<i>In Situ</i> Observation and Electrochemical Study of Encapsulated Sulfur Nanoparticles by MoS₂ Flakes

Tang, Wei,Chen, Zhongxin,Tian, Bingbing,Lee, Hyun-Wook,Zhao, Xiaoxu,Fan, Xiaofeng,Fan, Yanchen,Leng, Kai,Peng, Chengxin,Kim, Min-Ho,Li, Meng,Lin, Ming,Su, Jie,Chen, Jianyi,Jeong, Hu Young,Yin, Xuesong American Chemical Society 2017 JOURNAL OF THE AMERICAN CHEMICAL SOCIETY - Vol.139 No.29

<P>Sulfur is an attractive cathode material for next-generation lithium batteries due to its high theoretical capacity and low cost. However, dissolution of its lithiated product (lithium polysulfides) into the electrolyte limits the practical application of lithium sulfur batteries. Here we demonstrate that sulfur particles can be hermetically encapsulated by leveraging on the unique properties of two-dimensional materials such as molybdenum disulfide (MoS<SUB>2</SUB>). The high flexibility and strong van der Waals force in MoS<SUB>2</SUB> nanoflakes allows effective encapsulation of the sulfur particles and prevent its sublimation during <I>in situ</I> TEM studies. We observe that the lithium diffusivities in the encapsulated sulfur particles are in the order of 10<SUP>–17</SUP> m<SUP>2</SUP> s<SUP>–1</SUP>. Composite electrodes made from the MoS<SUB>2</SUB>-encapsulated sulfur spheres show outstanding electrochemical performance, with an initial capacity of 1660 mAh g<SUP>–1</SUP> and long cycle life of more than 1000 cycles.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/jacsat/2017/jacsat.2017.139.issue-29/jacs.7b05371/production/images/medium/ja-2017-05371c_0006.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/ja7b05371'>ACS Electronic Supporting Info</A></P>

Transcriptome analysis of colchicine-induced tetraploid Kiwifruit leaves with increased biomass and cell size

Zhu Yanyan,Tang Wei,Tang Xiaofeng,Wang Lihuan,Li Wei,Zhang Qian,Li Mingzhang,Fang Congbing,Liu Yongsheng,Wang Songhu 한국식물생명공학회 2021 Plant biotechnology reports Vol.15 No.5

Colchicine-induced polyploidization has been extensively utilized in plant-breeding programs to increase biomass and overall yield of various crop species. Chromosome doubling usually increases the plant size and cell size. However, the underly- ing mechanisms remain elusive. In this study, we showed that 0.1% colchicine is an optimized concentration for inducing tetraploidization of Actinidia chinensis var. chinensis ‘Hongyang’, a commercially important diploid kiwifruit cultivar. The tetraploid plants showed increased plant height, leaf size, and biomass, as compared with the corresponding diploid plants. Scanning electron microscopy and histological analysis indicated that the leaf cell size was significantly increased in the tetraploid plants. Our further transcriptome analysis revealed the 5922 differentially expressed genes between the diploid and tetraploid plants. Gene Ontology analysis enriched the cell wall-related genes, including the pectin methylesterases (PMEs) and expansins (EXPs), both of which play a critical role in cell wall loosening and extension. The increased expression of PME and EXP genes might contribute to the increased cell size in the tetraploid plants. Together, our work indicated that tetraploidization increases the organ and cell size in kiwifruit, possibly by enhancing the cell wall extensibility.

Clustering Strategy Based on Graph Method and Power Control for Frequency Resource Management in Femtocell and Macrocell Overlaid System

Hongjia Li,Xiaodong Xu,Dan Hu,Xiaofeng Tao,Ping Zhang,Song Ci,Hui Tang 한국통신학회 2011 Journal of communications and networks Vol.13 No.6

