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Comparative study of the effects of Tartary buckwheat seed and sprout consumption on the physiological indices and gut microbiota of C57BL/6J mice
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作者 Guohui Nan Haixia Zhao +6 位作者 Qiong Wu Lisong Liu Zichao Guan Chenglei Li Huala Wu Dabing Xiang Qi Wu 《Food Science and Human Wellness》 SCIE CSCD 2024年第2期791-800,共10页
Tartary buckwheat(Fagopyrum tataricum)is a well-known pseudocereal for its health and economic value.However,abundant antinutritional factors(ANFs)reduces its health benefits.As reported,germination can improve the nu... Tartary buckwheat(Fagopyrum tataricum)is a well-known pseudocereal for its health and economic value.However,abundant antinutritional factors(ANFs)reduces its health benefits.As reported,germination can improve the nutritional profile of grains.In this study,we systematically evaluate the safety of Tartary buckwheat seeds(TB)and Tartary buckwheat sprouts(TBS)used as high active ingredients.After evaluating nutrition levels,bioactive compounds and ANFs in TBS during germinating,5^(th)-day TBS were selected as the raw material.C57BL/6J mice were gavaged daily with distilled water,TB,or TBS for 6 weeks.The physiological indices related to ANFs were determined.Results showed that the TB intake tends to generate negative effects on the gut microbiota,and organs.Additionally,upon TB intake,the Fe^(3+)content in serum,trypsin activity in pancreas and jejunum decreased,while the cytokine,IgE,and histamine levels in serum,water content in faeces,cytokine levels in liver and jejunum increased.Conversely,TBS did not induce any obvious negative effects on the above relevant indices and showed better lipid-lowering effect.Altogether,TBS are safer and more effective as a raw material to produce the functional food for long-term consumption with the intention of preventing and treating hyperlipidaemia. 展开更多
关键词 Tartary buckwheat Tartary buckwheat sprouts Antinutritional factors Gut microbiota Health effect
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A Differential Privacy Federated Learning Scheme Based on Adaptive Gaussian Noise
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作者 Sanxiu Jiao Lecai Cai +2 位作者 Xinjie Wang Kui Cheng Xiang Gao 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第2期1679-1694,共16页
As a distributed machine learning method,federated learning(FL)has the advantage of naturally protecting data privacy.It keeps data locally and trains local models through local data to protect the privacy of local da... As a distributed machine learning method,federated learning(FL)has the advantage of naturally protecting data privacy.It keeps data locally and trains local models through local data to protect the privacy of local data.The federated learning method effectively solves the problem of artificial Smart data islands and privacy protection issues.However,existing research shows that attackersmay still steal user information by analyzing the parameters in the federated learning training process and the aggregation parameters on the server side.To solve this problem,differential privacy(DP)techniques are widely used for privacy protection in federated learning.However,adding Gaussian noise perturbations to the data degrades the model learning performance.To address these issues,this paper proposes a differential privacy federated learning scheme based on adaptive Gaussian noise(DPFL-AGN).To protect the data privacy and security of the federated learning training process,adaptive Gaussian noise is specifically added in the training process to hide the real parameters uploaded by the client.In addition,this paper proposes an adaptive noise reduction method.With the convergence of the model,the Gaussian noise in the later stage of the federated learning training process is reduced adaptively.This paper conducts a series of simulation experiments on realMNIST and CIFAR-10 datasets,and the results show that the DPFL-AGN algorithmperforms better compared to the other algorithms. 展开更多
关键词 Differential privacy federated learning deep learning data privacy
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Experimental study on motion and mechanical characteristics of the vertical wheel in the rock-breaking process 被引量:2
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作者 Yan Yang Ying-Xin Yang +3 位作者 Hai-Tao Ren Qing-Liang Qi Ze-Quan Huang Chun-Xiao Zhou 《Petroleum Science》 SCIE EI CAS CSCD 2023年第1期495-506,共12页
