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A Review of the Tetrapod Track Record in China,with Special Reference to Type Ichnospecies:Implications for Ichnotaxonomy and Paleobiology

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Acta Geologica Sinica(English Edition) 2013年第1期87卷 1-20页

作者： Martin G.LOCKLEY LI Jianjun LI Rihui Masaki MATSUKAWA Jerald d.harris XING Lida University of Colorado denver Dinosaur Tracks Research Group Beijing Museum of Natural History Museum Qingdao Institute of Marine Geology China Geological Survey department of Environmental Sciences Tokyo Gakugei University department of Physical Sciences Dixie State College department of Biological Sciences University of Alberta11455 Saskatchewan Drive

＂Splitting＂ and ＂lumping＂ are perpetual problems in vertebrate, especially dinosaur, ichnotaxonomy. Chinese dinosaur ichnotaxonomy, which began in 1940, provides a series of interesting case studies, highlighting the dual problems of historical and dubious ichnotaxonomy. Chinese Mesozoic tetrapod track types have been placed into 63 ichnospecies （one Triassic, 28 Jurassic, and 34 Cretaceous）, exclusive of other, non-type ichnospecies or ichnotaxa identified from China. Fifty-two （~83%） of these 63 tetrapod ichnospecies were placed in monospecific ichnogenera. At the ichnogenus level, we prune---either by recognizing nomina dubia or by synonymy--17 from the list of 53 dinosaurian ichnogenera （a 32% reduction）, leaving 36 ichnotaxa that we consider valid. Most of the cuts affect Jurassic theropod ichnotaxa, which are reduced from 23 to only nine because most ichnogenera are subjective junior synonyms of Grallator and Eubrontes. Fewer Chinese Cretaceous ichnotaxa （only six of 21 ichnogenera） are obvious nomina dubia or subjective synonyms, suggesting greater east Asian endemism during this time. Because ichnospecies differences are subtle, we provisionally retain ichnospecies as valid pending detailed comparative analyses of congeneric ichnospecies. This synthesis is long overdue and is necessary to address problems of historical and provincial ichnotaxonomy, which severely hamper comparisons of tetrapod ichnofaunas in space and time.

关键词： dinosaurs birds theropods ichnotaxonomy Mesozoic China

记河北赤城上侏罗统-下白垩统土城子组窄足龙-巨齿龙(兽脚类恐龙)足迹组合及其古生态学意义(英文)

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古脊椎动物学报 2011年第4期49卷 423-434页

作者：邢立达 Jerald d.harris Gerard d.GIERLINSKI 加拿大阿尔伯塔大学生物科学系埃德蒙顿T6G2E9 中国科学院脊椎动物进化系统学重点实验室北京100044 美国迪克西州立学院自然科学系犹他州圣乔治84770 侏罗纪公园波兰奥斯特罗维茨427-400 波兰地质研究所华沙400-975

记述了河北省赤城县落凤沟化石点163个窄足龙足迹(Therangospodus isp.)。当该地区洪水泛滥时,同样的造迹者留下了5个游泳迹。一个异常大的足迹和一道疑似尾迹被归入巨齿龙足迹(Megalosauripus isp.)。土城子组7个主要足迹化石点表明,... 详细信息

记述了河北省赤城县落凤沟化石点163个窄足龙足迹(Therangospodus isp.)。当该地区洪水泛滥时,同样的造迹者留下了5个游泳迹。一个异常大的足迹和一道疑似尾迹被归入巨齿龙足迹(Megalosauripus isp.)。土城子组7个主要足迹化石点表明,兽脚类的似鹬龙足迹型(Grallator morphotype)占据主导地位,这些足迹型的大小在各个足迹化石点都有着特定的范围。如果这些大小不同的足迹属于同一种造迹者,则暗示着同年龄的成员在特定年龄时会共同栖息在一起,在动物行为学上类似现生的一些蜥蜴和短吻鳄;如果这些足迹由不同的造迹者组成,则暗示着不同大小的种(主要表现在小型动物)可能拥有自己的领地,并特意避免与其他动物(特别是大型动物)相接触,在动物行为学上类似现生的肉食性哺乳动物。

关键词：河北赤城侏罗-白垩纪界线土城子组窄足龙足迹巨齿龙足迹兽脚类游泳迹

温室内CO_2浓度的计算机控制及其在估算作物光合作用中的应用

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气象科技 1990年第3期18卷 61-67页

作者： R.B.Matthews B.Marshall R.A.Saffell d.harris 马树庆

本文介绍一个监测并控制五个玻璃试验温室内CO_2浓度的计算机自动控制系统。在计算机控制下,通过一个CO_2测定系统向每个温室输入纯CO_2气体,使其内部CO_2浓度与室外保持相等(CO_2浓度由红外气体分析仪测定)。在CO_2浓度测定的间隔期间... 详细信息

