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This study reports for the first time the successful synthesis of a novel series of Ni2Fe1+xGe1−x (x = 0.25, 0.50, 0.75, 0.90) polycrystalline alloy materials with L21 austenite structure using the mechanical alloying method. Notably, the Ni2Fe1+xGe1−x alloys demonstrate excellent electromagnetic wave absorption performance across the entire 2–18 GHz frequency range, and by adjusting the composition ratio of iron and germanium, it is possible to effectively regulate their complex permittivity (εr$\left(\epsilon\right)_{\text{r}}$) and permeability (μr$\left(\mu\right)_{\text{r}}$), thereby adjusting the reflection loss. All Ni2Fe1+xGe1−x samples show an effective electromagnetic wave absorption effect of more than −10 dB, indicating that 90% of the electromagnetic waves are efficiently absorbed. Among them, the Ni2Fe1.5Ge0.5 sample achieves an outstanding −43.5 dB reflection loss at 3.2 GHz, and the maximum effective absorption bandwidth reaches 5.8 GHz (11.8–17.6 GHz) with just a 1.6 mm thickness, fully covering the Ku band. This excellent absorption ability comes from the strong ability of the material to reduce signal strength and its perfect impedance matching. This study first shows the high potential of Ni2Fe1+xGe1−x ferromagnetic alloys as effective, wide‐range electromagnetic wave absorbers. It suggests the ferromagnetic Ni2Fe1+xGe1−x alloys hold promise as appealing candidates for broadband and high‐efficiency electromagnetic wave absorption. [ABSTRACT FROM AUTHOR]

Zinc‐based batteries are emerging as the most promising candidates for large‐scale energy storage devices due to their low cost, high safety, and long‐term storage. However, zinc‐based batteries encounter challenges stemming from undesirable side reactions and zinc dendrites on the anode, as well as dissolution on the cathode. Owing to their extremely small size, substantial surface functional groups, and adjustable structure, carbon dots (CDs) present considerable benefits in augmenting coulombic efficiency, expanding cycle life, and enhancing the rate functionality of zinc‐based batteries. Herein, this review delves into the surface modification and morphological regulation of batteries elements by CDs, CDs composites, and CDs derivatives. Moreover, it systematically encapsulates the application of CDs in zinc‐based batteries, underscoring the pivotal role of CDs in the advancement of electrode technology. Finally, the review highlights the impediments and proposes potential avenues for utilizing CDs in zinc‐based batteries. This review aims to facilitate the development of superior solutions and provide scientific insights into energy storage technologies. [ABSTRACT FROM AUTHOR]

Rational: Aconiti Lateralis Radix Praeparata (AC) is a traditional Chinese medicine with a long history of use. However, the current research on the material basis of AC and its processed products is still not comprehensive, especially the changes in lipo‐diterpenoid alkaloids (LDAs) that can be hydrolyzed into diester‐diterpenoid alkaloids in AC before and after processing. This study aimed to provide material basis guidance for the clinical use of AC and its processed products by comprehensively analyzing the changes in substances between AC and its processed products. Methods: An ultra‐high‐performance liquid chromatography with quadrupole time‐of‐flight mass spectrometry (UHPLC/Q‐TOF‐MS/MS) approach was optimized to chemical profiling. The MS data were processed using molecular networking combined with the in‐house library database to fast characterize the compounds. Multivariate statistical methods were adopted to determine the dissimilarities of components in AC and its processed products. Results: A total of 310 compounds were tentatively identified from AC, including 109 potential new alkaloids, of which 98 were potential novel LPAs. A metabolomics approach was applied to find the characteristic marker components. As a result, 52 potential chemical markers were selected to distinguish the AC samples of different extraction methods and 42 potential chemical markers for differentiating between AC and its processed products were selected. Conclusion: The results indicate that UHPLC/Q‐TOF‐MS/MS and Global Natural Products Social Molecular Networking coupled with multivariate analysis strategies was a powerful tool to rapidly identify and screen the chemical markers of alkaloids between the AC samples and its processed products. These results also indicate that the toxicity of water extracts of AC and its processed products were decreased. This research not only guides the clinical safe use of AC and its processed products, but also extends the application of the molecular networking strategy in traditional herbal medicine. [ABSTRACT FROM AUTHOR]

