Oxygen Defect Engineering toward Zero-Strain V2O2.8@Porous Reticular Carbon for Ultrastable Potassium Storage.

Potassium-ion batteries (KIBs) are promising candidates for large-scale energy storage devices due to their high energy density and low cost. However, the large potassium-ion radius leads to its sluggish diffusion kinetics during intercalation into the lattice of the electrode material, resulting in electrode pulverization and poor cycle stability. Herein, vanadium trioxide anodes with different oxygen vacancy concentrations (V2O2.9, V2O2.8, and V2O2.7 determined by the neutron diffraction) are developed for KIBs. The V2O2.8 anode is optimal and exhibits excellent potassium storage performance due to the realization of expanded interlayer spacing and efficient ion/electron transport. In situ X-ray diffraction indicates that V2O2.8 is a zero-strain anode with a volumetric strain of 0.28% during the charge/discharge process. Density functional theory calculations show that the impacts of oxygen defects are embodied in reducing the band gap, increasing electron transfer ability, and lowering the diffusion energy barriers for potassium ions. As a result, the electrode of nanosized V2O2.8 embedded in porous reticular carbon (V2O2.8@PRC) delivers high reversible capacity (362 mAh g-1 at 0.05 A g-1), ultralong cycling stability (98.8% capacity retention after 3000 cycles at 2 A g-1), and superior pouch-type full-cell performance (221 mAh g-1 at 0.05 A g-1). This work presents an oxygen defect engineering strategy for ultrastable KIBs.

[Application of copy number variation sequencing in patients with intellectual disability/developmental delay and autistic spectrum disorder].

OBJECTIVE: To assess the value of copy number variation sequencing (CNV-seq) for the diagnosis of children with intellectual disability (ID), developmental delay (DD), and autistic spectrum disorder (ASD). METHODS: Forty patients with ID/DD/ASD referred to Nanshan Maternity and Child Health Care Hospital from September 2018 to January 2022 were enrolled. G-banded karyotyping analysis was carried out for the patients. Genomic DNA was extracted from peripheral blood samples and subjected to CNV-Seq analysis to detect chromosome copy number variations (CNVs) in such patients. ClinVar, DECIPHER, OMIM and other database were searched for data annotation. RESULTS: Among the 40 patients (including 30 males and 10 females), 16, 15 and 6 were diagnosed with ID, DD and ASD, respectively. One patient had combined symptoms of ID and DD, whilst the remaining two had combined ID and ASD. Four patients were found with abnormal karyotypes, including 47,XY,+mar, 46,XY,inv(8)(p11.2q21.2), 46,XX,del(5)(p14) and 46,XX[76]/46,X,dup(X)(p21.1q12). Chromosome polymorphism was also found in two other patients. CNV-seq analysis has detected 32 CNVs in 20 patients (50.0%, 20/40). Pathogenic CNVs were found in 10 patients (25.0%), 15 CNVs of uncertain clinical significance were found in 12 patients (30.0%), and 7 likely benign CNVs were found in 4 patients (10.0%). CONCLUSION: Chromosome CNVs play an important role in the pathogenesis of ID/DD/ASD. CNV-seq can detect chromosomal abnormalities including microdeletions and microduplications, which could provide a powerful tool for revealing the genetic etiology of ID/DD/ASD patients.

Predictive value of the second-trimester fibronectin concentration for severe preeclampsia: A prospective nested case-control study in China.