Polycrystalline diamond compact(PDC)drill bit often performs with low ROP,short service life and poor stability under complicated and difficult to drill formations.Therefore,a vertical wheel PDC bit is proposed,which ... Polycrystalline diamond compact(PDC)drill bit often performs with low ROP,short service life and poor stability under complicated and difficult to drill formations.Therefore,a vertical wheel PDC bit is proposed,which is a new drill bit technology applying an integrated unit combining the tooth wheel and the rotary shaft thereof.Besides,the experiments on motion and mechanical characteristics of the vertical wheel under the conditions of tooth shape and number of teeth,normal deflection angle of the wheel,and different cutting depth were carried out using variable parameter experimental device,and the movement,force law,and crushing specific work of vertical wheel under different experimental conditions were obtained.The comparative experiments of PDC cutting rock breaking under the conditions of parallel cutting of PDC unit and pre-damage of the wheel were also carried out,and the cutting load of PDC teeth under pre-damage conditions is between 38.72% and 70.95%lower than that of parallel cutting was obtained.Finally,a comparative experiment of indoor drilling between vertical wheel PDC bit and conventional PDC bit was carried out.Results show than when drilling in gravel rock,under the same WOB,the torque response of vertical wheel PDC bit is equivalent to that of the PDC bit,while the ROP of vertical wheel PDC bit is 22.94%-53.33% higher than that of conventional PDC bit,and the threedimensional acceleration of the vertical wheel PDC bit is 19.17%-76.23% of that of the PDC bit.The experimental results contribute to a better understanding of vertical wheels and provide technical support for their use in PDC bits. 展开更多
关键词 Difficult to drill formation Vertical wheel Vertical wheel PDC bit Rock-breaking mechanism Pre-damage
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Response of Distribution Range Against Climate Change and Habitat Preference of Four National Protected Diploderma Species in Tibetan Plateau 被引量:1
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作者 Lin SHI Xiudong SHI +5 位作者 Yuning CAO Yayong WU Haijuan WEI Youhua CHEN Ziyan LIAO Yin QI 《Asian Herpetological Research》 SCIE CSCD 2023年第4期319-330,共12页
Understanding the spatial distribution and habitat preference for rare and endangered species are essential for effective conservation practice.We examined the spatial distribution and habitat preference of four Diplo... Understanding the spatial distribution and habitat preference for rare and endangered species are essential for effective conservation practice.We examined the spatial distribution and habitat preference of four Diploderma species(Diploderma drukdaypo,D.laeviventre,D.batangense,and D.vela),which are endemic to the Qinghai-Tibet Plateau and are currently under state protection.We used the ensembles of small models(ESM)approach and predicted potential distribution ranges of the species in current and two future climate scenarios(SSP126 and SSP585).The degree of overlap between the predicted distribution ranges and existing natural reserves was further analyzed.Habitat preference was examined using a paired quadrat method.Our results predicted that D.drukdaypo has a current distribution range of 600 km^(2),which would decrease to 50 km^(2)and 55 km^(2)under the SSP126 and SSP585 respectively.For D.laeviventre,the current distribution range is 817 km^(2),with minimum changes in the two future climate scenarios(774 km^(2)and 902 km^(2)).For D.batangense,the current distribution range is 875 km^(2),which would expand to 1522 km^(2)and 3340 km^(2)in the two future climate scenarios.Similarly for D.vela,the current distribution range is 1369 km^(2),which would change to 1825 km^(2)and 2043 km^(2)respectively under the two future climate scenarios.The effect of protection of current nature reserves are likely low for those species;we found no overlap(D.drukdaypo,D.laeviventre)or little overlap(D.batangense 2.04%–3.56%,D.vela 15.52%–16.87%)between the currently designated protection area and distribution range under current and future climate scenarios.For habitat preference,stones appear to be the critical habitat element for those species although different species had different stone requirements.Taken together,we provided critical information on potential distribution ranges and habitat preference for four endangered Diploderma species,and confirmed the inadequacy of current nature reserves.The establishment of new or expansion of existing nature reserves is urgent for the conservation of those species. 展开更多
