Dimerization of assimilatory NADPH-dependent sulfite reductase reveals elements for diflavin reductase binding at a minimal interface.

Escherichia coli NADPH-dependent assimilatory sulfite reductase is responsible for fixing sulfur for incorporation into sulfur-containing biomolecules. The oxidoreductase is composed of two subunits, an NADPH, FMN, and FAD-binding diflavin reductase and an iron siroheme and Fe4S4-containing oxidase. How they interact has been an unknown for over 50 years because the complex is highly flexible, thus has been intransigent for traditional X-ray or cryo-EM structural analysis. Using a combination of the chameleon plunging system with a fluorinated lipid we overcame the challenge of preserving the minimal dimer between the subunits for high-resolution cryo-EM analysis. Here, we report the first structure of the complex between the reductase and oxidase, revealing how they interact in a minimal interface. Further, we determined the structural elements that discriminate between the pairing of a siroheme-containing oxidase with a diflavin reductase or a ferredoxin partner to channel the six electrons that reduce sulfite to sulfide.

5-hydroxymethylcytosines regulate gene expression as a passive DNA demethylation resisting epigenetic mark in proliferative somatic cells.

Enzymatic erasure of DNA methylation in mammals involves iterative 5-methylcytosine (5mC) oxidation by the ten-eleven translocation (TET) family of DNA dioxygenase proteins. As the most abundant form of oxidized 5mC, the prevailing model considers 5-hydroxymethylcytosine (5hmC) as a key nexus in active DNA demethylation that can either indirectly facilitate replication-dependent depletion of 5mC by inhibiting maintenance DNA methylation machinery (UHRF1/DNMT1), or directly be iteratively oxidized to 5-formylcytosine (5fC) and 5-carboxycytosine (5caC) and restored to cytosine (C) through thymine DNA glycosylase (TDG)-mediated 5fC/5caC excision repair. In proliferative somatic cells, to what extent TET-dependent removal of 5mC entails indirect DNA demethylation via 5hmC-induced replication-dependent dilution or direct iterative conversion of 5hmC to 5fC/5caC is unclear. Here we leverage a catalytic processivity stalling variant of human TET1 (TET1.var: T1662E) to decouple the stepwise generation of 5hmC from subsequent 5fC/5caC generation, excision and repair. By using a CRISPR/dCas9-based epigenome-editing platform, we demonstrate that 5fC/5caC excision repair (by wild-type TET1, TET1.wt), but not 5hmC generation alone (by TET1.var), is requisite for robust restoration of unmodified cytosines and reversal of somatic silencing of the methylation-sensitive, germline-specific RHOXF2B gene promoter. Furthermore, integrated whole-genome multi-modal epigenetic sequencing reveals that hemi-hydroxymethylated CpG dyads predominantly resist replication-dependent depletion of 5mC on the opposing strand in TET1.var-expressing cells. Notably, TET1.var-mediated 5hmC generation is sufficient to induce similar levels of differential gene expression (compared to TET1.wt) without inducing major changes in unmodified cytosine profiles across the genome. Our study suggests 5hmC alone plays a limited role in driving replication-dependent DNA demethylation in the presence of functional DNMT1/UHRF1 mechanisms, but can regulate gene expression as a bona fide epigenetic mark in proliferative somatic cells.

TET1 facilitates specification of early human lineages including germ cells.

Ten Eleven Translocation 1 (TET1) is a regulator of localized DNA demethylation through the conversion of 5-methylcytosine (5mC) to 5-hydroxymethylcytosine (5hmC). To examine DNA demethylation in human primordial germ cell-like cells (hPGCLCs) induced from human embryonic stem cells (hESCs), we performed bisulfite-assisted APOBEC coupled epigenetic sequencing (bACEseq) followed by integrated genomics analysis. Our data indicates that 5hmC enriches at hPGCLC-specific NANOG, SOX17 or TFAP2C binding sites on hPGCLC induction, and this is accompanied by localized DNA demethylation. Using CRISPR-Cas9, we show that deleting the catalytic domain of TET1 reduces hPGCLC competency when starting with hESC cultured on mouse embryonic fibroblasts, and this phenotype can be rescued after transitioning hESCs to defined media and a recombinant substrate. Taken together, our study demonstrates the importance of 5hmC in facilitating hPGCLC competency, and the role of hESC culture conditions in modulating this effect.