In order to control interference and improve spectrumef-ficiency in the femtocell and macrocell overlaid system (FMOS), we propose a joint frequency bandwidth dynamic division, clustering and power control algorithm (JFCPA) for orthogonal-frequencydivision-multiple access-based downlink FMOS. The overall system bandwidth is divided into three bands, and the macro-cellular coverage is divided into two areas according to the intensity of the interference from the macro base station to the femtocells, which are dynamically determined by using the JFCPA. A cluster is taken as the unit for frequency reuse among femtocells. We map the problem of clustering to the MAX k-CUT problem with the aim of eliminating the inter-femtocell collision interference, which is solved by a graph-based heuristic algorithm. Frequency bandwidth sharing or splitting between the femtocell tier and the macrocell tier is determined by a step-migration-algorithm-based power control. Simulations conducted to demonstrate the effectiveness of our proposed algorithm showed the frequency-reuse probability of the FMOS reuse band above 97.6% and at least 70% of the frequency bandwidth available for the macrocell tier, which means that the co-tier and the cross-tier interference were effectively controlled. Thus, high spectrum efficiency was achieved. The simulation results also clarified that the planning of frequency resource allocation in FMOS should take into account both the spatial density of femtocells and the interference suffered by them. Statistical results from our simulations also provide guidelines for actual FMOS planning.

Dual-Responsive Cross-Linked Micelles from Amphiphilic Four-Arm Star Copolymers with Different Block Ratios for Triggering DOX Release

Yunwei Huang,Yanzhe Li,Zilun Tang,Qiuping Su,Tingting Liao,Yuxin Gu,Xiaofeng Lin,Xihong Zu,Wenjing Lin,Guobin Yi 한국고분자학회 2020 Macromolecular Research Vol.28 No.8

The four-arm star copolymers poly(methacrylic acid)-poly(2-hydroxyethyl methacrylate-disulfide~)-poly(poly(ethylene glycol) methyl ether methacrylate) (4AS-PMAAx-(PHEMA-SS~)y-PPEGMAz) with four different block ratios were synthesized and could self-assembled into cross-linked polymer micelles for the exploration of the structure-property relationship. The cross-linked polymer micelles in aqueous solution had low critical micelle concentration (CMC) values (1.9-4.6 mg/L), which exhibited better stability than non-cross-linked micelles. The CMC value decreased with the increase of the length of inner PMAA core and hydrophobic PHEMA cross-linked middle layer. The blank and doxorubicin (DOX)- loaded micelles with different block ratios were prepared by dialysis with the particle sizes of 120-240 nm. The longer inner PMAA core and cross-linked middle layer enhanced the drug loading content (DLC) results and led to relatively bigger particle sizes of polymer micelles. The in vitro DOX release data revealed that DOX-loaded micelles had low DOX cumulative release percentages of 18-37% after 110 h at pH 7.4, but up to 83-90% when introducing reductant GSH at pH 5.0. The 4AS-PMAA21.2-(PHEMASS~) 13.1-PPEGMA5.1 micelles with the longest PMAA core had the largest cumulative release of 90.1%. The DOX release process and mechanism of the micelles at different conditions fitted well with the semi-empirical equation. Overall, the results demonstrated that the block ratios and pH/redox-responsiveness of these four-arm star copolymers could be well-controlled and their self-assembled cross-linked micelles as anticancer drug carrier system could be improved by optimizing the different ratios.

Clustering Strategy Based on Graph Method and Power Control for Frequency Resource Management in Femtocell and Macrocell Overlaid System

Li, Hongjia,Xu, Xiaodong,Hu, Dan,Tao, Xiaofeng,Zhang, Ping,Ci, Song,Tang, Hui The Korea Institute of Information and Commucation 2011 Journal of communications and networks Vol.13 No.6

In order to control interference and improve spectrum efficiency in the femtocell and macrocell overlaid system (FMOS), we propose a joint frequency bandwidth dynamic division, clustering and power control algorithm (JFCPA) for orthogonal-frequency-division-multiple access-based downlink FMOS. The overall system bandwidth is divided into three bands, and the macro-cellular coverage is divided into two areas according to the intensity of the interference from the macro base station to the femtocells, which are dynamically determined by using the JFCPA. A cluster is taken as the unit for frequency reuse among femtocells. We map the problem of clustering to the MAX k-CUT problem with the aim of eliminating the inter-femtocell collision interference, which is solved by a graph-based heuristic algorithm. Frequency bandwidth sharing or splitting between the femtocell tier and the macrocell tier is determined by a step-migration-algorithm-based power control. Simulations conducted to demonstrate the effectiveness of our proposed algorithm showed the frequency-reuse probability of the FMOS reuse band above 97.6% and at least 70% of the frequency bandwidth available for the macrocell tier, which means that the co-tier and the cross-tier interference were effectively controlled. Thus, high spectrum efficiency was achieved. The simulation results also clarified that the planning of frequency resource allocation in FMOS should take into account both the spatial density of femtocells and the interference suffered by them. Statistical results from our simulations also provide guidelines for actual FMOS planning.