关键词 climate change distribution range habitat preference nature reserve REPTILE
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Bifurcation Analysis and Bounded Optical Soliton Solutions of the Biswas-Arshed Model
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作者 Fahad Sameer Alshammari Md Fazlul Hoque +1 位作者 Harun-Or-Roshid Muhammad Nadeem 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第6期2197-2217,共21页
We investigate the bounded travelling wave solutions of the Biswas-Arshed model(BAM)including the low group velocity dispersion and excluding the self-phase modulation.We integrate the nonlinear structure of the model... We investigate the bounded travelling wave solutions of the Biswas-Arshed model(BAM)including the low group velocity dispersion and excluding the self-phase modulation.We integrate the nonlinear structure of the model to obtain bounded optical solitons which pass through the optical fibers in the non-Kerr media.The bifurcation technique of the dynamical system is used to achieve the parameter bifurcation sets and split the parameter space into various areaswhich correspond to different phase portraits.All bounded optical solitons and bounded periodic wave solutions are identified and derived conforming to each region of these phase portraits.We also apply the extended sinh-Gordon equation expansion and the generalized Kudryashov integral schemes to obtain additional bounded optical soliton solutions of the BAM nonlinearity.We present more bounded optical shock waves,the bright-dark solitary wave,and optical rogue waves for the structure model via these schemes in different aspects. 展开更多
关键词 The Biswas-Arshed model the extended sinh-Gordon equation expansion the generalized Kudryashov approach shock wave double solitons optical singular double solitons chirp-free bright-dark double solitons
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Generalized mixed equilibrium problem in Banach spaces 被引量:7
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作者 张石生 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2009年第9期1105-1112,共8页
This paper uses a hybrid algorithm to find a common element of the set of solutions to a generalized mixed equilibrium problem, the set of solutions to variational inequality problems, and the set of common fixed poin... This paper uses a hybrid algorithm to find a common element of the set of solutions to a generalized mixed equilibrium problem, the set of solutions to variational inequality problems, and the set of common fixed points for a finite family of quasi-C- nonexpansive mappings in a uniformly smooth and strictly convex Banach space. As applications, we utilize our results to study the optimization problem. It shows that our results improve and extend the corresponding results announced by many others recently. 展开更多
关键词 small generalized mixed equilibrium problem variational inequality quasi- Ф-nonexpansive mapping maximal monotone operator monotone mapping
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A NEW ITERATIVE METHOD FOR FINDING COMMON SOLUTIONS OF GENERALIZED EQUILIBRIUM PROBLEM,FIXED POINT PROBLEM OF INFINITE k-STRICT PSEUDO-CONTRACTIVE MAPPINGS,AND QUASI-VARIATIONAL INCLUSION PROBLEM 被引量:5
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作者 刘敏 张石生 《Acta Mathematica Scientia》 SCIE CSCD 2012年第2期499-519,共21页
In this article, we introduce a hybrid iterative scheme for finding a common element of the set of solutions for a generalized equilibrium problems, the set of common fixed point for a family of infinite k-strict pseu... In this article, we introduce a hybrid iterative scheme for finding a common element of the set of solutions for a generalized equilibrium problems, the set of common fixed point for a family of infinite k-strict pseudo-contractive mappings, and the set of solutions of the variational inclusion problem with multi-valued maximal monotone mappings and inverse-strongly monotone mappings in Hilbert space. Under suitable conditions, some strong convergence theorems are proved. Our results extends the recent results in G.L.Acedo and H.K.Xu [2], Zhang, Lee and Chan [8], Wakahashi and Toyoda [9], Takahashi and Takahashi [I0] and S. S. Chang, H. W. Joseph Lee and C. K. Chan [II], S.Takahashi and W.Takahashi [12]. Moreover, the method of proof adopted in this article is different from those of [4] and [12]. 展开更多