Mammalian DNA methylome dynamics: mechanisms, functions and new frontiers.

DNA methylation is a highly conserved epigenetic modification that plays essential roles in mammalian gene regulation, genome stability and development. Despite being primarily considered a stable and heritable epigenetic silencing mechanism at heterochromatic and repetitive regions, whole genome methylome analysis reveals that DNA methylation can be highly cell-type specific and dynamic within proximal and distal gene regulatory elements during early embryonic development, stem cell differentiation and reprogramming, and tissue maturation. In this Review, we focus on the mechanisms and functions of regulated DNA methylation and demethylation, highlighting how these dynamics, together with crosstalk between DNA methylation and histone modifications at distinct regulatory regions, contribute to mammalian development and tissue maturation. We also discuss how recent technological advances in single-cell and long-read methylome sequencing, along with targeted epigenome-editing, are enabling unprecedented high-resolution and mechanistic dissection of DNA methylome dynamics.

Rational design of N-doped CNTs@C3N4 network for dual-capture of biocatalysts in enzymatic glucose/O2 biofuel cells.

Carbonaceous materials are promising electrode materials for enzymatic biofuel cells (EBFCs) due to their excellent electrical conductivity, chemical and physical stability and biocompatibility. Design and preparation of carbon materials with a hollow structure and a rough surface are of great significance for immobilization of enzymes both inside and outside the carbon materials for EBFC applications. We report herein the synthesis of novel carbonaceous materials consisting of bamboo-shaped hollow N-doped carbon nanotubes (N-CNTs) and C3N4 nanosheets (denoted as N-CNTs@C3N4) as electrode materials for dual-capture of enzymes in glucose/O2 EBFCs. The combination of one-dimensional N-CNTs with an open structure and two-dimensional C3N4 nanosheets forms a three-dimensional crosslinking network that significantly enhances the immobilization of enzymes, electrode stability, and mass transfer of substrates, thus boosting the EBFC performance. As a result, EBFCs equipped with N-CNTs@C3N4 can generate a high open circuit potential of 0.93 V and output a maximum power density of 0.57 mW cm-2 at 0.47 V. Additionally, the as-fabricated glucose/O2 EBFCs are capable of directly harvesting energy from various soft drinks, which indicates the promising applications of the N-CNTs@C3N4 nanocomposite as an electrode material for EBFCs.

Confining Pyrrhotite Fe7 S8 in Carbon Nanotubes Covalently Bonded onto 3D Few-Layer Graphene Boosts Potassium-Ion Storage and Full-Cell Applications.

The pyrrhotite Fe7 S8 with mixed Fe-valence possesses high theoretical capacity, high conductivity, low discharge/charge voltage plateaus, and superior redox reversibility but suffers from structural degradation upon (de)potassiation process due to severe volume variations. Herein, to conquer this issue, a novel hierarchical architecture of confining nano-Fe7 S8 in carbon nanotubes covalently bonded onto 3D few-layer graphene (Fe7 S8 @CNT@3DFG) is designed for potassium storage. Notably, CNTs could successfully grow on the surface of 3DFG via a tip-growth model under the catalytic effect of Fe3 C. Such structure enables the hierarchical confinement of 0D nano-Fe7 S8 to 1D CNTs and further 1D CNTs to 3DFG, effectively buffering the volume variations, prohibiting the agglomeration of Fe7 S8 nanograins, and boosting the ionic/electronic transportation through the stable and conductive CNTs-grafted 3DFG framework. The as-prepared Fe7 S8 @CNT@3DFG electrode delivers an exceptional rate capability (502 mAh g-1 at 50 mA g-1 with 277 mAh g-1 at 1000 mA g-1 ) and an excellent long-term cyclic stability up to 1300 cycles. Besides, the in-situ XRD and ex-situ XPS/HRTEM results first elucidate the highly reversible potassium-storage mechanism of Fe7 S8 . Furthermore, the designed potassium full-cell employing Fe7 S8 @CNT@3DFG anode and potassium Prussian blue (KPB) cathode delivers a promising energy density of ≈120 Wh kg-1 , demonstrating great application prospects.

Iron Selenide Microcapsules as Universal Conversion-Typed Anodes for Alkali Metal-Ion Batteries.

