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1.
Zinc‐Air Batteries: Atomic Modulation of FeCo–Nitrogen–Carbon Bifunctional Oxygen Electrodes for Rechargeable and Flexible All‐Solid‐State Zinc–Air Battery (Adv. Energy Mater. 13/2017) 下载免费PDF全文
2.
An advanced electro-active dry adhesive,which was composed of a mushroom-shaped fibrillar dry adhesive array actuated by an Ionic Polymer Metal Composite (IPMC) artificial muscle reinforced with nitrogen-doped carbon nanocages (NCNCs),was developed to imitate the actuation of a gecko's toe.The properties of the NCNC-reinforced Nafion membrane,the electromechanical properties of the NCNC-reinforced IPMC,and the related electro-active adhesion ability were investigated.The NCNCs were uniformly dispersed in the 0.1 wt% NCNC/Nafion membrane,and there was a seamless connection with no clear interface between the dry adhesive and the IPMC.Our 0.1 wt% NCNC/Nafion-IPMC actuator shows a displacement and force that are 1.6-2 times higher than those of the recast Nafion-IPMC.This is due to the increased water uptake (25.39%) and tensile strength (24.5 MPa) of the specific 3D hollow NCNC-reinforced Nafion membrane,as well as interactions between the NCNCs and the sulfonated groups of the Nafion.The NCNC/Nafion-IPMC was used to effectively actuate the mushroom-shaped dry adhesive.The normal adhesion forces were 7.85 mN,12.1 mN,and 51.7 mN at sinusoidal voltages of 1.5 V,2.5 V,and 3.5 V,respectively,at 0.1 Hz.Under the bionic leg trail,the normal and shear forces were approximately 713.5 mN (159 mN·cm-2) and 1256.6 mN (279 mN·cm-2),respectively,which satisfy the required adhesion.This new electro-active dry adhesive can be applied for active,distributed actuation and flexible grip in robots. 相似文献
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4.
Cun-Feng Zhao Ran Wei Xian-Chun Zhang 《Cladistics : the international journal of the Willi Hennig Society》2020,36(4):443-445
Here, we publish Lepisorus sect. Paragramma (Blume) C.F. Zhao, R. Wei & X.C. Zhang as a combinatio nova to replace the section name in Zhao et al. (2020), which was published as a status nova and turned out to be an invalid name, because we cited an incorrect basionym. A revised infrageneric classification of Lepisorus also is proposed. 相似文献
5.
Chuanxiao Xie Marilyn Warburton Mingshun Li Xinhai Li Muji Xiao Zhuanfang Hao Qi Zhao Shihuang Zhang 《Molecular breeding : new strategies in plant improvement》2008,21(4):407-418
This study analyzes population structure and linkage disequilibrium (LD) among 187 commonly used Chinese maize inbred lines,
representing the genetic diversity among public, commercial and historically important lines for corn breeding. Seventy SSR
loci, evenly distributed over 10 chromosomes, were assayed for polymorphism. The identified 290 alleles served to estimate
population structure and analyze the genome-wide LD. The population of lines was highly structured, showing 6 subpopulations:
BSSS (American BSSS including Reid), PA (group A germplasm derived from modern U.S. hybrids in China), PB (group B germplasm
derived from modern U.S. hybrid in China), Lan (Lancaster Surecrop), LRC (derivative lines from Lvda Reb Cob, a Chinese landrace)
and SPT (derivative lines from Si-ping-tou, a Chinese landrace). Forty lines, which formerly had an unknown and/or miscellaneous
origin and pedigree record, were assigned to the appropriate group. Relationship estimates based on SSR marker data were quantified
in a Q matrix, and this information will inform breeder’s decisions regarding crosses. Extensive inter- and intra-chromosomal
LD was detected between 70 microsatellite loci for the investigated maize lines (2109 loci pairs in LD with D′ > 0.1 and 93 out of them at P < 0.01).This suggests that rapidly evolving microsatellites may track recent population structure. Interlocus LD decay among
the diverse maize germplasm indicated that association studies in QTLs and/or candidate genes might avoid nonfunctional and
spurious associations since most of the LD blocks were broken between diverse germplasm. The defined population structure
and the LD analysis present the basis for future association mapping.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
6.