关键词 k-strict pseudo-contractive mappings generalized equilibrium problem vis-cosity approximation method variational inclusion problem multi-valuedmaximal monotone mappings s-inverse-strongly monotone mapping
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Ni-Co/Mg-Al catalyst derived from hydrotalcite-like compound prepared by plasma for dry reforming of methane 被引量:9
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作者 Huali Long Yan Xu +4 位作者 Xiaoqing Zhang Shijing Hu Shuyong Shang Yongxiang Yin Xiaoyan Dai 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2013年第5期733-739,共7页
Ni-Co bimetallic catalysts with different Ni/Co content were derived from cold plasma jet decomposition and reduction of hydrotalcite-like compounds containing Ni,Co,Mg and Al,and their catalytic performance was inves... Ni-Co bimetallic catalysts with different Ni/Co content were derived from cold plasma jet decomposition and reduction of hydrotalcite-like compounds containing Ni,Co,Mg and Al,and their catalytic performance was investigated with dry reforming of methane.Experimental results showed that the hydrotalcite-like precursors could be completely decomposed and partly reduced by cold plasma jet,and the Nicontained catalysts exhibited much higher activity than the catalyst without Ni.Especially,the catalyst with Ni/Co ratio of 8/2 achieved not only the highest conversions of 80.3%and 69.3%for CH4 and CO2,respectively,but also the best stability in 100 h testing.The catalysts were characterized by XRD,XPS,TEM and N2 adsorption techniques,and the results showed that the better performance of the 8Ni2Co bimetallic catalyst was attributed to its higher metal dispersion,smaller metal particle size,as well as the interaction effect between Ni and Co,which were brought by the special catalyst preparation method. 展开更多
关键词 dry reforming of methane Ni-Co bimetallic catalyst cold plasma treatment hydrotalcite-like compound
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Thermodynamics and elastic properties of Ta from first-principles calculations 被引量:4
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作者 李强 黄多辉 +4 位作者 曹启龙 王藩侯 蔡灵仓 张修路 经福谦 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第12期412-419,共8页
Within the framework of the quasiharmonic approximation, the thermodynamics and elastic properties of Ta, including phonon density of states (DOS), equation of state, linear thermal expansion coefficient, entropy, e... Within the framework of the quasiharmonic approximation, the thermodynamics and elastic properties of Ta, including phonon density of states (DOS), equation of state, linear thermal expansion coefficient, entropy, enthalpy, heat capacity, elastic constants, bulk modulus, shear modulus, Young's modulus, microhardness, and sound velocity, are studied using the first-principles projector-augmented wave method. The vibrational contribution to Helmholtz free energy is evaluated from the first-principles phonon DOS and the Debye model. The thermal electronic contribution to Helmholtz free energy is estimated from the integration over the electronic DOS. By comparing the experimental results with the calculation results from the first-principles and the Debye model, it is found that the thermodynamic properties of Ta are depicted well by the first-principles. The elastic properties of Ta from the first-principles are consistent with the available experimental data. 展开更多
关键词 FIRST-PRINCIPLES TA THERMODYNAMICS Debye model elastic properties
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Molecular Phylogeny Supports the Validity of Polypedates impresus Yang 2008 被引量:6
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作者 Shulin PAN Ningxin DANG +3 位作者 Jishan WANG Yitao ZHENG Dingqi RAO Jiatang LI 《Asian Herpetological Research》 SCIE 2013年第2期124-133,共10页
