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排序方式: 共有1119条查询结果,搜索用时 15 毫秒
931.
Brittany E. Jewell An Xu Dandan Zhu Mo-Fan Huang Linchao Lu Mo Liu Erica L. Underwood Jun Hyoung Park Huihui Fan Julian A. Gingold Ruoji Zhou Jian Tu Zijun Huo Ying Liu Weidong Jin Yi-Hung Chen Yitian Xu Shu-Hsia Chen Nino Rainusso Nathaniel K. Berg Danielle A. Bazer Christopher Vellano Philip Jones Holger K. Eltzschig Zhongming Zhao Benny Abraham Kaipparettu Ruiying Zhao Lisa L. Wang Dung-Fang Lee 《PLoS genetics》2021,17(12)
932.
Photocatalytic CO2 reduction to hydrocarbon fuels through solar energy provides a feasible channel for reducing CO2 emission and resource depletion. Nevertheless, severe charge recombination and high energy barrier limit the CO2 reduction efficiency. Herein, a surface amine-functionalized SnO2 with oxygen vacancies (A-Vo-SnO2) is fabricated to achieve visible-light-driven photocatalytic CO2 reduction. Specifically, amino groups modified onto the surface of the catalyst can provide more active sites to promote the adsorption of CO2. Meanwhile, the synchronously induced oxygen defect level reduces the band-gap energy and expands the light-absorption region from UV light to visible light. The oxygen vacancies can modulate the electronic structure and work as the separation centers of spatial charges, thus promoting the interfacial charge transfer efficiency and providing more catalytic sites, as evidenced by experimental observation and theoretical calculation. As expected, this A-Vo-SnO2 exhibits a CH4 evolution rate of 17.27 µmol g−1 h−1 without adding sacrificial agent and co-catalyst, much higher than 5.98 µmol g−1 h−1 of pure SnO2. This work can provide significant inspiration for the design of defect engineering based on visible-light-driven photocatalysts towards photocatalytic CO2 conversion. 相似文献
933.
Siguang Guo Zhefei Sun Yu Liu Xinbo Guo Haoqin Feng Shi Luo Changhao Wei Yang Zheng Xuming Zhang Kangwoon Kim Haodong Liu Paul K Chu Biao Gao Qiaobao Zhang Kaifu Huo 《Liver Transplantation》2024,14(13):2303876
The manipulation of stress in high-capacity microscale alloying anode materials, which undergo significant volumetric variation during cycling, is crucial prerequisite for improved their cycling capability. In this work, an innovative structural design strategy is proposed for scalable fabrication of a unique 3D highly porous micro structured germanium (Ge) featuring micro-nano hierarchical architecture as viable anode for high-performance lithium-ion batteries (LIBs). The resultant micro-sized Ge, consisting of interconnected nanoligaments and bicontinuous nanopores, is endowed with high activity, decreased Li+ diffusion distance and alleviated volume variation, appealing as an ideal platform for in-depth understanding the relationship between structural design and stress evolution. Such a micro-sized Ge being highly porous delivers a record high initial Coulombic efficiency of 92.5%, large volumetric capacity of 2,421 mAh cm−3 at 1.2 mA cm−2, exceptional rate capability (805.6 mAh g−1 at 10 Ag−1) and cycling stability (over 90% capacity retention after 1000 cycles even at 5 A g−1), largely outperforming the reported Ge-based anodes for LIBs. Furthermore, its underlying Li storage mechanism and stress dispersion behavior are explicitly revealed by combined substantial in situ/ex situ experimental characterizations and theoretical computation. This work provides novel insights into the rational design of high-performance and durable alloying anodes toward high-energy LIBs. 相似文献
934.