Insights into the discrepant luminescence for BaSiO3:Eu2+ phosphors prepared by solid‐state reaction and precipitation reaction methods 下载免费PDF全文
Jiao Xu Yang Zhao Jingjing Chen Zhiyong Mao Yanfang Yang Dajian Wang 《Luminescence》2017,32(6):957-963
Two synthesis routes, solid‐state reaction and precipitation reaction, were employed to prepare BaSiO3:Eu2+ phosphors in this study. Discrepancies in the luminescence green emission at 505 nm for the solid‐state reaction method sample and in the yellow emission at 570 nm for the sample prepared by the precipitation reaction method, were observed respectively. A detail investigation about the discrepant luminescence of BaSiO3:Eu2+ phosphors was performed by evaluation of X‐ray diffraction (XRD), photoluminescence (PL)/photoluminescence excitation (PLE), decay time and thermal quenching properties. The results showed that the yellow emission was generated from the BaSiO3:Eu2+ phosphor, while the green emission was ascribed to a small amount of Ba2SiO4:Eu2+ compound that was present in the solid‐state reaction sample. This work clarifies the luminescence properties of Eu2+ ions in BaSiO3 and Ba2SiO4 hosts. 相似文献
7.
Ryota Masuzaki Sophia Zhao M. Todd Valerius Daisuke Tsugawa Yuki Oya Kevin C. Ray Seth J. Karp 《The Journal of biological chemistry》2016,291(7):3346-3358
After significant injury, the liver must maintain homeostasis during the regenerative process. We hypothesized the existence of mechanisms to limit hepatocyte proliferation after injury to maintain metabolic and synthetic function. A screen for candidates revealed suppressor of cytokine signaling 2 (SOCS2), an inhibitor of growth hormone (GH) signaling, was strongly induced after partial hepatectomy. Using genetic deletion and administration of various factors we investigated the role of SOCS2 during liver regeneration. SOCS2 preserves liver function by restraining the first round of hepatocyte proliferation after partial hepatectomy by preventing increases in growth hormone receptor (GHR) via ubiquitination, suppressing GH pathway activity. At later times, SOCS2 enhances hepatocyte proliferation by modulating a decrease in serum insulin-like growth factor 1 (IGF-1) that allows GH release from the pituitary. SOCS2, therefore, plays a dual role in modulating the rate of hepatocyte proliferation. In particular, this is the first demonstration of an endogenous mechanism to limit hepatocyte proliferation after injury. 相似文献
8.
Jiefeng He Haichao Zhao Dongfeng Deng Yadong Wang Xiao Zhang Haoliang Zhao Zongquan Xu 《Journal of cellular physiology》2020,235(3):2464-2477
This study aimed to identify significant biomarkers related to the prognosis of liver cancer using long noncoding RNA (lncRNA)-associated competing endogenous RNAs (ceRNAs) analysis. Differentially expressed mRNA and lncRNAs between liver cancer and paracancerous tissues were screened, and the functions of these mRNAs were predicted by gene ontology and pathway enrichment analyses. A ceRNA network consisting of differentially expressed mRNAs and lncRNAs was constructed. LncRNA FENDRR and lncRNA HAND2-AS1 were hub nodes in the ceRNA network. A risk score assessment model consisting of eight genes (PDE2A, ESR1, FBLN5, ALDH8A1, AKR1D1, EHHADH, ADRA1A, and GNE) associated with prognosis were developed. Multivariate Cox regression suggested that both pathologic_T and risk group could be regarded as independent prognostic factors. Furthermore, a nomogram model consisting of pathologic_T and risk group showed a good prediction ability for predicting the survival rate of liver cancer patients. The nomogram model consisting of pathologic_T and a risk score assessment model could be regarded as an independent factor for predicting prognosis of liver cancer. 相似文献
9.
10.
Zhemin Li Genhai Zhao Hui Liu Yugang Guo Hefang Wu Xiaowen Sun Xihua Wu Zhiming Zheng 《Journal of industrial microbiology & biotechnology》2017,44(7):973-985
Prenylated quinones, especially menaquinones, have significant physiological activities, but are arduous to synthesize efficiently. Due to the relaxed aromatic substrate specificity and prenylation regiospecificity at the ortho- site of the phenolic hydroxyl group, the aromatic prenyltransferase NovQ from Streptomyces may be useful in menaquinone synthesis from menadione. In this study, NovQ was overexpressed in Pichia pastoris. After fermentation optimization, NovQ production increased by 1617%. Then the different effects of metal ions, detergents and pH on the activity of purified NovQ were investigated to optimize the prenylation reaction. Finally, purified NovQ and cells containing NovQ were used for menadione prenylation in vitro and in vivo, respectively. Menaquinone-1 (MK-1) was detected as the only product in vitro with γ,γ-dimethylallyl pyrophosphate and menadione hydroquinol substrates. MK-3 at a concentration of 90.53 mg/L was detected as the major product of whole cell catalysis with 3-methyl-2-buten-1-ol and menadione hydroquinol substrates. This study realized whole cell catalysis converting menadione to menaquinones. 相似文献