The taxonomy of the Asian tree frogs of the Polypedates leucomystax complex, a group of widespread and morphologically similar species, is very controversial. To ascertain the taxonomic status of these species, we inv... The taxonomy of the Asian tree frogs of the Polypedates leucomystax complex, a group of widespread and morphologically similar species, is very controversial. To ascertain the taxonomic status of these species, we investi- gated the historical relationships among representative samples based on - 2 kb of nucleotide sequences from the mito- chondrial 12S rRNA, tRNAvalinc, and 16S rRNA genes. Our phylogeny resolved five well supported lineages (A, B, C, D and E) in the P leucomystax complex. Polypedates impresus from Yunnan, China, Polypedates cf. mutus and Polypedates cf. megacephalus from Guangxi and Yunnan, China, and Laos constructed Clade C, which is monophyletic. In order to recognize the unique position of this clade, we considered P impresus in Clade C as a valid species. Following our phy- logeny, Chinese Polypedates, corresponding to the other four clades, should include four species: P. mutus (Clade A); P. braueri (Clade B); P impresus (Clade C) and P. megacephalus (Clade D). P Ieucomystax (Clade E) is mainly distributed in the Malaysia, Indonesia and Philippines. 展开更多
关键词 Chinese Polypedates nucleotide sequence Polypedates leucomystax complex TAXONOMY
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Structural Characterization of Volatile Components of Rosa Banksiae Ait for Estimation and Prediction of Their Linear Retention Indices and Retention Times 被引量:6
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作者 朱万平 杨善彬 +2 位作者 廖立敏 谭超 舒茂 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2009年第4期391-396,共6页
The molecular electronegativity-distance vector (MEDV) was used to describe the molecular structure of volatile components of Rosa banksiae Ait, and QSRR model was built up by use of multiple linear regression (MLR... The molecular electronegativity-distance vector (MEDV) was used to describe the molecular structure of volatile components of Rosa banksiae Ait, and QSRR model was built up by use of multiple linear regression (MLR). Furthermore, in virtue of variable screening by the stepwise multiple regression technique, the QSRR models of 10 and 6 variables and linear retention index (LRI) 10, 7 and 6 varieables were built up by combinating MEDV with the Ultra2 column GC retention time (tR) of 53 volatile components of Rosa Banksiae Air. The multiple correlation coefficients (R) of modeling calculation values of QSRR model were 0.906, 0.906, 0.949, 0.943 and 0.949, respectively. The cross-verification multiple correlation coefficients (RCV) were 0.903, 0.904, 0.867, 0.901 and 0.904, respectively. The results show that the models constructed could provide estimation stability and favorable predictive ability. 展开更多
关键词 molecular electronegativity-distance vector (MEDV) DESCRIPTOR quantitative structure-retention relationship (QSRR) linear retention indices (LRI)
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Cloning and characterization of a stearoyl-ACP desaturase gene from Jatropha curcas 被引量:4
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作者 罗通 马丹炜 +4 位作者 徐莺 邓骛远 肖猛 卿人韦 陈放 《Journal of Shanghai University(English Edition)》 CAS 2007年第2期182-188,共7页
Using degenerate primers and RT-PCR, RACE techniques, a 1491 bp cDNA segment of stearoyl-acyl carrier protein desaturase (SAD) is cloned from developing seeds of Jatropha curcas L. The segment contains a 1191 bp of ... Using degenerate primers and RT-PCR, RACE techniques, a 1491 bp cDNA segment of stearoyl-acyl carrier protein desaturase (SAD) is cloned from developing seeds of Jatropha curcas L. The segment contains a 1191 bp of complete open reading frame (ORF). Analysis in the BLAST on NCBI shows that Jatropha curcas SAD (JSAD) gene encodes a protein precursor composed of a signal peptide of 33 amino acids and a mature peptide of 363 amino acids. The homological analysis shows that JSAD has high level of homology both in nucleotide sequence and in amino acid sequence to other plants SADs. The nucleotide and peptide identity of JSAD to Ricinus communis SAD (RSAD) is up to 89% and 96.2% respectively. Molecular modeling of JSAD indicates that its three-dimensional structure strongly resembled the crystal structure of RSAD. 展开更多
关键词 Jatropha curcas stearoyl-acyl carrier protein desaturase fatty acid gene cloning bioinformatics analysis
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Ni/MgO catalyst prepared using atmospheric high-frequency discharge plasma for CO_2 reforming of methane 被引量:3
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作者 Pan Qin Huiyuan Xu +4 位作者 Huali Long Yi Ran Shuyong Shang Yongxiang Yin Xiaoyan Dai 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2011年第5期487-492,共6页
