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植物组织培养(一)

辽宁农业科学 1979年第5期 49-55页

作者： dennis n.butcher David S.Ingram 范胜兰

植物组织培养是研究植物发生、发育、生理、遗传及育种的主要手段之一,近年来国内外发展很快,应用范围越来越广。国内在花粉培养方面进展比较迅速,体细胞杂交工作已开始进行,许多有关的农业科研人员迫切需要一本入门指南,而一般这方面... 详细信息

植物组织培养是研究植物发生、发育、生理、遗传及育种的主要手段之一,近年来国内外发展很快,应用范围越来越广。国内在花粉培养方面进展比较迅速,体细胞杂交工作已开始进行,许多有关的农业科研人员迫切需要一本入门指南,而一般这方面的著作或为巨著或为专论,很少有深入浅出,通俗易懂,有理论,有方法的小书。

关键词：愈伤组织生长素细胞分裂素创伤组织植物组织培养植物组培被子植物花药发育

A Practical Approach of Developing Mathematical Model for All Speed Governors

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Journal of Shanghai Jiaotong university(Science) 2005年第2期10卷 175-181页

作者：王永生 dennis n.Assanis 张煜盛 Inst. of Energy & Power Huazhong Univ. of Science and Technology Wuhan 430074 China 201 Mail-Box Naval Univ. of Eng. Wuhan 430033 Dept. of Mechanical Eng. & Applied Mechanics Univ. of Michigan 48109-2125 USA

The paper introduced a special approach for diesel’s all-speed-governor modeling, which, in some cases, could solve the knotty problem frequently met in computer simulation of diesel propulsion system or diesel generating set. Suppose that it is hard to get a control-oriented governor mathematical model when the general approaches, the analytical approach or the experimental approach, are applied, and that an open-loop step response of the diesel engine and its system is available by means of computer simulation, the critical three parameters of a governor mathematical model, the proportional gain K_p, integral time constant K_i, and derivative time constant K_d, can be determined by use of PID tuning method which are widely applied in industrial process control. This paper discussed the train of thought of the approach, precondition, procedure, several modifications of the classical PID model, and some points for attention. A couple of case studies were given to demonstrate the effectiveness of this approach.

关键词： computer simulation mathematical model diesel engine speed governor PID controller

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Spatially-graded 3D-printed viscoelastic truss metamaterials for impact trajectory control and energy absorption

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Theoretical & Applied Mechanics Letters 2024年第5期14卷 378-385页

作者： Kaoutar Radi Raphaël n.Glaesener Siddhant Kumar dennis M.Kochmann Mechanics&Materials Lab Department of Mechanical and Process EngineeringETH Zürich 8092Switzerland Mechanics&Materials Computing Lab Department of Materials Science&EngineeringTU Delft 2628 CNNetherlands

This study demonstrates that two-and three-dimensional spatially graded,truss-based polymeric-material metamaterials can be designed for beneficial impact mitigation and energy absorption *** a combination of numerical and experimental techniques,we highlight the broad property space of periodic viscoelastic trusses,realized using 3D printing via selective laser *** beyond periodic designs,we investigate the impact response of spatially variant viscoelastic lattices in both two and three *** result reveal that introducing spatial variations in lattice topology allows for redirecting of the impact trajectory,opening new opportunities for engineering and tailoring lightweight materials with target impact *** is achieved through the combined selection of base material and metamaterial design.

关键词： Metamaterial 3D Printing Viscoelasticity Impact Truss Finite element method

Pancreatic insulinoma:current issues and trends

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Hepatobiliary & Pancreatic Diseases International 2010年第3期9卷 234-241页

作者： dennis Vaidakis John Karoubalis Theodora Pappa George Piaditis George n Zografos Third Department of Surgery Athens General Hospital Department of Gastroenterology Athens General Hospital Department of Endocrinology Athens General Hospital

BACKGROUnD:Although insulinomas are very rare tumors, they are the most common pancreatic neuroendocrine *** incidence in general population is 1-4 per 1 000 000 yearly but the incidence is higher in autopsy studies. The malignancy of insulinomas is difficult to be predicted on the basis of their histological features,and the current WHO classification has been *** review aimed to summarize classical knowledge with current trends in the diagnosis and treatment of insulinomas. DATA SOURCES:A Medline search using terms'insulinoma', 'treatment'and'neuroendocrine tumors'was conducted. Additional references were sourced from key articles. RESULTS:Surgery is the treatment of choice for insulinoma and has an extremely high success *** treatment is also available but only for patients who are unable or unwilling to undergo surgical *** localization is necessary for planning the surgical *** methods exist for localization of an insulinoma and can be invasive and *** combination of biphasic thin section helical CT and endoscopic ultrasonography(EUS)has an almost 100% sensitivity in localizing *** ultrasound is mandatory to localize intraoperatively these ***-guided fine needle tattoing is an alternative method of localization in case of lack of laparoscopic ultrasound. COnCLUSIOn:Laparoscopic resection for benign insulinomas is the procedure of choice,whereas pancreatectomy is reserved for large,potentially malignant tumors.

