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rhe Mitochondrion-Targeted PENTATRiCOPEPTiDE REPEAT78 Protein is Required for nad5 Mature mRNA Stability and Development in Maize

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Molecular Plant 2017年第10期10卷 1321-1333页

作者： ya-Feng Zhang Masaharu Suzuki Feng sun Bao-Cai Tan Key Laboratory of Plant Cell Engineering and Germplasm innovation Ministry of Education School of Life Sciences Shandong University Jinan 250100 China Guangdong Provincial Key Laboratory of Plant Molecular Breeding College of Agriculture South China Agricultural University Guangzhou 510642 China Plant Molecular and Cellular Biology Program University of Florida Gainesville Florida 32611 USA

Pentatricopepetide repeat （PPR） proteins are a large family of RNA-binding proteins involved in RNA meta- bolism in plant organelles. Although many PPR proteins have been functionally studied, few of them are identified with a function in mitochondrial RNA stability. By using a reverse genetic approach, we characterized the role of the mitochondrion-targeted PPR78 protein in nad5 mature mRNA stability and maize （Zea mays） seed development. Loss of PPR78 function leads to a dramatic reduction in the steady-state level of mitochondrial nad5 mature mRNA, blocks the assembly of complex i in the electron transport chain, and causes an arrest in embryogenesis and endosperm development. Characterization of a second strong allele confirms the function of PPR78 in nad5 mRNA accumulation and maize seed development. The generation of mature nad5 requires the assembly of three distinct precursor RNAs via transsplicing reactions, and the accumulation ofnad5T1 precursor is reduced in the ppr78 mutants. However, it is the instability of mature nad5 rather than nad5T1 causing loss of the full-length nad5 transcript, and degradation of nad5 losing both translation start and stop codons is enriched in the mutant. Our data imply the assembly of mature nad5 mRNA precedes the protection of PPR78.

关键词： PPR nad5 mitochondrial RNA stability complex i seed development maize

Numerical analysis of landslide-generated debris flow on July 3, 2021 in izu Mountain area, Shizuoka County, Japan

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Journal of Mountain Science 2022年第6期19卷 1738-1747页

作者： sun Tong sun Dong-ya WANG Xie-kang MA Qiang GOURBESViLLE Philippe NOHARA Daisuke State Key Laboratory of Hydraulics and Mountain River Engineering Sichuan UniversityChengdu 610065China China institute of Water Resources and Hydropower Research Beijing 100038China Universite Cote d'Azur Nice 06903France Sustainable Society Laboratory KAJiMA Technical Research institute Kyoto University 6110011Japan

With the increasing of extreme rainfall frequency, landslides accompanied by mudslides often lead to serious casualties and property damage. On 3rd July 2021, a debris flow occurred in izu Mountain area, Shizuoka County, Japan, and then resulted in 26 deaths and 131 houses destroyed, where houses were mainly built along the banks of the creek. in order to analyse the landslide state and distribution, a two-dimensional debris flow dynamic model(Massflow) was selected to simulate the process of the landslide-generated debris flow. When the model results are considered together with remote sensing images, the volume distribution of the unstable landslide is also able to be determined. The results show that(1) the affected areas are mainly concentrated at the outfall of the gully and on both sides of the streets.(2) The pore pressure ratio is an important factor affecting the damage range of this debris flow.(3) The increase of the pore pressure ratio in the landslide make the movement distance of debris flow increase significantly.

关键词： izu Mountain Landslide Debris flow Numerical simulation Pore pressure ratio

Bismuth Mediated Organic Reaction: A Convenient Method for the Synthesis of Allylic (Benzylic) Selenides and α-Organylselenocarbonyl Compounds in Aqueous Media

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Chinese Chemical Letters 2000年第12期11卷 1037-1040页

作者： Pei Pei sun ya Ping XiAO Bao Chuan SHi Department of Chemistry Nanjing Normal UniversityNanjing 210097

in the presence of BiCl3/Al or BiCl3/Fe, in THF-H2O, allylic (benzylic) bromides or α-bromoketones react with diorganyl diselenides to give allylic (benzylic) selenides orα-organylselenocarbonyl compounds respective... 详细信息

关键词： Bismuth allylic ( benzylic) selenides,α-organylselenocarbonyl compounds synthesis.

