The cathode materials for sodium‐sulfur batteries have attracted great attention since cathode is one of the important components of the sodium‐sulfur battery, and there are cathode materials that ...have high capacity, non‐toxicity, and cost‐efficiency. Nevertheless, due to their low Coulombic efficiency and proneness to cycling decay, the practical application of the sodium–sulfur battery has always been suppressed. In terms of the responsibility of these problems, the polysulfide shuttle and the sluggish kinetics are the main culprits. To address these issues, impeding the notorious reaction between polysulfide intermediates on the cathode and improve the kinetics reaction on the anode are extremely important. Herein, a comprehensive review is prepared of different approaches to increasing the electrochemical performance and strengthening the stability of cathodes. The influences of various choices and the consequent properties of the cathode in relation to the whole sodium–sulfur battery performance is investigated. Finally, the current research challenges related to cathodes for sodium–sulfur batteries and future perspectives are also discussed.
The shuttle effect and sluggish kinetics are critical challenges for the sulfur cathodes of room temperature sodium‐sulfur (RT Na‐S) batteries. To achieve excellent performance, many strategies have been implemented to address these challenges. In this review, the recent developments on sulfur cathodes is summarized and divide them into five types. Perspectives on sulfur cathodes for RT Na‐S batteries are provided for future improvements.
Vacancies created on a surface can alter the local electronic structure, thus enabling a higher intrinsic activity for the evolution of hydrogen and oxygen. Conventional strategies for vacancy ...engineering, however, have a strong focus on non‐metal sulfur/oxygen defects, which have often overlooked metallic vacancies. Herein, evidence is provided that cobalt vacancies can be atomically tuned to have different sizes to achieve cobalt vacancy clusters through controlling the migration of iridium single atoms. The coalescence of Co vacancy clusters at the surface of an IrCo alloy results in an increased d‐band level and eventually compromises H adsorption, leading to enhanced electrocatalytic activity toward the hydrogen evolution reaction. In addition, the Co vacancy clusters can improve the electronic conductivity with respect to the oxidized Co surface, which substantially aids in strengthening the adsorption of oxygen intermediates toward an effective oxygen evolution reaction at a low overpotential. These collective effects originate from the Co vacancy cluster and specifically enable highly efficient and stable water splitting with a low total overpotential of 384 mV in alkaline media and 365 mV in an acidic environment, achieving a current density of 10 mA cm–2.
Cobalt vacancy‐cluster can address technological challenges of splitting water to simultaneously enable water oxidation and reduction reactions via optimized electronic structures, leading to efficient water electrolysis at low overpotential. In addition, evidence is provided that the cobalt vacancies can be atomically tuned to have different sizes to achieve cobalt vacancy clusters through controlling the migration of iridium single atoms.
It is vital to dynamically regulate S activity to achieve efficient and stable room‐temperature sodium–sulfur (RT/Na−S) batteries. Herein, we report using cobalt sulfide as an electron reservoir to ...enhance the activity of sulfur cathodes, and simultaneously combining with cobalt single atoms as double‐end binding sites for a stable S conversion process. The rationally constructed CoS2 electron reservoir enables the straight reduction of S to short‐chain sodium polysulfides (Na2S4) via a streamlined redox path through electron transfer. Meanwhile, cobalt single atoms synergistically work with the electron reservoir to reinforce the streamlined redox path, which immobilize in situ formed long‐chain products and catalyze their conversion, thus realizing high S utilization and sustainable cycling stability. The as‐developed sulfur cathodes exhibit a superior rate performance of 443 mAh g−1 at 5 A g−1 with a high cycling capacity retention of 80 % after 5000 cycles at 5 A g−1.
Engineering CoS2 as electron reservoirs overcomes the limited length of the electron diffusion tunnel over an insulating sulfur cathode and thus achieves fast reaction kinetics in sodium–sulfur batteries. With the assistance of Co1 single atoms, this strategy provides streamlined redox paths, which reduce the formation of unstable polysulfides and enable stable sodium–sulfur batteries.
Summary
The Orchidaceae is of economic and ecological importance and constitutes ˜10% of all seed plant species. Here, we report a genome physical map for Cymbidium sinense, a well‐known species ...belonging to genus Cymbidium that has thousands of natural variation varieties of flower organs, flower and leaf colours and also referred as the King of Fragrance, which make it arose into a unique cultural symbol in China. The high‐quality chromosome‐scale genome assembly was 3.52 Gb in size, 29 638 protein‐coding genes were predicted, and evidence for whole‐genome duplication shared with other orchids was provided. Marked amplification of cytochrome‐ and photosystem‐related genes was observed, which was consistent with the shade tolerance and dark green leaves of C. sinense. Extensive duplication of MADS‐box genes, and the resulting subfunctional and expressional differentiation, was associated with regulation of species‐specific flower traits, including wild‐type and mutant‐type floral patterning, seasonal flowering and ecological adaption. CsSEP4 was originally found to positively regulate gynostemium development. The CsSVP genes and their interaction proteins CsAP1 and CsSOC1 were significantly expanded and involved in the regulation of low‐temperature‐dependent flowering. Important genetic clues to the colourful leaf traits, purple‐black flowers and volatile trait in C. sinense were also found. The results provide new insights into the molecular mechanisms of important phenotypic traits of Cymbidium and its evolution and serve as a powerful platform for future evolutionary studies and molecular breeding of orchids.
