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Woody vegetation of protected areas in northern Togo. Cases of Barkoissi, Galangashi and Oti-Keran: ecological and structure analyses of plant communities

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Forestry Studies in China 2011年第1期13卷 23-35页

作者： Folega FOUSSENI Wala KPERKOUM zhang chun-yu ZHAO Xiu-hai Akpagana KOFFI Key Laboratory for Silviculture and Conservation of Ministry of Education Beijing Forestry University Beijing 100083 P. R. China Universite de Lome Laboratoire de Botanique et Eeologie Vegetale Faculte des Sciences Lome BP 1515 Togo

The 170 samples obtained from ligneous investigation in Barkoissi,Galangashi and Oti-Keran protected areas（northern Togo） were subjected to floristic processing and several multivariate analyses in order to study plant diversity,life form and chorological type distribution and to classify and identify the main plant communities with their demographic ***,the overall life form and phytogeographical type frequencies were calculated to analyze and show the distribution of the 68 plants species in this *** plant communities were determined by using the hierarchical clustering with wards *** plant communities found were identified by the technique of indicator value（IndVal）.For each grouping diversity index such as specific richness,Shannon index and Pielou＇s evenness was set *** canonical correspondence analysis（CCA） was also used to relate the impact of environment factors and the distribution of *** the variance analysis（ANOVA） associated to post-hoc test was used to compare the similarity between the *** these 170 samples,12 plant communities were discriminated,three for the reserve of Barkoissi,three for the reserve of Galangashi and six for the reserve of *** samples were well distributed in the factorial plan form by axe 1 and 3 of *** plant communities were distributed along the moisture gradient in the *** Sudano-Zambesian species followed by Sudanian species were the phytogeographical types most found in these *** microphanerophytes were the most represented life *** structural parameters such as diameter and height means,the basal area and the densities determined and submitted to post-hoc test show some important similarity between some groups *** overall,the vegetation condition of the three protected areas is somehow disturbed while most of the plant communities are *** preliminary ecological data obtained are essential and fundamental for the management an

关键词： diversity phytogeography phytosociology CCA ANOVA Barkoissi Galangashi Oti-Keran

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Regulation of specific abnormal calcium signals in the hippocampal CA1 and primary cortex M1 alleviates the progression of temporal lobe epilepsy

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Neural Regeneration Research 2024年第2期19卷 425-433页

作者： Feng Chen Xi Dong Zhenhuan Wang Tongrui Wu Liangpeng Wei Yuanyuan Li Kai zhang Zengguang Ma chao Tian Jing Li Jingyu Zhao Wei zhang Aili Liu Hui Shen Laboratory of Neurobiology School of Biomedical EngineeringTianjin Medical UniversityTianjinChina Institute for Translational Neuroscience the Second Affiliated Hospital of Nantong UniversityNantongJiangsu ProvinceChina Institute for Translational Brain Research Fudan UniversityShanghaiChina Department of Radiology the Affiliated Drum Tower Hospital of Nanjing University Medical SchoolNanjingJiangsu ProvinceChina Innovative Institute of Chinese Medicine and Pharmacy Shandong University of Traditional Chinese MedicineJinanChina Department of Anesthesiology Tianjin Medical University General HospitalTianjinChina Department of Orthopaedics Tianjin Medical University General HospitalTianjinChina Tianjin Eye Hospital Tianjin Eye InstituteTianjin Key Lab of Ophthalmology and Visual ScienceTianjinChina Laboratory of Neurobiology School of Basic Medical SciencesTianjin Medical UniversityTianjinChina

