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Background: The type II based CRISPR-Cas system remains restrictedly utilized in archaea, a featured domain of life that ranks parallelly with Bacteria and Eukaryotes. Methanococcus maripaludis, known for rapid growth and genetic tractability, serves as an exemplary model for studying archaeal biology and exploring CO2−based biotechnological applications. However, tools for controlled gene regulation remain deficient and CRISPR-Cas tools still need improved in this archaeon, limiting its application as an archaeal model cellular factory. Results: This study not only improved the CRISPR-Cas9 system for optimizing multiplex genome editing and CRISPR plasmid construction efficiencies but also pioneered an effective CRISPR interference (CRISPRi) system for controlled gene regulation in M. maripaludis. We developed two novel strategies for balanced expression of multiple sgRNAs, facilitating efficient multiplex genome editing. We also engineered a strain expressing Cas9 genomically, which simplified the CRISPR plasmid construction and facilitated more efficient genome modifications, including markerless and scarless gene knock-in. Importantly, we established a CRISPRi system using catalytic inactive dCas9, achieving up to 100-fold repression on target gene. Here, sgRNAs targeting near and downstream regions of the transcription start site and the 5′end ORF achieved the highest repression efficacy. Furthermore, we developed an inducible CRISPRi-dCas9 system based on TetR/tetO platform. This facilitated the inducible gene repression, especially for essential genes. Conclusions: Therefore, these advancements not only expand the toolkit for genetic manipulation but also bridge methodological gaps for controlled gene regulation, especially for essential genes, in M. maripaludis. The robust toolkit developed here paves the way for applying M. maripaludis as a vital model archaeal cell factory, facilitating fundamental biological studies and applied biotechnology development of archaea. [ABSTRACT FROM AUTHOR]

Sodium-ion batteries (SIBs) are suitable candidates in energy storage due to their abundant source and competitive performance. Despite their proven effectiveness and competitiveness, layered oxide cathodes for SIBs encounter challenges related to structural integrity over cycles. This study explores the incorporation of strontium (Sr), a rarely utilized element with a large radius, in P2-type layered oxides as a solution. The research uncovers unique crystal structural changes induced by Sr2+, resulting in suppressed phase transitions and enhanced stability. Through a combination of characterization techniques, novel alterations in crystal parameters are observed, addressing the limitations of traditional nickel/manganese-based oxides. Ex situ X-ray photoelectron spectroscopy (XPS) confirms the suppressed Jahn–Teller effect, indicating improved stability. Additionally, density functional theory (DFT) calculations suggest a dual role for Sr2+ ions as "pillars" and "cords" within sodium layers, promoting sodium diffusion. Experimental results demonstrate increased retention and specific capacity with Sr2+ doping, even at high current rates, showcasing its potential for commercialization. This research sheds light on the impact of large-radius ion doping, offering a significant advancement in stable SIB cathode materials development. [ABSTRACT FROM AUTHOR]

Tunable electromagnetic (EM) metamaterials have received significant attention due to their compelling advantages of integration and minimization compared with conventional bulky devices. Meanwhile, mechanically reconfigurable metamaterials have witnessed a striving period over recent years due to their simplified structural composition and confined modulation capabilities. Here, a controllable‐wrinkling‐based reconfiguration method is proposed to design split‐ring resonant units with dynamic transmittance spectra by switching between planar and wrinkling morphologies. For the linear polarized incidence, the geometries of planar and wrinkled units are optimized to achieve on‐demanded manipulation of the phases and amplitudes, respectively. By simultaneously implementing the amplitude design and the phase gradient, the mechanically inspired metamaterial is engineered to display a near‐field and a holographic image. For circularly polarized incidences, the spin‐decoupled phases and chiral effects demonstrated in the planar and wrinkled state assist in designing a metamaterial to possess spin‐multiplexed and strain‐modulated fourfold displays. These results demonstrate the practical feasibility of the wrinkling method in engineering tunable metamaterials, and the design flexibility, as well as the mechanical strategy, can extend the potential toward the application scenarios such as information processing, sensing, imaging, flexible meta‐devices, etc. [ABSTRACT FROM AUTHOR]

Donor-acceptor semiconducting polymers present countless opportunities for application in photocatalysis. Previous studies have showcased their advantages through direct bottom-up methods. Unfortunately, these approaches often involve harsh reaction conditions, overlooking the impact of uncontrolled polymerization degrees on photocatalysis. Besides, the mechanism behind the separation of electron-hole pairs (excitons) in donor-acceptor polymers remains elusive. This study presents a post-synthetic method involving the light-induced transformation of the building blocks of hyper-cross-linked polymers from donor-carbon-donor to donor-carbon-acceptor states, resulting in a polymer with a substantial intramolecular dipole moment. Thus, excitons are efficiently separated in the transformed polymer. The utility of this strategy is exemplified by the enhanced photocatalytic hydrogen peroxide synthesis. Encouragingly, our observations reveal the formation of intramolecular charge transfer states using time-resolved techniques, confirming transient exciton behavior involving separation and relaxation. This light-induced method not only guides the development of highly efficient donor-acceptor polymer photocatalysts but also applies to various fields, including organic solar cells, light-emitting diodes, and sensors. Donor-acceptor polymers have potential for application in photocatalysis, but often harsh synthetic conditions are required. Here, the authors report a post-synthetic method for conversion to donor-acceptor states, to give a polymer capable of enhancing photocatalytic hydrogen peroxide synthesis. [ABSTRACT FROM AUTHOR]