The determination of impact sensitivity of energetic materials traditionally relies on expensive and safety-challenged experimental means. This has instigated a shift towards scientific computations ...to gain insights into and predict the impact response of energetic materials. In this study, we refine the phonon-vibron coupling coefficients
ζ
in energetic materials subjected to impact loading, building upon the foundation of the phonon up-pumping model. Considering the full range of interactions between high-order phonon overtones and molecular vibrational frequencies, this is a pivotal element for accurately determining phonon-vibron coupling coefficients
ζ
. This new coupling coefficient
ζ
relies exclusively on phonon and molecular vibrational frequencies within the range of 0-700 cm
−1
. Following a regression analysis involving
ζ
and impact sensitivity (
H
50
) of 45 molecular nitroexplosives, we reassessed the numerical values of damping factors, establishing
a
= 2.5 and
b
= 35. This coefficient is found to be a secondary factor in determining sensitivity, secondary to the rate of decomposition propagation and thermodynamic factor (heat of explosion). Furthermore, the relationship between phonon-vibron coupling coefficients
ζ
and impact sensitivity was studied in 16 energetic crystalline materials and eight nitrogen-rich energetic salts. It was observed that as the phonon-vibron coupling coefficient increases, the tendency for reduced impact sensitivity
H
50
still exists.
The impact of the damping factor a and b on phonon-vibron coupling strength.
In current work, air impingement drying (AID), infrared-assisted hot air-drying (IR-HAD), and hot air drying based on temperature and humidity control (TH-HAD) drying technologies were employed to ...drying potato cubes and their effects on drying kinetics, color, ascorbic acid content, rehydration ratio, microstructure, and specific energy consumption (SEC) were explored. Besides, artificial neural network (ANN) was used to predict changes in moisture ratio during the drying process. Results indicated that TH-HAD had the shortest drying time, followed by IR-HAD and AID. The effective moisture diffusivity (D
eff
) of potato under TH-HAD, IR-HAD and AID were 1.35 × 10
−9
, 1.18 × 10
−9
, and 0.90 × 10
−9
m
2
/s, respectively. TH-HAD contributed to excellent physicochemical properties of dried potato when compared to samples dried by IR-HAD and AID. Overall, TH-HAD provided higher ascorbic acid content, better rehydration ability, brighter color, and had lower specific energy consumption (SEC). The microstructure well explained the difference of rehydration ratio and drying kinetics under different drying methods. The ANN models with the optimal topology could predict the moisture ratio under different drying methods with satisfactory accuracy. The current findings indicate that TH-HAD is a promising drying technology for potato cubes and has the potential to be applied in commercial scale.
Background
Laparoscopic major hepatectomy (LMH) for hepatocellular carcinoma (HCC) in patients with cirrhosis remains controversial due to limited reports in the literature. This study analyzed the ...perioperative and oncological outcomes of LMH for HCC with cirrhosis compared with open major hepatectomy (OMH).
Methods
A retrospective analysis of patients with cirrhosis who underwent major hepatectomy for HCC between January 2015 and January 2017 was performed. Patients were divided into the LMH group and the OMH group. Short-term and oncological outcomes were compared before and after 1:1 propensity score matching (PSM).
Results
A total of 103 HCC patients who received major liver resection were enrolled. There were 36 (35.0%) patients in the LMH group and 67 (65.0%) patients in the OMH group. After 1:1 PSM, well-matched 32 patients in each group were evaluated. Significant differences were observed in operative time (median, 255 vs. 200 min,
p
< 0.001) and Pringle time (median, 50 vs. 30 min,
p
< 0.001) between two groups. The blood loss and transfusion requirement were comparable in two groups. The rate of overall postoperative complications did not differ between two groups, while the incidence of ascites in the LMH group was significantly less than OMH group (9.4 vs. 31.3%,
p
= 0.030). The oncological outcomes between the two groups were comparable with regard to 2-year overall survival (85.7 vs. 86.7%,
p
= 0.694) and disease-free survival (72.9 vs. 81.5%,
p
= 0.990), respectively.
