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Yong Jun Gong Jung Woon Heo Hakji Lee Hyunjin Kim Jinil Cho Seonmi Pyo Heejun Yun Heebae Kim Sang Yoon Park Jeeyoung Yoo Youn Sang Kim 《Liver Transplantation》2020,10(27)
Li metal, which has a high theoretical specific capacity and low redox potential, is considered to the most promising anode material for next‐generation Li ion‐based batteries. However, it also exhibits a disadvantageous solid electrolyte interphase (SEI) layer problem that needs to be resolved. Herein, an advanced separator composed of reduced graphene oxide fiber attached to aramid paper (rGOF‐A) is introduced. When rGOF‐A is applied, F? anions, generated from the decomposition of the LiPF6 electrolyte during the SEI layer formation process form semi‐ionic C? F bonds along the surface of rGOF. As Li+ ions are plated, the “F‐doped” rGO surface induces the formation of LiF, which is known as a component of a chemically stable SEI, therefore it helps the Li metal anode to operate stably at a high current of 20 mA cm?2 with a high capacity of 20 mAh cm?2. The proposed rGOF‐A separator successfully achieves a stable SEI layer that could resolve the interfacial issues of the Li metal anode. 相似文献
123.
Tao Jiang Hao Pang Jie An Pinjing Lu Yawei Feng Xi Liang Wei Zhong Zhong Lin Wang 《Liver Transplantation》2020,10(23)
Ocean wave energy is a promising renewable energy source, but harvesting such irregular, “random,” and mostly ultra‐low frequency energies is rather challenging due to technological limitations. Triboelectric nanogenerators (TENGs) provide a potential efficient technology for scavenging ocean wave energy. Here, a robust swing‐structured triboelectric nanogenerator (SS‐TENG) with high energy conversion efficiency for ultra‐low frequency water wave energy harvesting is reported. The swing structure inside the cylindrical TENG greatly elongates its operation time, accompanied with multiplied output frequency. The design of the air gap and flexible dielectric brushes enable mininized frictional resistance and sustainable triboelectric charges, leading to enhanced robustness and durability. The TENG performance is controlled by external triggering conditions, with a long swing time of 88 s and a high energy conversion efficiency, as well as undiminished performance after continuous triggering for 4 00 000 cycles. Furthermore, the SS‐TENG is demonstrated to effectively harvest water wave energy. Portable electronic devices are successfully powered for self‐powered sensing and environment monitoring. Due to the excellent performance of the distinctive mechanism and structure, the SS‐TENG in this work provides a good candidate for harvesting blue energy on a large scale. 相似文献
124.
目的:探讨食道癌组织微小RNA-21(miR-21)、微小RNA-182(miR-182)表达与临床病理特征及预后的关系。方法:选取2011年4月到2013年7月期间在我院接受手术治疗的食道癌患者84例,取患者的癌组织和癌旁正常组织作为检验标本,比较癌组织和癌旁正常组织中miR-21、mi R-182的表达水平,并分析食道癌组织中mi R-182、mi R-21的表达与临床病理特征及预后的关系。结果:癌组织中mi R-21、mi R-182的相对表达量明显高于癌旁正常组织,差异有统计学意义(P<0.05)。食道癌组织中mi R-21的表达与淋巴结转移、临床分期有关(P<0.05),与性别、年龄、分化程度、肿瘤大小无关(P>0.05);食道癌患者癌组织中miR-182的表达与年龄、性别、肿瘤大小无关(P>0.05),与分化程度、临床分期、淋巴结转移有关(P<0.05)。食道癌癌组织中miR-21、miR-182高表达患者的中位生存时间均低于低表达患者,差异有统计学意义(P<0.05)。结论:食道癌组织mi R-21、mi R-182表达与患者的部分临床病理特征及预后有关,两者有望成为食道癌新的治疗靶点。 相似文献
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Tian Chan Deng Tao Zhu Xiuhuang Gong Chen Zhao Yangyu Wei Yuan Li Rong Xu Xiufeng He Miaonan Zhang Zhiwei Cheng Jing BenWillem Mol Qiao Jie 《中国科学:生命科学英文版》2020,63(3):319-328
In China,the medical guidelines recommend performing noninvasive prenatal testing (NIPT) with caution for pregnant women aged 35 years or older.However,the Mother and Child Health Care Law suggests that all primiparous women whose age is older than 35 years undergo prenatal diagnosis.These two inconsistent suggestions/recommendations have made obstetricians confused about whether to offer NIPT to these older pregnant women.To face this issue and find out the solution we performed a retrospective study of 189,809 NIPT samples collected from 28 provincial-leveled administrative units in China.Of 1,564women with high-risk pregnancies who underwent NIPT,459 (29.3%) did not participate in follow-up.The compound sensitivity and specificity of NIPT for trisomies 21,18 and 13 detection was 99.1%(95%CI,98.0%-99.6%) and 99.9%(95%CI,98.8%-99.9%),respectively.In secundiparous women,NIPT showed high sensitivity and specificity similar to that in primiparous women.The observed risk for trisomies 21 and 18 significantly increased when the maternal age was 39 and older.After the publication of the current NIPT policy,the follow-up rate at our center was 97.9%;however,a large number of women are not in maternal and infant care networks nationwide,and that makes the follow-up rate outside our center relatively low.Our study shows that to balance the prevention of major aneuploidies and the limited resources for prenatal diagnosis,the cut-off age of 35for invasive prenatal diagnosis might be unnecessary.Although the NIPT guidelines are well written,how to practice it effectively,especially in less industrialized areas,is worth discussing. 相似文献
127.
