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排序方式: 共有6125条查询结果,搜索用时 15 毫秒
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Philipp Kasper Jaco Selle Christina Vohlen Rebecca Wilke Celien Kuiper-Makris Oleksiy Klymenko Inga Bae-Gartz Charlotte Schmig Alexander Quaas Bjrn Schumacher Münevver Demir Martin Bürger Sonja Lang Anna Martin Hans-Michael Steffen Tobias Goeser Jrg Dtsch Miguel A. Alejandre Alcazar 《International journal of molecular sciences》2022,23(10)
Maternal obesity predisposes for hepato-metabolic disorders early in life. However, the underlying mechanisms causing early onset dysfunction of the liver and metabolism remain elusive. Since obesity is associated with subacute chronic inflammation and accelerated aging, we test the hypothesis whether maternal obesity induces aging processes in the developing liver and determines thereby hepatic growth. To this end, maternal obesity was induced with high-fat diet (HFD) in C57BL/6N mice and male offspring were studied at the end of the lactation [postnatal day 21 (P21)]. Maternal obesity induced an obese body composition with metabolic inflammation and a marked hepatic growth restriction in the male offspring at P21. Proteomic and molecular analyses revealed three interrelated mechanisms that might account for the impaired hepatic growth pattern, indicating prematurely induced aging processes: (1) Increased DNA damage response (γH2AX), (2) significant upregulation of hepatocellular senescence markers (Cdnk1a, Cdkn2a); and (3) inhibition of hepatic insulin/insulin-like growth factor (IGF)-1-AKT-p38-FoxO1 signaling with an insufficient proliferative growth response. In conclusion, our murine data demonstrate that perinatal obesity induces an obese body composition in male offspring with hepatic growth restriction through a possible premature hepatic aging that is indicated by a pathologic sequence of inflammation, DNA damage, senescence, and signs of a possibly insufficient regenerative capacity. 相似文献
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Organic Ferroelectric‐Based 1T1T Random Access Memory Cell Employing a Common Dielectric Layer Overcoming the Half‐Selection Problem 下载免费PDF全文
Qiang Zhao Hanlin Wang Zhenjie Ni Jie Liu Yonggang Zhen Xiaotao Zhang Lang Jiang Rongjin Li Huanli Dong Wenping Hu 《Advanced materials (Deerfield Beach, Fla.)》2017,29(34)
Organic electronics based on poly(vinylidenefluoride/trifluoroethylene) (P(VDF‐TrFE)) dielectric is facing great challenges in flexible circuits. As one indispensable part of integrated circuits, there is an urgent demand for low‐cost and easy‐fabrication nonvolatile memory devices. A breakthrough is made on a novel ferroelectric random access memory cell (1T1T FeRAM cell) consisting of one selection transistor and one ferroelectric memory transistor in order to overcome the half‐selection problem. Unlike complicated manufacturing using multiple dielectrics, this system simplifies 1T1T FeRAM cell fabrication using one common dielectric. To achieve this goal, a strategy for semiconductor/insulator (S/I) interface modulation is put forward and applied to nonhysteretic selection transistors with high performances for driving or addressing purposes. As a result, high hole mobility of 3.81 cm2 V?1 s?1 (average) for 2,6‐diphenylanthracene (DPA) and electron mobility of 0.124 cm2 V?1 s?1 (average) for N ,N ′‐1H,1H‐perfluorobutyl dicyanoperylenecarboxydiimide (PDI‐FCN2) are obtained in selection transistors. In this work, we demonstrate this technology's potential for organic ferroelectric‐based pixelated memory module fabrication. 相似文献
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Grain‐Boundary “Patches” by In Situ Conversion to Enhance Perovskite Solar Cells Stability 下载免费PDF全文
Lang Liu Sheng Huang Yue Lu Pengfei Liu Yizhou Zhao Congbo Shi Siyu Zhang Jiafeng Wu Haizheng Zhong Manling Sui Huanping Zhou Haibo Jin Yujing Li Qi Chen 《Advanced materials (Deerfield Beach, Fla.)》2018,30(29)
The power conversion efficiency of organic–inorganic hybrid perovskite solar cells has increased rapidly, but the device stability remains a big challenge. Previous studies show the grain boundary (GB) can facilitate ion migration and initiate device degradation. Herein, methimazole (MMI) is employed for the first time to construct a surface “patch” by in situ converting residual PbI2 at GBs. The resultant MMI–PbI2 complex can effectively suppress ion migration and inhibit diffusion of the metal electrodes. The origin of the surface “patch” effect and their working mechanisms are investigated experimentally and theoretically at the microscopic level. It hence demonstrates a simple and effective method to prolong the device stability in the context of GB engineering, which could be extensively applied to perovskite‐based optoelectronics. 相似文献
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AES密码是目前主流应用的加密算法,研究了在面积优化的同时兼顾加密速度的解决方法.根据字节代换的要求和特点,S盒变换采用16×16位的空间预存储置换表,通过O(1)查表效率即可实现SubBytes变换.将伽罗华域上所有元素的两倍先存储在一张表格中,相应运算只需要通过查表和相加就可以完成,避免了有限域的乘法运算,有效减少了运算次数.密钥扩展是独立于加密算法本身的一个特殊模块,采用上升沿有效的时钟控制密钥生成方法,在生成密钥的同一个时钟周期下降沿进行密钥传递,减少了系统延时,增强了并行性,使得面积优化后的AES加密效率更高,吞吐量更大.通过计数器控制加密函数调用的轮数,使得每个模块能多次被调用,从而使得加密芯片面积减少.实验表明在Xilinx Virtex-5 FPGA上优化后的加密模块所占用面积为11 163 Slices,相比优化之前的20 173 Slices,占用面积减少了将近一半. 相似文献
99.
The coordination arrival problems of first‐order multi‐agent systems with the arriving structure and the time structure requirements are considered for the cases with no obstacle and obstacle. To describe the distributed coordination arrival problems, we first introduce needed definitions, such as coordination arrival, threat point, and arrival structure. By selecting the estimated value of the arriving time of the agent as variable, we then develop a central estimating algorithm, which is used to construct the arriving protocols. Based on the estimating algorithm, we build and analyze coordination arriving protocols for the proposed coordination arrival problems. Several simulation examples are presented to validate the proposed algorithms. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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稠油油藏进入开发中后期,动用不均、低压低产、汽窜等矛盾日益突出,严重影响稠油开发效果.二氧化碳、氮气助排等复合吞吐技术在现场应用中存在措施针对性差、施工周期长、生产时率低等问题.为此,研制了投球器、双作用封隔器、可逆注入阀球等核心工具,将分层注汽机械管柱与复合吞吐技术有机结合,形成了稠油复合吞吐配套管柱技术,一次投放管... 相似文献