Conclusions
LMH for HCC patients with liver cirrhosis showed comparable results in terms of postoperative morbidity and oncological outcomes compared with traditional open procedure. LMH may serve as a safe and feasible alternative for selected HCC patients with cirrhosis.
Mice are widely used as experimental models for gut microbiome (GM) studies, yet the majority of mouse GM members remain uncharacterized. Here, we report the construction of a mouse gut microbial ...biobank (mGMB) that contains 126 species, represented by 244 strains that have been deposited in the China General Microorganism Culture Collection. We sequence and phenotypically characterize 77 potential new species and propose their nomenclatures. The mGMB includes 22 and 17 species that are significantly enriched in ob/ob and wild-type C57BL/6J mouse cecal samples, respectively. The genomes of the 126 species in the mGMB cover 52% of the metagenomic nonredundant gene catalog (sequence identity ≥ 60%) and represent 93-95% of the KEGG-Orthology-annotated functions of the sampled mouse GMs. The microbial and genome data assembled in the mGMB enlarges the taxonomic characterization of mouse GMs and represents a useful resource for studies of host-microbe interactions and of GM functions associated with host health and diseases.
Recent studies have demonstrated that long non-coding RNAs (lncRNAs) were present in the blood of cancer patients and have shown great potential as powerful and non-invasive tumor markers. However, ...little is known about the value of lncRNAs in the diagnosis of esophageal squamous cell carcinoma (ESCC). We hypothesized that ESCC-related lncRNAs might be released into the circulation during tumor initiation and could be utilized to detect and monitor ESCC.
Ten lncRNAs (HOTAIR, AFAP1-AS1, POU3F3, HNF1A-AS1, 91H, PlncRNA1, SPRY4-IT1, ENST00000435885.1, XLOC_013104 and ENST00000547963.1) which previously found to be differently expressed in esophageal cancer were selected as candidate targets for subsequent circulating lncRNA assay. A four-stage exploratory study was conducted to test the hypothesis: (1) optimization of detected method to accurately and reproducibly measure ESCC-related lncRNAs in plasma and serum; (2) evaluation of the stability of circulating lncRNAs in human plasma or serum; (3) exploration the origin of ESCC-related lncRNAs in vitro and in vivo; (4) evaluation the diagnostic power of circulating lncRNAs for ESCC.
ESCC-related lncRNAs were detectable and stable in plasma of cancer patients, and derived largely from ESCC tumor cells. Furthermore, plasma levels of POU3F3, HNF1A-AS1 and SPRY4-IT1 were significantly higher in ESCC patients compared with normal controls. By receiver operating characteristic curve (ROC) analysis, among the three lncRNAs investigated, plasma POU3F3 provided the highest diagnostic performance for detection of ESCC (the area under the ROC curve (AUC), 0.842; p < 0.001; sensitivity, 72.8%; specificity, 89.4%). Moreover, use of POU3F3 and SCCA in combination could provide a more effective diagnosis performance (AUC, 0.926, p < 0.001, sensitivity, 85.7%; specificity, 81.4%). Most importantly, this combination was effective to detect ESCC at an early stage (80.8%).
Plasma POU3F3 could serve as a potential biomarker for diagnosis of ESCC, and the combination of POU3F3 and SCCA was more efficient for ESCC detection, in particular for early tumor screening.
Gut microbiota has been suggested to play a role in almost all major diseases including cardio- and cerebrovascular diseases. A possible mechanism is the transformation of dietary choline and ...l-carnitine into trimethylamine by gut bacteria. This metabolite is further oxidized into trimethylamine-N-oxide (TMAO) in liver and promotes atherogenesis. Nevertheless, little is known about gut microbial diversity and blood TMAO levels in stroke patients.
We performed a case-control study of patients with large-artery atherosclerotic ischemic stroke and transient ischemic attack. TMAO was determined with liquid chromatography tandem mass spectrometry. Gut microbiome was profiled using Illumina sequencing of the 16S rRNA V4 tag. Within the asymptomatic control group, participants with and without carotid atherosclerotic plaques showed similar levels of TMAO without a significant difference in gut microbiota; however, the gut microbiome of stroke and transient ischemic attack patients was clearly different from that of the asymptomatic group. Stroke and transient ischemic attack patients had more opportunistic pathogens, such as Enterobacter, Megasphaera, Oscillibacter, and Desulfovibrio, and fewer commensal or beneficial genera including Bacteroides, Prevotella, and Faecalibacterium. This dysbiosis was correlated with the severity of the disease. The TMAO level in the stroke and transient ischemic attack patients was significantly lower, rather than higher, than that of the asymptomatic group.
Participants with asymptomatic atherosclerosis did not exhibit an obvious change in gut microbiota and blood TMAO levels; however, stroke and transient ischemic attack patients showed significant dysbiosis of the gut microbiota, and their blood TMAO levels were decreased.
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