the interplay between coupling enhancement and mode softening. Our results demonstrate that quantum cavities enable the engineering of fundamental couplings in solids, paving the way for unprecedented control of material properties.
Fertility preservation is an urgent challenge in the transplant setting. A panel of transplanters and fertility specialists within the Pediatric Diseases Working Party of the European Society for ...Blood and Marrow Transplantation (EBMT) and the International BFM Study Group provides specific guidelines. Patients and families should be informed of possible gender- and age-specific cryopreservation strategies that should be tailored according to the underlying disease, clinical condition and previous exposure to chemotherapy. Semen collection should be routinely offered to all postpubertal boys at the diagnosis of any disease requiring therapy that could potentially impair fertility. Testicular tissue collection might be offered to postpubertal boys; nevertheless, its use has been unsuccessful to date. Oocyte collection after hormonal hyperstimulation should be offered to postpubertal girls facing gonadotoxic therapies that could be delayed for the 2 weeks required for the procedure. Ovarian tissue collection could be offered to pre-/post-pubertal girls. Pregnancies have been reported after postpubertal ovarian tissue reimplantation; however, to date, no pregnancy has been reported after the reimplantation of prepubertal ovarian tissue or in vitro maturation of pre-/post-pubertal ovarian tissue. Possible future advances in reproductive medicine could change this scenario. Health authorities should prioritize fertility preservation projects in pediatric transplantation to improve patient care and quality of life.
Highlights • The small molecule inhibitor of the inflammasome, MC950, attenuates Aβ+LPS-induced inflammasome activation in microglia. • It increases phagocytosis of Aβ by microglia in vitro. • Oral ...administration of MC950, reduces Aβ accumulation in APP/PS1 mice. • This is accompanied by improved cognitive function and decreased neuroinflammation.
The trend towards miniaturization has increased dramatically over the last decade, especially within the fields concerned with bioengineering, microelectronics, and aerospace. Micromillin8 is among ...the principal manu- facturing processes which have allowed the development of components possessing micrometric dimensions, being used to the manufacture of both forming tools and the final product. The aim of this work is to present the principal aspects related to this technology, with emphasis on the work material requirements, tool ma- terials and geometry, cutting forces and temperature, quality of the finished product, process modelling and monitoring and machine tool requirements. It can be noticed that size effect possesses a relevant role with regard to the selection of both work material （grain size） and tooling （edge radius）. Low forces and temper- ature are recorded during micromillin8, however, the specific cutting force may reach high values because of the ploughing effect observed as the uncut chip thickness is reduced. Finally, burr formation is the principal concern with regard to the quality of the finished part.
Gallium oxide (Ga2O3) thin films were produced by sputter deposition by varying the substrate temperature (T s) in a wide range (T s = 25–800 °C). The structural characteristics and optical ...properties of Ga2O3 films were evaluated using X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectrometry (EDS), Rutherford backscattering spectrometry (RBS), and spectrophotometric measurements. The effect of growth temperature is significant on the chemistry, crystal structure, and morphology of Ga2O3 films. XRD and SEM analyses indicate that the Ga2O3 films grown at lower temperatures were amorphous, while those grown at T s ≥ 500 °C were nanocrystalline. RBS measurements indicate the well-maintained stoichiometry of Ga2O3 films at T s = 300–800 °C. The spectral transmission of the films increased with increasing temperature. The band gap of the films varied from 4.96 to 5.17 eV for a variation in T s in the range 25–800 °C. A relationship between microstructure and optical property is discussed.
The effects of dietary administration of probiotic Pdp11, a bacterial probiotic strain from the Alteromonadaceae family, on growth and stress tolerance to high stocking density was analyzed in ...juvenile gilthead sea bream
Sparus auratus. In the first trial, juvenile specimens were fed during 116
days with control feed or diets supplemented with Pdp11, and growth, serum immunological parameters as well as plasmatic, hepatic and muscular metabolic parameters were assessed. Growth performance improved in group receiving probiotic compared to control group. No differences were observed for the assessed immunological or metabolic parameters. In the second trial, specimens from both groups from the first experiment were submitted to the following conditions for 15
days: i) group fed with control food and either under low density (3
kg/m
3), or high density (30
kg/m
3) and ii) group fed with probiotic supplemented feed and either under low density, or high density. Our results indicated that administration of probiotic Pdp11 in the diet promoted growth and improved stress tolerance under high stocking density, suggesting its use will be beneficial for the aquaculture industry of this species.
Rapidly rotating Rayleigh-Bénard convection is studied using an asymptotically reduced equation set valid in the limit of low Rossby numbers. Four distinct dynamical regimes are identified: a ...disordered cellular regime near threshold, a regime of weakly interacting convective Taylor columns at larger Rayleigh numbers, followed for yet larger Rayleigh numbers by a breakdown of the convective Taylor columns into a disordered plume regime characterized by reduced efficiency and finally by geostrophic turbulence. The transitions are quantified by examining the properties of the horizontally and temporally averaged temperature and thermal dissipation rate. The maximum of the thermal dissipation rate is used to define the width of the thermal boundary layer. In contrast to the non-rotating Rayleigh-Bénard convection, the temperature drop across this layer decreases monotonically with increasing Rayleigh number and does not saturate. The breakdown of the convective Taylor column regime is attributed to the onset of convective instability of the thermal boundary layer and confirmed using the explicit linear stability analysis. Horizontal spectra of the vorticity, vertical velocity and temperature fluctuations are computed and their evolution with time is elucidated. A large-scale barotropic mode evolves from random initial conditions on an extremely long time scale and leads to continued evolution of the nominally saturated Nusselt number and its variance over very long times. The results are used to provide insights into the dynamics of rapidly rotating convection outside the asymptotic regime described by the reduced equations.
Growing evidence shows that mechanisms controlling CNS plasticity extend beyond the synapse and that alterations in myelin can modify conduction velocity, leading to changes in neural circuitry. ...Although it is widely accepted that newly generated oligodendrocytes (OLs) produce myelin in the adult CNS, the contribution of preexisting OLs to functional myelin remodeling is not known. Here, we show that sustained activation of extracellular signal-regulated kinases 1 and 2 (ERK1/2) in preexisting OLs of adult mice is sufficient to drive increased myelin thickness, faster conduction speeds, and enhanced hippocampal-dependent emotional learning. Although preexisting OLs do not normally contribute to remyelination, we show that sustained activation of ERK1/2 renders them able to do so. These data suggest that strategies designed to push mature OLs to reinitiate myelination may be beneficial both for enhancing remyelination in demyelinating diseases and for increasing neural plasticity in the adult CNS.
Myelin is a crucial regulator of CNS plasticity, function, and repair. Although it is generally accepted that new myelin production in the adult CNS is initiated by newly generated oligodendrocytes (OLs), great interest remains in additionally driving mature preexisting OLs to make myelin. The ability to induce myelination by the larger population of preexisting OLs carries the potential for enhanced remyelination in demyelinating diseases and increased neural plasticity in the adult CNS. Here, we show that sustained activation of the extracellular signal-regulated kinases 1 and 2 (ERK1/2) signaling pathway is sufficient to drive mature OLs in the adult mouse CNS to reinitiate myelination, leading to new myelin wraps and functional changes.
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