A new type of Ni/MgO catalyst was prepared using atmospheric high-frequency discharge cold plasma. The influences of conventional method, plasma method, and plasma plus calcination method on the catalytic activity wer... A new type of Ni/MgO catalyst was prepared using atmospheric high-frequency discharge cold plasma. The influences of conventional method, plasma method, and plasma plus calcination method on the catalytic activity were studied and the CO2 reforming of methane was chosen as the probe reaction. The catalysts were characterized by X-ray diffraction (XRD), transmission electron microscope (TEM), X-ray photoelectron spectroscopy, and CO2 temperature-programmed surface reaction techniques. The results suggested that the nickel-based catalyst prepared by plasma plus calcination method possessed a smaller particle size and a higher dispersion of active component, better low-temperature activity and enhanced anti-coking ability. The conversion of CO2 and CH4 was 90.70% and 89.37%, respectively, and the reaction lasted for 36 h without obvious deactivation under 101.325 kPa and 750°C with CO2/CH4 = 1/1. 展开更多
关键词 Ni/MgO catalyst carbon dioxide METHANE REFORMING atmospheric high-frequency discharge cold plasma
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Algorithms of common solutions to quasi variational inclusion and fixed point problems 被引量:2
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作者 张石生 李向荣 陈志坚 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2008年第5期571-581,共11页
The purpose of this paper is to present an iterative scheme for finding a common element of the set of solutions to the variational inclusion problem with multivalued maximal monotone mapping and inverse-strongly mono... The purpose of this paper is to present an iterative scheme for finding a common element of the set of solutions to the variational inclusion problem with multivalued maximal monotone mapping and inverse-strongly monotone mappings and the set of fixed points of nonexpansive mappings in Hilbert space.Under suitable conditions, some strong convergence theorems for approximating this common elements are proved. The results presented in the paper not only improve and extend the main results in Korpelevich(Ekonomika i Matematicheskie Metody,1976,12(4):747-756),but also extend and replenish the corresponding results obtained by Iiduka and Takahashi(Nonlinear Anal TMA,2005,61(3):341-350),Takahashi and Toyoda(J Optim Theory Appl,2003, 118(2):417-428),Nadezhkina and Takahashi(J Optim Theory Appl,2006,128(1):191- 201),and Zeng and Yao(Taiwan Residents Journal of Mathematics,2006,10(5):1293-1303). 展开更多
关键词 variational inclusion multi-valued maximal monotone mapping inversestrongly monotone mapping metric projection fixed point nonexpansive mapping
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A New Species of the Genus Thermophis(Serpentes: Colubridae) from Shangri-La, Northern Yunnan, China, with a Proposal for an Eclectic Rule for Species Delimitation 被引量:5
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作者 Lifang PENG Changhu LU +2 位作者 Song HUANG Peng GUO Yaping ZHANG 《Asian Herpetological Research》 SCIE 2014年第4期228-239,共12页
The hot-spring snakes,Thermophis, were previously known only from the Tibet Autonomous Region and Western Sichuan, China. During the past two years, three adult hot-spring snakes (2 females, 1 male) were sampled in ... The hot-spring snakes,Thermophis, were previously known only from the Tibet Autonomous Region and Western Sichuan, China. During the past two years, three adult hot-spring snakes (2 females, 1 male) were sampled in Shangri-La, northern Yunnan, China, thus expanding their known distribution region towards the southeast. This site is the southeastern-most corner of the Tibetan Plateau and the southernmost tip of the Hengduan Mountains (Mts.). Phylogenetic analysis of mitochondrial (mt) and nuclear (n) DNA segments suggested that the three specimens belong to the genus ofThermophis. Morphologically, the new species is more similar toT. zhaoermii. However, it is distinguished fromT.zhaoermiiin the number of maxillary teeth (15), distance between the two eyes/head width, rostral width/height, mental width/height, in one character limited to female: head width/length, and in four characters restricted to male: occurrence of the reduction from 10 to 8 (8 to 6, 6 to 4) scales in each dorsal row on the tail. There are differences in morphology, genetics (mtDNA, nDNA), and geography between the putative new species andT.zhaoermii,the new species meets our proposed eclectic and feasible "four-differences" rule. 展开更多
关键词 morphology PHYLOGENETICS "four-differences" rule Thermophis Shangrila sp. nov.
