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Genetic diversity of the S-type small subunit ribosomal RNA gene of Plasmodium knowlesi isolates from Sabah,Malaysian Borneo and Peninsular Malaysia
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作者 Eric Tzyy Jiann Chong Joveen Wan Fen Neoh +3 位作者 Tiek Ying Lau Kek Heng Chua Yvonne Ai-Lian Lim Ping-Chin Lee 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2024年第2期84-90,共7页
Objective:To determine the genetic diversity of Plasmodium(P.)knowlesi isolates from Sabah,Malaysian Borneo and Peninsular Malaysia,targeting the S-type SSU rRNA gene and including aspects of natural selection and hap... Objective:To determine the genetic diversity of Plasmodium(P.)knowlesi isolates from Sabah,Malaysian Borneo and Peninsular Malaysia,targeting the S-type SSU rRNA gene and including aspects of natural selection and haplotype.Methods:Thirty-nine blood samples infected with P.knowlesi were collected in Sabah,Malaysian Borneo and Peninsular Malaysia.The S-type SSU rRNA gene was amplified using polymerase chain reaction,cloned into a vector,and sequenced.The natural selection and haplotype of the S-type SSU rRNA gene sequences were determined using DnaSP v6 and illustrated using NETWORK v10.This study's 39 S-type SSU rRNA sequences and eight sequences from the Genbank database were subjected to phylogenetic analysis using MEGA 11.Results:Overall,the phylogenetic analysis showed no evidence of a geographical cluster of P.knowlesi isolates from different areas in Malaysia based on the S-type SSU rRNA gene sequences.The S-type SSU rRNA gene sequences were relatively conserved and with a purifying effect.Haplotype sharing of the S-type SSU rRNA gene was observed between the P.knowlesi isolates in Sabah,Malaysian Borneo,but not between Sabah,Malaysian Borneo and Peninsular Malaysia.Conclusions:This study suggests that the S-type SSU rRNA gene of P.knowlesi isolates in Sabah,Malaysian Borneo,and Peninsular Malaysia has fewer polymorphic sites,representing the conservation of the gene.These features make the S-type SSU rRNA gene suitable for comparative studies,such as determining the evolutionary relationships and common ancestry among P.knowlesi species. 展开更多
关键词 Plasmodium knowlesi S-type small subunit ribosomal RNA Genetic diversity Natural selection HAPLOTYPE
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Effect of Co on Solidification Characteristics and Microstructural Transformation of Non-equilibrium Solidified Cu-Ni Alloys
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作者 安红恩 Bih-Lii Chua +1 位作者 Ismail Saad Willey Yun Hsien Liew 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第2期444-453,共10页
Non-equilibrium solidification structures of Cu55Ni45 and Cu55Ni43Co2 alloys were prepared by the molten glass purification cycle superheating method.The variation of the recalescence phenomenon with the degree of und... Non-equilibrium solidification structures of Cu55Ni45 and Cu55Ni43Co2 alloys were prepared by the molten glass purification cycle superheating method.The variation of the recalescence phenomenon with the degree of undercooling in the rapid solidification process was investigated using an infrared thermometer.The addition of the Co element affected the evolution of the recalescence phenomenon in Cu-Ni alloys.The images of the solid-liquid interface migration during the rapid solidification of supercooled melts were captured by using a high-speed camera.The solidification rate of Cu-Ni alloys,with the addition of Co elements,was explored.Finally,the grain refinement structure with low supercooling was characterised using electron backscatter diffraction(EBSD).The effect of Co on the microstructural evolution during nonequilibrium solidification of Cu-Ni alloys under conditions of small supercooling is investigated by comparing the microstructures of Cu55Ni45 and Cu55Ni43Co2 alloys.The experimental results show that the addition of a small amount of Co weakens the recalescence behaviour of the Cu55Ni45 alloy and significantly reduces the thermal strain in the rapid solidification phase.In the rapid solidification phase,the thermal strain is greatly reduced,and there is a significant increase in the characteristic undercooling degree.Furthermore,the addition of Co and the reduction of Cu not only result in a lower solidification rate of the alloy,but also contribute to the homogenisation of the grain size. 展开更多
关键词 non-equilibrium solidification recalescence effect solidification character microstructure
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Rational manipulation of electrolyte to induce homogeneous SEI on hard carbon anode for sodium-ion battery
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作者 Lu Liu Lingling Xiao +4 位作者 Zhi Sun Shahid Bashir Ramesh Kasi Yonghong Gu Ramesh Subramaniam 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第7期414-429,共16页