Herein, a simple strategy for fabricating amorphous Co2FeGe nanoflakes by tuning the milling time with mechanical alloying method to enhance the microwave absorption capabilities is presented. These alloys exhibit soft magnetic properties characterized by high saturation magnetization and low coercivity. The enhancement of polarization and resonance effects, leading to improved magnetic and dielectric loss, is attributed to the refinement of crystalline size and the substantial aspect ratio of flaky particles. The minimum reflection loss reaches −48.6 dB at 4.92 GHz with an effective absorption bandwidth of 2.88 GHz in the C‐band. Due to its high Curie temperature, Co2FeGe exhibits considerable potential for maintaining highly efficient microwave absorption capabilities under high‐temperature conditions, thereby providing a novel perspective and technical means for the development of new high‐temperature‐resistant, high‐performance microwave‐absorbing materials. This is expected to play a significant role in future high‐temperature electronic countermeasure systems. [ABSTRACT FROM AUTHOR]

Sodium metal anode is considered the most promising alternative to lithium due to its cost‐effectiveness and widespread availability. To realize its practical applications, numerous strategies have been devised in metallic Na and electrolyte to enhance the cycle life. However, the improvements in 2D current collector in ester‐based electrolyte remain limited. Herein, a two‐alloys‐layer modified current collector (Na15Sn4/Cu6Sn5/Cu) has been constructed through electrodeposition and sodiation processes. The Na15Sn4/Cu6Sn5 alloys‐layer guarantees the dense plating of Na and establishes a credible connection between Na and substrate. The failure of sodium anode is attributed to the depletion of ester‐based electrolyte resulting from their side reactions, which could be mitigated on Na15Sn4 surface. Thus, the asymmetric cell, containing merely 100 µL electrolyte, achieves efficient Na plating/stripping for 110 times with an average Coulombic efficiency of 94.9%, which is superior than those reported using excessive fluorine‐rich electrolytes. The full cell consisting of an anode with 3 mAh cm−2 of Na on Na15Sn4/Cu6Sn5/Cu and a Na3V2(PO4)3 cathode demonstrates a capacity retention rate of 96% after 200 cycles at 1.0 C. By improving the Coulombic efficiency solely through the modified copper foil, this work provides a new route for the practical application of Na anode in ester‐based electrolytes. [ABSTRACT FROM AUTHOR]

Hydrovoltaic devices (HDs) that convert ubiquitous environmental energy via water evaporation serves as a prospective technology for renewable power schemes. However, it remains a grand challenge to perform controllable and stable modulation of hydrovoltaic power generation for multi‐scenario practical applications. Here, a ferroelectric‐field assisted silicon HD is proposed, which sandwiches an ultrathin polarizable polymer between nanostructured silicon and the top electrode, constituting an asymmetric heterojunction designed to clinch well‐regulated and robust electrical signal output. Tunable modulation of the internal electric field at the silicon/top electrode interface can be realized by facilely aligning the polarization orientation of the ferroelectric domains, thus dominating the silicon energy band bending and controlling the ultimate electrical signal. Upon effective forward polarization, the interfacial dipoles can build a stronger asymmetric electric field, which allows an efficient sweep of the charges out of the heterojunction. Accordingly, the resulting device clinches to yield a considerably modulated voltage of 1.04 V, nearly three‐fold modulation over the reverse polarization one. As prospective applications, multifunctional sensing platforms including the self‐sufficient environmental temperature detector, intelligent water‐level alarm system, and automatic‐manual dual‐mode irrigation control system are demonstrated. This work exhibits the unique characteristics of ferroelectric HDs with tunable electrical performance. [ABSTRACT FROM AUTHOR]

