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Kupffer cells (KCs) are key regulators of liver immunity composing the principal part of hepatic macrophages even body tissue macrophages. They reside in liver sinusoids towards portal vein. The micro-environment shapes KCs unique immunosuppressive features and functions. KCs express specific surface markers that distinguish from other liver macrophages. By engulfing gut-derived foreign products and apoptotic cells without triggering excessive inflammation, KCs maintain homeostasis of liver and body. Heterogeneity of KCs has been identified in different studies. In terms of the origin, adult KCs are derived from progenitors of both embryo and adult bone marrow. Embryo-derived KCs compose the majority of KCs in healthy and maintain by self-renewal. Bone marrow monocytes replenish massively when embryo-derived KC proliferation are impaired. The phenotype of KCs is also beyond the traditional dogma of M1-M2. Functionally, KCs play central roles in pathogenesis of acute and chronic liver injury. They contribute to each pathological stage of liver disease. By initiating inflammation, regulating fibrosis, cirrhosis and tumor cell proliferation, KCs contribute to the resolution of liver injury and restoration of tissue architecture. The underlying mechanism varied by damage factors and pathology. Understanding the characteristics and functions of KCs may provide opportunities for the therapy of liver injury. Herein, we attempt to afford insights on heterogeneity and functions of KCs in liver injury using the existing findings.

Lithium metal has shown great promise as an anode material for high-energy storage systems, owing to its high theoretical specific capacity and low negative electrochemical potential. Unfortunately, uncontrolled dendritic and mossy lithium growth, as well as electrolyte decomposition inherent in lithium metal-based batteries, cause safety issues and low Coulombic efficiency. Here we demonstrate that the growth of lithium dendrites can be suppressed by exploiting the reaction between lithium and lithium polysulfide, which has long been considered as a critical flaw in lithium–sulfur batteries. We show that a stable and uniform solid electrolyte interphase layer is formed due to a synergetic effect of both lithium polysulfide and lithium nitrate as additives in ether-based electrolyte, preventing dendrite growth and minimizing electrolyte decomposition. Our findings allow for re-evaluation of the reactions regarding lithium polysulfide, lithium nitrate and lithium metal, and provide insights into solving the problems associated with lithium metal anodes. Lithium dendrite growth is a serious hazard in battery operations. Here, the authors show that when using lithium polysulfide and lithium nitrate as additives in ether-based electrolyte, a stable and uniform solid electrolyte interphase forms on the lithium surface, which prevents dendrite growth.

Nonaqueous sodium-based batteries are ideal candidates for the next generation of electrochemical energy storage devices. However, despite the promising performance at ambient temperature, their low-temperature (e.g., < 0 °C) operation is detrimentally affected by the increase in the electrolyte resistance and solid electrolyte interphase (SEI) instability. Here, to circumvent these issues, we propose specific electrolyte formulations comprising linear and cyclic ether-based solvents and sodium trifluoromethanesulfonate salt that are thermally stable down to −150 °C and enable the formation of a stable SEI at low temperatures. When tested in the Na||Na coin cell configuration, the low-temperature electrolytes enable long-term cycling down to −80 °C. Via ex situ physicochemical (e.g., X-ray photoelectron spectroscopy, cryogenic transmission electron microscopy and atomic force microscopy) electrode measurements and density functional theory calculations, we investigate the mechanisms responsible for efficient low-temperature electrochemical performance. We also report the assembly and testing between −20 °C and −60 °C of full Na||Na 3 V 2 (PO 4 ) 3 coin cells. The cell tested at −40 °C shows an initial discharge capacity of 68 mAh g −1 with a capacity retention of approximately 94% after 100 cycles at 22 mA g −1 . The low-temperature operation of non-aqueous sodium-based batteries is affected by the properties of the electrolyte. Here the authors propose specific electrolyte formulations that are thermally stable down to −150 °C and enable a stable electrode|electrolyte interface at low temperatures.