Sodium-ion batteries (SIBs) have great potential to be the next major energy storage devices due to their obvious advantages and developing advanced electrodes and electrolytes is urgently necessary to promote its fut... Sodium-ion batteries (SIBs) have great potential to be the next major energy storage devices due to their obvious advantages and developing advanced electrodes and electrolytes is urgently necessary to promote its future industrialization.However,hard carbon as a state-of-the-art anode of SIBs still suffers from the low initial Coulomb efficiency and unsatisfactory rate capability,which could be improved by forming desirable solid electrolyte interphases (SEI) to some extent.Indeed,the chemistry and morphology of these interfacial layers are fundamental parameters affecting the overall battery operation,and optimizing the electrolyte to dictate the quality of SEI on hard carbon is a key strategy.Hence,this review summarizes the recent research on SEI design by electrolyte manipulation from solvents,salts,and additives.It also presents some potential mechanisms of SEI formation in various electrolyte systems.Besides,the current advanced characterization techniques for electrolyte and SEI structure analyses have been comprehensively discussed.Lastly,current challenges and future perspectives of SEI formation on hard carbon anode for SIBs are provided from the viewpoints of its compositions,evolution processes,structures,and characterization techniques,which will promote SEI efficient manipulation and improve the performance of hard carbon,and further contribute to the development of SIBs. 展开更多
关键词 SEI Electrolyte optimization Hard carbon Electrochemical performance Sodium-ion batteries
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Surplus energy utilization of spent lithium-ion batteries for high-profit organolithiums 被引量:1
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作者 Jian Lu Yun Zhao +11 位作者 Yuqiong Kang Chenglei Li Yawen Liu Liguang Wang Hao Du Meicen Fan Yunan Zhou John Wozny Tao Li Naser Tavajohi Feiyu Kang Baohua Li 《Carbon Energy》 SCIE CSCD 2023年第6期11-20,共10页
It is challenging to efficiently and economically recycle many lithium-ion batteries(LIBs)because of the low valuation of commodity metals and materials,such as LiFePO_(4).There are millions of tons of spent LIBs wher... It is challenging to efficiently and economically recycle many lithium-ion batteries(LIBs)because of the low valuation of commodity metals and materials,such as LiFePO_(4).There are millions of tons of spent LIBs where the barrier to recycling is economical,and to make recycling more feasible,it is required that the value of the processed recycled material exceeds the value of raw commodity materials.The presented research illustrates improved profitability and economics for recycling spent LIBs by utilizing the surplus energy in lithiated graphite to drive the preparation of organolithiums to add value to the recycled lithium materials.This study methodology demonstrates that the surplus energy of lithiated graphite obtained from spent LIBs can be utilized to prepare high-value organolithiums,thereby significantly improving the economic profitability of LIB recycling.Organolithiums(R-O-Li and R-Li)were prepared using alkyl alcohol(R-OH)and alkyl bromide(R-Br)as substrates,where R includes varying hindered alkyl hydrocarbons.The organolithiums extracted from per kilogram of recycled LIBs can increase the economic value between$29.5 and$226.5 kg^(−1) cell.The value of the organolithiums is at least 5.4 times the total theoretical value of spent materials,improving the profitability of recycling LIBs over traditional pyrometallurgical($0.86 kg^(−1) cell),hydrometallurgical($1.00 kg^(−1) cell),and physical direct recycling methods($5.40 kg^(−1) cell). 展开更多
关键词 lithiated graphite lithium-ion batteries RECYCLING REGENERATION spent lithium-ion batteries
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Non-solvating fluorosulfonyl carboxylate enables temperature-tolerant lithium metal batteries
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作者 Xianshu Wang Junru Wu +8 位作者 Yun Zhao Bin Li Naser Tavajohi Qi Liu Jianguo Duan Ding Wang Peng Dong Yingjie Zhang Baohua Li 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第7期287-295,I0007,共10页