Accurate spatiotemporal estimation of non‐methane volatile organic compounds (NMVOCs) plays a pivotal role in establishing sophisticated early warning systems and formulating strategies to combat air pollution. Despite these critical applications, robust estimation of high spatiotemporal resolution NMVOCs concentrations remains a challenge. In this study, we develop a space‐time Light Gradient Boosting Machine (STLGB) model, which successfully renders hourly maps of NMVOCs concentrations across Shanghai from 2019 to 2022 by integrating spatiotemporal information. After extensive training, the STLGB model demonstrates remarkable estimation performance for NMVOCs, accounting for multiple spatiotemporal variables (R2 = 0.92, RMSE = 34.52 ppb). With the developed model, we provide first high‐resolution (1 km) hourly NMVOCs concentration maps, uncovering previously overlooked spatiotemporal variations. Further, SHapley Additive exPlanation (SHAP) regression values reveal significant local interpretation capabilities of the STLGB model, emphasizing the strong influence of emissions on NMVOCs estimation, whilst acknowledging the important contribution of space and time term. Our study of the pandemic lockdown further showcases the model's adaptability to unique events influenced by policy changes. The superior performance of the STLGB model, with its minimal computational memory requirements and faster speed, makes it an ideal tool for air pollutant estimation, adaptable to any region with NMVOCs monitoring capabilities. Plain Language Summary: Non‐methane Volatile organic compounds (NMVOCs) are significant air pollutants that have severe effects on health and the environment. Despite the availability of VOCs monitoring stations that can provide data with good temporal resolution, the low spatial resolution of these stations remains a challenge. Accurate estimation of NMVOCs concentrations requires new methods to address these spatial resolution issues. In recent years, machine learning‐based models have emerged as a promising alternative for air pollution estimations. However, research on high‐resolution mapping of NMVOCs concentrations using machine learning models is limited. This study provides the first predicted spatial distribution of hourly NMVOCs map deduced from sparse observations using the machine learning models. We developed a space‐time LightGBM model to estimate NMVOCs concentrations at 1 km spatial and hourly temporal resolution in Shanghai. Meanwhile, we use the shapely additive explanations to quantify and visualize the complex relationships between the input variables in the model. Moreover, we also offers an alternative solution to air pollution modeling with regard to unusual events (such as the COVID‐19 lockdown). Key Points: A space‐time LightGBM (STLGB) model in machine learning is used to estimate NMVOCs reliablyHourly NMVOCs maps were produced at 1 km resolution by the STLGB modelThe STLGB model shows good performance with cross‐validation R2 of 0.92 [ABSTRACT FROM AUTHOR]

Summary: The clinical outcome of obstructive sleep apnea in patients with acute coronary syndrome in relation to hyperuricemia is still unclear. We aimed to explore the clinical prognosis of obstructive sleep apnea in patients with acute coronary syndrome in relation to hyperuricemia status. This was a prospective cohort study. We included consecutively eligible patients with acute coronary syndrome who underwent cardiorespiratory polygraphy between June 2015 and January 2020. According to apnea–hypopnea index ≥ 15 events per hr and serum uric acid level, the population was divided into four groups: hyperuricemia with obstructive sleep apnea; hyperuricemia with non‐obstructive sleep apnea; no hyperuricemia with obstructive sleep apnea; and no hyperuricemia with non‐obstructive sleep apnea. The primary endpoint was major adverse cardiovascular and cerebrovascular events, including cardiovascular death, myocardial infarction, stroke, ischaemia‐driven revascularization, and readmission for unstable angina or heart failure. Spearman correlation analysis and Cox regression model were mainly used to estimate the data. The median follow‐up was 2.9 years. Among 1925 patients with acute coronary syndrome, 29.6% had hyperuricemia and 52.6% had obstructive sleep apnea. Uric acid was negatively correlated with minimum arterial oxygen saturation and mean arterial oxygen saturation, and positively correlated with apnea–hypopnea index, oxygen desaturation index and the duration of time with arterial oxygen saturation < 90% (p < 0.001). During 2.9 (1.5, 3.6) years of follow‐up, obstructive sleep apnea was associated with an increased risk of major adverse cardiovascular and cerebrovascular events in patients with hyperuricemia (23.5% versus 13.4%; adjusted hazard ratio: 1.834; 95% confidence interval: 1.192–2.821, p = 0.006), but not in patients without hyperuricemia (21.9% versus 19.2%; adjusted hazard ratio: 1.131; 95% confidence interval: 0.880–1.453, p = 0.336). There was a correlation between uric acid levels and sleep respiratory indicators. Obstructive sleep apnea was associated with increased risk of major adverse cardiovascular and cerebrovascular events in patients with acute coronary syndrome with hyperuricemia, but not in patients without hyperuricemia. [ABSTRACT FROM AUTHOR]