Lithium–sulfur batteries have attracted attention due to their six-fold specific energy compared with conventional lithium-ion batteries. Dissolution of lithium polysulfides, volume expansion of sulfur and uncontrollable deposition of lithium sulfide are three of the main challenges for this technology. State-of-the-art sulfur cathodes based on metal-oxide nanostructures can suppress the shuttle-effect and enable controlled lithium sulfide deposition. However, a clear mechanistic understanding and corresponding selection criteria for the oxides are still lacking. Herein, various nonconductive metal-oxide nanoparticle-decorated carbon flakes are synthesized via a facile biotemplating method. The cathodes based on magnesium oxide, cerium oxide and lanthanum oxide show enhanced cycling performance. Adsorption experiments and theoretical calculations reveal that polysulfide capture by the oxides is via monolayered chemisorption. Moreover, we show that better surface diffusion leads to higher deposition efficiency of sulfide species on electrodes. Hence, oxide selection is proposed to balance optimization between sulfide-adsorption and diffusion on the oxides. Metal oxides can suppress detrimental polysulfide shuttling in lithium-sulfur batteries, however selection criteria for oxide materials are still lacking. Here, the authors investigate polysulfide adsorption and diffusion on metal oxides and propose selection criteria based on balancing these two effects.

Sulfur is an exciting cathode material with high specific capacity of 1,673 mAh/g, more than five times the theoretical limits of its transition metal oxides counterpart. However, successful applications of sulfur cathode have been impeded by rapid capacity fading caused by multiple mechanisms, including large volume expansion during lithiation, dissolution of intermediate polysulfides, and low ionic/electronic conductivity. Tackling the sulfur cathode problems requires a multifaceted approach, which can simultaneously address the challenges mentioned above. Herein, we present a scalable, room temperature, one-step, bottom-up approach to fabricate monodisperse polymer (polyvinylpyrrolidone)-encapsulated hollow sulfur nanospheres for sulfur cathode, allowing unprecedented control over electrode design from nanoscale to macroscale. We demonstrate high specific discharge capacities at different current rates (1,179, 1,018, and 990 mAh/g at C/10, C/5, and C/2, respectively) and excellent capacity retention of 77.6% (at C/5) and 73.4% (at C/2) after 300 and 500 cycles, respectively. Over a long-term cycling of 1,000 cycles at C/2, a capacity decay as low as 0.046% per cycle and an average coulombic efficiency of 98.5% was achieved. In addition, a simple modification on the sulfur nanosphere surface with a layer of conducting polymer, poly(3,4-ethylenedioxythiophene), allows the sulfur cathode to achieve excellent high-rate capability, showing a high reversible capacity of 849 and 610 mAh/g at 2C and 4C, respectively.

For future applications in portable electronics, electric vehicles and grid storage, batteries with higher energy storage density than existing lithium ion batteries need to be developed. Recent efforts in this direction have focused on high-capacity electrode materials such as lithium metal, silicon and tin as anodes, and sulphur and oxygen as cathodes. Lithium metal would be the optimal choice as an anode material, because it has the highest specific capacity (3,860 mAh g –1 ) and the lowest anode potential of all. However, the lithium anode forms dendritic and mossy metal deposits, leading to serious safety concerns and low Coulombic efficiency during charge/discharge cycles. Although advanced characterization techniques have helped shed light on the lithium growth process, effective strategies to improve lithium metal anode cycling remain elusive. Here, we show that coating the lithium metal anode with a monolayer of interconnected amorphous hollow carbon nanospheres helps isolate the lithium metal depositions and facilitates the formation of a stable solid electrolyte interphase. We show that lithium dendrites do not form up to a practical current density of 1 mA cm –2 . The Coulombic efficiency improves to ∼99% for more than 150 cycles. This is significantly better than the bare unmodified samples, which usually show rapid Coulombic efficiency decay in fewer than 100 cycles. Our results indicate that nanoscale interfacial engineering could be a promising strategy to tackle the intrinsic problems of lithium metal anodes. Hollow carbon nanospheres form a stable solid electrolyte interphase on lithium metal anodes that suppresses dendrite growth and improves cycling Coulombic efficiency.

Fault diagnosis in large-scale systems presents significant challenges due to the complexity and high dimensionality of data, as well as the scarcity of labeled fault data, which are hard to obtain during the practical operation process. This paper proposes a novel approach, called Multi-Variable Meta-Transformer (MVMT), to tackle these challenges. In order to deal with the multi-variable time series data, we modify the Transformer model, which is the currently most popular model on feature extraction of time series. To enable the Transformer model to simultaneously receive continuous and state inputs, we introduced feature layers before the encoder to better integrate the characteristics of both continuous and state variables. Then, we adopt the modified model as the base model for meta-learning—more specifically, the Model-Agnostic Meta-Learning (MAML) strategy. The proposed method leverages the power of Transformers for handling multi-variable time series data and employs meta-learning to enable few-shot learning capabilities. The case studies conducted on the Tennessee Eastman Process database and a Power-Supply System database demonstrate the exceptional performance of fault diagnosis in few-shot scenarios, whether based on continuous-only data or a combination of continuous and state variables.

