ABSTRACT
Lithium-sulfur (Li-S) batteries with high sulfur utilization, long-cycle life, and dendrite-free features hold great promise for the development of next-generation energy storage devices of high energy density. Considerable efforts have been committed to solving the polysulfide shuttle problem toward highly stable Li-S batteries. Here, a unique polymer network containing dually anchored ionic liquids (DA-PIL) is devolped to improve the cycling performance and coulombic efficiency of Li-S batteries. This DA-PIL electrolyte incorporates the amphiphilicity of both the polysulfides anion and lithium cation, creating an ionic function layer on polypropylene separator. Noteworthily, the DA-PIL network is "clean" in the sense that no free ionic specifies are introduced to the electrolyte system. The DA-PIL layer not only enables strong supression against polysulfide shuttling but simultaneously allows fast lithium transportation owing to cooperate electrostatic interaction among anchored cations and anions. The DA-PIL layer functionalized on a polypropylene separator can boost excellent stability of Li-S battery with >1600 h cycling test at 0.25 mA cm-2 . The Li-S cell with DA-PIL layer delivers a higher discharge capacity of 827.4 mAh g-1 at 1C. A discharge capacity of 630.6 mAh g-1 is retained after 1000 cycles.
Subject(s)
Ionic Liquids , Lithium , Polypropylenes , Polymers , SulfurABSTRACT
Room-temperature sodium-sulfur (RT-Na-S) batteries are attracting increased attention due to their high theoretical energy density and low-cost. However, the traditional RT-Na-S batteries assembled with glass fiber (GF) separators are still hindered by the polysulfide shuttle effect and sodium dendrite growth, limiting the battery's capacity and cycling stability. Here, a facile and effective method toward commercial polyolefin separators for constructing stable RT-Na-S batteries is presented. By coating commercial polypropylene membrane with core-shell structured MXene@C nanosheets, a powerful dual-functional separator with improved electrolyte wettability that can inhibit polysulfide migration and induce uniform sodium disposition is developed. More importantly, the modified separator can also accelerate the conversion kinetics of sodium polysulfides. Benefiting from these characteristics, the as-prepared RT-Na-S battery exhibits a remarkably enhanced capacity (1159 mAh g-1 at 0.2 C) and excellent cycling performance (95.8% of capacity retention after 650 cycles at 0.5 C). This study opens a promising avenue for the development of high-performance Na-S batteries.
ABSTRACT
Global warming has reduced the productivity of many field-grown crops, as the effects of high temperatures can lead to male sterility in such plants. Genetic regulation of the high temperature (HT) response in the major crop cotton is poorly understood. We determined the functionality and transcriptomes of the anthers of 218 cotton accessions grown under HT stress. By analyzing transcriptome divergence and implementing a genome-wide association study (GWAS), we identified three thermal tolerance associated loci which contained 75 protein coding genes and 27 long noncoding RNAs, and provided expression quantitative trait loci (eQTLs) for 13 132 transcripts. A transcriptome-wide association study (TWAS) confirmed six causal elements for the HT response (three genes overlapped with the GWAS results) which are involved in protein kinase activity. The most susceptible gene, GhHRK1, was confirmed to be a previously uncharacterized negative regulator of the HT response in both cotton and Arabidopsis. These functional variants provide a new understanding of the genetic basis for HT tolerance in male reproductive organs.
Subject(s)
Genome-Wide Association Study , Infertility, Male , Gossypium/genetics , Humans , Male , Quantitative Trait Loci/genetics , Temperature , Transcriptome/geneticsABSTRACT
High-temperature (HT) stress induces male sterility, leading to yield reductions in crops. DNA methylation regulates a range of processes involved in plant development and stress responses, but its role in male sterility under HT remains unknown. Here, we investigated DNA methylation levels in cotton (Gossypium hirsutum) anthers under HT and normal temperature (NT) conditions by performing whole-genome bisulfite sequencing to investigate the regulatory roles of DNA methylation in male fertility under HT. Global disruption of DNA methylation, especially CHH methylation (where H = A, C, or T), was detected in an HT-sensitive line. Changes in the levels of 24-nucleotide small-interfering RNAs were significantly associated with DNA methylation levels. Experimental suppression of DNA methylation led to pollen sterility in the HT-sensitive line under NT conditions but did not affect the normal dehiscence of anther walls. Further transcriptome analysis showed that the expression of genes in sugar and reactive oxygen species (ROS) metabolic pathways were significantly modulated in anthers under HT, but auxin biosynthesis and signaling pathways were only slightly altered, indicating that HT disturbs sugar and ROS metabolism via disrupting DNA methylation, leading to microspore sterility. This study opens up a pathway for creating HT-tolerant cultivars using epigenetic techniques.