Advanced electrolyte engineering is an important strategy for developing high-efficacy lithium(Li)metal batteries(LMBs).Unfortunately,the current electrolytes limit the scope for creating batteries that perform well o... Advanced electrolyte engineering is an important strategy for developing high-efficacy lithium(Li)metal batteries(LMBs).Unfortunately,the current electrolytes limit the scope for creating batteries that perform well over temperature ranges.Here,we present a new electrolyte design that uses fluorosulfonyl carboxylate as a non-solvating solvent to form difluoroxalate borate(DFOB-)anion-rich solvation sheath,to realize high-performance working of temperature-tolerant LMBs.With this optimized electrolyte,favorable SEI and CEI chemistries on Li metal anode and nickel-rich cathode are achieved,respectively,leading to fast Li^(+)transfer kinetics,dendrite-free Li deposition and suppressed electrolyte deterioration.Therefore,Li||LiNi_(0.80)Co_(0.15)Al_(0.05)O_(2)batteries with a thin Li foil(50μm)show a long-term cycling lifespan over 400 cycles at 1C and a superior capacity retention of 90%after 200 cycles at 0.5C under 25℃.Moreover,this electrolyte extends the operating temperature from-10 to 30℃and significantly improve the capacity retention and Coulombic efficiency of batteries are improved at high temperature(60℃).Fluorosulfonyl carboxylates thus have considerable potential for use in high-performance and allweather LMBs,which broadens the new exploring of electrolyte design. 展开更多
关键词 Lithium metal batteries Methyl fluorosulfonyldifluoroacetate Non-solvating Anion-rich solvation Temperature tolerance
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A Fourth-Order Unstructured NURBS-Enhanced Finite Volume WENO Scheme for Steady Euler Equations in Curved Geometries
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作者 Xucheng Meng Yaguang Gu Guanghui Hu 《Communications on Applied Mathematics and Computation》 2023年第1期315-342,共28页
In Li and Ren(Int.J.Numer.Methods Fluids 70:742–763,2012),a high-order k-exact WENO finite volume scheme based on secondary reconstructions was proposed to solve the two-dimensional time-dependent Euler equations in ... In Li and Ren(Int.J.Numer.Methods Fluids 70:742–763,2012),a high-order k-exact WENO finite volume scheme based on secondary reconstructions was proposed to solve the two-dimensional time-dependent Euler equations in a polygonal domain,in which the high-order numerical accuracy and the oscillations-free property can be achieved.In this paper,the method is extended to solve steady state problems imposed in a curved physical domain.The numerical framework consists of a Newton type finite volume method to linearize the nonlinear governing equations,and a geometrical multigrid method to solve the derived linear system.To achieve high-order non-oscillatory numerical solutions,the classical k-exact reconstruction with k=3 and the efficient secondary reconstructions are used to perform the WENO reconstruction for the conservative variables.The non-uniform rational B-splines(NURBS)curve is used to provide an exact or a high-order representation of the curved wall boundary.Furthermore,an enlarged reconstruction patch is constructed for every element of mesh to significantly improve the convergence to steady state.A variety of numerical examples are presented to show the effectiveness and robustness of the proposed method. 展开更多
关键词 Steady Euler equations Curved boundary NURBS-enhanced finite volume method WENO reconstruction Secondary reconstruction
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Multifractal estimation of NMR T_(2) cut-off value in low-permeability rocks considering spectrum kurtosis: SMOTE-based oversampling integrated with machine learning
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作者 Xiao-Jun Chen Rui-Xue Zhang +4 位作者 Xiao-Bo Zhao Jun-Wei Yang Zhang-Jian Lan Cheng-Fei Luo Jian-Chao Cai 《Petroleum Science》 SCIE EI CAS CSCD 2023年第6期3411-3427,共17页
The transverse relaxation time (T_(2)) cut-off value plays a crucial role in nuclear magnetic resonance for identifying movable and immovable boundaries, evaluating permeability, and determining fluid saturation in pe... The transverse relaxation time (T_(2)) cut-off value plays a crucial role in nuclear magnetic resonance for identifying movable and immovable boundaries, evaluating permeability, and determining fluid saturation in petrophysical characterization of petroleum reservoirs. This study focuses on the systematic analysis of T_(2) spectra and T_(2) cut-off values in low-permeability reservoir rocks. Analysis of 36 low-permeability cores revealed a wide distribution of T_(2) cut-off values, ranging from 7 to 50 ms. Additionally, the T_(2) spectra exhibited multimodal characteristics, predominantly displaying unimodal and bimodal morphologies, with a few trimodal morphologies, which are inherently influenced by different pore types. Fractal characteristics of pore structure in fully water-saturated cores were captured through the T_(2) spectra, which were calculated using generalized fractal and multifractal theories. To augment the limited dataset of 36 cores, the synthetic minority oversampling technique was employed. Models for evaluating the