本文介绍一个监测并控制五个玻璃试验温室内CO_2浓度的计算机自动控制系统。在计算机控制下,通过一个CO_2测定系统向每个温室输入纯CO_2气体,使其内部CO_2浓度与室外保持相等(CO_2浓度由红外气体分析仪测定)。在CO_2浓度测定的间隔期间,温室所需要的CO_2输入速率根据通风速率、未来的和现时的CO_2浓度计算确定。通过预先用N_2O气体跟踪确定的风机定位状态和风速的关系计算通风率。通过放在地面上的容器内获得的碳酸盐的重量观测土壤呼吸。在其它CO_2通量已确定后,用其剩余额估算作物净光合作用。该系统很可靠,且已在许多热带作物净光合作用的光响应特征曲线研究中得到应用。

关键词：计算机控制 CO2浓度计算机自动控制气体分析仪浓度差净光合作用作物光合作用气流计通风率土壤呼吸

Engineering and characterization of dehalogenase enzymes from delftia acidovorans in bioremediation of perfluorinated compounds

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Synthetic and Systems Biotechnology 2022年第2期7卷 683-688页

作者： Jackson d.harris Collin M.Coon Megan E.doherty Eamon A.McHugh Margaret C.Warner Conley L.Walters Olivia M.Orahood Abigail E.Loesch david C.Hatfield John C.Sitko Erin A.Almand J.Jordan Steel department of Biology United Stated Air Force AcademyColorado SpringsCO80840USA department of Biochemistry United States Air Force AcademyColorado SpringsCO80840USA department of Civil Engineering United States Air Force AcademyColorado SpringsCO80840USA

Per-and Polyfluorinated alkyl substances(PFAS)are a broad class of synthetic compounds that have fluorine substituted for hydrogen in several or all locations and are globally categorized as PFCs(perfluorochemicals;commonly called fluorinated chemicals).These compounds have unique chemical and physical properties that enable their use in non-stick surfaces,fire-fighting efforts,and as slick ***,recent concerns over the health effects of such compounds,specifically perfluorooctanoic acid and perfluorooctane sulfonic acid(PFOA,PFOS;PFOA/S),have led to increased attention and research by the global community into degradation *** this study,soil samples from PFAS-contamination sites were cultured and screened for microbes with PFOA/S degradation potential,which led to the identification of delftia *** was found that *** isolated from PFAS-contaminated soils was capable of growth in minimal media with PFOA as a sole carbon resource,and an observable fluoride concentration increase was observed when cells were exposed to *** suggests potential activity of a dehalogenase enzyme that may be of use in PFOA or PFAS microbial remediation *** associated haloacid dehalogenases have been identified in the *** genome and have been engineered for expression in Escherichia coli for rapid production and *** enzymes have shown potential for enzymatic defluorination,a significant step in biological degradation and removal of PFOA/S from the *** hypothesize that bioremediation of PFAS using naturally occurring microbial degradation pathways may represent a novel approach to remove PFAS contamination.

关键词： iGEM PFAS Bioremediation Bioengineering delftia acidovorans

构巢曲霉pyrG在维持胞内尿嘧啶稳态中起关键作用

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构巢曲霉pyrG在维持胞内尿嘧啶稳态中起关键作用

TRANSIMIdIZATION IN THERMOPLASTIC POLYIMIdES

2012年中国菌物学会学术年会

作者： Steven d.harris department of Plant Pathology University of Nebraska-LincolnLincolnNebraska 68588-0660United States of America

＜正＞Tight control of intracellular uracil level is believed to be important for reducing the occurrence of uracil incorporation into *** this study,we found that orotidine 5’-phosphate decarboxylase,which catalyzes the conversion of orotidine monophosphate（OMP） to uridine monophosphate（UMP）,is critical for maintaining uracil at a low concentration in cells in the presence of exogenous uracil in Aspergillus *** exogenous uracil and its derivatives had more inhibitory effects on the growth of OMP decarboxylase mutants than the wild type,and induced sexual development in the OMP decarboxylase mutants but not the wild *** of transcriptomic responses to excessive exogenous uracil by digital gene expression profiling（dGE） revealed that genes related to sexual development were transcriptionally activated in the OMP decarboxylase mutants but not in the wild type. Quantitative analysis by HPLC showed that the cellular uracil level is 6.5 times higher than that of the wild type in the presence of exogenous *** addition,we found that sorbitol,sucrose and glucose at high concentrations have an OMP decarboxylase-dependent inhibitory effect on A. nidulans ***,this study not only provides new information on uracil recycling and the adaptation to excessive uracil but also reveals the potential effects of OMP decarboxylase on fungal growth and development.