Tunable metamaterials offer versatile approaches to achieve the dynamic manipulation of electromagnetic waves with various dimensionality. Recently, mechanical approaches have been extensively employed to construct reconfigurable metamaterials with simple composition and superior mechanical characteristics. Mechanical modulation methods in phase‐gradient metamaterials are even more worthy of being investigated to facilitate valuable applications. Here, an in‐plane rotational deformation principle is proposed to assist the structural design of reconfigurable phase‐gradient metamaterials by integrating split ring resonators (SRRs) on the hyperelastic kirigami substrate. The orientations and split angles of SRRs are explored to manipulate the amplitudes and phases of cross‐polarized transmittance under x‐polarized incidence, respectively. The tensile strains dramatically modulate the amplitudes yet not the gradient phase. As proof‐of‐concept, a reconfigurable metalens is elaborately designed to realize tunable focus location and number by regulating the transmittance amplitudes of meta‐atoms via stretching the kirigami substrate. Furthermore, a holographic metamaterial is developed to perform dynamic hologram on the imaging plane under the strain 0% and 40%. The proposed mechanical deformation principle offers a promising platform for dynamic manipulation of the wavefront and may promote the conformal and flexible designs in certain cases and enlarge the potential applications of meta‐devices in imaging and information encryption. [ABSTRACT FROM AUTHOR]

NiMn2O4/C hollow spheres with sandwich-structured shells were fabricated by a hydrothermal method. Leveraging the mesoporous design of the carbon hollow spheres, NiMn2O4 nanosheets were evenly dispersed on both the inner and outer surfaces of the carbon shells. NiMn2O4/C demonstrated excellent rate capability and prolonged cycling durability for sodium ion storage. [ABSTRACT FROM AUTHOR]

Cooperative coupling of H2 evolution with oxidative organic synthesis is promising in avoiding the use of sacrificial agents and producing hydrogen energy with value‐added chemicals simultaneously. Nonetheless, the photocatalytic activity is obstructed by sluggish electron‐hole separation and limited redox potentials. Herein, Ni‐doped Zn0.2Cd0.8S quantum dots are chosen after screening by DFT simulation to couple with TiO2 microspheres, forming a step‐scheme heterojunction. The Ni‐doped configuration tunes the highly active S site for augmented H2 evolution, and the interfacial Ni−O bonds provide fast channels at the atomic level to lower the energy barrier for charge transfer. Also, DFT calculations reveal an enhanced built‐in electric field in the heterojunction for superior charge migration and separation. Kinetic analysis by femtosecond transient absorption spectra demonstrates that expedited charge migration with electrons first transfer to Ni2+ and then to S sites. Therefore, the designed catalyst delivers drastically elevated H2 yield (4.55 mmol g−1 h−1) and N‐benzylidenebenzylamine production rate (3.35 mmol g−1 h−1). This work provides atomic‐scale insights into the coordinated modulation of active sites and built‐in electric fields in step‐scheme heterojunction for ameliorative photocatalytic performance. [ABSTRACT FROM AUTHOR]

Cooperative coupling of H2 evolution with oxidative organic synthesis is promising in avoiding the use of sacrificial agents and producing hydrogen energy with value‐added chemicals simultaneously. Nonetheless, the photocatalytic activity is obstructed by sluggish electron‐hole separation and limited redox potentials. Herein, Ni‐doped Zn0.2Cd0.8S quantum dots are chosen after screening by DFT simulation to couple with TiO2 microspheres, forming a step‐scheme heterojunction. The Ni‐doped configuration tunes the highly active S site for augmented H2 evolution, and the interfacial Ni−O bonds provide fast channels at the atomic level to lower the energy barrier for charge transfer. Also, DFT calculations reveal an enhanced built‐in electric field in the heterojunction for superior charge migration and separation. Kinetic analysis by femtosecond transient absorption spectra demonstrates that expedited charge migration with electrons first transfer to Ni2+ and then to S sites. Therefore, the designed catalyst delivers drastically elevated H2 yield (4.55 mmol g−1 h−1) and N‐benzylidenebenzylamine production rate (3.35 mmol g−1 h−1). This work provides atomic‐scale insights into the coordinated modulation of active sites and built‐in electric fields in step‐scheme heterojunction for ameliorative photocatalytic performance. [ABSTRACT FROM AUTHOR]