T_(2) cut-off value were separately developed based on the classified T_(2) spectra, considering the number of peaks, and utilizing generalized fractal dimensions at the weight <0 and the singular intensity range. The underlying mechanism is that the singular intensity and generalized fractal dimensions at the weight <0 can detect the T_(2) spectral shift. However, the T_(2) spectral shift has negligible effects on multifractal spectrum function difference and generalized fractal dimensions at the weight >0. The primary objective of this work is to gain insights into the relationship between the kurtosis of the T_(2) spectrum and pore types, as well as to predict the T_(2) cut-off value of low-permeability rocks using machine learning and data augmentation techniques. 展开更多
关键词 Nuclear magnetic resonance Low-permeability porous media T_(2)cut-off value Fractal and multifractal Data augmentation Machine learning
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Phosphorus-doped lithium- and manganese-rich layered oxide cathode material for fast charging lithium-ion batteries
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作者 Yuqiong Kang Xingang Guo +8 位作者 Zhiwu Guo Jiangang Li Yunan Zhou Zheng Liang Cuiping Han Xiangming He Yun Zhao Naser Tavajohi Baohua Li 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2021年第11期538-545,I0012,共9页
Owing to their high theoretical specific capacity and low cost, lithium- and manganese-rich layered oxide (LMR) cathode materials are receiving increasing attention for application in lithium-ion batteries. However, p... Owing to their high theoretical specific capacity and low cost, lithium- and manganese-rich layered oxide (LMR) cathode materials are receiving increasing attention for application in lithium-ion batteries. However, poor lithium ion and electron transport kinetics plus side effects of anion and cation redox reactions hamper power performance and stability of the LMRs. In this study, LMR Li_(1.2)Mn_(0.6)Ni_(0.2)O_(2) was modified by phosphorus (P)-doping to increase Li+ conductivity in the bulk material. This was achieved by increasing the interlayer spacing of the lithium layer, electron transport and structural stability, resulting in improvement of the rate and safety performance. P^(5+) doping increased the distance between the (003) crystal planes from ~0.474 nm to 0.488 nm and enhanced the structural stability by forming strong covalent bonds with oxygen atoms, resulting in an improved rate performance (capacity retention from 38% to 50% at 0.05 C to 5 C) and thermal stability (50% heat release compared with pristine material). First-principles calculations showed the P-doping makes the transfer of excited electrons from the valence band to conduction band easier and P can form a strong covalent bond helping to stabilize material structure. Furthermore, the solid-state electrolyte modified P5+ doped LMR showed an improved cycle performance for up to 200 cycles with capacity retention of 90.5% and enhanced initial coulombic efficiency from 68.5% (pristine) or 81.7% (P-doped LMR) to 88.7%. 展开更多
关键词 Lithium-ion battery Lithium-and manganese-rich layered oxide Phosphorus doping High-rate performance
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3-(Tetrazol-5-yl)-2-imino-coumarins Derivatives: Synthesis, Characterization, and Evaluation on Tumor Cell Lines
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作者 Ali Bouattour Mehdi Fakhfakh +6 位作者 Souhir Abid El-Gharbi Majdi Abid Ludovic Paquin Rémy Le Guevel Thierry Charlier Houcine Ammar Jean-Pierre Bazureau 《International Journal of Organic Chemistry》 CAS 2021年第1期24-34,共11页
The first report of new 3-(tetrazol-5-yl)-2-iminocoumarin derivatives is described. The title compounds were prepared in two steps and were obtained in good yields (55-93%). They have been fully characterized by <s... The first report of new 3-(tetrazol-5-yl)-2-iminocoumarin derivatives is described. The title compounds were prepared in two steps and were obtained in good yields (55-93%). They have been fully characterized by <sup>1</sup>H, <sup>13</sup>C NMR, FTIR, UV-Visible and HRMS. They were tested for their antiproliferative activities against six representative human tumor cell lines (Huh 7-D12, Caco2, MDA-MB231, HCT 116, PC3 and NCI-H727) and HaCat keratinocytes. Among them, compound 5e was active on HCT 116 (IC<sub>50</sub> 15 μM). 展开更多
关键词 2-Iminocoumarin TETRAZOLE Fluorescence Tumor Cell Lines HCT 116
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A review of lithium-ion battery safety concerns:The issues,strategies,and testing standards 被引量:41
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作者 Yuqing Chen Yuqiong Kang +8 位作者 Yun Zhao Li Wang Jilei Liu Yanxi Li Zheng Liang Xiangming He Xing Li Naser Tavajohi Baohua Li 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2021年第8期83-99,I0003,共18页