Hexagonal MBenes-Supported Single Atom as Electrocatalysts for the Nitrogen Reduction Reaction

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Energy Material Advances 2023年第1期4卷 331-343页

作者： ya Gao Erpeng Wang yazhuo Zheng Jian Zhou Zhimei sun School of Materials Science and Engineering Beihang UniversityBeijing 100191China

The electrocatalytic nitrogen reduction reaction(NRR)is currently constrained by sluggish reaction kinetics and poor selectivity because of the difficulties in activating inert N≡N triple bonds and the existence of competing hydrogen evolution reaction(HER).Therefore,electrocatalysts with high activity,selectivity,and stability are highly ***,by means of first-principles calculations,we investigated the electrocatalytic NRR performance of a series of transition metal atoms(e.g.,3d,4d,and 5d)embedded in defective hexagonal MBene nanosheets[h-Zr(Hf)_(2)B_(2)O_(2)]and identified that h-Zr(Hf)_(2)B_(2)O_(2) could be an excellent platform for electrocatalytic *** the basis of our proposed screening criteria,16 candidates are efficiently selected out from 50 systems,among which,Zr_(2)B_(2)O_(2)-Cr stands out with high selectivity to NRR against HER and the ultralow limiting potential(−0.10 V).The value is much lower than that of the well-established stepped Ru(0001)surface(−0.43 V).The origin of the high activity toward NRR is attributed to the synergistic effect of the single atom(SA)and the M atoms in the *** impressively,a composition descriptor is further proposed on the basis of the inherent characteristics of the catalysts[number of valence electrons of SA and electronegativity of the SA and Zr(Hf)atoms],which helps to better predict the catalytic *** work not only contributes to the development of highly efficient NRR electrocatalysts but also extend the application of h-MBenes in electrocatalysis.

关键词： selectivity bonds kinetics

Electroacupuncture regulates the stress-injury-repair chain of events after cerebral ischemia/reperfusion injury

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Neural Regeneration Research 2017年第6期12卷 925-930页

作者： Peng Shi Lin-lin sun Yi-shuo Lee ya Tu School of Acupuncture-Moxibustion and Tuina Beijing University of Chinese Medicine

inflammation after stroke is the main cause of cerebral ischemia/reperfusion injury. Cascading events after injury can lead to cell death. Heat shock protein 70 and other endogenous injury-signaling molecules are released by damaged cells, which can lead to systemic stress reactions. Protecting the brain through repair begins with the stress-injury-repair signaling chain. This study aimed to verify whether acupuncture acts through this chain to facilitate effective treatment of ischemic stroke. Rat models of cerebral ischemia/reperfusion injury were established by Zea Longa＇s method, and injury sites were identified by assessing neurological function, 2,3,5-triphenyltetrazolium chloride staining, and hematoxylin-eosin staining. Electroacupuncture at acupoints Baihui（DU20） and Zusanli（ST36） was performed in the model rats with dilatational waves, delivered for 20 minutes a day at 2–100 Hz and an amplitude of 2 m A. We analyzed the blood serum from the rats and found that inflammatory cytokines affected the levels of adrenotrophin and heat shock protein 70, each of which followed a similar bimodal curve. Specifically, electroacupuncture lowered the peak levels of adrenocorticotrophic hormone and heat shock protein 70. Thus, electroacupuncture was able to inhibit excessive stress, reduce inflammation, and promote the repair of neurons, which facilitated healing of ischemic stroke.

关键词： repair acupuncture hematoxylin eosin minutes endogenous Acupuncture neurological inflammation staining

Progress in mechanochromic luminescence of gold(Ⅰ) complexes

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Chinese Chemical Letters 2021年第12期32卷 3718-3732页

作者： Shiqi Cheng Zhao Chen ya Yin Yue sun Shenghua Liu Hubei Key Laboratory of Catalysis and Materials Science College of Chemistry and Material SciencesSouth-Central University for NationalitiesWuhan 430074China Jiangxi Key Laboratory of Organic Chemistry Jiangxi Science and Technology Normal UniversityNanchang 330013China Key Laboratory of Pesticide and Chemical Biology Ministry of EducationCollege of ChemistryCentral China Normal UniversityWuhan 430079China

Photophysical properties of organic and organometallic luminophors are closely related with their molecular packings, enabling the exploitation of stimuli-responsive functional luminescent *** molecules, which can change their luminescence characteristics after mechanical stimulus, have received an increasing interest due to their promising applications in multifunctional sensors and molecular switches. During the past two decades, the development of gold(Ⅰ) chemistry has been attracting the attention of plenty of researchers. indeed, a variety of gold(i) complexes with fascinating photophysical behaviors have been discovered. This review focuses on the research progress in the different types of mechanoluminochromic gold(Ⅰ) complexes, including mono-, bi-and multi-nuclear gold(Ⅰ)systems. Their interesting luminescence behaviors of these gold(Ⅰ)-containing luminogens upon mechanical stimulus and the proposed mechanisms of their observed mechanochromic luminescence are summarized systematacially. Moreover, this review will put forward an outlook about the possible opportunities and challenges in this significative scientific field.

