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Plasmon-induced transparency (PIT) metasurfaces have emerged as a promising platform for applications in ultrasensitive detection and slow-light devices. The active control of PIT metasurfaces is particularly crucial for advancing these applications. In this study, we integrate the phase change material Ge2Sb2Te5 (GST) into the structural design of a polarization-independent metasurface, enabling the experimental realization of ultra-large depth modulation of PIT peaks. This was achieved through direct thermal activation of the sample and laser-induced multilevel nonvolatile modulation, with a modulation range extending from 0% to 35.2%. The underlying mechanism for this significant modulation depth is attributed to the suppression of magnetic resonance by the GST phase transition, which is elucidated through analyses of multipolar scattering power, electric field distribution, and magnetic field distribution. The proposed terahertz metasurface presents a pathway for the development of optical switches and slow-light devices, with potential applications in advanced photonic systems. [ABSTRACT FROM AUTHOR]

Perfect vector vortex beams play a very important role in understanding complex structured beams due to their vortex nature and nonuniform polarization profiles. However, the generation of these beams suffers from a limited number of topological charges, bulky optical setup, lack of color information, and limited control along the light propagation direction. To tackle these fundamental and technical challenges, a metasurface approach to generating multiple grafted perfect vector vortex beams (GPVVBs) along the light propagation direction. GPVVBs with different colors are observed by changing the observation plane is proposed. Their polarization profiles are indirectly confirmed through the unique features in the modulated intensity profiles with an analyzer. Furthermore, the dynamic control of these beams is realized by continuously changing the incident polarization. Simultaneous control of color and topological charges in GPVVBs along the longitudinal direction provides more degrees of freedom for carrying information and has the potential to impact quantum science, singular optics, and optical communications. [ABSTRACT FROM AUTHOR]

Polarization state generation plays an important role in optics and are applied in many fields. Multispectral polarization manipulation can increase information capacity. To meet the requirement of miniaturization and integration, it is desirable to generate multispectral polarization states with a compact optical device. a metasurface device is proposed and experimentally demonstrated, which can simultaneously realize wavelength separation and polarization generation. A geometric metasurface is used to realize the phase and wavelength multiplexing. Six polarization states with different wavelengths are generated. Customized polarization states with predesigned wavelength information can add extra degrees of freedom for carrying information, opening a new window for portable polarization optics where low‐cost and miniaturized systems are in high demand. [ABSTRACT FROM AUTHOR]

Rationale: Among mechanically ventilated critically ill adults, the PILOT (Pragmatic Investigation of Optimal Oxygen Targets) trial demonstrated no difference in ventilator-free days among lower, intermediate, and higher oxygen-saturation targets. The effects on long-term cognition and related outcomes are unknown. Objectives: To compare the effects of lower (90% [range, 88–92%]), intermediate (94% [range, 92–96%]), and higher (98% [range, 96–100%]) oxygen-saturation targets on long-term outcomes. Methods: Twelve months after enrollment in the PILOT trial, blinded neuropsychological raters conducted assessments of cognition, disability, employment status, and quality of life. The primary outcome was global cognition as measured using the Telephone Montreal Cognitive Assessment. In a subset of patients, an expanded neuropsychological battery measured executive function, attention, immediate and delayed memory, verbal fluency, and abstraction. Measurements and Main Results: A total of 501 patients completed follow-up, including 142 in the lower, 186 in the intermediate, and 173 in the higher oxygen target groups. Median (interquartile range) peripheral oxygen saturation values in the lower, intermediate, and higher target groups were 94% (91–96%), 95% (93–97%), and 97% (95–99%), respectively. Telephone Montreal Cognitive Assessment score did not differ between lower and intermediate (adjusted odds ratio [OR], 1.36 [95% confidence interval (CI), 0.92–2.00]), intermediate and higher (adjusted OR, 0.90 [95% CI, 0.62–1.29]), or higher and lower (adjusted OR, 1.22 [95% CI, 0.83–1.79]) target groups. There was also no difference in individual cognitive domains, disability, employment, or quality of life. Conclusions: Among mechanically ventilated critically ill adults who completed follow-up at 12 months, oxygen-saturation targets were not associated with cognition or related outcomes. [ABSTRACT FROM AUTHOR]