关键词： insulinoma pancreas neuroendocrine tumor diagnosis treatment

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Ethene／norbornene copolymerization by[Me2Si（3—^tertBuCp）（n^tertBu）]TiCl2／MAO—catalyst

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Journal of Zhejiang University Science 2003年第2期4卷 121-130页

作者： TRAnPhu-dennis KAMInSKYWalter InstituteofTechnicalandMacromolecularChemistry UniversityofHamburgGermany

?Ethene/norbornene copolymerization by the catalyst system [Me_2Si( 3- tertBuCp)(n tertBu)]TiCl_2/MAO was investigated in detail at 30 ℃, 60℃, and 90℃. A mass flow controller was used in this work to obtain kine tic data and investigate tempera ture's effects on activity, norbornene incorporation, copolymerization parameter , microstructure, glass transition temperature, and molar masses were described. H igh copolymerization values r_E and high alternation are determined. The n umber of isotactic alternating sequences is much higher than that of the syndiot actic alter nating sequences.

关键词： Polymerization Ethene/norbornene copolymers Const rained geometry catalyst Temperature effects.

Routing with Cooperative nodes Using Improved Learning Approaches

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Intelligent Automation & Soft Computing 2023年第3期35卷 2857-2874页

作者： R.Raja n.Satheesh J.Britto dennis C.Raghavendra Department of CSIT CVR College of EngineeringTelanganaIndia Department of Computer Science and Engineering St.Martin’s Engineering CollegeSecunderabadTelanganaIndia Department of Computer Science and Engineering Dhanalakshmi Srinivasan UniversityTrichyTamilnaduIndia CSIT Department CVR College of EngineeringHyderabadIndia

In IoT,routing among the cooperative nodes plays an incredible role in fulﬁlling the network requirements and enhancing system *** eva-luation of optimal routing and related routing parameters over the deployed net-work environment is *** research concentrates on modelling a memory-based routing model with Stacked Long Short Term Memory(s-LSTM)and Bi-directional Long Short Term Memory(b-LSTM).It is used to hold the routing information and random routing to attain superior *** pro-posed model is trained based on the searching and detection mechanisms to com-pute the packet delivery ratio(PDR),end-to-end(E2E)delay,throughput,*** anticipated s-LSTM and b-LSTM model intends to ensure Quality of Service(QoS)even in changing network *** performance of the proposed b-LSTM and s-LSTM is measured by comparing the signiﬁcance of the model with various prevailing ***,the performance is measured with Mean Absolute Error(MAE)and Root Mean Square Error(RMSE)for mea-suring the error rate of the *** prediction of error rate is made with Learn-ing-based Stochastic Gradient Descent(L-SGD).This gradual gradient descent intends to predict the maximal or minimal error through successive *** simulation is performed in a MATLAB 2020a environment,and the model performance is evaluated with diverse *** anticipated model intends to give superior performance in contrast to prevailing approaches.

关键词： Internet of Things(IoT) stacked long short term memory bi-directional long short term memory error rate stochastic gradient descent

A theoretical study of the mechanism of the nucleotidyl transfer reaction catalyzed by yeast RnA polymerase Ⅱ

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Science China Chemistry 2012年第9期55卷 1887-1894页

作者： ZHAnG Yue SALAHUB dennis Key Laboratory for Macromolecular Science of Shaanxi Province School of Chemistry&Materials Shaanxi Normal UniversityXi’an 710062China Institute for Biocomplexity and Informatics University of CalgaryCalgary T2N 1N4Canada Department of Chemistry University of CalgaryCalgary T2N 1N4Canada

The mechanism of the nucleotidyl transfer reaction catalyzed by yeast RnA polymerase I1 has been investigated using molec- ular mechanics and quantum mechanics methods. Molecular dynamics （MD） simulations were carried out using the TIP3 water model and generalized solvent boundary potential （GSBP） by CHARMM based on the X-ray crystal structure. Two models of the ternary elongation complex were constructed based on CHARMM MD calculations. All the species including reactants, transition states, intermediates, and products were optimized using the DFT-PBE method coupled with the basis set DZVP and the auxiliary basis set GEn-A2. Three pathways were explored using the DFT method. The most favorable reaction pathway involves indirect proton migration from the RnA primer 3＇-OH to the oxygen atom of a-phosphate via a solvent water mole- cule, proton rotation from the oxygen atom of a-phosphate to the 13-phosphate side, the RnA primer 3＇-O nucleophilic attack on the a-phosphorus atom, and P-O bond breakage. The corresponding reaction potential profile was obtained. The rate limit- ing step, with a barrier height of 21.5 kcal/mol, is the RnA primer 3＇-0 nucleophilic attack, rather than the commonly consid- ered proton transfer process. A high-resolution crystal structure including crystallographic water molecules is required for fur- ther studies.

