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Small molecule agonist of mitochondrial fusion repairs mitochondrial dysfunction 期刊论文  OAI收割
NATURE CHEMICAL BIOLOGY, 2023, 卷号: 19, 期号: 4, 页码: 468-+
作者:  Guo,Yingjie;  Zhang,Huan;  Yan,Chen;  Shen,Birong;  Zhang,Yue
  |  收藏  |  浏览/下载：18/0  |  提交时间：2024/07/25
Anti-Adipogenic Lanostane-Type Triterpenoids from the Edible and Medicinal Mushroom Ganoderma applanatum 期刊论文  OAI收割
JOURNAL OF FUNGI, 2022, 卷号: 8, 期号: 4, 页码: 331
作者:  Peng, Xing-Rong;  Wang, Qian;  Su, Hai-Guo;  Zhou, Lin;  Xiong, Wen-Yong
  |  收藏  |  浏览/下载：7/0  |  提交时间：2024/04/30
Constraining the X-Ray-Infrared Spectral Index of Second-timescale Flares from SGR 1935+2154 with Palomar Gattini-IR 期刊论文  OAI收割
The Astrophysical Journal, 2020, 卷号: 901, 页码: L7
作者:  HXMT
  |  收藏  |  浏览/下载：24/0  |  提交时间：2022/02/08
Radio transient sources  Magnetars  Soft gamma-ray repeaters  2008  992  1471  Astrophysics - High Energy Astrophysical Phenomena  Astrophysics - Instrumentation and Methods for Astrophysics  Abstract: The Galactic magnetar SGR 1935+2154 has been reported to produce the first example of a bright millisecond-duration radio burst (FRB 200428) similar to the cosmological population of fast radio bursts (FRBs). The detection of a coincident bright X-ray burst represents the first observed multiwavelength counterpart of an FRB. However, the search for similar emission at optical wavelengths has been hampered by the high inferred extinction on the line of sight. Here, we present results from the first search for second-timescale emission from the source at near-infrared (NIR) wavelengths using the Palomar Gattini-IR observing system in the J band, enabled by a novel detector readout mode that allows short exposure times of ?0.84 s with 99.9% observing efficiency. With a total observing time of ?12 hr (?47,728 images) during its 2020 outburst, we place median 3Ҡlimits on the second-timescale NIR fluence of ?18 Jy ms (13.1 AB mag). The corresponding extinction-corrected limit is ?125 Jy ms for an estimated extinction of AJ = 2.0 mag. Our observations were sensitive enough to easily detect an NIR counterpart of FRB 200428 if the NIR emission falls on the same power law as observed across its radio to X-ray spectrum. We report nondetection limits from epochs of four simultaneous X-ray bursts detected by the Insight-HXMT and NuSTAR telescopes during our observations. These limits provide the most stringent constraints to date on fluence of flares at 1014 Hz, and constrain the fluence ratio of the NIR emission to coincident X-ray bursts to RNIR ? 0.025 (fluence index ?0.35).  