Terahertz metamaterials have received significant attention for their unprecedented abilities to modulate the terahertz wave effectively. The traditional manufacturing of terahertz metamaterials has been mainly relying on the micro–nanofabrication technique due to the micro-scale characteristic size of the unit cell. However, the fabrication usually involves multi-step and time-consuming processes, as well as expensive equipment. To overcome these shortcomings, here we used projection micro-stereolithography 3D printing followed by the magnetron sputtering to additively manufacture terahertz metamaterials. A vertical split-ring resonator-based metamaterial absorber is taken into account as the prototype to demonstrate the simplicity of the proposed fabrication technique. Both terahertz time-domain spectroscopy measurement and simulation indicate that the 3D printed absorber has a near-unity narrow-band absorption peak at 0.8 THz. The absorption mechanism is clearly clarified by the coupled mode and impedance matching theory and electromagnetic field distribution at the resonant frequency. A 3D printed narrow-band absorber also demonstrates great potential for highly efficient biosensing of lactose and galactose. It can be estimated that 3D printing provides an easy-going fabrication approach for THz metamaterials and shed light on its foreseeable application for the versatile design and manufacturing of functional THz devices. [ABSTRACT FROM AUTHOR]

Metamaterials for electromagnetically induced transparency (EIT) have promoted prosperous development of terahertz (THz) devices due to their counterintuitive manipulation rules on the electromagnetic responses. However, traditional design rules of EIT metamaterial require prior knowledge of unnatural parameters of geometrical structures. Here, by taking full advantages of unsupervised generative adversarial networks (GANs), we propose an adaptively reverse design strategy to achieve intelligent design of metamaterial structures with the EIT phenomenon. The game theory ingrained in the GAN model facilitates the effective and error-resistant design process of metamaterial structures with preset electromagnetic responses and vice versa. The close match between the preset electromagnetic response and that from the generated structure validates the feasibility of the GAN model. Thanks to high efficiency and complete independence from prior knowledge, our method could provide a novel design technique for metamaterials with specific functions and shed light on their powerful capabilities on boosting the development of THz functional devices. [ABSTRACT FROM AUTHOR]

In the era of the digital economy, building an internationally competitive manufacturing industry with intelligent manufacturing as its main focus is the only way to promote the transformation of a country into a manufacturing power and achieve high-quality economic development. To explore whether Digital transformation can improve the core competitiveness of traditional manufacturing enterprises, and what factors affect this process, this study establishes the core competitiveness system of enterprises through the principal component analysis(PCA) method and discusses the above issues through the construction of a double difference model. The results of this research from China's traditional manufacturing industry are as follows. (i) The digital transformation of enterprises has significantly improved their core competitiveness and has a certain time lag effect. (ii) In the process of enterprise digital transformation, enterprise management capabilities, environmental uncertainty, and enterprise operational efficiency will positively enhance the results of enterprise digital transformation. (iii) The enhancement of core competitiveness caused by digital transformation is more significant for the market leaders and laggards. (iv) Compared with non-state-owned enterprises, the Digital Transformationn of state-owned enterprises has a more obvious effect on promoting their core competitiveness. (v) In comparison with enterprises with low government subsidies, the Digital Transformation of enterprises with high government subsidies plays a more significant role in promoting their core competitiveness. In addition, this study proposes policy guidance and practical guidance for digital transformation to accelerate the promotion of core competitiveness of traditional manufacturing industry. [ABSTRACT FROM AUTHOR]

The present study reports on a computational model that systematically evaluates the effect of physical factors, including size, surface modification, and rigidity, on the nuclear uptake of nanoparticles (NPs). The NP–nucleus interaction is a crucial factor in biomedical applications such as drug delivery and cellular imaging. While experimental studies have provided evidence for the influence of size, shape, and surface modification on nuclear uptake, theoretical investigations on how these physical factors affect the entrance of NPs through the nuclear pore are lacking. Our results demonstrate that larger NPs require a higher amount of energy to enter the nucleus compared to smaller NPs. This highlights the importance of size as a critical factor in NP design for nuclear uptake. Additionally, surface modification of NPs can impact the nuclear uptake pathway, indicating the potential for tailored NP design for specific applications. Notably, our findings also reveal that the rigidity of NPs has a significant effect on the transport process. The interplay between physicochemical properties and nuclear pore is found to determine nuclear uptake efficiency. Taken together, our study provides new insights into the design of NPs for precise and controllable NP–nucleus interaction, with potential implications for the development of efficient and targeted drug delivery systems and imaging agents. [ABSTRACT FROM AUTHOR]

The Kirigami technique has recently inspired the design of reconfigurable electromagnetic metamaterials that can be easily realized by embedding a patterned cutting array into a supportive substrate. However, these existing designs mainly focus on the 2D‐to‐3D transformable morphology that induces the modulation of the spectral responses. This work proposes a kirigami‐based planar reconfiguration mechanism and extends advanced applications in the dynamic near‐field imaging and tunable double‐foci metalens. These extraordinary tunabilities originate from three meta‐atoms that can be mutually transformed into the morphologies with non‐chirality and opposite chirality under the tensile strain. By utilizing the transmittance characteristics of reconfigurable meta‐atoms, the metamaterial is constructed to achieve three‐foldable near‐field displays and a longitudinal double‐foci metalens empowered with tunable focusing length and intensity ratio. Two anisotropic chiral meta‐atoms in deformed states that possess overwhelming transmittance difference of circularly cross‐polarized components to magnify the focusing intensity ratio of two foci for the proposed metalens are further proposed. The exhibited observations provide typical examples of a wide spectrum of applications of the kirigami‐based reconfiguration mechanism, and it may pave the avenue to spark manifold functional devices for applicable electromagnetic manipulations such as multifunctional hologram display, dynamic beam shaping, and steering, as well as the conformal design of meta‐devices. [ABSTRACT FROM AUTHOR]