Efficient and reliable energy storage systems are crucial for our modern society.Lithium-ion batteries(LIBs)with excellent performance are widely used in portable electronics and electric vehicles(EVs),but frequent fi... Efficient and reliable energy storage systems are crucial for our modern society.Lithium-ion batteries(LIBs)with excellent performance are widely used in portable electronics and electric vehicles(EVs),but frequent fires and explosions limit their further and more widespread applications.This review summarizes aspects of LIB safety and discusses the related issues,strategies,and testing standards.Specifically,it begins with a brief introduction to LIB working principles and cell structures,and then provides an overview of the notorious thermal runaway,with an emphasis on the effects of mechanical,electrical,and thermal abuse.The following sections examine strategies for improving cell safety,including approaches through cell chemistry,cooling,and balancing,afterwards describing current safety standards and corresponding tests.The review concludes with insights into potential future developments and the prospects for safer LIBs. 展开更多
关键词 Lithium-ion batteries STANDARDS Safety Thermal abuse Mechanical abuse Electrical abuse
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Optimized model-based control of main mine ventilation air flows with minimized energy consumption 被引量:4
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作者 S.Sjostrom E.Klintenas +1 位作者 P.Johansson J.Nyqvist 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2020年第4期533-539,共7页
In early 2018,the Boliden Garpenberg operation implemented an optimized control strategy as an addition to the existing ventilation on demand system.The purpose of the strategy is to further minimize energy use for ma... In early 2018,the Boliden Garpenberg operation implemented an optimized control strategy as an addition to the existing ventilation on demand system.The purpose of the strategy is to further minimize energy use for main and booster fans,whilst also fulfilling airflow setpoints without violating constraints such as min/max differential pressure over fans and interaction of air between areas in mines.Using air flow measurements and a dynamical model of the ventilation system,a mine-wide coordination control of fans can be carried out.The numerical model is data driven and derived from historical operational data or step changes experiments.This makes both initial deployment and lifetime model maintenance,as the mine evolves,a comparably easy operation.The control has been proven to operate in a stable manner over long periods without having to re-calibrate the model.Results prove a 40%decrease in energy use for the fans involved and a greater controllability of air flow.Moreover,a 15%decrease of the total air flow into the mine will give additional proportional heating savings during winter periods.All in all,the multivariable controller shows a correlation between production in the mine and the ventilation system performance superior to all of its predecessors. 展开更多
关键词 Mine ventilation Ventilation on demand Optimized model-based control Minimized energy consumption Advanced process control
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Efficacy of Long-term Selenium Supplementation in the Treatment of Chronic Keshan Disease with Congestive Heart Failure 被引量:4
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作者 Yan-he ZHU Xin-feng WANG +6 位作者 Guang YANG Jin WEI Wu-hong TAN Li-xin WANG Xiong GUO Mikko J.Lammi Jie-hua XU 《Current Medical Science》 SCIE CAS 2019年第2期237-242,共6页
Few effective treatments for chronic Keshan disease have been available till now.The efficacy of long-term selenium supplementation in the treatment of chronic Keshan disease with congestive heart failure is inconclus... Few effective treatments for chronic Keshan disease have been available till now.The efficacy of long-term selenium supplementation in the treatment of chronic Keshan disease with congestive heart failure is inconclusive.This study aimed to determine whether selenium supplementation is associated with a decreased risk of cardiac death in chronic Keshan disease with congestive heart failure by ten years of follow-up.A retrospective long-term follow-up analysis was performed on a monitored cohort consisting of 302 chronic Keshan disease patients with a mean age of 40.8±11.4 years.Of the 302 chronic Keshan disease patients,170(56.3%)were given selenium supplementation until the end point of follow-up.Cox proportional hazards regression models were used to identify the independent predictors of cardiac events.Our results showed that during the follow-up,there were 101 deaths of patients with chronic Keshan disease in the selenium supplementation