User Experience of Tactile Feedback on a Smartphone: Effects of Vibration Intensity, Times and Interval 会议论文  OAI收割
Orlando, FL, United states, July 26, 2019 - July 31, 2019
作者:  Tan, Jun;  Ge, Yan;  Sun, Xianghong;  Zhang, Yubo;  Liu, Yanfang
  |  收藏  |  浏览/下载：48/0  |  提交时间：2019/11/08
食用蔬菜能吸收和积累微塑料 期刊论文  OAI收割
科学通报, 2019, 卷号: 64, 期号: 9, 页码: 928-934
作者:  李连祯;  周倩;  尹娜;  涂晨;  骆永明
  |  收藏  |  浏览/下载：146/0  |  提交时间：2020/06/17
微塑料  生菜  聚苯乙烯微球  吸收  积累  健康风险  microplastics  lettuce  polystyrene microbeads  uptake  accumulation  human health risk  Microplastic (MP, 100 nm-5 mm) may present an attributable risk to ecosystem and human health, and its pollution has become a global environmental concern. Despite a wealth of information on the accumulation of MPs in aquatic species, there is no information on the uptake and accumulation of MPs by higher plants. Terrestrial edible plants are directly exposed to MPs when agricultural soil was applied with organic manure, sewage sludge as fertilizer or plastic mulching. In this paper, the uptake of two sizes of polystyrene (PS) microbeads (0.2 and 1.0 mum) and then their distribution and migration in an edible plant lettuce were firstly investigated based on laboratory experiments. We used fluorescent markers to track PS microbeads in plant tissues and found fluorescence to be a sensitive and reliable detection method. Sections from untreated control lettuce showed no autofluorescence. When roots were treated with fluorescently labeled PS microbeads, the microbeads could be identified by its fluorescence. Our main study investigated the uptake of 0.2 mum beads, as few luminescence signals were observed in lettuce roots for 1.0 mum beads in our experiment. We observed that 0.2 mum fluorescent microbeads were extracellularly trapped in the root cap mucilage (which is a highly hydrated polysaccharide) and a dark green tip (which was typical of lettuce roots exposed to label PS beads) was usually visible to the naked eye. Confocal images revealed that the PS luminescence signals were mainly located in the vascular system and on the cell walls of the cortex tissue of the roots, indicated that the beads passed through the intercellular space via the apoplastic transport system. Once inside the central cylinder, the 0.2 mum PS beads were transferred from the roots to the stems and leaves via the vascular system following the transpiration stream. We also observed that the PS beads adhered to one another and self-assembled systematically into grape-like and (chain) string-like clusters in the intercellular space of the root and stem vascular tissue of lettuce plant. In contrast to the root and stem, PS beads were dispersed in the leaf tissue. Here, for the first time we provide evidence of the adherence, uptake, accumulation, and translocation of submicrometer MPs within an edible plant. Our findings highlight the previously underappreciated human exposure pathway to MPs through the consumption of contaminated crops and emphasize the need for new management strategies to control the release of MPs waste products into the terrestrial environment. Ultimately, the potential impacts of low range sized MPs on food safety of crop plants and human health need to be urgently considered.  
Mid-late Pleistocene glacial evolution in the Grove Mountains, East Antarctica, constraints from cosmogenic Be-10 surface exposure dating of glacial erratic cobbles 期刊论文  OAI收割
QUATERNARY SCIENCE REVIEWS, 2016, 卷号: 145, 期号: 0, 页码: 71-81
作者:  Dong, GC (Dong, Guocheng);  Huang, FX (Huang, Feixin);  Caffee, MW (Caffee, Marc W.);  Huang, FX;  Yi, CL (Yi, Chaolu)
  |  收藏  |  浏览/下载：29/0  |  提交时间：2017/09/26
Glacial HisTories From The East Antarctic Ice Sheet (Eais) Provide Keys To UnderstAndIng Correlations Between The Eats And Global Climate. They Are Especially Helpful In The Assessment Of Global Sea Level Change  And As a Means Of Quantifying The Magnitude Of pAst Glacial Activity And The RAte At Which Ice Responded To climAte Change. Given The Significance Of Eais Glacial hisTories  It Is Imperative That More Glacial Chronologic Data For thIs Region Be Obtained  Especially For The Mid-to-lAte Pleistocene. We Report Cosmogenic Be-10 Surface Exposure DAtIng Results From Glacially Transported Cobbles Embedded In Blue-ice moraIne MAterial At Mount hardIng  The Grove Mountains  Eais. Forty Exotic Cobbles Sampled AlOng Two PrOfiles (a And b) On This Blue-ice MoraIne Present Apparent Exposure-ages RangIng From 7.2 To 542.2 Ka. We Explore This Scattered Dataset By UsIng PrIncipal compOnent Analysis (Pca) To Identify Statistically Significant Trends In The Data. We Identify a correlatiOn betWeen Exposure-age And Distance Of The Cobbles From Mount hardIng. In prOfile a  Cobbles Further From Mount HardIng Yield Older Exposure-ages Than Those That Are Relatively Close. In Profile b  Cobbles Closer To Mount HardIng Are Found To Have Relatively Older Exposure-ages. In Term Of Glacial hisTory We Suggest That The Direction Of Ice Flow Changed durIng The Period From Similar To 60 To 200 Ka  And That Multiple Glacial Fluctuations Occurred In The Mid-late Pleistocene. (c) 2016 Elsevier Ltd. All Rights Reserved.  