Hyperbolic metamaterial, a novel type of anisotropic bulk material, can enhance the near-field radiation heat transfer (NFRHT) via supporting unbounded hyperbolic phonon polaritons (HPPs). A cutting-edge two-dimensional material, black phosphorous (BP), also gives a rise to promising performance in the NFRHT due to its excitation of surface plasmon polaritons (SPPs). Here, by coupling SPPs with HPPs, we have proposed a hybrid heterostructure that consists of a single top-covered BP layer with doped-Si nanowire arrays (D-SiNWs) and explored the NFRHT between two heterostructures separated by a vacuum gap. The hybrid heterostructure enables a significant enhancement of NFRHT contributed to the excited hybridized modes of BP plasmons and HPPs. The SPPs of BP expand the effective range of HPPs to the high-k space, resulting in a heat transfer coefficient that is 2.9 times and 1.7 times larger than that of two D-SiNWs and two monolayer BPs, respectively. Influences of electron density of BP are conclusively clarified from the profile of the plasma dispersion relation. Thus, it is expected that the proposed configuration can be used to regulate the near-field heat transfer in a tunable fashion and shed light on an invaluable technique toward the design of two-dimensional materials for thermal and electrical applications. [ABSTRACT FROM AUTHOR]

The electromagnetically induced transparency (EIT) metamaterials with active or passive modulation have been extensively studied and applied in slow-light devices, light on-off, and light storage. However, the preparation complexity and characterization difficulties of the EIT metamaterials limit their optoelectronic applications. Here, we have employed a structure-based tunable design to fulfill the passive modulation of EIT metamaterial. We propose a simple but effective EIT structural model composed of a cutting wire and two circular split rings. Through theoretical analysis and computational simulation, it is found that the localized surface plasma and the inductive-capacitive resonance mode coincidently contribute to the EIT effect, giving rise to a narrow transparency window. Moreover, the amplitude of the transparency peak gradually decreases at the same resonance frequency with the increment of the lateral distance between the wire and split ring, while it decreases proportionally with the increment of the radius of the split ring. Interestingly, when the radius continues to increase, the asymmetry of the EIT window aggravates and the second EIT broad transparency window appears, indicating the existence of another intriguing coupling mechanism. Our work unveils a simple and practical modulation strategy for EIT-based multifunctional optical devices and shed light on its potential application on the optical devices. [ABSTRACT FROM AUTHOR]

Zhang (2021), Luo and Yin (2022) initiated the study of Lagrangian submanifolds satisfying ∇*T = 0 or ∇*∇*T = 0 in ℂn or ℂℙn, where T = ∇ ∗ h ˜ and h ˜ is the Lagrangian trace-free second fundamental form. They proved several rigidity theorems for Lagrangian surfaces satisfying ∇*T = 0 or ∇*∇*T = 0 in ℂ2 under proper small energy assumption and gave new characterization of the Whitney spheres in ℂ2. In this paper, the authors extend these results to Lagrangian submanifolds in ℂn of dimension n ≥ 3 and to Lagrangian submanifolds in ℂℙn. [ABSTRACT FROM AUTHOR]

The interaction between a co‐catalyst and photocatalyst usually induces spontaneous free‐electron transfer between them, but the effect and regulation of the transfer direction on the hydrogen‐adsorption energy of the active sites have not received attention. Herein, to steer the free‐electron transfer in a favorable direction for weakening S−Hads bonds of sulfur‐rich MoS2+x, an electron‐reversal strategy is proposed for the first time. The core–shell Au@MoS2+x cocatalyst was constructed on TiO2 to optimize the antibonding‐orbital occupancy. Research results reveal that the embedded Au can reverse the electron transfer to MoS2+x to generate electron‐rich S(2+δ)− active sites, thus increasing the antibonding‐orbital occupancy of S−Hads in the Au@MoS2+x cocatalyst. Consequently, the increase in the antibonding‐orbital occupancy effectively destabilizes the H 1s‐p antibonding orbital and weakens the S−Hads bond, realizing the expedited desorption of Hads to rapidly generate a lot of visible H2 bubbles. This work delves deep into the latent effect of the photocatalyst carrier on cocatalytic activity. [ABSTRACT FROM AUTHOR]