As an attractive metal‐free conjugated polymer, graphitic carbon nitride (g‐C3N4) has attracted extensive attention in the field of solar energy conversion and storage as a visible light responsive hydrogen evolution. However, the photocatalytic efficiency of g‐C3N4 still has great room for improvement. Herein, a highly efficient visible‐light‐driven okra‐like tubular g‐C3N4photocatalyst (TCNMCA‐PImM) was synthesized via pyrolysis of a poly‐(imidazolium‐methylene) chloride (PImM)‐mediated molecular assembly prepared by a hydrothermal process of a solution containing PImM, melamine, and KOH, in which PImM acts as an electronic structure regulator owing to its strong hydrogen bond, π‐π interaction, and van der Waals force. On the basis of maintaining tri‐s‐triazine structure, the increase of graphitic N promotes the separation and transfer efficiency of photogenerated electrons and holes through the electron structure adjustment. The photocatalyst displays the notably promoted photocatalytic performance for H2 generation under visible‐light illumination. The optimized photocatalyst shows 1902 μmol h−1 g−1 of hydrogen evolution rate, which is 25.7 times higher than that of bulk g‐C3N4. The developed polymeric carbon nitride with unique geometric structure and electronic properties can be extended to other applications like CO2 capture for carbon neutralization strategy. [ABSTRACT FROM AUTHOR]

Active control of metamaterial properties in stretchable devices is crucial for advanced terahertz (THz) applications, involving large mechanical deformation or stretching. Single/double-layer mechanically tunable THz metamaterial devices based on the polymer polydimethylsiloxane are proposed and experimentally studied herein. The plasmon-induced transparency (PIT) effect is observed in the transmittance spectrum of the single-layer metamaterial, originating from the near-field coupling of two bright modes. Similarly, a bright-dark-coupled PIT system is obtained in the double-layer metamaterial. Furthermore, an external mechanical stretching could exert a switch effect on the sample. The PIT resonances of the single/double-layer metamaterials disappear when the stretching ratio is further increased, as the increased distance between the resonators blocks the coupling effect. The proposed design enriches the approaches to the modulation of the sensitive PIT effect and broadens the applications of stretchable THz equipment. [ABSTRACT FROM AUTHOR]

A polydimethylsiloxane (PDMS)-based stretchable metadevice for dual-band switching of terahertz radiation is experimentally demonstrated. The metasurface can efficiently excite dipole resonance of the metal structure and the surface Bloch mode generated by the periodic lattice substrate. In the tensile deformation operation, these two resonant modes show significant frequency shift sensitivity characteristics, which provides a feasible solution for the realization of dual-band terahertz switches. A transmittance modulation depth of 90% is achieved by the dipole resonance, with a frequency shift of 0.14 THz. The other transmittance modulation depth of 65% is achieved by the surface Bloch mode, with a frequency shift of 0.4 THz. The broad tuning of 0.4 THz is attributed to the surface mode is period-sensitive. This approach provides a promising method for broad frequency tuning of stretchable metasurfaces. [ABSTRACT FROM AUTHOR]

Full waveform inversion (FWI) plays a central role in the field of seismic processing due to the advantage in recovering the properties of the subsurface from seismograms. However, it suffers from more local minima convergence and more serious nonlinearity than the conventional seismic inversion method mainly caused by the lack of low-frequency information in the seismic data or the low-wavenumber components in the starting model. In this letter, we present a novel technique for seismic FWI based the angle difference identity for cosine, which builds an internal connection between high- and low-frequency signals. Thus, we can use the high-frequency information to get a plausible recovery of the low-wavenumber velocity. In addition, we choose the amplitude-independent objective function, which is given by maximizing the cross correlation between the modeled and observed data, to deal with the imperfect amplitude matching in the real case. Finally, a synthetic example of SEG/EAGE salt model is employed to demonstrate the validity of the proposed method, when low-frequency signals are absent. [ABSTRACT FROM AUTHOR]