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Phylogenetic Analyses Reveal a Unique Species of Elaphe(Serpentes,Colubridae)New to Science 被引量:4
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作者 LING Chen LIU Shaoying +4 位作者 HUANG Song Frank T.Burbrink GUO Peng SUN Zhiyu ZHAO Jie 《Asian Herpetological Research》 SCIE 2010年第2期90-96,共7页
The snakes comprising the monophyletic group referred to as ratsnakes are found throughout Asia,Europe and the New World.Recently,three snake samples likely belonging to the ratsnakes were collected in Zoige County,Si... The snakes comprising the monophyletic group referred to as ratsnakes are found throughout Asia,Europe and the New World.Recently,three snake samples likely belonging to the ratsnakes were collected in Zoige County,Sichuan Province,China.Species identity was difficult to delimit morphologically because the specimens were juveniles and partially damaged.Subsequently,a molecular phylogenetic approach was used.Portions of three mitochondrial genes(cyt b,ND4 and 12S rRNA) were sequenced and analyzed.The results showed that they were sister to the genus Elaphe.Very little genetic variation was found among the three samples.The minimum genetic distances between these samples and those within Elaphe were greater than any currently recognized species within the genus.We conclude that this likely represents a new species within the genus Elaphe.Adult specimens and a morphologic description are needed for further study. 展开更多
关键词 Elaphe ratsnake phylogenetic analysis mitochondrial gene genetic distance
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Disordered Translocation is Hastening Local Extinction of the Chinese Giant Salamander 被引量:7
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作者 Guocheng SHU Ping LIU +8 位作者 Tian ZHAO Cheng LI Yinmeng HOU Chunlin ZHAO Jie WANG Xiaoxiao SHU Jiang CHANG Jianping JIANG Feng XIE 《Asian Herpetological Research》 SCIE CSCD 2021年第3期271-279,共9页
Biodiversity is declining globally by an unprecedented extinction rate.This is especially true for amphibians,accounting for 24.3%of all threatened vertebrates.As the largest extant amphibian species in the world,wild... Biodiversity is declining globally by an unprecedented extinction rate.This is especially true for amphibians,accounting for 24.3%of all threatened vertebrates.As the largest extant amphibian species in the world,wild populations of the Chinese giant salamander(Genus Andrias)(CGS)have decreased dramatically because of overexploitation and habitat degradation.Translocation has become an important strategy for restoring threatened wild populations worldwide.However,disordered tra nsloca tion usually has negative effects on the native populations.We provide an overview of CGS translocation and show that disordered translocation can increase local population extinction.Nearly four times the estimated number of wild individuals have been released across China.There a re three types of translocation used for CGS,namely,reinforcement,reintroduction and ecological replacement,the last of which accounts for over one-third of translocations.Our genetic screening revealed that most released individuals were not from local populations,with one to four lineages detected in every release site(n=6).This disordered translocation can potentially reduce the genetic integrity of original populations.Hence,we suggest suspending current CGS translocation activities immediately,until more robust measures can be developed and implemented to improve the current translocation program,especially with respect to lineage identifica tion a nd the identifica tion of appropriate release sites. 展开更多
关键词 Chinese giant salamander genetic test TRANSLOCATION CONSERVATION wild population
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Influence of MgO contents on silica supported nano-size gold catalyst for carbon monoxide total oxidation 被引量:2
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作者 Huiyuan Xu Weiyi Li +1 位作者 Shuyong Shang Chunrong Yan 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2011年第5期498-502,共5页