Rechargeable alkali metal-ion batteries (AMIBs) are receiving significant attention owing to their high energy density and low weight. The performance of AMIBs is highly dependent on the electrode materials. It is, therefore, quite crucial to explore suitable electrode materials that can fulfil the future requirements of AMIBs. Herein, a hierarchical hybrid yolk-shell structure of carbon-coated iron selenide microcapsules (FeSe2 @C-3 MCs) is prepared via facile hydrothermal reaction, carbon-coating, HCl solution etching, and then selenization treatment. When used as the conversion-typed anode materials (CTAMs) for AMIBs, the yolk-shell FeSe2 @C-3 MCs show advantages. First, the interconnected external carbon shell improves the mechanical strength of electrodes and accelerates ionic migration and electron transmission. Second, the internal electroactive FeSe2 nanoparticles effectively decrease the extent of volume expansion and avoid pulverization when compared with micro-sized solid FeSe2 . Third, the yolk-shell structure provides sufficient inner void to ensure electrolyte infiltration and mobilize the surface and near-surface reactions of electroactive FeSe2 with alkali metal ions. Consequently, the designed yolk-shell FeSe2 @C-3 MCs demonstrate enhanced electrochemical performance in lithium-ion batteries, sodium-ion batteries, and potassium-ion batteries with high specific capacities, long cyclic stability, and outstanding rate capability, presenting potential application as universal anodes for AMIBs.

Blowing Iron Chalcogenides into Two-Dimensional Flaky Hybrids with Superior Cyclability and Rate Capability for Potassium-Ion Batteries.

Chalcogenide-based anodes are receiving increasing attention for rechargeable potassium-ion batteries (PIBs) due to their high theoretical capacities. However, they usually exhibit poor electrochemical performance due to poor structural stability, low conductivity, and severe electrolyte decomposition on the reactive surface. Herein, a method analogous to "blowing bubbles with gum" is used to confine FeS2 and FeSe2 in N-doped carbon for PIB anodes with ultrahigh cyclic stability and enhanced rate capability (over 5000 cycles at 2 A g-1). Several theoretical and experimental methods are employed to understand the electrodes' performance. The density functional theory calculations showed high affinity for potassium adsorption on the FeS2 and FeSe2. The in situ XRD and ex situ TEM analysis confirmed the formation of several intermediate phases of the general formula KxFeS2. These phases have high conductivity and large interlayer distance, which promote reversible potassium insertion and facilitate the charge transfer. Also, the calculated potassium diffusion coefficient during charge/discharge further proves the enhanced kinetics. Furthermore, The FeS2@NC anode in a full cell also exhibits high cyclic stability (88% capacity retention after 120 cycles with 99.9% Coulombic efficiency). Therefore, this work provides not only an approach to overcome several challenges in PIB anodes but also a comprehensive understanding of the mechanism and kinetics of the potassium interaction with chalcogenides.

Correction: Detecting rare diseases in electronic health records using machine learning and knowledge engineering: Case study of acute hepatic porphyria.

[This corrects the article DOI: 10.1371/journal.pone.0235574.].

Detecting rare diseases in electronic health records using machine learning and knowledge engineering: Case study of acute hepatic porphyria.