关键词： yeast RnA polymerase II nucleotidyl transfer reaction two-metal-ion mechanism two-proton-transfer active center

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Size and shape information serve as labels in the alarm calls of Gunnison＇s prairie dogs Cynomys gunnisoni

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Current Zoology 2012年第5期58卷 741-748页

作者： C. n. SLOBODCHIKOFF William R. BRIGGS Patricia A dennis Anne-Marie C. HODGE Department of Biological Sciences Northern Arizona University Flagstaff AZ 86011 USA Department of Biological Sciences Auburn University Auburn Alabama 36849 USA Present Address: Department of Zoology and Physiology University of Wyoming Laramie WY82071 USA

Some animals have the capacity to produce different alarm calls for terrestrial and aerial predators. However, it is not clear what cognitive processes are involved in generating these calls. One possibility is the position of the predator： Anything on the ground receives a terrestrial predator call, and anything in the air receives an aerial predator call. Another possibility is that animals are able to recognize the physical features of predators and incorporate those into their calls. As a way of elucidating which of these mechanisms plays a primary role in generating the structure of different calls, we performed two field experiments with Gunnison＇s prairie dogs. First, we presented the prairie dogs with a circle, a triangle, and a square, each moving across the colony at the same height and speed. Second, we presented the prairie dogs with two squares of differing sizes. DFA statistics showed that 82.6 percent of calls for the circle and 79.2 percent of the calls for the triangle were correctly classified, and 73.3 percent of the calls for the square were classified as either square or circle. Also, 100 percent of the calls for the larger square and 90 percent of the calls for the smaller square were correctly classified. Because both squares and circles are features of terrestrial predators and triangles are features of aerial predators, our results suggest that prairie dogs might have a cognitive mechanism that labels the abstract shape and size of different predators, rather than the position of the predator [Current Zoology 58 （5）： 741-748, 2012].

关键词： Gunnison's prairie dogs Prairie dogs Alarm calls Referential communication

Inheritance and allelism of morphological traits in eastern redbud (Cercis canadensis L.)

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Horticulture Research 2015年第1期2卷 73-83页

作者： David J.Roberts dennis J.Werner Phillip A.Wadl Robert n.Trigiano Department of Horticultural Science North Carolina State UniversityBox 7609Raleigh27695-7609NCUSA Department of Entomology and Plant Pathology University of Tennessee2505 E.J.Chapman Dr.370 Plant Biotechnology Bldg.Knoxville37996TNUSA

Inheritance of purple,gold,and variegated foliage types,weeping architecture,and double flower was explored in F1,F2,and backcross families resulting from controlled hybridization of eastern redbud(Cercis canadensis L.).Potential allelic relationships were explored when *** analysis in families derived from controlled hybridization of‘Covey’(green leaf)and‘Forest Pansy’(purple leaf)suggest that purple leaf color and weeping architecture are both controlled by single recessive genes,for which the symbols pl1 and wp1 are proposed,*** of gold leaf was explored in families of‘Covey’(green leaf)×‘Hearts of Gold’(gold leaf).Interpretation of inheritance of gold leaf in these families was confounded by the recovery of a leaf color phenotype in the F2 family unlike either ***,data suggested the action of a single locus controlling gold leaf color in‘Hearts of Gold’,and that instability of gold leaf expression may be based on transposable element *** of gold leaf in the F2 families of‘Texas White’[green leaf(*** ***)]×‘Jn2’[gold leaf(The Rising Sun)]did not fit a Mendelian *** of progeny of‘Silver Cloud’and‘Floating Clouds’(both showing white/green leaf variegation)with non-variegated cultivars demonstrated that variegation in‘Silver Cloud’is controlled by a single recessive nuclear gene,while variegation in‘Floating Clouds’is controlled by cytoplasmic *** symbol var1 is proposed for the gene controlling variegation in‘Silver Cloud’.Double flower in progeny derived from‘Flame’(double flower)suggested that double flower is dominant to single flower,and that‘Flame’is heterozygous at the double-flower locus,for which the symbol Df1 is *** studies showed that the gene controlling purple leaf in‘Forest Pansy’is allelic to the purple leaf gene in‘Greswan’and that the gene controlling weeping phenotype in‘Traveller’(*** ***)is non-allelic to the wee

关键词： Inheritance Silver symbol