Lithium–sulfur (Li–S) batteries have a distinct advantage over other rechargeable battery systems since their high specific energy and low cost. However, the diffusion of polysulfides from cathode to anode leads to poor electrochemical stability of Li–S batteries, which is a main factor that restricts their further development. Herein, for the first time we present a separator with nitrogen-doped porous hollow carbon sphere (NHC) coating, with which Li–S cells enormously improve the utilization of active material and enhance excellent electrochemical performance. An initial discharge capacity of 1656 mAh g −1 (0.2 C) and a low fading rate of 0.11% per cycle within 500 cycles (1 C) are achieved, which ascribe to the chemical and physical adsorption properties of porous and nitrogen-doped NHCs. The NHC-decorated separator is of low cost and can effectively improve energy density of Li–S cells, exhibiting potential for further development of Li–S batteries. [ABSTRACT FROM AUTHOR]

The rate performance of LiFePO4 batteries is improved by inserting a carbon interlayer, which is synthesized by a simple and cheap pyrolysis of the filter paper commonly used in the laboratories. The specific capacity of the LiFePO4 batteries at low current density is only slightly improved after the introduction of the carbon interlayer, while the specific capacity at high current density is greatly enhanced with a specific capacity of 90 mA h g−1 and 76 mA h g−1 at 10 C and 20 C, respectively, compared to a specific capacity of 17 mA h g−1 and 8 mA h g−1 of LiFePO4 batteries without a carbon interlayer. The improved electrochemical performance is attributed to the porous architecture of the carbon interlayer, serving as a conductive skeleton, largely reducing the charge transfer resistance. [ABSTRACT FROM AUTHOR]

As one of the most promising high-energy lithium batteries, the commercialization of lithium–sulfur (Li–S) batteries remains a huge challenge due to their poor rate performance and low cycle stability, which originate partly from the dissolution of polysulfides and their migration from the S cathode to the Li anode through the separator. Novel sulfur-based composite cathodes have been constantly put forward to restraint the dissolution of polysulfides; however, less attention has been paid to modifying the separator. In this work, a multi-walled carbon nanotube@polyethylene glycol (MCNT@PEG) composite is designed and prepared to modify the commercial Celgard separator. With the bifunctional MCNT@PEG-modified separator, Li–S cells possess a high initial discharge capacity of 1283 mA h g−1 at 0.5 C and undertake a long charge/discharge process of 500 cycles at 1 C with 0.12% capacity fading per cycle. Moreover, when the rate is increased to 5 C, the cells can also deliver a discharge capacity of 657 mA h g−1. These encouraging electrochemical results highlight the excellent rate capability and high cycle stability of Li–S cells, which could be attributed to the strong chemical and physical absorption properties and high electron conductivity of the MCNT@PEG layer. This facile approach to restrain the shuttle effect of polysulfides makes further progress in obtaining the enhanced performance of Li–S batteries. [ABSTRACT FROM AUTHOR]

Multi-walled carbon nanotube/selenium composites (MWCNT/Se) are prepared via a simple solution-based processing strategy using ethylenediamine as the solvent. The selenium nanoparticles in diameter of about 100 nm are homogeneously deposited on the network of multi-walled carbon nanotubes in the composites. Compared with multi-walled carbon nanotube/selenium composites by melt-infusing method (MWCNT/Se-M), the multi-walled carbon nanotube/selenium composites by solution-based process (MWCNT/Se–S) can deliver a much higher initial discharge capacity (645.7 mAh g −1 ) and a better cycling stability (355.5 mAh g −1 remaining at a rate of 0.5C after 100 cycles). Even at 4C, it still exhibits a reversible capacity of 468.7 mAh g −1 . The superior electrochemical properties of multi-walled carbon nanotube/selenium composites via solution-based process could be ascribed to the diminished size of selenium and uniform distribution of selenium nanoparticles in carbon matrix. [ABSTRACT FROM AUTHOR]