Hu Yongfeng Kang Ying Liu Xi Cheng Min Dong Jie Sun Lilian Zhu Yafang Ren Xianwen Yang Qianting Chen Xinchun Jin Qi Yang Fan 《中国科学:生命科学英文版》2020,63(10):1522-1533
An improved understanding of the lung microbiome may lead to better strategies to diagnose, treat, and prevent pulmonary tuberculosis(PTB). However, the characteristics of the lung microbiomes of patients with TB remain largely undefined. In this study, 163 bronchoalveolar lavage(BAL) samples were collected from 163 sputum-negative suspected PTB patients. Furthermore, 12 paired BAL samples were obtained from 12 Mycobacterium tuberculosis-positive(MTB+) patients before and after negative conversion following a two-month anti-TB treatment. The V3–V4 region of the 16 S ribosomal RNA(rRNA) gene was used to characterize the microbial composition of the lungs. The results showed that the prevalence of MTB in the BAL samples was 42.9%(70/163) among the sputum-negative patients. The α-diversity of lung microbiota was significantly less diverse in MTB+ patients compared with Mycobacterium tuberculosis-negative(MTB–) patients. There was a significant difference in β-diversity between MTB+ and MTB– patients. MTB+ patients were enriched with Anoxybacillus, while MTB– patients were enriched with Prevotella, Alloprevotella, Veillonella, and Gemella. There was no significant difference between the Anoxybacillus detection rates of MTB+ and MTB– patients. The paired comparison between the BAL samples from MTB+ patients and their negative conversion showed that BAL negative-conversion microbiota had a higher α-diversity. In conclusion, distinct features of airway microbiota could be identified between samples from patients with and without MTB. Our results imply links between lung microbiota and different clinical groups of active PTB. 相似文献
128.
Shen He Wu Shuyu Chen Xi Xu Bai Ma Dezun Zhao Yannan Zhuang Yan Chen Bing Hou Xianglin Li Jiayin Cao Yudong Fu Xianyong Tan Jun Yin Wen Li Juan Meng Li Shi Ya Xiao Zhifeng Jiang Xingjun Dai Jianwu 《中国科学:生命科学英文版》2020,63(12):1879-1886
Science China Life Sciences - Spinal cord injury (SCI), especially complete transected SCI, leads to loss of cells and extracellular matrix and functional impairments. In a previous study, we... 相似文献
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种间的遗传差异是物种分类和确定保护管理单元的基础,本研究利用DNA条形码技术对未知样本进行鉴定,通过NCBI进行BLAST得到结果是:与绿孔雀的同源性为96%。近一步通过对蓝孔雀(Pavo cristatus)和绿孔雀(Pavo muticus)线粒体细胞色素C氧化酶Ⅰ(cytochrome coxidaseⅠ,COⅠ)基因及线粒体基因组的比较分析,结果表明两物种间的COⅠ基因在碱基组成、核苷酸多样性等各项指标上均具有明显差异。遗传距离分析结果表明蓝孔雀与绿孔雀种内遗传距离为分别0和0.012,种间遗传距离为0.045,表明种间仍具有明显的遗传差异。通过对两物种线粒体基因组各基因的比较分析,发现ND1基因变异位点所占比例相对较高,考虑作为绿孔雀和蓝孔雀种群遗传学研究的最优分子标记。本研究将为分析孔雀类群间的系统发育及制定绿孔雀的保护措施提供了更多科学依据。 相似文献