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Optimising lithium lanthanum cerate garnet ceramic electrolytes for fast lithium-ion conduction
No full textThe garnet-type electrolytes are promising for solid-state lithium-metal batteries, while it is still challenging to realize fast lithium-ion conduction with moderate sintering process. To solve the problem, we proposed a novel cerium (Ce)-based cubic garnet electrolyte – Li6.25La3Ce1.25Ta0.75O12 (LLCTO-0.75). The Ta5+ doping of the tetragonal Li7La3Ce2O12 (LLCO) results in a stable cubic phase at room temperature, whilst the presence of Ce4+ is associated with enlarging lattice parameters to facilitate lithium-ion migration and promoting sintering. As a result, the LLCTO-0.75 achieves a dense ceramic microstructure with only 30 min sintering at 1150 °C, and an outstanding lithium-ion conductivity of 1.09 mS cm−1 at 30 °C. Benefiting from a small Li/LLCTO-0.75 interfacial resistance of 52.8 Ω cm2 at 30 °C, the Li-Li symmetric cell cycles for over 700 h without short circuit, and the quasi-solid state LiFePO4/LLCTO 0.75/Li battery delivers a satisfying specific capacity of 127.0 mAh g−1 after 300 cycles. This work provides new insights into the development of practical solid-state oxide electrolytes for safe high-energy batteries
Single-cycle parainfluenza virus type 5 vectors for producing recombinant proteins, including a humanized anti-V5 tag antibody
No full textParainfluenza virus type 5 (PIV5) can cause either persistent or acute/lytic infections in a wide range of mammalian tissue culture cells. Here, we have generated PIV5 fusion (F)-expressing helper cell lines that support the replication of F-deleted viruses. As proof of the principle that F-deleted single-cycle infectious viruses can be used as safe and efficient expression vectors, we have cloned and expressed a humanized (Hu) version of the mouse anti-V5 tag antibody (clone SV5-Pk1). We show that multiple different cell lines can be infected and express high levels of the Hu anti-V5 antibody, with Chinese hamster ovary cells expressing 20–50 mg l−1 after 5 days when cells were grown to a density of ~1×106 cells per millilitre at the time of infection. We suggest that PIV5-based vectors may be further developed to produce recombinant proteins both in vitro and in vivo
Magnetic susceptibility cyclostratigraphy of the lower Schwarzrand Subgroup in southern Namibia refines temporal calibration of late Ediacaran bilaterian radiation
No full textThe Nama Group in southern Namibia captures one of the best-preserved records of the last ∼10 million years of the Ediacaran Period, recording pivotal changes to Earth's biosphere and oceans. Within the Nama Group, the lower Schwarzrand Subgroup preserves early complex bilaterian trace fossils, but uncertainties surrounding the ages of their first occurrences hinder global correlation and the understanding of the rates at which critical biological changes occurred. This study presents magnetic susceptibility cyclostratigraphy of a recently acquired drill core that covers the Nudaus Formation and Nasep Member within the lower Schwarzrand Subgroup. Spectral analysis reveals a hierarchy of orbital cycles that could be responsible for the repeating depositional sequences at various length scales in the Schwarzrand Subgroup. Matching the wavelengths of the orbital cycles to their expected periodicities, we established sedimentation rates throughout the stratigraphy. Utilizing available U[sbnd]Pb ages from correlative outcrop sections and the sedimentation rates from cyclostratigraphy, we refine the age-depth model for the lower Schwarzrand Subgroup. Our new age-depth model places tighter temporal constraints on the first appearances of complex trace fossils, thus constraining the earliest major radiation of bilaterian metazoans and contributing to a better-calibrated chronostratigraphy of the terminal Ediacaran Period.</p
HORUS: multimodal large language models framework for video retrieval at VBS 2025
No full textIn the dynamic field of video retrieval, precise and effective search methods are crucial for managing complex datasets. We present HORUS, a novel approach based on multimodal Large Language Models (mLLMs) that advances video retrieval capabilities through two key innovations: (1) advanced multi-modal feature aggregation, integrating text-to-image search with CLIP, free-text search from captions generated by Video-LLaMA2, and visual features from Video-LLaMA to capture temporal dynamics; and (2) GPT-based query expansion, combined with an advanced filter, addresses issues with low-quality open-ended text queries and refines item searches based on type and location within a scene. This work provides cutting-edge solutions for the VBS 2025 challenge and offers valuable insights into enhancing video search techniques
Gl 725A b:a potential super-Earth detected with SOPHIE and SPIRou in an M dwarf binary system at 3.5 pc
No full textWe report the discovery of a super-Earth candidate orbiting the nearby mid-M dwarf Gl 725A using the radial velocity (RV) method. The planetary signal has been independently identified using high-precision RVs from the SOPHIE and SPIRou spectrographs, in the optical and near-infrared (NIR) domains, respectively. We modelled the stellar activity signal jointly with the planet using two Gaussian processes, one for each instrument to account for the chromaticity of the stellar activity and instrumental systematics, along with a Keplerian model. The signal was significantly detected with a RV semi-amplitude of 1.67 ± 0.20 m/s. The planet Gl725A b is found to be in an orbit compatible with circular with a period of 11.2201 ± 0.0051 days. We analysed 27 sectors of TESS photometry, for which no transit event was found. We determined a minimum mass of Mp sin i = 2.78 ± 0.35 M⊕, which places the planet in the super-Earth regime. Using mass-radius relationships, we predict the planetary radius to be between 1.2 and 2.0 R⊕. The proximity of Gl 725A (at only 3.5 pc) makes this new exoplanet one of the closest to Earth and joins the group of S-type low-mass planets in short orbits (P < 15 days) around close M dwarfs