Temporal lobe epilepsy is a multifactorial neurological dysfunction syndrome that is refractory,resistant to antiepileptic drugs,and has a high recurrence *** pathogenesis of temporal lobe epilepsy is complex and is not fully *** calcium dynamics have been implicated in temporal lobe ***,the effect of fluctuating calcium activity in CA1 pyramidal neurons on temporal lobe epilepsy is unknown,and no longitudinal studies have investigated calcium activity in pyramidal neurons in the hippocampal CA1 and primary motor cortex M1 of freely moving *** this study,we used a multichannel fiber photometry system to continuously record calcium signals in CA1 and M1 during the temporal lobe epilepsy *** found that calcium signals varied according to the grade of temporal lobe epilepsy *** particular,cortical spreading depression,which has recently been frequently used to represent the continuously and substantially increased calcium signals,was found to correspond to complex and severe behavioral characteristics of temporal lobe epilepsy ranging from gradeⅡto gradeⅤ.However,vigorous calcium oscillations and highly synchronized calcium signals in CA1 and M1 were strongly related to convulsive motor *** inhibition of pyramidal neurons in CA1 significantly attenuated the amplitudes of the calcium signals corresponding to gradeⅠ*** addition,the latency of cortical spreading depression was prolonged,and the above-mentioned abnormal calcium signals in CA1 and M1 were also significantly ***,it was possible to rescue the altered intracellular calcium *** simultaneous analysis of calcium signals and epileptic behaviors,we found that the progression of temporal lobe epilepsy was alleviated when specific calcium signals were reduced,and that the end-point behaviors of temporal lobe epilepsy were *** results indicate that the calcium dynamic between CA1 and M1 may reflect sp

关键词： Ca^(2+) calcium signals chemogenetic methods hippocampus primary motor cortex pyramidal neurons temporal lobe epilepsy

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Microstructure and mechanical properties of complex-shaped 7075 aluminium alloy prepared using modified polyoxymethylene-based feedstock

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Transactions of Nonferrous Metals Society of China 2024年第12期34卷 3862-3875页

作者： Heng ZOU Meng-xiong CHEN Yang FU Hui-wen XIONG Lei zhang Ke-chao ZHOU State Key Laboratory of Powder Metallurgy Central South UniversityChangsha 410083China

Additives of dioctyl phthalate(DOP),ethylene bis-stearomide(EBS),and epoxy(EP)were selected to modify the surface of 7075 Al alloy *** groups in DOP and EBS form hydrogen bonds with hydroxyl groups on the surface of Al ***,the epoxy groups in the epoxy resin undergo ring-opening reactions with hydroxyl *** above interactions increased the compatibility between alloy powder and polyoxymethylene(POM).After sintering,samples containing DOP and EP presented high contents of C and O,while the part with EBS additive exhibited the lowest contents of 0.006 wt.%C and 0.604 wt.%O,*** C tends to accumulate at grain boundaries during ***,excessive O causes secondary oxidation of aluminium alloy powder,inhibiting the sintering densification ***,the densities of the samples containing DOP and EP were only 85.52%and 79.01%,*** contrast,using EBS as an additive,high-quality aluminium alloy parts were achieved,with a relative density of 97.64%and a tensile strength of 193 MPa.

关键词： 7075 aluminium alloy polyoxymethylene-based feedstock additives compression moulding metal injection moulding microstructure mechanical properties

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Off-on-off luminescent switching of a dye containing imidazo[4,5-f][1,10]phenanthroline

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Chinese Chemical Letters 2011年第6期22卷 647-650页

作者： Hai Guang zhang Xu Tang Tao Kao Shan Chen chun Xue Yuan Shi Na Yan Min Hua Jiang College of Chemistry Science Qufu Normal UniversityQufu 273165China State Key Laboratory of Crystal Materials Shandong UniversityJinan 250100China School of Life Science Shandong UniversityJinan 250100China

A new acid-base fluorescent switch containing both imidazo[4,5-f][1,10]-phenanthroline and triphenylamine groups has been *** fluorescence emissions and absorptions can be reversibiy changed through protonation/deprotonation of imidazole and amine moiety by controlling the intramolecular charge transfer（ICT） process,leading to off-on-off fluorescent molecular switching.