关键词： Aspergillus nidualans orotidine 5’-phosphate decarboxylase pyrG uracil sexual development

来源： cnki会议评论

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Chinese Journal of Polymer Science 1999年第2期17卷 171-184页

作者： Yoan Kim doyun Kim Frank W.harris Stephen Z.d.Cheng Maurice Morton Institute and department of Polymer Science The University of Akron Akron Ohio 44325-3909 USAMaurice Morton Institute and Department of Polymer Science The University of Akron Akron Ohio 44325-3909 USAMaurice Morton Institute and Department of Polymer Science The University of Akron Akron Ohio 44325-3909 USAMaurice Morton Institute and Department of Polymer Science The University of Akron Akron Ohio 44325-3909 USA

In order to improve the processibility in thermoplastic polyimides, a new method, termed the'reactive plasticizer' approach, has been proposed. This method uses a small amount (5～15 mol%) of a lessactivated, weak nucleophilic diamine co-monomer as a 'reactive plasticizer' to obtain copolyimide resinswhich possess relatively low viscosity at low temperatures and can be readily processed through the autoclavecycle at low pressures. during a high temperature treatment, the reactive plasticizers join the reaction to formhigh molecular weight copolyimides, and the preferred material properties are thus achieved. The mosteffective reactive plasticizer is aromatic heterocyclic diamines, such as 2, 6-diaminopyridine diamine (dAP),and the transimidization involved with a reactive plasticizer has been proposed to play a major role for thesuccess of this approach. In order to understand the transimidization mechanism, three steps have been takenin this research: first, a copolyimide system of 50% of dAP and 50% 1, 4 -bis [4-aminophenoxy] benzenediamine (dOdA) with 100% of 2, 2'-bis[4-(3, 4-dicarboxyphenoxy)phenyl] propane dianhydride (Ultem^(R)dA) is prepared. Second, several specifically designed polyimide mixture systems were used, and they consistof two homopolyimides: one is Ultem^(R) dA-dOdA, and the other is Ultem^(R) dA-dAP. The third step is toinvestigate two mixture systems in which Ultem^(R) dA-dOdA is mixed with dAP monomer solution andUltem^(R) dA-dAP is mixed with dOdA monomer solution. For all systems, with increasing degree oftransimidization upon heat-treatment, the chain structures of the mixtures and their thermal and dynamicmechanical transition behaviors are investigated via one-dimensional and two-dimensional nuclear magneticresonance, differential scanning calorimetry, and dynamic mechanical analysis experiments. Experimentalresults indicate that in the mixture of two homopolyimides, transimidization takes place much moreefficiently in solution than in th

关键词： Transmidization Thermoplastic polyimides

In vitro and in vivo application of RNA interference for targeting genes involved in peritrophic matrix synthesis in a lepidopteran system

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Insect Science 2013年第1期20卷 92-100页

作者： Umut Toprak doug Baldwin Martin Erlandson Cedric Gillott Stephanie harris dwayne d. Hegedus Agriculture and Agri-Food Canada Ottawa Ontario Canada department of Biology University of Saskatchewan Canada department of Plant Protection Faculty of Agriculture University of Ankara Turkey department of Food and Bioproduct Sciences University of Saskatchewan Saskatoon SK Canada

The midgut of most insects is lined with a semipermeable acellular tube, the peritrophic matrix （PM）, composed of chitin and proteins. Although various genes encoding PM proteins have been characterized, our understanding of their roles in PM structure and function is very limited. One promising approach for obtaining functional information is RNA interference, which has been used to reduce the levels of specific mRNAs using double-stranded RNAs administered to larvae by either injection or feeding. Although this method is well documented in dipterans and coleopterans, reports of its success in lepidopterans are varied. In the current study, the silencing midgut genes encoding PM proteins （insect intestinal mucin 1, insect intestinal mucin 4, PM protein 1） and the chitin biosynthetic or modifying enzymes （chitin synthase-B and chitin deacetylase 1） in a noctuid lepidopteran, Mamestra configurata, was examined in vitro and in vivo. In vitro studies in primary midgut epithelial cell preparations revealed an acute and rapid silencing （by 24 h） for the gene encoding chitin deacetylase 1 and a slower rate of silencing （by 72 h） for the gene encoding PM protein 1. Genes encoding insect intestinal mucins were slightly silenced by 72 h, whereas no silencing was detected for the gene encoding chitin synthase-B. In vivo experiments focused on chitin deacetylase 1, as the gene was silenced to the greatest extent in vitro. Continuous feeding of neonates and fourth instar larvae with double-stranded RNA resulted in silencing of chitin deacetylase 1 by 24 and 36 h, respectively. Feeding a single dose to neonates also resulted in silencing by 24 h. The current study demonstrates that genes encoding PM proteins can be silenced and outlines conditions for RNA interference by per os feeding in lepidopterans.