A series of nano-size gold catalysts were prepared by deposition-precipitation method using silica material promoted with different amounts of MgO as the carrier. The influences of MgO addition on the structure and pr... A series of nano-size gold catalysts were prepared by deposition-precipitation method using silica material promoted with different amounts of MgO as the carrier. The influences of MgO addition on the structure and property of the nano-size gold catalysts were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), O2 temperature-programmed desorption (O2-TPD), and inductively coupled with plasma atomic emission spectroscopy (ICP-AES) techniques. The total oxidation of CO was chosen as the probe reaction. The results suggest that for the gold catalysts supported on the silica material after MgO modification, the size of the gold particles is pronouncedly reduced, the oxygen mobility is enhanced, and the catalytic activity for low-temperature CO oxidation is greatly improved. The gold catalyst modified by 6 wt% MgO (Mg/SiO2 weight ratio) shows higher CO oxidation activity, over which the temperature of CO total oxidation is lower about 150 K than that over the silica directly supported gold catalyst. 展开更多
关键词 new nano-size gold catalyst CO oxidation MGO SIO2 structure activity relationship
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Promoter effect of La2O3 on gold catalyst with different textural structures 被引量:2
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作者 Huiyuan Xu Jingjie Luo +2 位作者 Shenying Xu Denglei Zhu Wei Chu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2016年第5期854-860,共7页
Silica supported gold nanoparticles were synthesized and promoted by lanthanum oxide as dopant. The influences of LaOand silica textural structure on the gold dispersion, formation of active species, crystalline compo... Silica supported gold nanoparticles were synthesized and promoted by lanthanum oxide as dopant. The influences of LaOand silica textural structure on the gold dispersion, formation of active species, crystalline composition and the reacting role of dopants were studied in detail. The characterization results suggested that the dispersion of gold nanoparticles depended on the textural structure of silica without lanthanum oxide doping where small mesopores are more preferable to disperse gold nanoparticles. The addition of lanthanum oxide largely increased the dispersion of gold nanoparticles and oxygen active sites independent of the textural structure of silica support. The interaction between lanthanum oxide and silica enhanced by the synergy facilitated the release of oxygen vacancies and transition of active oxygen species. In addition, the chemical properties were greatly changed after lanthanum oxide addition which was only inconspicuously impacted by the initial textural structure of silica supports, shedding light on the further design of economic gold catalyst based on simple synthesis method. 展开更多
关键词 Gold catalysis Catalyst design Au-metal synergy CO oxidation
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Interaction of two edge dislocations in free-space propagation 被引量:2
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作者 何德 高曾辉 +1 位作者 闫红卫 吕百达 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第1期352-357,共6页
This paper studies in detail the interaction of two edge dislocations nested in a Gaussian beam propagating in free space. It shows that in free-space propagation the edge dislocations are unstable and vanish, and two... This paper studies in detail the interaction of two edge dislocations nested in a Gaussian beam propagating in free space. It shows that in free-space propagation the edge dislocations are unstable and vanish, and two noncanonical vortices with opposite topological charge take place when off-axis distances cl and c2 of two edge dislocations are nonzero, and the condition k2w08+ 32c1c2(w02- 2C1C2)Z2 〉 0 is fulfilled (k-wave number, w0-waist width). A noncanonical vortex appears when one off-axis distance is zero. However, one edge dislocation is stable when two edge dislocations are perpendicular and one off-axis distance is zero. Two perpendicular edge dislocations both with zero off-axis distance are also stable. The analytical results are illustrated by numerical examples. 展开更多
关键词 edge dislocation interaction optical vortex free-space propagation
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