关键词： Fluorescence switch Imidazo[4 5-f][1 10]phenanthroline Triphenylamine Intramolecular charge transfer(ICT)

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Mechanical properties and thermal shock resistance of tungsten alloys strengthened by laser fragmentation-processed zirconium carbide nanoparticles

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Tungsten 2020年第4期2卷 381-389页

作者： Ke Jing chao zhang Rui Liu Zhuo‑Ming Xie Lin‑chao zhang Li‑Feng zhang Jun Liu Rui Gao Jun‑Feng Yang Xian‑Ping Wang Ting Hao Xue‑Bang Wu Qian‑Feng Fang Chang‑Hao Liang Guang‑Nan Luo You‑Yun Lian Xiang Liu Chang‑Song Liu Key Laboratory of Materials Physics Institute of Solid State PhysicsHFIPSChinese Academy of SciencesHefei 230031China University of Science and Technology of China Hefei 230026China Institute of Plasma Physics Chinese Academy of SciencesHefei 230031China Southwestern Institute of Physics Chengdu 610041China

Zirconium carbide(ZrC)nanoparticles with an average size of 5.6 nm were synthesized through laser fragmentation(LF)from as-received 20-60 nm ZrC particles,and LF-ZrC nanoparticle dispersion-strengthened tungsten(LF-WZC)samples were fabricated by spark plasma sintering *** average grain size of LF-WZC is 1.91μm and most ZrC particles in LF-WZC are smaller than 10 ***-WZC exhibits finer grain size,higher yield strength and hardness but lower ductility as compared with W-ZrC samples using as-received ZrC(WZC).The results showed that finer ZrC nanoparticles dispersed in tungsten can enhance the strength by hindering the motion of dislocations,but they may also introduce stress concentra-tion and thus reduce the *** thermal shock resistance of the WZC and LF-WZC samples was investigated using an electron beam *** LF-WZC sample also exhibits a higher cracking threshold(0.33-0.44 GW·m^(−2))than WZC(0.22-0.33 GW·m^(−2))at room *** enhanced thermal shock resistance of LF-WZC could be attributed to its high yield strength.

关键词： Tungsten Mechanical properties ZrC Laser fragmentation Thermal shock resistance

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Late sowing enhances lodging resistance of wheat plants by improving the biosynthesis and accumulation of lignin and cellulose

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Journal of Integrative Agriculture 2023年第5期22卷 1351-1365页

作者： DONG Xiu-chun QIAN Tai-feng CHU Jin-peng zhang Xiu LIU Yun-jing DAI Xing-long HE Ming-rong State Key Laboratory of Crop Biology Ministry of Science and Technology/Key Laboratory of Crop Ecophysiology and Farming SystemMinistry of Agriculture and Rural Affairs/Agronomy CollegeShandong Agricultural UniversityTai’an 271018P.R.China Jining Agricultural Technology Extension Center Jining 272113P.R.China

Delayed sowing mitigates lodging in wheat. However, the mechanism underlying the enhanced lodging resistance in wheat has yet to be fully elucidated. Field experiments were conducted to investigate the effects of sowing date on lignin and cellulose metabolism, stem morphological characteristics, lodging resistance, and grain yield. Seeds of Tainong 18,a winter wheat variety, were sown on October 8(normal sowing) and October 22(late sowing) during both of the 2015–2016 and 2016–2017 growing seasons. The results showed that late sowing enhanced the lodging resistance of wheat by improving the biosynthesis and accumulation of lignin and cellulose. Under late sowing, the expression levels of key genes(Ta PAL, Ta CCR, Ta COMT, TaCAD, and TaCesA1, 3, 4, 7, and 8) and enzyme activities(TaPAL and TaCAD) related to lignin and cellulose biosynthesis peaked 4–12 days earlier, and except for the TaPAL, TaCCR, and TaCesA1 genes and TaPAL, in most cases they were significantly higher than under normal sowing. As a result, lignin and cellulose accumulated quickly during the stem elongation stage. The mean and maximum accumulation rates of lignin and cellulose increased, the maximum accumulation contents of lignin and cellulose were higher, and the cellulose accumulation duration was prolonged. Consequently, the lignin/cellulose ratio and lignin content were increased from 0 day and the cellulose content was increased from 11 days after jointing onward. Our main finding is that the improved biosynthesis and accumulation of lignin and cellulose were responsible for increasing the stem-filling degree, breaking strength, and lodging resistance. The major functional genes enhancing lodging resistance in wheat that are induced by delayed sowing need to be determined.