AIM: To evaluate the value of the second-trimester fibronectin concentration, alone and in combination with other markers (e.g., mean arterial pressure, inhibin A), in the identification of women who subsequently develop severe preeclampsia. METHODS: For this prospective nested case-control study, serum from pregnant women (gestational age 15-22 weeks) who underwent routine Down syndrome screening was analyzed. The women were tracked to delivery and assigned to the severe preeclampsia or control group, according to whether they developed severe preeclampsia. Each woman who later developed severe preeclampsia was paired with five healthy women with pregnancies of similar gestational age (± 1 week). Fibronectin, inhibin A, human chorionic gonadotropin, placental growth factor, cysteine, and homocysteine concentrations were measured in 44 cases in the severe preeclampsia group and 220 cases in the control group. The body mass index and mean arterial pressure were calculated. All results were compared between the two groups. Logistic regression analysis and receiver operating characteristic curve construction were conducted for markers differing significantly between two groups. RESULTS: The second-trimester fibronectin value was positively correlated with severe preeclampsia and predicted 67.7% of severe preeclampsia cases. The combination of fibronectin, inhibin A, and mean arterial pressure predicted 76.7% of severe preeclampsia cases; predictive values for combinations of fibronectin with mean arterial pressure or inhibin A were 75.4% and 74.6%, respectively. Combination with these other markers increased the predictive value of fibronectin. In addition, fibronectin was more powerful for the late severe preeclampsia and severe preeclampsia without fetal growth restriction subgroups. CONCLUSIONS: The second-trimester fibronectin concentration can be used to predict severe preeclampsia.

Carbon Nanofibers Propped Hierarchical Porous SiOC Ceramics Toward Efficient Microwave Absorption.

The hierarchical porous SiOC ceramics (HPSCs) have been prepared by the pyrolysis of precursors (the mixture of dimethicone and KH-570) and polyacrylonitrile nanofibers (porous template). The HPSCs possess hierarchical porous structure with a BET surface area of 51.4 m2/g and have a good anti-oxidation property (only 5.1 wt.% weight loss). Owing to the porous structure, the HPSCs deliver an optimal reflection loss value of - 47.9 dB at 12.24 GHz and an effective absorption bandwidth of 4.56 GHz with a thickness of 2.3 mm. The amorphous SiOC, SiOx, and free carbon components within SiOC make contributions to enhancing dipolar polarization. Besides, the abundant interfaces between SiOC and carbon nanofibers (CNFs) are favorable for improving interfacial polarization. The conductive loss arisen from cross-linked CNFs can also boost the microwave absorption performance.

Sodium/Potassium-Ion Batteries: Boosting the Rate Capability and Cycle Life by Combining Morphology, Defect and Structure Engineering.

Carbon-based materials have been considered as the most promising anode materials for both sodium-ion batteries (SIBs) and potassium-ion batteries (PIBs), owing to their good chemical stability, high electrical conductivity, and environmental benignity. However, due to the large sizes of sodium and potassium ions, it is a great challenge to realize a carbon anode with high reversible capacity, long cycle life, and high rate capability. Herein, by rational design, N-doped 3D mesoporous carbon nanosheets (N-CNS) are successfully synthesized, which can realize unprecedented electrochemical performance for both SIBs and PIBs. The N-CNS possess an ultrathin nanosheet structure with hierarchical pores, ultrahigh level of pyridinic N/pyrrolic N, and an expanded interlayer distance. The beneficial features that can enhance the Na-/K-ion intercalation/deintercalation kinetic process, shorten the diffusion length for both ions and electrons, and accommodate the volume change are demonstrated. Hence, the N-CNS-based electrode delivers a high capacity of 239 mAh g-1 at 5 A g-1 after 10 000 cycles for SIBs and 321 mAh g-1 at 5 A g-1 after 5000 cycles for PIBs. First-principles calculation shows that the ultrahigh doping level of pyridinic N/pyrrolic N contributes to the enhanced sodium and potassium storage performance by modulating the charge density distribution on the carbon surface.

A Dual-Functional Conductive Framework Embedded with TiN-VN Heterostructures for Highly Efficient Polysulfide and Lithium Regulation toward Stable Li-S Full Batteries.