BACKGROUND: With the growing adoption of the electronic health record (EHR) worldwide over the last decade, new opportunities exist for leveraging EHR data for detection of rare diseases. Rare diseases are often not diagnosed or delayed in diagnosis by clinicians who encounter them infrequently. One such rare disease that may be amenable to EHR-based detection is acute hepatic porphyria (AHP). AHP consists of a family of rare, metabolic diseases characterized by potentially life-threatening acute attacks and chronic debilitating symptoms. The goal of this study was to apply machine learning and knowledge engineering to a large extract of EHR data to determine whether they could be effective in identifying patients not previously tested for AHP who should receive a proper diagnostic workup for AHP. METHODS AND FINDINGS: We used an extract of the complete EHR data of 200,000 patients from an academic medical center and enriched it with records from an additional 5,571 patients containing any mention of porphyria in the record. After manually reviewing the records of all 47 unique patients with the ICD-10-CM code E80.21 (Acute intermittent [hepatic] porphyria), we identified 30 patients who were positive cases for our machine learning models, with the rest of the patients used as negative cases. We parsed the record into features, which were scored by frequency of appearance and filtered using univariate feature analysis. We manually choose features not directly tied to provider attributes or suspicion of the patient having AHP. We trained on the full dataset, with the best cross-validation performance coming from support vector machine (SVM) algorithm using a radial basis function (RBF) kernel. The trained model was applied back to the full data set and patients were ranked by margin distance. The top 100 ranked negative cases were manually reviewed for symptom complexes similar to AHP, finding four patients where AHP diagnostic testing was likely indicated and 18 patients where AHP diagnostic testing was possibly indicated. From the top 100 ranked cases of patients with mention of porphyria in their record, we identified four patients for whom AHP diagnostic testing was possibly indicated and had not been previously performed. Based solely on the reported prevalence of AHP, we would have expected only 0.002 cases out of the 200 patients manually reviewed. CONCLUSIONS: The application of machine learning and knowledge engineering to EHR data may facilitate the diagnosis of rare diseases such as AHP. Further work will recommend clinical investigation to identified patients' clinicians, evaluate more patients, assess additional feature selection and machine learning algorithms, and apply this methodology to other rare diseases. This work provides strong evidence that population-level informatics can be applied to rare diseases, greatly improving our ability to identify undiagnosed patients, and in the future improve the care of these patients and our ability study these diseases. The next step is to learn how best to apply these EHR-based machine learning approaches to benefit individual patients with a clinical study that provides diagnostic testing and clinical follow up for those identified as possibly having undiagnosed AHP.

CoSe2/N-doped carbon porous nanoframe as an anode material for potassium-ion storage.

Transition metal selenides (TMS), on account of their relatively high theoretical capacity, unique electrical properties, easy compositing and low cost, are considered to be a candidate anode material for potassium-ion batteries. However, the cycling stability of TMS is unsatisfactory owing to the large intercalation/deintercalation of K ions. Herein, a CoSe2/N-doped carbon porous frame (CoSe2@NC) is successfully synthesized through a simple mixing and sintering approach and displays excellent potassium storage performance. Plentiful C-N bonds in the precursor can induce the formation of homogeneous N-doped carbon matrix and C-N-Co bonds, thus endowing robust structure and high electronic conductivity for superior cycling stability. Therefore, the unique porous nanoframe suppresses volume expansion and provides more diffusion paths for K ions. After 1000 cycles at 50 mA g-1, a high capacity of 311.3 mA h g-1 is acquired. When the current density increases to 500 mA g-1, the CoSe2@NC can still maintain a capacity of 184.5 mA h g-1 after 1000 cycles. The high performance, easy compositing and low cost of the CoSe2@NC make it a favorable material for application in KIBs.

Amorphous carbon coated SnO2 nanohseets on hard carbon hollow spheres to boost potassium storage with high surface capacitive contributions.

Potassium-ion batteries (KIBs) have becoming a prospective energy storage technique, due to the abundant potassium resources in the earth crust, approximate redox potential and similar electrochemical behavior of potassium and lithium. However, the insufficient capacity, poor stability and volume expansion of electrode materials during charge and discharge are main factors restricting the further development of KIBs. This work reports an amorphous carbon coated SnO2 nanohseets on hard carbon hollow spheres (AC/SnO2@HCHS) anode with enhanced potassium storage performance. The HCHS acts as a carrier for SnO2 nanosheets, providing high electrical conductivity and stable skeleton. The self-assembled SnO2 nanosheets with high surface area ensures sufficient contact with the electrolyte. Amorphous carbon wrapping can not only relieve SnO2 volume expansion but also provide surface-induced capacitive capacity. As a consequence, the AC/SnO2@HCHS anode presents excellent potassium-ion storage performance with high discharge capacity of 346 mAh g-1 at 0.1 A g-1 over 200 cycles, ultra-long cycling lifetime and outstanding rate capability (236 mAh g-1 at 1 A g-1 over 1000 cycles).

Flexible N doped carbon/bubble-like MoS2 core/sheath framework: Buffering volume expansion for potassium ion batteries.