A possible misaligned orbit for the young planet AU Mic c
No full textThe AU Microscopii planetary system is only 24 Myr old, and its geometry may provide clues about the early dynamicalhistory of planetary systems. Here, we present the first measurement of the Rossiter–McLaughlin effect for the warm sub-Neptune AU Mic c, using two transits observed simultaneously with the European Southern Observatory’s (ESO’s) VeryLarge Telescope (VLT)/Echelle SPectrograph for Rocky Exoplanets and Stable Spectroscopic Observations (ESPRESSO),CHaracterising ExOPlanet Satellite (CHEOPS), and Next-Generation Transit Survey (NGTS). After correcting for flares and forthe magnetic activity of the host star, and accounting for transit-timing variations, we find the sky-projected spin–orbit angle ofplanet c to be in the range λc = 67.8+31.7 −49.0 degrees (1σ). We examine the possibility that planet c is misaligned with respect to theorbit of the inner planet b (λb = −2.96+10.44 −10.30), and the equatorial plane of the host star, and discuss scenarios that could explainboth this and the planet’s high density, including secular interactions with other bodies in the system or a giant impact. We notethat a significantly misaligned orbit for planet c is in some degree of tension with the dynamical stability of the system, and withthe fact that we see both planets in transit, though these arguments alone do not preclude such an orbit. Further observationswould be highly desirable to constrain the spin–orbit angle of planet c more precisel
Impurity band formation as a route to thermoelectric power factor enhancement in n-type XNiSn half-Heuslers
No full textBandstructure engineering is a key route for thermoelectric performance enhancement. Here, 20–50% Seebeck (S) enhancement is reported for XNiCuySn half-Heusler samples based on X = Ti. This novel electronic effect is attributed to the emergence of impurity bands of finite extent, due to the Cu dopants. Depending on the dispersion, extent, and offset with respect to the parent material, these bands are shown to enhance S to different degrees. Experimentally, this effect is controllable by the Ti content of the samples, with the addition of Zr/Hf gradually removing the enhancement. At the same time, the mobility remains largely intact, enabling power factors ≥3 mW m−1 K−2 near room temperature, increasing to ≥5 mW m−1 K−2 at high temperature. Combined with reduced thermal conductivity due to the Cu interstitials, this enables high average zT = 0.67–0.72 between 320 and 793 K for XNiCuySn compositions with ≥70% Ti. This work reveals the existence of a new route for electronic performance enhancement in n-type XNiSn materials that are normally limited by their single carrier pocket. In principle, impurity bands can be applied to other materials and provide a new direction for further development
No right to an open future
No full textLiberals writing about the family frequently cite the child's ‘right to an open future’ in discussions of the ethics of parental decision-making for young children. This purported right grounds certain claims on behalf of children in considerations related to their future autonomy. In this article, I argue that there is no compelling argument in favor of a distinctive ‘right to an open future’ construed as either a negative or a positive right. Insofar as claims made about the content of this purported right are justified, they can be grounded in the interests of the child or in other uncontroversial rights. Talk of a ‘right to an open future’ serves only to obscure the ethical considerations that actually matter and citing the right is not helpful in deciding what may or should be done. I illustrate this claim by reference to two examples of how the ‘right to an open future’ has been applied: one regarding genetic testing for adult-onset disorders and one regarding selection for disabilities
An opinion regarding the grid layout as a goal and parameter
No full textThis opinion paper has the goal of offering two opinions as a guide for further and better research on the grid layout motivated by its coming back to planning research and practice. By analytical reasoning referencing relevant researches and real world examples, it gives from a town planner's perspective an account for both the popularity and resilience of the grid layout. The first opinion is that the grid layout (gridiron (orthogonal/rectangular)) is a default planning option in relation to the town and country layout or pattern of land apportionment. The second and more important, based on two case studies (one from colonial Hong Kong and another from the southern bank of the River Clyde, in Glasgow, Scotland), is that the conversion of an informal and customary layout into a formal grid land pattern and its subsequent modification is, in the word of Libecap et al. (2011), a major “institutional change” that involves high transaction costs measured in terms of time. Seven research issues are discussed.</p