group(101/170,59.4%)and 98 in non-selenium supplementation group(98/132,74.2%).Multivariate analyses suggested that selenium supplementation was associated with a decreased risk of cardiac death(HR 0.39,95%CI 0.28-0.53)after adjustment for baseline age,sex,cigarette smoking,family history of Keshan disease,body mass index(BMI),heart rate,electrocardiogram(ECG)abnonnalities,blood pressure,initial cardiothoracic ratio,left ventricular可ection fractions(LVEF)and whole-blood selenium concentration.Our ten-year follow-up analysis indicated that selenium supplementation,specifically combined with the use of angiotensinconverting cnzyme inhibitor and beta blocker therapy,improved the survival of patients with chronic Keshan disease with congestive heart failure.BMI,selenium deficiency,male,combined ECG abnonnalities,LVEF,and fast heart rate increased the risk of cardiac events. 展开更多
关键词 Keshan DISEASE SELENIUM supplementation FOLLOW-UP
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Identification and functional characterization of ApisOr23 in pea aphid Acyrthosiphon pisum 被引量:1
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作者 HUANG Tian-yu ZHANG Rui-bin +4 位作者 YANG Lu-lu CAO Song Frederic FRANCIS WANG Bing WANG Gui-rong 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2022年第5期1414-1423,共10页
Pea aphid,Acyrthosiphon pisum,is a serious pest of many different leguminous plants,and it mainly relies on its odorant receptors(Ors)to discriminate among host species.However,less is known about the role that Ors pl... Pea aphid,Acyrthosiphon pisum,is a serious pest of many different leguminous plants,and it mainly relies on its odorant receptors(Ors)to discriminate among host species.However,less is known about the role that Ors play in the host plant location.In this study,we identified a novel conserved odorant receptor clade by phylogenetic analysis,and conducted the functional analysis of ApisOr23 in A.pisum.The results showed that the homologous Ors from A.pisum,Aphis glycines and Aphis gossypii share 94.28% identity in amino acid sequences.Moreover,conserved motifs were analyzed using the annotated homologous Or23 from eight aphid species,providing further proof of the high conservation level of the Or23 clade.According to the tissue expression pattern analysis,ApisOr23 was mainly expressed in the antennae.Further functional study using a heterologous Xenopus expression system revealed that ApisOr23 was tuned to five plant volatiles,namely trans-2-hexen-1-al,cis-2-hexen-1-ol,1-heptanol,4’-ethylacetophenone,and hexyl acetate.Among them,trans-2-hexen-1-al,which is one of the main volatile organic compounds released from legume plants,activated the highest response of ApisOr23.Our findings suggest that the conserved Or23 clade in most aphid species might play an important role in host plant detection. 展开更多
关键词 Acyrthosiphon pisum odorant receptor phylogenetic analysis two-electrode voltage clamp trans-2-hexen-1-al
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银叶老鹳草 (Geraniumsylvaticum)种群中诱导保护抗性和病原菌相互作用的研究(英文)
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作者 刘登义 Lars Ericson 《生物多样性》 CAS CSCD 2002年第1期29-37,共9页
本文通过自然植物种群接种实验、人工接种实验和野外调查研究了 (Geraniumsylvaticum)对老鹳草单孢锈菌 (Uromycesgeranii) (长生活史 )的抗病性在受柄锈菌 (Puccinia) (短生活史 )感病前后和受 2种柄锈菌 (P .lev eillei或P .morthieri... 本文通过自然植物种群接种实验、人工接种实验和野外调查研究了 (Geraniumsylvaticum)对老鹳草单孢锈菌 (Uromycesgeranii) (长生活史 )的抗病性在受柄锈菌 (Puccinia) (短生活史 )感病前后和受 2种柄锈菌 (P .lev eillei或P .morthieri)感病后有无区别 ,以及在同一季节里感染同一寄主植物的长生活史单孢锈菌和短生活史柄锈菌间的相互作用。病原菌间的相互作用使寄主植物产生诱导保护抗性。结果表明 ,P .leveillei可诱导寄主植物产生短时间的保护抗性 ,而P .morthieri可能诱导寄主植物产生长时期的保护抗性。诱导保护抗性可能是影响自然植物种群中植病式样的重要因素之一。 展开更多
关键词 病原菌相互作用 诱导保护抗性 银叶老鹳草 柄锈菌
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Rapid increase in numbers and change of land-use in two expanding Columbidae species(Columba palumbus and Streptopelia decaocto)in Algeria 被引量:1
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作者 Djamel Bendjoudi Jean-Francois Voisin +3 位作者 Salaheddine Doumandji Amel Merabet Nassima Benyounes Haroun Chenchouni 《Chinese Birds》 CSCD 2015年第4期246-254,共9页
Background: Investigating population ecology of urban bird species,particularly the invasive and expending spe?cies,is the key for the success of urban management and planning strategies.Methods: Populations of two Co... Background: Investigating population ecology of urban bird species,particularly the invasive and expending spe?cies,is the key for the success of urban management and planning strategies.Methods: Populations of two Columbidae species,the Woodpigeon(Columba palumbus) and the Eurasian Collared Dove(Streptopelia decaocto),were monitored from 1992 to 2010 in the Algiers Sahel,the Mitidja Plain and surround?ing areas(Northern Algeria).Monitoring of species densities was performed by the mapping?plot method.The foraging