The interaction between a co‐catalyst and photocatalyst usually induces spontaneous free‐electron transfer between them, but the effect and regulation of the transfer direction on the hydrogen‐adsorption energy of the active sites have not received attention. Herein, to steer the free‐electron transfer in a favorable direction for weakening S−Hads bonds of sulfur‐rich MoS2+x, an electron‐reversal strategy is proposed for the first time. The core–shell Au@MoS2+x cocatalyst was constructed on TiO2 to optimize the antibonding‐orbital occupancy. Research results reveal that the embedded Au can reverse the electron transfer to MoS2+x to generate electron‐rich S(2+δ)− active sites, thus increasing the antibonding‐orbital occupancy of S−Hads in the Au@MoS2+x cocatalyst. Consequently, the increase in the antibonding‐orbital occupancy effectively destabilizes the H 1s‐p antibonding orbital and weakens the S−Hads bond, realizing the expedited desorption of Hads to rapidly generate a lot of visible H2 bubbles. This work delves deep into the latent effect of the photocatalyst carrier on cocatalytic activity. [ABSTRACT FROM AUTHOR]

Due to the absence of a comprehensive knowledge system for modeling ocean circulation, there is ambiguity and diversity in the semantic expression of ocean circulation. This makes it difficult to organize and share relevant spatiotemporal data effectively. This paper addresses the issue of ocean circulation by introducing ontological theory and methodology based on a comprehensive analysis of domain knowledge. Through a comprehensive analysis of the conceptual and relational characteristics of different elements, we define classes, properties, spatiotemporal relationships, and inference conditions with which to formally express concepts and relationships in ocean circulation, and finally complete the construction of ocean circulation ontology. The formal expression of the Equatorial Counter Current is presented as an example with which to validate the effectiveness of ontological construction. Additionally, an ontology-based knowledge base of ocean circulation is proposed. The construction framework is described, and several examples of knowledge base queries are also illustrated. The results demonstrate that this ontology can effectively represent the relevant knowledge within ocean circulation and provide a meaningful reference for investigating knowledge sharing and semantic integration within this field. [ABSTRACT FROM AUTHOR]

The S‐scheme heterojunction is flourishing in photocatalysis because it concurrently realizes separated charge carriers and sufficient redox ability. Steady‐state charge transfer has been confirmed by other methods. However, an essential part, the transfer dynamics in S‐scheme heterojunctions, is still missing. To compensate, a series of cadmium sulfide/pyrene‐alt‐difluorinated benzothiadiazole heterojunctions were constructed and the photophysical processes were investigated with femtosecond transient absorption spectroscopy. Encouragingly, an interfacial charge‐transfer signal was detected in the spectra of the heterojunction, which provides solid evidence for S‐scheme charge transfer to complement the results from well‐established methods. Furthermore, the lifetime for interfacial charge transfer was calculated to be ca. 78.6 ps. Moreover, the S‐scheme heterojunction photocatalysts exhibit higher photocatalytic conversion of 1,2‐diols and H2 production rates than bare cadmium sulfide. [ABSTRACT FROM AUTHOR]

The S‐scheme heterojunction is flourishing in photocatalysis because it concurrently realizes separated charge carriers and sufficient redox ability. Steady‐state charge transfer has been confirmed by other methods. However, an essential part, the transfer dynamics in S‐scheme heterojunctions, is still missing. To compensate, a series of cadmium sulfide/pyrene‐alt‐difluorinated benzothiadiazole heterojunctions were constructed and the photophysical processes were investigated with femtosecond transient absorption spectroscopy. Encouragingly, an interfacial charge‐transfer signal was detected in the spectra of the heterojunction, which provides solid evidence for S‐scheme charge transfer to complement the results from well‐established methods. Furthermore, the lifetime for interfacial charge transfer was calculated to be ca. 78.6 ps. Moreover, the S‐scheme heterojunction photocatalysts exhibit higher photocatalytic conversion of 1,2‐diols and H2 production rates than bare cadmium sulfide. [ABSTRACT FROM AUTHOR]

Femtosecond transient absorption spectroscopy (fs-TAS) is a powerful technique for monitoring the electron transfer kinetics in photocatalysis. Several important works have successfully elucidated the electron transfer mechanism in heterojunction photocatalysts (HPs) using fs-TAS measurements, and thus a timely summary of recent advances is essential. This feature article starts with a thorough interpretation of the operating principle of fs-TAS equipment, and the fundamentals of the fs-TAS spectra. Subsequently, the applications of fs-TAS in analyzing the dynamics of photogenerated carriers in semiconductor/metal HPs, semiconductor/carbon HPs, semiconductor/semiconductor HPs, and multicomponent HPs are discussed in sequence. Finally, the significance of fs-TAS in revealing the ultrafast interfacial electron transfer process in HPs is summarized, and further research on the applications of fs-TAS in photocatalysis is proposed. This feature article will provide deep insight into the mechanism of the enhanced photocatalytic performance of HPs from the perspective of electron transfer kinetics. [ABSTRACT FROM AUTHOR]