Tunable metasurfaces offer a promising avenue for dynamically modulating terahertz waves. Phase-change materials are crucial in this dynamic modulation, enabling precise and reversible control over the electromagnetic properties of the metasurfaces. In this study, we designed and experimentally fabricated a tunable lattice-induced transparent metasurface. This metasurface comprises two gold rod resonators exhibiting different periodic distributions, each supporting an electric dipole resonance at 2.03 THz and a surface lattice resonance at 1.51 THz, respectively. By combining these structures, we realize lattice-induced transparency. Simulation results show that the phase change of Ge 2 Sb 2 Te 5 modulates these resonances, with the crystalline state significantly weakening their resonance strength intensity. The maximum modulation depth of the lattice-induced transparency peak can reach 44.4%. Experimental results of laser-induced GST phase changes confirm a modulation depth of 42.4%. This innovative metasurface design holds promise for applications in terahertz communication systems.

Although both short and long sleep duration are associated with elevated hypertension risk, our understanding of their interplay with biological pathways governing blood pressure remains limited. To address this, we carried out genome-wide cross-population gene-by-short-sleep and long-sleep duration interaction analyses for three blood pressure traits (systolic, diastolic, and pulse pressure) in 811,405 individuals from diverse population groups. We discover 22 novel gene-sleep duration interaction loci for blood pressure, mapped to 23 genes. Investigating these genes' functional implications shed light on neurological, thyroidal, bone metabolism, and hematopoietic pathways that necessitate future investigation for blood pressure management that caters to sleep health lifestyle. Non-overlap between short sleep (12) and long sleep (10) interactions underscores the plausible nature of distinct influences of both sleep duration extremes in cardiovascular health. Several of our loci are specific towards a particular population background or sex, emphasizing the importance of addressing heterogeneity entangled in gene-environment interactions, when considering precision medicine design approaches for blood pressure management., Competing Interests: Declarations CONFLICT OF INTEREST C.L.M. has received funding from AstraZeneca not related to the current study. B.M.P. serves on the steering committee of the Yale Open Data Access Project funded by Johnson & Johnson. D.C. receives consultancy fees from Roche Diagnostics and Trimedics and speaker fees from Servier. D.A.L. has received support from Medtronic LTD and Roche Diagnostics for biomarker research not related to the current study. The remaining authors declare no competing interests.

Oxygen-excess La 2 NiO 4+ δ (LNO) conducts oxide ions, electron holes, and hydroxide ions simultaneously on exposing to wet oxygen, exhibiting the potential as a cathode material in protonic ceramic fuel cells. Since the incorporation of protons in oxygen-excess LNO is via the hydration reaction assisted by interstitial oxide ions, in this work, the concentration of interstitial oxide ions is reduced and increased by substituting Ni with Cu and Co, respectively. A higher concentration of interstitial oxide ions leads to a high proton concentration, indicating the predominant role of interstitial oxide ions in the hydration reaction, different from that in the oxygen-deficient oxides, where protons are introduced by dissociative absorption of water molecules by oxygen vacancies. The theoretical calculation indicates that protons in Co-doped LNO prefer to locate between the interstitial oxide ions and unshared apical oxide ions. A trapping effect is found between protons and the oxide ions near Cu, leading to decreased proton mobility. Protonic conductivity at 400-575 °C is then directly measured by a Hebb-Wagner direct current polarization method with La 0.99 Ca 0.01 NbO 4- δ as the blocking electrode, enabling the observation that Co-doped LNO has the highest protonic conductivity among the samples studied in this work., (© 2024 Wiley‐VCH GmbH.)

Although both short and long sleep duration are associated with elevated hypertension risk, our understanding of their interplay with biological pathways governing blood pressure remains limited. To address this, we carried out genome-wide cross-population gene-by-short-sleep and long-sleep duration interaction analyses for three blood pressure traits (systolic, diastolic, and pulse pressure) in 811,405 individuals from diverse population groups. We discover 22 novel gene-sleep duration interaction loci for blood pressure, mapped to genes involved in neurological, thyroidal, bone metabolism, and hematopoietic pathways. Non-overlap between short sleep (12) and long sleep (10) interactions underscores the plausibility of distinct influences of both sleep duration extremes in cardiovascular health. With several of our loci reflecting specificity towards population background or sex, our discovery sheds light on the importance of embracing granularity when addressing heterogeneity entangled in gene-environment interactions, and in therapeutic design approaches for blood pressure management., Competing Interests: Conflict of Interest/Disclosures: C.L.M. has received funding from AstraZeneca not related to the current study. B.M.P. serves on the steering committee of the Yale Open Data Access Project funded by Johnson & Johnson. D.C. receives consultancy fees from Roche Diagnostics and Trimedics and speaker fees from Servier. D.A.L. has received support from Medtronic LTD and Roche Diagnostics for biomarker research not related to the current study. The remaining authors declare no competing interests.