关键词： chitin deacetylase chitin synthase-B lepidoptera peritrophic matrix,peritrophin RNA interference

Bayesian Classifier Based on Robust Kernel density Estimation and.harris Hawks Optimisation

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International Journal of Internet and distributed Systems 2024年第1期6卷 1-23页

作者： Bi Iritie A-d Boli Chenghao Wei School of Computer Science Hubei University of Technology Wuhan China

In real-world applications, datasets frequently contain outliers, which can hinder the generalization ability of machine learning models. Bayesian classifiers, a popular supervised learning method, rely on accurate probability density estimation for classifying continuous datasets. However, achieving precise density estimation with datasets containing outliers poses a significant challenge. This paper introduces a Bayesian classifier that utilizes optimized robust kernel density estimation to address this issue. Our proposed method enhances the accuracy of probability density distribution estimation by mitigating the impact of outliers on the training sample’s estimated distribution. Unlike the conventional kernel density estimator, our robust estimator can be seen as a weighted kernel mapping summary for each sample. This kernel mapping performs the inner product in the Hilbert space, allowing the kernel density estimation to be considered the average of the samples’ mapping in the Hilbert space using a reproducing kernel. M-estimation techniques are used to obtain accurate mean values and solve the weights. Meanwhile, complete cross-validation is used as the objective function to search for the optimal bandwidth, which impacts the estimator. The harris Hawks Optimisation optimizes the objective function to improve the estimation accuracy. The experimental results show that it outperforms other optimization algorithms regarding convergence speed and objective function value during the bandwidth search. The optimal robust kernel density estimator achieves better fitness performance than the traditional kernel density estimator when the training data contains outliers. The Naïve Bayesian with optimal robust kernel density estimation improves the generalization in the classification with outliers.

关键词： Classification Robust Kernel density Estimation M-Estimation harris Hawks Optimisation Algorithm Complete Cross-Validation

NOVEL POLYMER WIdE VIEWING ANGLE COMPENSATION FILMS FOR LIQUId CRYSTAL dISPLAYS(LCdS)

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Chinese Journal of Polymer Science 2003年第2期21卷 223-230页

作者： JasonJ.Ge BruceF.Li FrankW.harris StephenZ.d.Cheng StephenZ.d.Cheng TheMauriceMortonInstituteanddepartmentofPolymerScience TheUniversityofAkronAkronOhio44325-3909USA InvitedlecturepresentedattheInternationalSymposiumonPolymerPhysics 2002QingdaoChinaReceivedAugust312002

We report on generating uniaxial negative birefringent compensation films, made of specifically designedpolyimides. These polymers were synthesized via a polycondensation of dianhydride [such as 2, 2' -bis(3, 4-dicarboxyphenyl)hexafluoropropane dianhydride] and 2, 2'-bis(trifluoromethyl)-4,4'-diaminobiphenyl. The uniaxial negative birefringent (n_x =n_y > n_z) polyimide substrates are achieved using a solution-casting method in conventional solvents, which exhibit thedesirable optical phase retardation [(n_x - n_z)×d] values from 50 to 400 nm varying with the film thickness. In thesepolyimide films, the long chain rigid molecules adopt intrinsic planar orientaion. In detail, the majority of phenylene-imiderings and phenylenes preferentially adopt nearly planar conformations parallel to the film substrae. In addition, these filmsalso possess high transparency (or transmittance) and little color shift. The unique color dispersion curve indicates that thistype of materials is very suitable for the applications in LCds due to an excellent mimic for the retardation color dispersioncurve with respect to LC molecules. Significantly low in-plane retardation (d film toachieve sufficiently high contrast ratio while highly negative retardation dramatically suppresses the gray scale inversion toimprove the viewing angle performance in a variety of new mode LCds.

关键词： Compensation films Liquid crystal displays Polyimides