Subject(s)
Flowers/genetics , Flowers/physiology , Gene Expression Regulation, Plant/genetics , Gossypium/genetics , Gossypium/physiology , DNA Methylation/genetics , Flowers/metabolism , Gene Expression Regulation, Plant/physiology , Gossypium/metabolism , Hot Temperature , Reactive Oxygen Species/metabolismABSTRACT
Cotton (Gossypium spp.) is one of the most important economic crops and exhibits yield-improving heterosis in specific hybrid combinations. The genic male-sterility system is the main strategy used for producing heterosis in cotton. To better understand the mechanisms of male sterility in cotton, we carried out two-dimensional electrophoresis (2-DE) and label-free quantitative proteomics analysis in the anthers of two near-isogenic lines, the male-sterile line 1355A and the male-fertile line 1355B. We identified 39 and 124 proteins that were significantly differentially expressed between these two lines in the anthers at the tetrad stage (stage 7) and uninucleate pollen stage (stage 8), respectively. Gene ontology-based analysis revealed that these differentially expressed proteins were mainly associated with pyruvate, carbohydrate, and fatty acid metabolism. Biochemical analysis revealed that in the anthers of line 1355A, glycolysis was activated, which was caused by a reduction in fructose, glucose, and other soluble sugars, and that accumulation of acetyl-CoA was increased along with a significant increase in C14:0 and C18:1 free fatty acids. However, the activities of pyruvate dehydrogenase and fatty acid biosynthesis were inhibited and fatty acid ß-oxidation was activated at the translational level in 1355A. We speculate that in the 1355A anther, high rates of glucose metabolism may promote fatty acid synthesis to enable anther growth. These results provide new insights into the molecular mechanism of genic male sterility in upland cotton.
Subject(s)
Fatty Acids/metabolism , Gossypium/metabolism , Plant Proteins/metabolism , Pollen , Proteomics , Acetyl Coenzyme A/metabolism , Carboxylic Acids/metabolism , Glycolysis , Oxidation-Reduction , Pyruvic Acid/metabolismABSTRACT
High temperature stress is an inevitable environmental factor in certain geographical regions. To study the effect of day and night high temperature stress on male reproduction, the heat-sensitive cotton line H05 was subjected to high temperature stress. High day/normal night (HN) and normal day/high night (NH) temperature treatments were compared with normal day/normal night (NN) temperature as a control. At the anther dehiscence stage, significant differences were observed, with a reduction in flower size and filament length, and sterility in pollen, seen in NH more than in HN. A total of 36 806 differentially expressed genes were screened, which were mainly associated with fatty acid and jasmonic acid (JA) metabolic pathways. Fatty acid and JA contents were reduced more in NH than HN. Under NH, ACYL-COA OXIDASE 2 (ACO2), a JA biosynthesis gene, was down-regulated. Interestingly, aco2 CRISPR-Cas9 mutants showed male sterility under the NN condition. The exogenous application of methyl jasmonate to early-stage buds of mutants rescued the sterile pollen and indehiscent anther phenotypes at the late stage. These data show that high temperature at night may affect fatty acid and JA metabolism in anthers by suppressing GhACO2 and generate male sterility more strongly than high day temperature.
Subject(s)
Fatty Acids , Infertility, Male , Cyclopentanes , Flowers , Gene Expression Regulation, Plant , Humans , Male , Oxylipins , TemperatureABSTRACT
Lithium-sulfur (Li-S) batteries are considered as one of the most potential next-generation rechargeable batteries due to their high theoretical energy density. However, some critical issues, such as low capacity, poor cycling stability, and safety concerns, must be solved before Li-S batteries can be used practically. During the past decade, tremendous efforts have been devoted to the design and synthesis of electrode materials. Benefiting from their tunable structural parameters, hollow porous carbon materials (HPCM) remarkably enhance the performances of both sulfur cathodes and lithium anodes, promoting the development of high-performance Li-S batteries. Here, together with the templated synthesis of HPCM, recent progresses of Li-S batteries based on HPCM are reviewed. Several important issues in Li-S batteries, including sulfur loading, polysulfide entrapping, and Li metal protection, are discussed, followed by a summary on recent research on HPCM-based sulfur cathodes, modified separators, and lithium anodes. After the discussion on emerging technical obstacles toward high-energy Li-S batteries, prospects for the future directions of HPCM research in the field of Li-S batteries are also proposed.