关键词： Gold(Ⅰ)complexes Mechanochromic luminescence Mechanisms Molecular packings Aurophilic interactions

NUMERiCAL STUDiES ON AiRFLOW AND POLLUTANT DiSPERSiON iN URBAN STREET CANYONS FORMED BY SLANTED ROOF BUiLDiNGS

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Journal of Hydrodynamics 2007年第1期19卷 100-106页

作者： HUANG Yuan-dong JiN Ming-xia sun ya-nan School of Civil and Environmental Engineering University of Shanghai for Science and Technology Shanghai 200093 China.

Based on the CFD technique, fifteen cases were evaluated for the airflows and pollutant dispersions inside urban street canyons formed by slanted roof buildings. The simulated wind fields and concentration contours show that W/H, W/h and h/H （where W is the street width, and Hand h are the heights of buildings at the leeward and windward sides of the street, respectively） are the crucial factors in determining the vortex structure and pollutant distribution within a canyon. it is concluded that （1） in a symmetrical canyon, at W/H =0.5 two vortices （an upper clockwise vortex between the slanted roofs and a lower counter-clockwise one） are developed and pollutants accumulate on the windward side of the street, whereas at w/H=2.0 only one clockwise vortex is generated and thus pollution piles up on the leeward side, （2） in a step-up canyon with W/H=0.5 to 2.0 （at h/H =1.5 to 2.0）and a step-down canyon with W/h=1.0 （at h/H =0.5 to 0.667）, the pollution level close to the lower building is higher than that close to the taller building since a clockwise vortex is generated in the step-up canyon and a counter-clockwise one in the step-down canyon, （3） in a narrow step-down canyon with W/h=0.5 （at h/H =0.667） very poor ventilation properties is detected, and inside a wider step-down canyon with W/h=2.0 the vortex structure and consequently pollutant distribution varies greatly with h/H.

关键词： numerical simulation wind flow pollutantdispersion street canyons slanted roof buildings

Tumor Molecular imaging with Nanoparticles

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Engineering 2016年第1期2卷 132-140页

作者： Zhen Cheng Xuefeng ya Xilin sun BaozhongShen Sanjiv Sam Gambhir a Molecular imaging Program at Stanford Department of Radiology Stanford University Stanford CA 94305 USA Molecular imaging Research Center of Harbin Medical University Harbin 150001 China TOF-PET/CT/MR Center the Fourth Hospital of Harbin Medical University Harbin 150001 China ora Umverslty Stanford CA 94305 USA

Molecular imaging(Mi)can provide not only structural images using traditional imaging techniques but also functional and molecular information using many newly emerging imaging *** the past decade,the utilization of nanotechnology in Mi has exhibited many significant advantages and provided new opportunities for the imaging of living *** is expected that multimodality nanoparticles(NPs)can lead to precise assessment of tumor biology and the tumor *** review addresses topics related to engineered NPs and summarizes the recent applications of these nanoconstructs in cancer optical imaging,ultrasound,photoacoustic imaging,magnetic resonance imaging(MRi),and radionuclide *** challenges involved in the translation of NPs to the clinic are discussed.

关键词： Tumor Molecular imaging Nanoparticles

Characterization of new negative temperature coefficient thermistors based on Zn-Ni-O system

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Journal of Advanced Ceramics 2016年第4期5卷 329-336页

作者： Xiang sun Hong ZHANG ya LiU Jia GUO Zhicheng Li School of Materials Science and Engineering Central South University Changsha 410083 China School of Materials Science and Engineering Central South University Changsha 410083 ChinaState Key Laboratory of Powder Metallurgy Central South University Changsha 410083 China

Y2O3-doped Zn1-xNixO (x=0,0.3,0.4,0.5,0.6,0.7,and 0.9) powders were prepared by a wet chemical synthesis method,and the related ceramics were obtained by the traditional ceramic sintering *** phases and related electrical properties of the ceramics were *** analysis of X-ray diffraction (XRD) indicates that the prepared ceramics with Ni substitution have a cubic crystalline *** resistance-temperature feature indicates that all the ceramics show a typical effect of negative temperature coefficient (NTC) of resistivity with the thermal constants between 3998 and 5464 K,and have high cyclical stability in a temperature range from 25 to 300 ℃.The impedance analysis reveals that both grain effect and grain boundary effect contribute collectively to the NTC *** electron hopping and band conduction models are proposed for the grain (bulk) conduction,and the thermally activated charge carrier transport overcoming the energy barrier is suggested for the grain boundary conduction.

关键词： Zn1-xNixO thermistors microstructure electrical properties conduction mechanism