Lithium-sulfur (Li-S) batteries are strongly considered as next-generation energy storage systems because of their high energy density. However, the shuttling of lithium polysulfides (LiPS), sluggish reaction kinetics, and uncontrollable Li-dendrite growth severely degrade the electrochemical performance of Li-S batteries. Herein, a dual-functional flexible free-standing carbon nanofiber conductive framework in situ embedded with TiN-VN heterostructures (TiN-VN@CNFs) as an advanced host simultaneously for both the sulfur cathode (S/TiN-VN@CNFs) and the lithium anode (Li/TiN-VN@CNFs) is designed. As cathode host, the TiN-VN@CNFs can offer synergistic function of physical confinement, chemical anchoring, and superb electrocatalysis of LiPS redox reactions. Meanwhile, the well-designed host with excellent lithiophilic feature can realize homogeneous lithium deposition for suppressing dendrite growth. Combined with these merits, the full battery (denoted as S/TiN-VN@CNFs || Li/TiN-VN@CNFs) exhibits remarkable electrochemical properties including high reversible capacity of 1110 mAh g-1 after 100 cycles at 0.2 C and ultralong cycle life over 600 cycles at 2 C. Even with a high sulfur loading of 5.6 mg cm-2 , the full cell can achieve a high areal capacity of 5.5 mAh cm-2 at 0.1 C. This work paves a new design from theoretical and experimental aspects for fabricating high-energy-density flexible Li-S full batteries.

Early prediction of preeclampsia and small-for-gestational-age via multi-marker model in Chinese pregnancies: a prospective screening study.

BACKGROUND: Recent evidence suggests early screening of preeclampsia and small-for-gestational-age (SGA) would benefit pregnancies followed by subsequent prophylactic use of aspirin. Multi-marker models have shown capability of predicting preeclampsia and SGA in first trimester. Yet the clinical feasibility of combined screening model for Chinese pregnancies has not been fully assessed. The aim of this study is to evaluate the applicability of a multi-marker screening model to the prediction of preeclampsia and SGA in first trimester particularly among Chinese population. METHODS: Three thousand two hundred seventy pregnancies meeting the inclusion criteria took first-trimester screening of preeclampsia and SGA. A prior risk based on maternal characteristics was evaluated, and a posterior risk was assessed by combining prior risk with multiple of median (MoM) values of mean arterial pressure (MAP), serum placental growth factor (PLGF) and pregnancy associated plasma protein A (PAPP-A). Both risks were calculated by Preeclampsia PREDICTOR™ software, Perkin Elmer. Screening performance of prior and posterior risks for early and late preeclampsia by using PREDICTOR software was shown by Receiver Operating Characteristics (ROC) curves. The estimation of detection rates and false positive rates of delivery with both preeclampsia and SGA was made. RESULTS: Eight cases developed early preeclampsia (0.24%) and 35 were diagnosed as late preeclampsia (1.07%). Five with early preeclampsia and ten with late preeclampsia later delivered SGA newborns (0.46%); 84 without preeclampsia gave birth to the SGAs (2.57%). According to ROC curves, posterior risks performed better than prior risks in terms of preeclampsia, especially in early preeclampsia. At 10% false positive rate, detection rates of early and late preeclampsia were 87.50 and 48.57%, detection rates of early and late SGA were 41.67 and 28.00%, respectively. For SGA, detection rates in cases with preeclampsia were much higher than those in absence of it. CONCLUSIONS: This study demonstrates that combined screening model could be useful for predicting early preeclampsia in Chinese pregnancies. Furthermore, the performance of SGA screening by same protocol is strongly associated with preeclampsia.

Three-Dimensional Ordered Macroporous Metal-Organic Framework Single Crystal-Derived Nitrogen-Doped Hierarchical Porous Carbon for High-Performance Potassium-Ion Batteries.

The biggest challenge of potassium-ion batteries (KIBs) application is to develop high-performance electrode materials to accommodate the potassium ions large size. Herein, by rational design, we carbonize three-dimensional (3D) ordered macroporous ZIF-8 to fabricate 3D interconnected nitrogen-doped hierarchical porous carbon (N-HPC) that shows excellent rate performance (94 mAh g-1 at 10.0 A g-1), unprecedented cycle stability (157 mA g-1 after 12000 cycles at 2.0 A g-1), and superior reversible capacity (292 mAh g-1 at 0.1 A g-1). The 3D hierarchical porous structure diminishes the diffusion distance for both ions/electrons, while N-doping improves the reactivity and electronic conductivity via producing more defects. In addition, the bicontinuous structure possesses a large specific surface area, decreasing the current density, again improving the rate performance. In situ Raman spectra analysis confirms the potassiation and depotassiation in the N-HPC are highly reversible processes. The galvanostatic intermittent titration measurement and first-principles calculations reveal that the interconnected macropores are more beneficial to the diffusion of the K+. This 3D interpenetrating structure demonstrates a superiority for energy storage applications.