flight routes of Woodpigeon and the distribution of Eurasian Collared Dove were assessed by systematic observations.Results: The number of counted birds was statistically constant at first years of the survey,and then increased sig?nificantly,beginning from low numbers,their densities accelerated sharply between 2001 and 2006,then reached to an equilibrium state.The significant increase in Woodpigeon's population could be explained by the reduced hunt?ing pressure and by species adaptation to new food resources provided by nearby agriculture.Indeed,monitoring of flight directions of the species revealed the use of agricultural landscapes and habitats,which is a good indicator explaining adaptation and trophic niche of the species.The occurrence of the Eurasian Collared Dove in Algiers began in 2000.Its density experienced a rapid increase with similar trend pattern as that of Woodpigeon.Its distributional range is confined mainly in suburban environments of the Mitidja Plain.Conclusion: The modifications of habitats,urbanization increase and the lessening of hunting in the Mitidja Plain facilitated the rapid expansion of the Eurasian Collared Dove and Woodpigeon as well contributed to the increase in their numbers over time. 展开更多
关键词 Columba palumbus Flight routes Mitidja plain Population dynamics Streptopelia decaocto
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Polymeric Structure and Solid ^(31)P, ^(113)Cd NMR Spectra of Cadmium(II) Dialkyldithiophosphate (Alkyl = n-butyl and i-butyl)
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作者 Ye Gao YIN Willis FORSLING +3 位作者 Dan BOSTROM Oleg ANTZUTKIN Mats LINDBERG Alexander IVANOV 《Chinese Chemical Letters》 SCIE CAS CSCD 2003年第2期188-190,共3页
Two polymeric complexes, [Cd(BTP)2]n 1 and [Cd(i-BTP)2]n 2, were prepared and investigated by solid 31P and 113Cd NMR spectroscopies. The crystal structure of 2 was determined by X-ray diffraction.
关键词 Cadmium(II) complex dialkyldithiophosphate crystal structure solid NMR.
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Analysis of symbiotic microbial status of Atlantic sand dunes forest and its effects on Acacia gummifera and Retama monosperma(Fabaceae)to be used in reforestation
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作者 Abdessamad Fakhech Lahcen Ouahmane Mohamed Hafidi 《Journal of Forestry Research》 SCIE CAS CSCD 2020年第4期1309-1317,共9页
Atlantic forest natural soil flora was tested on two leguminous pioneer species Acacia gummifera and Retama monosperma to be used in rehabilitation programs of the coastal sand dunes forest of the Essaouira region.The... Atlantic forest natural soil flora was tested on two leguminous pioneer species Acacia gummifera and Retama monosperma to be used in rehabilitation programs of the coastal sand dunes forest of the Essaouira region.The rhizospheric soil of two endemic plant species:R.nonosperma and Juniperus phoenicea was sampled and split into two categories,one from native rhizospheric soil,the other of the sterilized rhizospheric soil.Investigation was focused on mycorrhizal formations,but other forms of beneficial symbiosis such as rhizobia and viable soil microflora were also studied.Growth and nutrition variables assessed included lengths of roots and shoots,number of branches,ratio of root to shoot dry mass and water,nitrogen and phosphorus levels.Results showed important mycorrhizal associations in roots of both plants,presence of nodules and abundance of viable soil microflora.J.phoenicea had a 100%frequency of mycorrhizal formation and an intensity of 80%compared to a frequency of 80%and intensity of 54%for R.monosperma.Nodules had the same density of CFU regardless of the origin.Abundance of viable microflora in rhisospheric soil of R.monosperma,J.phoenicea and the control differed significantly.Among the studied variables for A.gummifera and R.monosperma,nitrogen and phosphorus uptakes significantly wit the use of the nonsterilized rhizospheric soil.Both species doubled their phosphorus uptake when colonized by mycorrhizal species,R.monosperma doubled its nitrogen uptake and A.gummifera increased it by seven times compared with the control.No significant difference was noted for the other variables. 展开更多
关键词 Nitrogen Phosphorus Juniperus phoenicea Acacia gummifera Retama monosperma MYCORRHIZAE RHIZOBIA
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Blood meal analysis of tabanid fly after it biting the rare Sumatran rhinoceros
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作者 Jeffrine Japning Rovie-Ryan Zainal Zahari Zainuddin +3 位作者 Wahap Marni Abdul Hamid Ahmad Laurentius N.Ambu Junaidi Payne 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2013年第2期95-99,共5页