Generation and manipulation of three-dimensional (3D) optical polarization structures have received considerable interest because of their distinctive optical features and potential applications. However, the realization of multiple 3D polarization structures in a queue along the light propagation direction has not yet been reported. We propose and experimentally demonstrate a metalens to create longitudinally variable 3D polarization knots. A single metalens can simultaneously generate three distinct 3D polarization knots, which are indirectly validated with a rotating polarizer. The 3D polarization profiles are dynamically modulated by manipulating the linear polarization direction of the incident light. We further showcase the 3D image steganography with the generated 3D polarization structures. The ultrathin nature of metasurfaces and unique properties of the developed metalenses hold promise for lightweight polarization systems applicable to areas such as 3D image steganography and virtual reality.

Frequency-induced instability is widely present in nematic liquid crystals (LCs), which poses a problem in improving liquid-crystal-based phase-shift devices driven by alternating currents. Herein, the Fréedericksz transition of thick nematic LCs was investigated under alternating electric fields to reveal the suppression of frequency-induced instability in the low frequency range. By extending the Frank-Leslie equation to the AC-driven case, the response of the LC was numerically calculated, and the frequency threshold for suppressing the driven instability was estimated in conjunction with the perturbation method. Experimentally, the frequency suppression of LC fluctuations was verified by using applied electric fields. In addition, the root-mean-square-error of the refractive index was measured to be less than 2 × 10 -5 , which excludes the convective instability-generating domains in devices. It was revealed that the fabricated thick LC phase shifters provided a phase shift of more than 360° at 2 THz and can be used in the terahertz band. It was observed that the electrically driven phase-shift characteristics were in accordance with the theoretical results as the threshold frequency condition was satisfied. This work provides an experimental and theoretical reference for improving modulation performance and enhancing the characterization of AC-driven LC-based phase-shift devices.

To develop a non-precious highly efficient cocatalyst to replace Pt on graphitic carbon nitride (g-C 3 N 4 ) for solar H 2 production is great significant, but still remains a huge challenge. The emerging single-atom catalyst presents a promising strategy for developing highly efficient non-precious cocatalyst owing to its unique adjustability of local coordination environment and electronic structure. Herein, this work presents a facile approach to achieve single Ni sites (Ni 1 -N 2 S) with unique local coordination structure featuring one Ni atom coordinated with two nitrogen atoms and one sulfur atom, confirmed by high-angle annular dark-field scanning transmission electron microscopy, X-ray absorption spectroscopy, and density functional theory calculation. Thanks to the unique electron structure of Ni 1 -N 2 S sites, the 1095 µmol g -1 h -1 of high H 2 evolution rate with 4.1% of apparent quantum yield at 420 nm are achieved. This work paves a pathway for designing a highly efficient non-precious transition metal cocatalyst for photocatalytic H 2 evolution., (© 2022 Wiley-VCH GmbH.)

Manipulating the polarization state of terahertz waves is critical for terahertz communication systems. This study proposes a terahertz band polarization conversion metasurface based on dislocation-induced anisotropy. Numerical simulation results revealed that the polarization conversion of orthogonal linearly polarized light, orthogonal circularly polarized light, linearly polarized light to circularly polarized light, and circularly polarized light to linearly polarized light can be realized. Furthermore, the simulation revealed that multifunctional polarization conversion could be achieved by various structures of the bilayer metasurface. Thus, the proposed design can be generalized. The proposed metasurface exhibits considerable potential for applications in terahertz communications.