Encapsulation of SeS2 into Nitrogen-Doped Free-Standing Carbon Nanofiber Film Enabling Long Cycle Life and High Energy Density K-SeS2 Battery.

K-SeS2 batteries could provide a low-cost and high energy density energy storage system, because the earth-abundant element potassium (K) shows a low reduction potential and a high gravimetric capacity. But the K-SeS2 battery has never been reported because of the lack of high-performance electrode materials. Herein, we design an advanced K-SeS2 battery by encapsulation of SeS2 in the nitrogen-doped free-standing porous carbon matrix (SeS2@NCNFs). The self-supported SeS2@NCNFs electrode achieves a high reversible capacity of 417 mAh g-1 after 1000 cycles with 85% capacity retention at 0.5 Ag1- with nearly 100% Coulombic efficiency. The nanosized SeS2 nanoparticles are encapsulated in the carbon matrix, which minimizes the volume expansion during cycling and shortens the ion transport pathways, thus enhancing the rate capability. The interconnected porous carbon nanofiber structure could improve the flexibility and offer a continuous pathway for rapid ionic/electronic transport. The DFT calculations confirm that high content N-doping (11.2 at. %) can enhance the chemical affinity between the discharge product and the N-doped carbon. The pyrrolic and pyridinic N-doping lead to stronger adsorption than that of the graphitic N-doping. This proposed design holds great promise for practical application of high energy density K-SeS2 batteries.

Mxenes Derived Laminated and Magnetic Composites with Excellent Microwave Absorbing Performance.

Two dimensional materials have been widely identified as promising microwave absorbers, owing to their large surface area and abundant interfaces. Here, a novel laminated and magnetic composite derived from Mxene was designed and successfully synthesized via facile hydrothermal oxidization of nickel ion intercalated Ti3C2. Highly disordered carbon sheets were obtained by low temperature hydrothermal oxidization, and the in-situ produced TiO2 and NiO nanoparticles embedded closely between them. This layered hybrid exhibits excellent microwave absorbing performance with an effective absorbing bandwidth as high as 11.1 GHz (6.9-18 GHz) and 9 GHz (9-18 GHz) when the thickness is 3 and 2 mm, respectively. Besides the high dielectric loss, magnetic loss and ohmic loss of the composite, the amorphous nature of obtained carbon sheets and multi-reflections between them are believed to play a decisive role in achieving such superior microwave absorbing performance.

Dual-functional SiOC ceramics coating modified carbon fibers with enhanced microwave absorption performance.

Multi-functional carbon fiber (CF) based composites have great potential as new-type microwave absorption materials (MAMs). However, it was still a huge challenge to integrate antioxidation and MA properties into CF based composites. Herein, the SiOC ceramics coating modified carbon fibers (SiOC/CFs) were prepared by a polymer precursor pyrolysis method. The X-ray photoelectron spectroscopy (XPS) revealed that the SiOC coating was composed of SiOC, SiO2, and amorphous carbon phases. The SiOC ceramics as dual-functional coating not only heightened the oxidation temperature from 415 °C to 890 °C, but also highly improved the microwave absorbing ability from -12.60 dB to -47.50 dB. The enhanced MA performance could be attributed to multiple reflections in the cross-linked structure, various polarization relaxation processes, and the favorable impedance matching effect. The SiOC ceramics coating as a semiconductor could suppress the skin effect originating from the cross-linked CF network, thus leading to a favorable impedance matching behavior.

Regulating Lithium Nucleation via CNTs Modifying Carbon Cloth Film for Stable Li Metal Anode.