In nature, chameleons and insect wings show characteristics of actively tunable and passively off/on structural colors, respectively, which is crucial for them to camouflage and survival. Inspired by these, photonic crystal (PC) gels possessing chameleon's nonclose‐packing structures can actively mimic the reversible off/on characteristics of the structural colors of insect wings are designed. The PC gels with outstanding tailorable, bendable, and twistable properties are prepared by nonclose‐assembling silica particles in polymers and swelling in solvents. Interestingly, the PC gels exhibit high transparency (>95%) in water because of the matching of the refractive index (Δn = 0) but show brilliant and tunable structural colors in other solvents due to the Δn ≠ 0. The switching between the off/on colors can be completed in tens of seconds. Based on these advantages, the PC gels are used to actively camouflage and fabricate invisible patterns that are transparent in water but revealable in other solvents. This work offers a straightforward and efficient way to build PC gels with solvents‐responsive off/on color characteristics, showing great potential in camouflage, anticounterfeiting, and optical devices. [ABSTRACT FROM AUTHOR]

The tremendous growth of Internet of Medical Things has led to a surge in medical user data, and medical data publishing can provide users with numerous services. However, neglectfully publishing the data may lead to severe leakage of user's privacy. In this article, we investigate the problem of data publishing in Internet of Medical Things with privacy preservation. We present a novel system model for Internet of Medical Things user data publishing which adopts the proposed multiple partition differential privacy k -medoids clustering algorithm for data clustering analysis to ensure the security of user data. Particularly, we propose a multiple partition differential privacy k -medoids clustering algorithm based on differential privacy in data publishing. Based on the traditional k -medoids clustering, multiple partition differential privacy k -medoids clustering algorithm optimizes the randomness of selecting initial center points and adds Laplace noise to the clustering process to improve data availability while protecting user's privacy information. Comprehensive analysis and simulations demonstrate that our method can not only meet the requirements of differential privacy but also retain the better availability of data clustering. [ABSTRACT FROM AUTHOR]

Summary: Lithium (Li) metal anodes can be inevitably corroded and destructed due to the direct contact with the liquid electrolyte. Here, a precast solid electrolyte interface (SEI) film is constructed based on poly(vinylidene‐co‐hexafluoropropylene) (PVDF‐HFP) matrix on a copper current collector to avoid side reactions between Li and electrolytes and further prevent dendrites growth. Lithium bis(oxalato)borate (LiBOB), SiC, and polyethylene oxide (PEO) are rationally hybridized, and their effects on the morphology, composition, strength, and other properties of the precast SEI film are studied through both physical and electrochemical characterizations. Due to the addition of LiBOB, SiC, and PEO, the structure and properties of the PVDF–HFP matrix have undergone a distinct change, which affects the cycle stability of the substrate. As a result, the cycling lifetime of the SEI film is increased from 61 to 295 cycles after adding an appropriate amount of LiBOB to the PVDF–HFP. Furthermore, the Li metal anode delivers a significantly improved life‐span of 452 cycles at 1.0 mA·cm−2, 1.0 mAh·cm−2 by virtue of the robust SEI with SiC and PEO added. Meantime, the Coulombic efficiency of the cell has also increased from 95.0% to more than 99.0%. The morphology and composition characterization results show that the SEI structure gradually collapses during cycling, which are found to arise from the formation of loosely connected Li2CO3, LiF, and dilapidated PVDF–HFP mixture. The deteriorative artificial SEI also induces the disconnected electrical contact, and as such the impedance significantly increases, resulting in eventual failure of the Li metal anode. [ABSTRACT FROM AUTHOR]

A facile and controllable dual‐carbon microreactor approach has been developed to prepare graphene and amorphous carbon co‐decorated LiFePO4 (LFP) nanocomposites (G/LFP@C). Physical characterizations demonstrate that the particle size of the restricted LFP crystals is ≈30–50 nm, which are well proportioned and well anchored on the surface of graphene and completely coated by the amorphous carbon layers. The electrochemical data demonstrate the impressive electrochemical performances of the G/LFP@C composite and its application potential as a cathode material of lithium ion batteries (LIBs). Particularly, the large specific capacity (161.3 mAh g−1 at 0.2 C), superior rate property (93.8 mAh g−1 at 20 C), and outstanding cycling stability (97.3% capacity retention over 1000 cycles at 10 C) are simultaneously realized for G/LFP@C because of the optimized electrochemical reaction kinetics with effective dual‐carbon co‐constructed conductive network and abundant active sites. It is believe that this work not only supplies unique in sights into the reasonable design of LFP materials for favorable property LIBs, but also holds great potential for the energy storage market. [ABSTRACT FROM AUTHOR]