Effect of Zn doping on the hydrogenolysis of glycerol over ZnNiAl catalyst 期刊论文  OAI收割
journal of molecular catalysis a-chemical, 2014, 卷号: 395, 页码: 1-6
Li, Xiaoru; Zhang, Chao; Cheng, Haiyang; He,Limin; Lin,Weiwei; Yu,Yancun; Zhao,Fengyu
收藏  |  浏览/下载：87/0  |  提交时间：2015/10/20
Nickel based catalyst is of interest in the industrial catalytic processes  and it is always modified by doping a second element to improve its catalytic properties. Understanding the role of dopant is extremely helpful in tailoring the active centers. In this work  Zn could induce a significant improvement of the catalytic performance of NiAl for the hydrogenolysis of glycerol. The Zn doped ZnNiAl catalysts exhibited high activity and the improved selectivity to 1  2-propanediol  it was about 2 times higher than the original ones. The ZnNi alloy formed in ZnNiAl was responsible for the noticeable catalytic performance. They preferred to coordinate with the end hydroxyl group of glycerol  promoted the cleavage of C-O bond in glycerol  and resulted in the dominant formation of 1  2-propanediol. The findings described here will provide a useful knowledge for rational design of nickel-based catalysts  as well as reveal a new reaction model for the hydrogenolysis of glycerol. (C) 2014 Elsevier B.V. All rights reserved.  
A Local Image Enhancement Method Based on Adjacent Pixel Gray Order-preserving Principle 会议论文  OAI收割
5th International Symposium on Photoelectronic Detection and Imaging (ISPDI) - Infrared Imaging and Applications, Beijing, June 25-27, 2013
作者:  Fan XP(范晓鹏);  Cai TF(蔡铁峰);  Zhu F(朱枫)
收藏  |  浏览/下载：41/0  |  提交时间：2013/12/26
The paper is committed in local image enhancement. At first, the authors propose an adjacent pixel gray order-preserving principle. Adjacent pixel gray order-preserving principle is the basement of local enhancement method which ensures that there is no distortion in processed image. And then, the authors propose an iterative algorithm, which could stretch gray-scale difference of adjacent pixels in premise of not changing gray magnitude relationship between adjacent pixels. At last, the authors propose a totally reference image quality assessment method based on adjacent pixel gray order-preserving principle. According to this quality assessment method, the authors made a set of comparative experiments with local histogram equalization and method. Experimental results show that the proposed enhancement method can get higher score and provide better visual effects, fully demonstrating its effectiveness. According to this quality assessment method, the proposed method shows a good effectiveness, through experimental results and comparison with local histogram equalization method.  
Lightweight design of large scale theodolite's turntable based on topology optimization of continuum structure (EI CONFERENCE) 会议论文  OAI收割
2012 International Conference on Optoelectronics and Microelectronics, ICOM 2012, August 23, 2012 - August 25, 2012, Changchun, China
作者:  Wang Y.;  Wang Y.;  Wang Y.;  Wang Y.;  Wang Y.
收藏  |  浏览/下载：28/0  |  提交时间：2013/03/25
In order to solve the problem that the weight of large scale theodolite's casting or steel plate welded structure is too heavy  lightweight design of large scale turntable based on topology optimization of continuum structure is investigated. Topology optimization could have better optimization efficiency because it can provide the optimized distribution of material and gain optimized structure in conceptual design phase of the structural design. In order to obtain lightweight and high stiffness structure  a truss turntable based on topology optimization of continuum structure is presented  and the validity of this lightweight structure is examined by finite element analysis. Comparing to the traditional welding steel turntable  the lightweight turntable  without changing the static displacement  can lose 386.48 kg(lightweight ratio is 26.7%)  and its first-order natural frequency raises from 167.02Hz to 173.71Hz. Meanwhile  in other aspects this turntable also has better performance than traditional structure. 2012 IEEE.  
Research on soybean security of China based on system dynamics (EI CONFERENCE) 会议论文  OAI收割
31st Chinese Control Conference, CCC 2012, July 25, 2012 - July 27, 2012, Hefei, China
作者:  Gao M.-H.
收藏  |  浏览/下载：26/0  |  提交时间：2013/03/25