ABSTRACT
This study evaluated the therapeutic effects and toxic reactions of combining transcatheter arterial chemoembolization (TACE) and intensity-modulated radiotherapy (IMRT) with sorafenib for the treatment of advanced hepatocellular carcinoma (HCC) patients with macrovascular invasion (MVI). We retrospectively analyzed the clinical data of 82 HCC patients with MVI, among whom 35 were treated with TACE plus IMRT alone, and 47 were treated with the combined therapy of TACE, IMRT, and sorafenib. The progression-free survival (PFS), overall survival (OS), and adverse events were assessed. The baseline characteristics were comparable between the 2 groups (all P > .05). In the TACE plus IMRT plus sorafenib group, the median PFS was 17.2 months (95% confidence interval, 14.1-19.9), significantly longer than the 9.4 months (95% confidence interval, 6.8-11.2) observed in the TACE plus IMRT group (P < .001). Additionally, patients treated with the TACE plus IMRT plus sorafenib showed a longer median OS than those treated with TACE plus IMRT alone (24.1 vs 17.3 months; P < .001). The occurrence rates of grade 1 to 2 hand-foot syndrome, other skin reactions, diarrhea, and hair loss were higher in the TACE plus IMRT plus sorafenib group (all P < .05). There were no grade 4 or higher adverse events in either group. The combination of TACE plus IMRT with sorafenib provided substantial clinical benefits in the treatment of HCC patients with MVI, increasing the tumor response rate and prolonging both PFS and OS. This approach demonstrated a tolerable and manageable safety profile.
Subject(s)
Antineoplastic Agents , Carcinoma, Hepatocellular , Chemoembolization, Therapeutic , Liver Neoplasms , Radiotherapy, Intensity-Modulated , Humans , Carcinoma, Hepatocellular/pathology , Sorafenib/therapeutic use , Radiotherapy, Intensity-Modulated/adverse effects , Liver Neoplasms/pathology , Retrospective Studies , Chemoembolization, Therapeutic/adverse effects , Antineoplastic Agents/therapeutic useABSTRACT
[This retracts the article DOI: 10.1039/C9RA04735B.].
ABSTRACT
Single-layer graphene/TPU composite foams with different graphene content were prepared through a thermally induced phase separation (TIPS) process. Multilayer graphene/TPU composite foams were fabricated by bonding single-layer foams together. The arrangement of single-layer graphene/TPU composite foams in different orders could realize a gradient distribution of the graphene to endow the multilayer foams with good impedance matching characteristics. Facile regulation of the effective absorption bandwidth (EB) value and minimum reflection loss (RLmin) have been realized by adjusting the thickness and layer number or altering the combinatorial mode of single-layer foams with different graphene contents to endow these multilayered composite foams with optimal microwave-absorbing (MA) properties. In addition, the mechanism of microwave dissipation by gradient multilayers and porous structures has been elucidated. The EB values of the multilayer foams were all wider than those of their corresponding single-layer foams with the same graphene content and multilayer foams displayed much lower RLmin than single-layer foams. Among all the multilayer foams, 2L graphene/TPU composite foams with a thickness of 5 mm exhibit the widest EB value of 9.9 GHz and the lower RLmin (-36.7 dB) while 5L graphene/TPU composite foams with a thickness of only 2.5 mm show the lowest RLmin of -43.7 dB and wider EB values (5.3 GHz).
ABSTRACT
A broadband electromagnetic wave (EW) absorbing material should possess both wider effective absorption bandwidth and lower minimum reflection loss, depending on good impedance matching between the absorber and air and strong attenuation of EW. In this study, single-layer graphene/thermoplastic polyurethane (TPU) composite foams with different foam ratios and alternating multilayer graphene/TPU composite foams with different numbers of layers were prepared. Not only was the EW-absorbing mechanism of these composite foams examined, but also the relationship between the EW-absorbing properties and the number of layers were investigated. The single-layer sample S-5 with good impedance matching characteristics and S-3 with strong EW attenuation characteristics were selected as the constituent layers to design alternating multilayer graphene/TPU composite foams. Compared to the single-layer sample 4L-C (4L-C is defined as the monolayer sample S-4 with a thickness of 9 mm), the 4L alternating multilayer graphene/TPU composite foams could achieve more than 90% EW absorption in a wide frequency band of 8.5 GHz, and its minimum reflection loss was as low as -37.67 dB, which are very beneficial for its use as a lightweight, flexible electromagnetic wave absorbing material (EWAM) for broadband absorption. More importantly, the absorption of the obtained alternating multilayer composite foams could be simply modulated not only by the absorber thickness, but also by the number of layers to satisfy the applications in different frequency bands.