Lithium–sulfur batteries (LSB) are considered to have great research value and application prospects in the future due to their high theoretical energy density, inexpensive characteristics, and environmental friendliness. However, the poor electronic conductivity, large volume change, and shuttle effect of the sulfur cathode seriously hinder the commercial application of LSBs. Herein, a graphene‐modified mesoporous amorphous FePO4 (G/FP) binary host is synthesized using a mild one‐step hydrothermal method. The FePO4 (FP) component with strong polarity plays a crucial role in chemical adsorption and conversion of polysulfides, thus inhibiting the shuttle effect during the cycle process. The graphene (G) framework ensures the electronic conductivity and physically adsorbs polysulfides to improve the utilization of active sulfur. The reasonable porous structure of the G/FP matrix guarantees fast Li+ transport and more electrochemical reactive sites, thereby enabling the excellent electrochemical performance of the G/FP/S cathode. The prepared G/FP/S cathode with a high initial discharge specific capacity of 1469.5 mAh g−1 delivers a stable capacity of 840.7 mAh g−1 at 0.2 C after 300 cycles and 656.7 mAh g−1 at 1.0 C after 800 cycles as well as an excellent rate performance (651.8 mAh g−1 at 5.0 C) at a relatively large sulfur loading of 3.1 mg cm−2. [ABSTRACT FROM AUTHOR]

Objective Methods Results Conclusions To explore the relationship between adipose tissue deposition and triglyceride‐glucose (TyG) index, an indicator clinically used to assess insulin resistance (IR), in middle‐aged and elderly women using quantitative computed tomography (QCT) and MRI mDIXON‐Quant sequence.All participants underwent quantitative computed tomography (QCT) and MRI mDIXON‐Quant examination and calculated the TyG index based on the fasting blood glucose and triacylglycerol. Bounded by the median TyG index, all participants were divided into low TyG group and high TyG group. Visceral fat mass (VFM) and subcutaneous fat mass (SFM) were measured on QCT images. Hepatic proton density fat fraction (H‐PDFF), pancreatic proton density fat fraction (P‐PDFF), and lumbar bone marrow fat fraction (L‐BMFF) were measured on MRI mDIXON‐Quant images.Adjusting for age and body mass index (BMI), TyG was moderately positively correlated with H‐PDFF, and r/P was 0.416/<0.001, TyG index was weakly positively correlated with VFM and P‐PDFF, and r/P were 0.385/<0.001 and 0.221/0.030. There was a difference of VFM, H‐PDFF, and P‐PDFF between low TyG group and high TyG group (P < 0.05). Adjusting for age and BMI, VFM, and H‐PDFF were the risk factors of high TyG, and H‐PDFF was the independent risk factor of high TyG.VFM and H‐PDFF were the risk factors of IR, and H‐PDFF was the independent risk factor. Early identification and active treatment of adipose tissue deposition, especially hepatic fat deposition, may reserve and delay the progression of IR and even metabolic syndrome. [ABSTRACT FROM AUTHOR]

Aqueous Zn‐ion batteries (AZIBs) are promising energy storage systems due to their low cost, excellent safety, and environmental friendliness. However, challenges like uncontrollable dendrite growth and side reactions during battery operation limit their commercialization. Addressing these issues requires regulating ion deposition behavior at the anode/electrolyte interface. The electrostatic shielding effect, which leverages the interplay between electric potential and ionic motion, provides a unique mechanism to inhibit zinc dendrites and side reactions effectively. Despite significant progress in understanding electrostatic shielding in AZIBs, a comprehensive summary of its effects is still lacking. This paper first reviews the primary challenges in AZIBs and then describes how the electrostatic shielding effect can optimize their performance. Existing strategies for achieving electrostatic shielding through anode structure optimization and electrolyte optimization‐are classified and analyzed. Finally, the review summarizes current electrostatic shielding strategies for stabilizing zinc anodes, identifies existing challenges, and discusses the future potential, and for this approach in AZIBs. [ABSTRACT FROM AUTHOR]