Objective:To demonstrate a noninvasive large mammalian genetic sampling method using blood meal obtained from a tabanid fly.Methods:Blood meal was recovered from the abdomen of an engorged tabanid fly(Haematopota sp.)... Objective:To demonstrate a noninvasive large mammalian genetic sampling method using blood meal obtained from a tabanid fly.Methods:Blood meal was recovered from the abdomen of an engorged tabanid fly(Haematopota sp.)which was captured immediately after biting a Sumatran rhino in captivity.The blood was applied on to a Whatman FTAblood card.Subsequent laboratory work was conducted to extract,amplify and sequence the DNA from the sample.Validation was done by sampling the hair follicles and blood samples from the rhinoceros and subjecting it to the same laboratory process.Results:BLAST search and constructed phylogenetic trees confirmed the blood meal samples were indeed from the rhino.Conclusions:This method could be used in the field application to noninvasively collect genetic samples.Collection of tabanids and other haematophagous arthropods(e.g.mosquitoes and ticks)and other blood-sucking parasites(e.g.leeches and worms)could also provide information on vector-borne diseases. 展开更多
关键词 NONINVASIVE DNA sampling Blood MEAL Tabanid FLY Sumatran RHINO
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Synthesis of New 2-Phenylamino-4<i>H</i>-chromene-3-carbonitrile Derivatives and Their Effects on Tumor Cell Lines and against Protein Kinases
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作者 Ali Bouattour Mehdi Fakhfakh +7 位作者 Souhir Abid Ludovic Paquin Rémy Le Guével Thierry Charlier Sandrine Ruchaud Stéphane Bach Jean-Pierre Bazureau Houcine Ammar 《International Journal of Organic Chemistry》 2020年第2期88-103,共16页
The synthesis of 2-phenylimino-4<em>H</em>-chromene-3-carbonitriles <strong>6(a-d)</strong> in good overall yields using an efficient and practical methodology in 3 steps has been implemented i... The synthesis of 2-phenylimino-4<em>H</em>-chromene-3-carbonitriles <strong>6(a-d)</strong> in good overall yields using an efficient and practical methodology in 3 steps has been implemented in this present work. The first step was a heterocyclization between 2-hydroxybenzaldehyde <strong>1</strong> and propanedinitrile <strong>2</strong> which produced 2-iminocoumarin <strong>3</strong> which was submitted to nitrogen/nitrogen displacement in the presence of aromatic primary amine <strong>4</strong>. In the third step, reduction of <strong>5</strong> led to the desired 2-phenylimino-4<em>H</em>-chromene-3-carbonitriles <strong>6</strong>. Compounds <strong>5(a-d)</strong> and <strong>6(a-d)</strong> were evaluated for their potential <em>in vitro</em> cytotoxicity against six selected tumor cell lines (Huh7-D12, Caco2, MDA-MB231, HCT 116, PC3 and NCI-H727) and tested for their protein kinase inhibition on eight selected protein kinases. Among them, compounds <strong>5c</strong> and <strong>6b</strong> exhibited inhibition on HsCK1e (<strong>5c</strong>: 44% and <strong>6b</strong>: 42% at 1 μM) and <strong>5c </strong>for cytotoxicity on PC3 cell lines (63% at 25 μM). 展开更多
关键词 Iminocoumarin benzopyran benzopyran 4H-chromene 2-Amino-4H-chromene Nitrogen/Nitrogen Displacement Protein Kinase Inhibition Cytotoxicity
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Morphological and genetic comparison of two strains of a Prorocentrum species isolated from Zhejiang coastal water of China and Masan Bay of Korea 被引量:3
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作者 陆斗定 王红霞 +4 位作者 黄海燕 夏平 戴鑫烽 GBEL Jeanette JEONG Hae Jin 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2011年第4期832-839,共8页
In this paper, we examined the detailed morphology of two strains of Prorocentrum isolated from the coastal waters of Zhejiang (Wenling area), China, and Masan Bay of Korea. A taxonomic comparison was made among strai... In this paper, we examined the detailed morphology of two strains of Prorocentrum isolated from the coastal waters of Zhejiang (Wenling area), China, and Masan Bay of Korea. A taxonomic comparison was made among strains on the basis of morphological and molecular data. The cellular dimensions of the Chinese Wenling strain (LAMB090508) and Korean strain (PDKS0206) were similar and the cells of both strains were of asymmetric and elongated shape. The posterior end of most cells was rounded. Megacytic zones of aged cells were broader with dense tiny knobs. The roundish nucleus was located in the posterior part of the cell. A few irregular shaped chloroplasts were distributed within the cell. The nucleotide similarity of the two strains, determined from the 5.8S rDNA-ITS sequences, was 99.83%. The comparative results of morphology and molecular analysis suggest that both strains isolated from China and Korea were the identical species, Prorocentrum donghaiense Lu. 展开更多
关键词 东海原甲藻 沿海水域 形态学 分离株 韩国 中国 浙江 遗传
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