Yuan-Ling Yu Meng-Ting Zhang Yan Huo Ji-Liang Tang Qing Liu Xiao-Ying Chen Rong-Xiang Fang Li-Li Zhang 《Insect Science》2021,28(2):315-329
Rice stripe virus(RSV)is the causative agent of rice stripe disease and is completely dependent on insect vectors for its plant-to-plant transmission.Laodelphax striatellus is the major insect vector for RSV.In this study,we explored the interactions be-tween RSV infection and L.striatellus autophagy,a potential intrinsic antiviral mechanism in insects.We found that L.striatellus autophagic activity did not affect RSV infection;however,the autophagy related-8(Atg8)gene significantly enhanced virus infection.Dur-ing RSV initial infection within the L.striatellus midgut,silencing of Atg8 expression significantly decreased the phosphorylation of c-Jun N-terminal kinase(p-JNK);however,when RSV infection is absent,silencing of Atg8 did not alter p-JNK levels.Thesc results indicated that Atg8 might activate the JNK machinery by allowing more virus infection into cells.We further revealed that Atg8-deficiency significantly decreased RSV accumu-lation on the surface of the insect midgut epithelial cells,suggesting a receptor trafficking function of the y-aminobutyric acid receptor-associated protein family.Using the RSV ovary entry as a model,in which vitellogenin receptor(V gR)mediates RSV cell entry,we clarified that Atg8-deficiency decreased the abundance of V gR localizing on the cytomem-brane and disturbed the attachment of RSV in the germarium zones.Collectively,these results revealed an autophagy-independent function of L.striatellus Atg8 that enhances RSV initial infection by increasing virus attachment on the infection sites. 相似文献
935.
Purified chloroplast tRNAs were isolated fromPisum sativum leaves and radioactively labeled at their 3′ end using tRNA nucleotidyl transferase and α32P-labeled CTP. Pea ctDNA was fragmented using a number of restriction endonucleases and hybridized with thein vitro labeled chloroplast tRNAs by DNA transfer method. Genes for tRNAs have been found to be dispersed throughout the chloroplast
genome. A closer analysis of the several hybrid regions using recombinant DNA plasmids have shown that tRNA genes are localized
in the chloroplast genome in both single and multiple arrangements. Two dimensional gel electrophoresis of total ct tRNA have
identified 36 spots. All of them have been found to hybridize withPisum sativum ctDNA. Using recombinant clones, 30 of the tRNA spots have been mapped inPisum sativum ctDNA. 相似文献
936.
Total hip replacement has evolved into one of the most frequently performed reconstructive procedures in orthopaedic surgery today. A modified anterior approach developed by the senior surgeon has been utilized in performing over 3,000 operations in the past two decades. It is a unique and facile exposure. It can be easily applied to primary and revision surgery. Noncemented prostheses have been used in over 1,000 of these operations. This article details the surgical exposure, acetabular and femoral preparation for both non-cemented and cemented prostheses, special considerations for revision surgery, and the clinical results of the experience with noncemented prostheses to date. 相似文献
937.
寡核苷酸探针进行DNA指纹分析在法医学上应用的评价 总被引:2,自引:0,他引:2
本文用自制的寡核苷酸探针(CAC)5/(GTG)5,对与法医学应用有关的问题进行了研究。从室温下放置三年的血痕得到不完全的DNA指纹图;从同一个体不同组织的DNA得到完全一致的结果;从混合斑中分离出精子DNA进行DNA指纹检验,并与同一供体的血液DNA指纹图进行比较;还仅有0.25μg的DNA获得了可分辨的DNA指纹图。此外,用限制性内切酶HaeⅢ代替Hinfl酶切入的基因组DNA,也获得了高度多 相似文献
938.
939.
济南假单胞菌新种的抗生作用 总被引:1,自引:0,他引:1
从济南土壤中分离、筛选到Ps 161菌株。该菌株为革兰氏阴性需氧短杆菌,具有激活非蒋异性细胞免疫和特异性体液免疫的功能,能使机体获得免疫应答和免疫反应性。其菌苗对小鼠精原细胞、鼠类移植瘤有显著抑制作用,并增强吡喹酮治疗小鼠血吸虫童虫的作用。能提高人体白细胞和体液免疫功能,对人体癌性胸水和表浅转移癌实体瘤有明显的消除与抑制效果。该菌株的代谢产物对革兰氏阳性细菌有显著抑制作用。 经中国科学院徽生物研究所鉴定,该菌株为一新种,命名为济南假单胞菌(Pseudomonas tnanenses sp. Nov.)。 相似文献
940.