Gemcitabine Inhibits the Progression of Pancreatic Cancer by Restraining the WTAP/MYC Chain in an m6A-Dependent Manner

Pei Cao,Weigang Zhang,Junyi Qiu,Zuxiong Tang,Xiaofeng Xue,Tingting Feng 대한암학회 2024 Cancer Research and Treatment Vol.56 No.1

Purpose Pancreatic cancer (PC) is a common malignant tumor of the digestive system, and its 5-year survival rate is only 4%. N6-methyladenosine (m6A) RNA methylation is the most common post-transcriptional modification and dynamically regulates cancer development, while its role in PC treatment remains unclear.Materials and Methods We treated PC cells with gemcitabine and quantified the overall m6A level with m6A methylation quantification. Real-time quantitative reverse transcription polymerase chain reaction and Western blot analyses were used to detect expression changes of m6A regulators. We verified the m6A modification on the target genes through m6A-immunoprecipitation (IP), and further <i>in vivo</i> experiments and immunofluorescence (IF) assays were applied to verify regulation of gemcitabine on Wilms’ tumor 1–associated protein (WTAP) and MYC.Results Gemcitabine inhibited the proliferation and migration of PC cells and reduced the overall level of m6A modification. Additionally, the expression of the “writer” WTAP was significantly downregulated after gemcitabine treatment. We knocked down WTAP in cells and found target gene MYC expression was significantly downregulated, m6A-IP also confirmed the m6A modification on MYC. Our experiments showed that m6A-MYC may be recognized by the “reader” IGF2BP1. <i>In vivo</i> experiments revealed gemcitabine inhibited the tumorigenic ability of PC cells. IF analysis also showed that gemcitabine inhibited the expression of WTAP and MYC, which displayed a significant trend of co-expression.Conclusion Our study confirmed that gemcitabine interferes with WTAP protein expression in PC, reduces m6A modification on MYC and RNA stability, thereby inhibiting the downstream pathway of MYC, and inhibits the progression of PC.

Microsatellite Markers Linked to Quantitative Trait Loci Affecting Fatness in Divergently Selected Chicken Lines for Abdominal Fat

Zhang, Hui,Wang, Shouzhi,Li, Hui,Yu, Xijiang,Li, Ning,Zhang, Qin,Liu, Xiaofeng,Wang, Qigui,Hu, Xiaoxiang,Wang, Yuxiang,Tang, Zhiquan Asian Australasian Association of Animal Productio 2008 Animal Bioscience Vol.21 No.10

Abdominal fat characters are complex and economically important in the poultry industry. Their selection may benefit from the implementation of marker-assisted selection (MAS). The objective of this study was to identify the markers linked to QTL responsible for fatness traits. The Northeast Agricultural University broiler lines divergently selected for abdominal fat content (NEAUHLF) were used in the study. A total of 596 individuals from the divergent tails from the 6th to the 10th generations were genotyped at 23 microsatellite markers on chromosome 1. The differences of allele frequencies of all marker alleles between the divergent tails across the five generations were recorded. The allele frequencies of five markers, including LEI0209, LEI0146, MCW0036, ADL328 and MCW0115, had significant differences between the two tails in all five generations. The resulting p-values using Fisher's exact test on eleven markers, containing MCW248, MCW0010, MCW0106, LEI0252, LEI0068, MCW0018, MCW0061, LEI0088, MCW200, MCW283 and ROS0025, had a decreasing tendency from the 6th to the 10th generation. Statistical analysis showed that polymorphisms of the eight markers, including LEI0209, LEI0146, ROS0025, MCW0115, MCW0010, MCW0036, MCW283, ADL328, were significantly (p<0.0011) or suggestively (p<0.05) associated with abdominal fat content (AFW and AFP) across generations. It is concluded that the eight markers could be associated with the QTL affecting the deposition of abdominal fat in broiler chickens.