Hemicellulose is the second most abundant natural polysaccharide and a promising feedstock for biomaterial synthesis. In the present study, the hemicellulose of loblolly pine was obtained by the alkali extraction-graded ethanol precipitation technique, and the hemicellulose-polyvinyl alcohol (hemicellulose-PVA) composite film was prepared by film casting from water. Results showed that hemicellulose with a low degree of substitution is prone to self-aggregation during film formation, while hemicellulose with high branching has better compatibility with PVA and is easier to form a homogeneous composite film. In addition, the higher molecular weight of hemicellulose facilitates the preparation of hemicellulose-PVA composite film with better mechanical properties. More residual lignin in hemicellulose results in the better UV shielding ability of the composite film. This study provides essential support for the efficient and rational utilization of hemicellulose. [ABSTRACT FROM AUTHOR]

Exploring high performance flexible thermoelectric materials with biopolymer hybrids fulfills the concept of green energy produced by green materials. The power generation ability of a thermoelectric (TE) device is strongly related to the thermoelectric power factor and the electrical conductivity of TE materials. However, it is very challenging to have a high power factor of >2000 μW m−1 K−2 together with a high electrical conductivity of >1000 S cm−1 in biopolymer-based TE materials since biopolymers are typically non-conductive. In this work, we reported a high power factor of >2500 μW m−1 K−2 with a high electrical conductivity of about 7450 S cm−1 which was achieved in biopolymer and carbon nanotube (CNT) hybrids at a relatively low CNT concentration of 33.3 wt%. This power factor is comparable to or even larger than that of many state-of-the-art only CNT films/fibers, and even inorganic TE films, such as Bi2Te3 films. The reason for the high power factor accompanied by a high electrical conductivity is attributed to the anisotropic electrical conductivity and isotropic Seebeck coefficient of the one-dimensional CNTs. Besides, the flexible films were pretty stable after being bent 10000 times, or washed 220 times, or wiped 5000 times. Such flexible and green TE materials with high performance are promising for future green energy harvesting. [ABSTRACT FROM AUTHOR]

Background: To evaluate the association of preoperative vitamin D levels with postoperative hypocalcaemia after total thyroidectomy. Methods: The medical records of patients who underwent total thyroidectomy between May 2020 and January 2022 and who had a documented preoperative serum 25-hydroxyvitamin D (25-OHD) concentration were retrospectively reviewed. Vitamin D levels were categorized into four groups: <10 ng/mL (severe vitamin D deficiency), 10–20 ng/mL (vitamin D deficiency), 20–30 ng/mL (vitamin D insufficiency), and > 30 ng/mL (vitamin D sufficiency). Multivariate logistic regression was performed to analyse the association of vitamin D levels with the risk of hypocalcaemia after controlling for potential confounding factors. Results: A total of 196 patients were included in this study. Of these, 47 (24.0%) had preoperative 25-OHD < 10 ng/mL, 62 (31.6%) had 25-OHD of 10–20 ng/mL, 51 (26.0%) had 25-OHD of 20–30 ng/mL and the remaining 36 (18.4%) had 25-OHD > 30 ng/mL. The incidence of postoperative hypocalcemia was highest in the group of patients with severe vitamin D deficiency (42.6% and 23.4% for postoperative laboratory and symptomatic hypocalcaemia, respectively), followed by the group with vitamin D deficiency (29.0% and 16.1%), the group with vitamin D insufficiency (19.6% and 5.9%) and the group with vitamin D sufficiency (5.6% and 2.8%). Multivariate logistic regression indicated that the odds of postoperative laboratory hypocalcaemia for patients with severe vitamin D deficiency and vitamin D deficiency were 13.20 times (95% CI: 2.69–64.79, P < 0.01) and 6.32 times (95% CI: 1.32–30.28, P = 0.02) greater than for those with vitamin D sufficiency, respectively; while the odds of symptomatic hypocalcaemia for patients with severe vitamin D deficiency was 10.18 times (95% CI: 1.14–90.86, P = 0.04) greater than for those with vitamin D sufficiency. Conclusion: Preoperative vitamin D deficiency (< 20 ng/mL), especially severe vitamin D deficiency (< 10 ng/mL), is an independent predictive factor of postoperative hypocalcaemia after total thyroidectomy. [ABSTRACT FROM AUTHOR]

Chiral metasurfaces with pronounced reflective chiroptical responses have drawn extensive attention as they can offer great opportunities for various chirality‐related applications. However, their fascinating potential are restrained by limited chiroptical responses, relatively complex design principle, and fabrication strategy. Herein, a concise and general design principle to develop out‐of‐plane reflective chiral metasurfaces, empowered with the maximum theoretical circular dichroism (CD), is theoretically proposed and experimentally demonstrated. The designed out‐of‐plane chiral metasurfaces operating in the terahertz (THz) region are flexibly fabricated via a simple, scalable, low‐cost and lithography‐free fabrication strategy by integrating a three‐dimensional (3D) printing technique. Finally, the methodological stabilities and the strong chiroptical responses of proposed chiral metasurfaces are validated experimentally. From the general design principle, simple fabrication strategy as well as maximum chiroptical responses of proposed reflective chiral metasurfaces, it can be envisaged that these findings may overcome the difficulties in design, optimization, and fabrication for reflective chiral metasurfaces and provide promising potentials for various chirality‐related applications in emerging THz technologies, such as chiral sensing, imaging, spectroscopy and polarimetry. [ABSTRACT FROM AUTHOR]