Ding Ma, Hui Wang, Xun Xu and colleagues report a genome-wide map of HPV integration sites in cervical cancer samples and cell lines. In addition to discovering new integration hot spots, the authors identify microhomology-mediated DNA repair as a likely mechanism by which HPV integrates into the human genome. Human papillomavirus (HPV) integration is a key genetic event in cervical carcinogenesis 1 . By conducting whole-genome sequencing and high-throughput viral integration detection, we identified 3,667 HPV integration breakpoints in 26 cervical intraepithelial neoplasias, 104 cervical carcinomas and five cell lines. Beyond recalculating frequencies for the previously reported frequent integration sites POU5F1B (9.7%), FHIT (8.7%), KLF12 (7.8%), KLF5 (6.8%), LRP1B (5.8%) and LEPREL1 (4.9%), we discovered new hot spots HMGA2 (7.8%), DLG2 (4.9%) and SEMA3D (4.9%). Protein expression from FHIT and LRP1B was downregulated when HPV integrated in their introns. Protein expression from MYC and HMGA2 was elevated when HPV integrated into flanking regions. Moreover, microhomologous sequence between the human and HPV genomes was significantly enriched near integration breakpoints, indicating that fusion between viral and human DNA may have occurred by microhomology-mediated DNA repair pathways 2 . Our data provide insights into HPV integration-driven cervical carcinogenesis.

Electrochemical CO 2 reduction to fuels necessitates multiple steps of electron and proton transfer. As one of the primary proton donors for CO 2 reduction, H 2 O is essential to regulating the reaction pathway and product selectivity. However, the coordinating nature of H 2 O and its influence are poorly understood due to challenges in identifying the precise structure of catalytic sites. Here, we employ a well-defined bismuth-based metal-organic framework material with molecularly precise active sites and ordered microporosity for in-depth mechanistic studies. The coordinated H 2 O on active sites promotes the adsorption of CO 2 and alleviates the sluggish proton supply via a protonated carbonic acid pathway involving a surface hydride transfer, which significantly promotes the adsorption and activation of CO 2 . This results in a 99% selectivity for CO 2 reduction to formic acid with a high turnover frequency of 21.1 s −1 . Leveraging the advantages of crystalline coordination frameworks in electrocatalysis, this work fills up a lacuna in our understanding of CO 2 hydrogenation/reduction and reinforces the importance of H 2 O to the advanced design of catalytic systems. H 2 O, a primary proton donor, governs CO 2 reduction pathways and regulates selectivity, yet its coordination effects remain elusive. By exploiting the long-range structural order and porosity of crystalline coordination frameworks, this work uncovers how coordinated H 2 O influences CO 2 reduction.

The concept of niche similarity is crucial for understanding species invasions. An in-depth understanding of different niches can aid in developing effective control strategies, not only at the community level but also in population interactions. In this study, we investigated the invasion of Spartina alterniflora in China by selecting nine major mangrove species along the Chinese coast. Utilizing an ensemble species distribution model (ESDM), we compared the niche characteristics of these mangroves with S. alterniflora . We found that S. alterniflora has a broad latitudinal adaptability (39.22–21.67˚N), significantly greater than the mangroves. Excoecaria agallocha has the largest potential distribution area (74,729 km 2 ), while Kandelia obovata shows the widest climatic adaptability (latitude: 30.85˚N to 18.19˚N). The ecological niches of the mangroves and S. alterniflora overlap (D.overlap: 0.015–0.254, Niche similarity index: 0.044–0.551), driven by different species-specific factors. K. obovata and S. alterniflora have the highest niche similarity due to the similarities in precipitation during the driest month and precipitation seasonality. Overall, mangroves in China are vulnerable to invasion by S. alterniflora . Strengthening mangrove protection is essential for their healthy development, especially under frequent extreme weather conditions, with a focus on protecting K. obovata .