关键词： cellulose late sowing lignin lodging resistance wheat

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Assessment of the contribution percentage of inherent soil productivity of cultivated land in China

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Journal of Integrative Agriculture 2019年第11期18卷 2619-2627页

作者： WANG Shi-chao WANG Jin-zhou ZHAO Ya-wen REN Yi XU Ming-gang zhang Shu-xiang LU Chang-ai National Engineering Laboratory of Farmland Cultivation Technology/Institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural SciencesBeijing 100081P.R.China The National Agro-Tech Extension and Service Center Beijing 100125P.R.China

The contribution percentage of inherent soil productivity(CPISP)refers to the ratio of crop yields under no-fertilization versus under conventional fertilization with the same field *** is a comprehensive measure of soil *** study used 1086 on-farm trials(from 1984-2013)and 27 long-term field experiments(from 1979-2013)to quantify changes in ***,we present CPISP3 values,which reflect the CPISP states during the first three years after site establishment,for a series of sites at different locations in China collected in 1984-1990(the 1980s),1996-2000(the 1990s),and 2004-2013(the 2000s).The results showed that the average CPISP3 value for three crops(wheat,rice,and maize)was 53.8%.Historically,the CPISP3 in the 1990s(57.5%)was much higher than those in the 1980s(50.3%),and the 2000s(52.0%)(P≤0.05).Long-term no-fertilization caused CPISP levels to gradually decline and then stabilize;for example,in a mono-cropping system with irrigation,the CPISP values in Northwest and Northeast China declined by 4.5 and 4.0%,respectively,each year for the first ten years,but subsequently,the CPISP values *** contrast,the CPISP for upland crops in double-cropping systems continued to decrease at a rate of 1.1%per *** CPISP for upland-paddy cropping decreased very slowly(0.07%per year),whereas the CPISP for paddy cropping decreased sharply(3.1%per year,on average)for the first two years and then remained steady during the following ***,upland crops in double-cropping systems consume the most inherent soil productivity,whereas paddy fields are favourable for maintaining a high level of ***,our results demonstrate a need to further improve China’s CPISP3 values to meet growing productivity demands.

关键词： crop yield inherent soil productivity typical cropping system planting years cropspecies

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RGDC Peptide Modified Quantum Dots Labelling and Imaging of Tumor Cells

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Chemical Research in Chinese Universities 2011年第5期27卷 832-835页

作者： GUO Yi LI chun-rong SHEN Huai-bin zhang Xue-zhong LI Lin-song YU Qian XU Li Key Laboratory for Molecular Enzymology and Engineering Ministry of Education College of Life Science Jilin University Changchun 130012 P. R. China Department of Drug Administration China-Japan Union Hospital of Jilin University Changchun 130033 P. R. China Key Laboratory for Special Functional Materials Ministry of Education Henan University Kaifeng 475004 P. R. China

The labelling and imaging of tumor cells were investigated via arginine-glycine-aspartic acidcysteine（RGDC） peptide-labelled quantum dots（QDs）. The results show that RGDC modified QDs can label SMMC-7721 tumor cells and adhere to cellular membrane. In constrast, the unmodified QDs are mainly dispersed around the cell. We also found that the RGDC-QDs can penetrate into the cell at 2 h of incubation. After 6 h of incubation, RGDC-QDs can accumulate in a unique intracellular region.