Suitable anode materials for potassium ion batteries (KIBs) with high capacity, good reversibility and stable cycling performances are still in large demand. Here, flexible N doped carbon/bubble-like MoS2 core/sheath framework (MoS2/NCS) is prepared as an anode material for potassium ion batteries. The N doped carbon sponge (NCS) skeleton with good conductivity and high surface area guarantees superior rate capability and high stability of MoS2/NCS anode. The chemical bonds (CMo) firmly bridge MoS2 and NCS together, which further ensures MoS2/NCS stable cycling performance. More importantly, volume expansion is greatly buffered during cycling by this unique structure: the voids between bubble-like MoS2 sheath and NCS core can effectively buffer volume expansion generated during potassium intercalation/deintercalation; the enlarged interlayer spacing contribute more space to buffer volume change; the ultrathin nanosheets can shorten the charge diffusion distance and buffer volume change. As a consequence, MoS2/NCS delivers a capacity of 374 mAh g-1 over 200 cycles at 50 mA g-1. Even at 1000 mA g-1, a capacity of 212 mAh g-1 can still be obtained over 1000 cycles. We believe this MoS2/NCS structure will highlight the potential of MoS2 in practical KIBs applications.

Collaborative Design of Hollow Nanocubes, In Situ Cross-Linked Binder, and Amorphous Void@SiOx @C as a Three-Pronged Strategy for Ultrastable Lithium Storage.

Although silicon-based materials are ideal candidate anodes for high energy density lithium-ion batteries, the large volumetric expansion seriously damages the integrity of the electrodes and impedes commercial processes. Reasonable electrode design based on adjustable structures of silicon and strong binders prepared by a facile method is still a great challenge. Herein, a three-pronged collaborative strategy via hollow nanocubes, amorphous Void@SiOx @C, and in situ cross-linked polyacrylic acid and d-sorbitol 3D network binder (c-PAA-DS) is adopted to maintain structural/electrode integrality and stability. The all-integrated c-PAA-DS/Void@SiOx @C electrode delivers excellent mechanical property, which is attributed to ductility of the c-PAA-DS binder and high adhesion energy between Void@SiOx @C and c-PAA-DS calculated by density functional theory. Benefiting from the synergistic effect of accommodation of the hollow structure, protection of outer carbon shell, amorphous Void@SiOx @C, and strong adhesive c-PAA-DS binder, c-PAA-DS/Void@SiOx @C shows excellent electrochemical performance. Long cycling stability with a reversible capacity of 696 mAh g-1 is obtained, as well as tiny capacity decay after 500 cycles at 0.5 A g-1 and high-rate performance. The prelithiated Void@SiOx @C||LiNi0.5 Co0.2 Mn0.3 O2 (NCM523) full cell is also assembled and shows a reversible capacity of 157 mAh g-1 at 0.5 C, delivering an excellent capacity retention of 94% after 160 cycles.

Hollow Multihole Carbon Bowls: A Stress-Release Structure Design for High-Stability and High-Volumetric-Capacity Potassium-Ion Batteries.

Potassium-ion batteries are potential alternatives to lithium-ion batteries for large-scale energy storage considering the low cost and high abundance of potassium. However, it is challenging to obtain stable electrode materials capable of undergoing long-term potassiation/depotassiation due to the high accumulated stress associated with the huge volume variation of the electrode. Here, we simulate the von Mises stress distributions of four different carbon three-dimensional models under an isotropic initial stress by the finite element method and reveal the critical role of the structure of a hollow multihole bowl on the strain-relaxation behavior. In this regard, nitrogen/oxygen codoped carbon hollow multihole bowls (CHMBs) are synthesized via hydrothermal carbonization coupled with an emulsion-templating strategy using biomass as the carbon source. Consistent with our simulation results, the CHMB anode remains stable for over 1000 cycles and delivers a high reversible capacity of 304 mAh g-1 at 0.1 A g-1. In addition to the reduced stress accumulation, the good electrochemical performances are also attributed to the surface capacitive mechanism and the shortened electron/ion transport distance in CHMBs. In particular, the CHMB composite electrode has a volumetric specific capacity 56% higher than that of hollow spheres due to the high tapped density of the bowl-shaped particles.

High-Throughput Production of Zr-Doped Li4 Ti5 O12 Modified by Mesoporous Libaf3 Nanoparticles for Superior Lithium and Potassium Storage.