Scholars usually ignore the non-equilibrium condensing effects in turbulence-model comparative studies on supersonic steam ejectors. In this study, a non-equilibrium condensation model considering real physical properties was coupled respectively with seven turbulence models. They are the k-ε Standard, k-ε RNG, k-ε Realizable, k-ω Standard, k-ω SST, Transition SST, and Linear Reynolds Stress Model. Simulation results were compared with the experiment results globally and locally. The complex flow phenomena in the steam ejector captured by different models, including shock waves, choking, non-equilibrium condensation, boundary layer separation, and vortices were discussed. The reasons for the differences in simulation results were explained and compared. The relationship between ejector performance and local flow phenomena was illustrated. The novelty lies in the conclusions that consider the non-equilibrium condensing effects. Results show that the number and type of shock waves predicted by different turbulence models are different. Non-equilibrium condensation and boundary layer separation regions obtained by various turbulence models are different. Comparing the ejector performance and the complex flow phenomena with the experimental results, the k-ω SST model is proposed to simulate supersonic steam ejectors. [ABSTRACT FROM AUTHOR]

Leaf nutrient content and its stoichiometric relationships (N/P ratio) are essential for photosynthesis and plant growth and development. Previous studies on leaf nutrient-related functional traits have mainly focused on the species level and regional scale, but fewer studies have investigated the distribution patterns of the leaf N and P contents (LN, LP) and N/P ratios (N/P) in communities and their controlling factors at a large scale; therefore, we used LN, LP, and N/P data at 69 sites from 818 forests in China. The results showed significant differences (p < 0.05) in the LN, LP, and N/P at different life forms (tree, shrub, and herb). Neither LN, LP, nor N/P ratios showed significant patterns of latitudinal variation. With the increase in temperature and rainfall, the LN, LP, and leaf nutrient contents increased significantly (p < 0.001). Across life forms, LN at different life forms varied significantly and was positively correlated with soil P content (p < 0.001). The explanatory degree of climatic factors in shaping the spatial variation patterns of LN and N/P was higher than that of the soil nutrient factors, and the spatial variation patterns of the leaf nutrient traits of different life forms were shaped by the synergistic effects of climatic factors and soil nutrient factors. [ABSTRACT FROM AUTHOR]

Smart wearable market is burgeoning, and flexible energy storage is crucial to cope with its development. The commonly‐used metal‐based current collectors are heavy with limited flexibility. Other carbon‐based current collectors are expensive and fragile. Moreover, the poor interface between active material and current collector leads to unsatisfactory stability. Herein, these two issues are attempted to be solved by using cheap and lightweight polyester‐based fabrics as well as in‐situ growth. A deposited thin layer of nickel on the fabrics not only enhances the conductivity, but also serves as the sacrificial precursor for the growth of active materials. Thus, intimate contact is secured via chemical bonding. The electrode with ternary (metal‐inorganic‐organic) component shows excellent electrochemical performance. Namely, high areal capacity is realized (2.2 C cm−2 at 2 mA cm−2), which is far superior to its rigid nickel‐foam‐based counterpart. Furthermore, an all‐solid‐state supercapacitor device was assembled. The device provides an areal capacity of 2.03 C cm−2 at the current density of 2 mA cm−2. It realizes an energy density of 0.45 mWh cm−2 when the power density is 1.6 mW cm−2. This work offers a feasible and cost‐efficient way for fabricating electrode materials with excellent performance for portable supercapacitors. [ABSTRACT FROM AUTHOR]

Hashimoto's thyroiditis (HT) is the main cause of hypothyroidism. We develop a deep learning model called HTNet for diagnosis of HT by training on 106,513 thyroid ultrasound images from 17,934 patients and test its performance on 5051 patients from 2 datasets of static images and 1 dataset of video data. HTNet achieves an area under the receiver operating curve (AUC) of 0.905 (95% CI: 0.894 to 0.915), 0.888 (0.836–0.939) and 0.895 (0.862–0.927). HTNet exceeds radiologists' performance on accuracy (83.2% versus 79.8%; binomial test, p < 0.001) and sensitivity (82.6% versus 68.1%; p < 0.001). By integrating serologic markers with imaging data, the performance of HTNet was significantly and marginally improved on the video (AUC, 0.949 versus 0.888; DeLong's test, p = 0.004) and static-image (AUC, 0.914 versus 0.901; p = 0.08) testing sets, respectively. HTNet may be helpful as a tool for the management of HT. Hashimoto's thyroiditis (HT) is the main cause of hypothyroidism. Here the authors develop a deep learning model for diagnosis of HT on a large multi-site dataset including image and video data. [ABSTRACT FROM AUTHOR]