Li metal is demonstrated as one of the most promising anode materials for high energy density batteries. However, uncontrollable Li dendrite growth and repeated growth of solid electrolyte interface during the charge/discharge process lead to safety issues and capacity decay, preventing its practical application. To address these issues, an effective strategy is to realize uniform Li nucleation. Here, a stable lithium-scaffold composite electrode (CC/CNT@Li) is designed by melting of lithium metal into 3D interconnected lithiophilic carbon nanotube (CNT) on a porous carbon cloth (CC). The 3D interconnected CNTs successfully change the lithiophobic CC into lithiophilic nature, reducing the polarization of the electrode, ensuring homogenous Li nucleation and continuous smooth Li plating. The CNTs on the surface of CC provide adequate Li nucleation sites and reduce the areal current density to avoid Li dendrite growth. The 3D porous structure of CC/CNT offers enough free room for buffering the huge volume change during Li plating/stripping. The CC/CNT@Li composite anode exhibits dendrite-free morphology and superior cycling performances over 500 h with low voltage hysteresis of 18, 23, and 71 mV at the current density of 1, 2, and 5 mA cm-2 , respectively.

CNT Interwoven Nitrogen and Oxygen Dual-Doped Porous Carbon Nanosheets as Free-Standing Electrodes for High-Performance Na-Se and K-Se Flexible Batteries.

Na-Se and K-Se batteries are attractive as a stationary energy storage system because of much abundant resources of Na and K in the Earth's crust. As the alloy-type Se has a severe pulverization issue, one critical challenge to develop advanced Na-Se and K-Se batteries is to explore a highly efficient and stable Se-based cathode. Herein, a flexible free-standing Se/carbon composite film is prepared by encapsulation of Se into a carbon nanotube (CNT) interwoven N,O dual-doped porous carbon nanosheet (Se@NOPC-CNT). The 3D interconnected CNT uniformly wrapped on the N,O dual-doped porous carbon skeletons improves the flexibility and offers an interconnected conductive pathway for rapid ionic/electronic transport. In addition, the N,O dual-doping significantly enhances the chemical affinity and adhesion between Nax Se/Kx Se (0 < x ≤ 2) and porous carbon, which is confirmed by density functional theory calculation. When used as the cathode in Na-Se batteries, the Se@NOPC-CNT delivers a remarkable reversible capacity of 400 mA h g-1 at 1 A g-1 after 2000 cycles with a 0.008% capacity decay per cycle. For K-Se batteries, it also exhibits an excellent cycling stability (335 mA h g-1 after 700 cycles at 0.8 A g-1 ). This unique design may open an avenue for practical application of flexible Na-Se and K-Se batteries.

Carbon and Carbon Hybrid Materials as Anodes for Sodium-Ion Batteries.

Sodium-ion batteries (SIBs) have attracted much attention for application in large-scale grid energy storage owing to the abundance and low cost of sodium sources. However, low energy density and poor cycling life hinder practical application of SIBs. Recently, substantial efforts have been made to develop electrode materials to push forward large-scale practical applications. Carbon materials can be directly used as anode materials, and they show excellent sodium storage performance. Additionally, designing and constructing carbon hybrid materials is an effective strategy to obtain high-performance anodes for SIBs. In this review, we summarize recent research progress on carbon and carbon hybrid materials as anodes for SIBs. Nanostructural design to enhance the sodium storage performance of anode materials is discussed, and we offer some insight into the potential directions of and future high-performance anode materials for SIBs.

Ti3C2 MXene: a promising microwave absorbing material.

In this work, we demonstrate the enhancement of microwave attenuation capability of Ti3C2 enabled microwave absorbing materials (MAMs) within a frequency range of 2-18 GHz. Ti3C2 nano-sheet/paraffin composites exhibit enhanced microwave absorbing performance with an effective absorbing bandwidth of 6.8 GHz (11.2-18 GHz) at 2 mm and an optimal reflection loss of -40 dB at 7.8 GHz. Moreover, mechanisms for the dielectric responses of the Ti3C2 MXene nanosheets are intensively discussed. Three typical electric polarizations of Ti3C2 are illustrated with the Cole-Cole diagram. The enhanced microwave absorbing properties can be ascribed to the high dielectric loss accompanied with the strong multi-reflections between MXene layers.