Li4 Ti5 O12 is a promising anode for lithium-ion batteries due to its zero-strain properties. However, its low conductivity has greatly affected its rate performance. At the same time, the electrolyte decomposition during cycling also needs to be solved, especially at low cut-off voltage. Herein, using a high-throughput two-step method, we synthesized Zr-doped LTO modified by mesoporous LiBaF3 nanoparticles for alkali-ion storage. The doping of Zr can enhance the electronic conductivity and facilitate the rate performance. Meanwhile, the coating of mesoporous LiBaF3 nanoparticles can form a mesoporous surface with large pore size (ca. 3-10 nm), which can benefit the alkali ion diffusion and simultaneously restrain the formation of an excess solid electrolyte interface to a reasonable range. The optimized material is used as an advanced anode for both lithium-ion and potassium-ion batteries, and good battery behavior including high-rate performance and high stability is achieved.

Deeply Nesting Zinc Sulfide Dendrites in Tertiary Hierarchical Structure for Potassium Ion Batteries: Enhanced Conductivity from Interior to Exterior.

Transition metal sulfides are deemed as attractive anode materials for potassium-ion batteries (KIBs) due to their high theoretical capacities based on conversion and alloying reaction. However, the main challenges are the low electronic conductivity, huge volume expansion, and consequent formation of unstable solid electrolyte interphase (SEI) upon potassiation/depotassiation. Herein, zinc sulfide dendrites deeply nested in the tertiary hierarchical structure through a solvothermal-pyrolysis process are designed as an anode material for KIBs. The tertiary hierarchical structure is composed of the primary ultrafine ZnS nanorods, the secondary carbon nanosphere, and the tertiary carbon-encapsulated ZnS subunits nanosphere structure. The architectural design of this material provides a stable diffusion path and enhances effective conductivity from the interior to exterior for both K+ ions and electrons, buffers the volume expansion, and constructs a stable SEI during cycling. A stable specific capacity of 330 mAh g-1 is achieved after 100 cycles at the current density of 50 mA g-1 and 208 mAh g-1 at 500 mA g-1 over 300 cycles. Using density functional theory calculations, we discover the interactions between ZnS and carbon interface can effectively decrease the K+ ions diffusion barrier and therefore promote the reversibility of K+ ions storage.

A new dual-ion battery based on amorphous carbon.

The Na-based dual-ion batteries (NDIBs), combining the advantages of Na-ion batteries and dual-ion batteries, are attracting more attention due to their merits of abundant source, low cost and high energy density. However, the main challenges faced by NDIBs are their low capacity and poor cycling. Herein, we report a new ion storage mechanism for high-performance NDIBs using amorphous carbon (AOMC) as cathode. Unlike the graphite carbon that can only accommodate the PF6- anion (typical DIB system), the AOMC herein can both accommodate Na+ cation and PF6- anion due to its amorphous feature, which is conceptually new dual-ion system for achieving much higher capacity. Ex-situ X-ray photoelectron spectroscopy, X-ray diffraction and Raman studies reveal that the disordered carbon in the AOMC can be transformed to the partial graphitic stacking in short range, improving both capacity and cycling stability of NDIBs. As a consequence, the AOMC delivers a highly reversible storage capacity of 136 mAh g-1 for 800 cycles at a very high current density of 2.0 A g-1, much higher than all the reported NDIBs. Such concept can be generalized to develop high-performance dual-ion full cell using sodium ion pre-intercalated materials as anode and AOMC as cathode.

Metallic Octahedral CoSe2 Threaded by N-Doped Carbon Nanotubes: A Flexible Framework for High-Performance Potassium-Ion Batteries.

Due to the abundant and low-cost K resources, the exploration of suitable materials for potassium-ion batteries (KIBs) is advancing as a promising alternative to lithium-ion batteries. However, the large-sized and sluggish-kinetic K ions cause poor battery behavior. This work reports a metallic octahedral CoSe2 threaded by N-doped carbon nanotubes as a flexible framework for a high-performance KIBs anode. The metallic property of CoSe2 together with the highly conductive N-doped carbon nanotubes greatly accelerates the electron transfer and improves the rate performance. The carbon nanotube framework serves as a backbone to inhibit the agglomeration, anchor the active materials, and stabilize the integral structure. Every octahedral CoSe2 particle arranges along the carbon nanotubes in sequence, and the zigzag void space can accommodate the volume expansion during cycling, therefore boosting the cycling stability. Density functional theory is also employed to study the K-ion intercalation/deintercalation process. This unique structure delivers a high capacity (253 mAh g-1 at 0.2 A g-1 over 100 cycles) and enhanced rate performance (173 mAh g-1 at 2.0 A g-1 over 600 cycles) as an advanced anode material for KIBs.