The complex flow phenomena in a three-dimensional supersonic steam ejector were simulated with a non-equilibrium condensation model including real physical properties in different pressure conditions. The different working conditions include discharge pressure, motive pressure, and suction pressure. The influence of different pressures on shock waves in the steam ejector was investigated comprehensively. The intrinsic causes of shock wave variation with pressure conditions were explained in detail. The results show that the width of the primary shock train region expand with an increase in the motive pressure or a decrease in suction pressure. The diamond shock waves move downstream with an increase in motive pressure or a decrease in suction pressure. The shocking position in the diffuser moves upstream until it reaches the diffuser entrance with an increase in discharge pressure or a decrease in motive pressure or suction pressure. The intensity and number of oblique shock waves in the diffuser increase with an increase in motive pressure and suction pressure or a decrease in discharge pressure. The existence of only one shock wave in the diffuser is a necessary and insufficient condition for the ejector to enter a double choking mode. [ABSTRACT FROM AUTHOR]

Sodium hybrid supercapacitors (Na‐HSCs) are regarded as one promising electrochemical energy storage device, because of the low price of sodium, prolonged life cycle, and high‐energy/power density. Nonetheless, the imparity between the fast capacitive reactions at cathode and the sluggish Faradaic reactions at the anode leads to an imbalance in the electrochemical reaction kinetics, limiting the development of Na‐HSCs. Therefore, it is urgent to develop suitable anode materials for performance‐enhanced Na‐HSCs. Herein, sandwich‐shell‐structured CoMn2O4/C hollow spheres are synthesized by a facile hydrothermal reaction and subsequent calcination, where mesoporous carbon hollow spheres (CHSs) serve as nonsacrificial hard templates. CHSs with numerous mesoporous channels are beneficial for the penetration of reactant ions. Therefore, CoMn2O4 nanosheets are successfully deposited on the inner and outer surfaces of CHSs, generating sandwich‐shell‐structured CoMn2O4/C hollow spheres. Benefiting from the unique design, CoMn2O4/C HSs exhibit excellent sodium storage performance, including a high‐specific capacity of 290 mAh g–1 at 0.1 A g–1 and prolonged cycling durability. A Na‐HSC assembled by CoMn2O4/C HSs anode and activated carbon cathode exhibits a high‐energy density (265 Wh kg–1) and a wide‐operating voltage range (0.01–4.0 V). [ABSTRACT FROM AUTHOR]

Lithium‐sulfur batteries, as viable options for energy storage, have gained popularity because of their high energy density. However, the poor conductivity of sulfur and Li2S, as well as the shuttling effect of lithium polysulfides, seriously limits their commercialization. Herein, cobalt chalcogenides (Co3O4, CoS, and Co3Se4) supported by reduced graphene oxide are synthesized as the electrode materials, which feature high conductivity, rapid kinetic conversion, and catalytic effect. Based on complementary experimental outputs and advanced computation, it is revealed that the change in anion results in distinctive performance. Among them, the cathode material based on Co3Se4/reduced graphene oxide is the best. The reasons can be ascribed to the conductive and catalytic improvement. This comparative study provides guidelines in the design of lithium‐sulfur batteries via the meticulous regulation of the anions. [ABSTRACT FROM AUTHOR]

Photocatalytic conversion of CO2 into useful products is a promising technology from environmental and economic viewpoints. However, the efficiency of current photocatalytic materials is still unsatisfactory. In this work, a robust S‐scheme heterojunction composed of 3D ZnO hollow spheres wrapped by 2D g‐C3N4 layers is fabricated. The electrostatic attraction between both components not only facilitates the exfoliation of g‐C3N4 layers but also strengthens the photocatalyst framework. The prepared g‐C3N4/ZnO photocatalyst afforded an enhanced CH4 production rate, which is ≈40 and 7 times higher than those of pure ZnO and g‐C3N4, respectively. The improved activity is attributed to the extended light absorption and suppressed charge carrier recombination. Moreover, apart from traditional techniques, electron paramagnetic resonance (EPR) is used to probe charge movement in the fabricated S‐scheme heterojunction. An observable shift of the relevant EPR peak is noticed after the construction of g‐C3N4/ZnO heterostructure, indicating the electron transfer process. This study sheds light on S‐scheme heterojunctions as efficient candidates for CO2 photocatalytic conversion. [ABSTRACT FROM AUTHOR]

Artificial photosynthesis by CO2 photoreduction is an ideal channel for mitigating the greenhouse effect and energy crises. Nevertheless, its efficiency is still low due to severe charge recombination and sluggish kinetics. Herein, an S‐scheme BiOBr/NiO heterojunction, composed of two kinds of p‐type semiconductors, exhibits enhanced CO2 photoreduction activity. Enhanced light absorption and specific surface area are attributable to NiO nanosheets with hierarchical porous structures. Results from in situ irradiated X‐ray photoelectron spectroscopy and work function calculation manifest that the photoexcited electrons transfer from BiOBr to NiO via the S‐scheme mechanism. And charge separation and a strong redox ability are simultaneously realized. In situ diffuse reflectance infrared Fourier transform spectra unveil complex intermediates in CO2 photoreduction. This work presents a novel understanding for the CO2 photoreduction mechanism of S‐scheme heterojunctions built by p‐type semiconductors by integrating in situ monitoring techniques with density functional theory calculation. [ABSTRACT FROM AUTHOR]