关键词： Arginine-glycine-aspartic acid-cysteine(RGDC) peptide Quantum dot Fluorescence labelling

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Two central circadian oscillators OsPRR59 and OsPRR95 modulate magnesium homeostasis and carbon fixation in rice

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Molecular Plant 2022年第10期15卷 1602-1614页

作者： chun-Qu Chen Xin-Yue Tian Jian Li Shuang Bai Zhuo-Yan zhang Yuan Li Hong-Rui Cao Zhi-Chang Chen Root Biology Center Fujian Agriculture and Forestry UniversityFuzhou 350002China College of Biological and Environmental Engineering Binzhou UniversityBinzhou 256603China

Photosynthesis,which provides oxygen and energy for all living organisms,is circadian ***-associated metabolism must tightly coordinate with the circadian clock to maximize the efficiency of the light-energy capture and carbon ***,the molecular basis for the interplay of photosynthesis and the circadian clock is not fully understood,particularly in crop ***,we report two central oscillator genes of circadian clock,OsPRR95 and OsPRR59 in rice,which function as transcriptional repressors to negatively regulate the rhythmic expression of OsMGT3 encoding a chloroplast-localized Mg2+***3-dependent rhythmic Mg fluctuations modulate carbon fixation and consequent sugar output in rice ***,sugar triggers the increase of superoxide,which may act as a feedback signal to positively regulate the expression of OsPRR95 and *** together,our results reveal a negative-feedback loop that strengthens the crosstalk between photosynthetic carbon fixation and the circadian clock,which may improve plan adaptation and performance in fluctuating environments.

关键词： OsPRR OsMGT3 photosynthesis magnesium rice

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Phosphorylation of Cofilin-1 Enhances Paclitaxel Resistance of Epithelial Ovarian Cancer Cells by Inhibiting Apoptosis

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Biomedical and Environmental Sciences 2021年第6期34卷 465-477页

作者： LI Min DONG Xu Dong LYU Qiu Bo zhang Wei HUANG Shuai YANG chun Xue CUI Di LAI Hui Ying Department of Obstetrics and Gynecology Beijing Hospital National Center of GerontologyInstitute of Geriatric MedicineChinese Academy of Medical SciencesBeijing 100730China Department of Obstetrics the First People's Hospital of Yunnan ProvinceKunming 650032YunnanChina Department of Pathology Beijing HospitalNational Center of GerontologyInstitute of Geriatric MedicineChinese Academy of Medical SciencesBeijing 100730China Peking University Health Science Center Beijing 100069China Clinical Laboratory Beijing HospitalNational Center of GerontologyInstitute of Geriatric MedicineChinese Academy of Medical SciencesBeijing 100730China

Objective To investigate the molecular mechanism of high phosphorylation levels of cofilin-1(p-CFL-1)associated with paclitaxel resistance in epithelial ovarian cancer(EOC)*** Cells displaying varying levels of p-CFL-1 and CFL-1 were created by plasmid transfection and shRNA *** inhibition rate indicating paclitaxel efficacy was assessed by Cell Counting Kit-8(CCK-8)*** was assessed by flow cytometry and protein levels were detected by western *** real-time polymerase chain reaction(qRT-PCR)was used to measure the expression levels of phosphokinases and phosphatases of *** analysis evaluated the correlation between the prognosis of EOC patients and the levels of p-CFL-1 and slingshot-1(SSH-1).Results High levels of p-CFL-1 were observed in EOC cells that survived treatment with high doses of ***3 cell mutants with upregulated p-CFL-1 showed impaired paclitaxel efficacy,as well as decreased apoptosis rates and pro-survival patterns of apoptosis-specific protein *** accumulation of p-CFL-1 inhibited paclitaxel-induced mitochondrial ***-1 silencing mediated CFL-1 phosphorylation in paclitaxel-resistant SKOV3 ***,the high level of p-CFL-1 and the low level of SSH-1 in EOC tissues were closely related to chemotherapy resistance and poor prognosis in EOC *** The SSH-1/p-CFL-1 signaling pathway mediates paclitaxel resistance by apoptosis inhibition in EOC and is expected to be a potential prognostic predictor.

关键词： Cofilin-1 Slingshot-1 Epithelial ovarian cancer Chemo-resistance Apoptosis

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