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Establishment of high frequency shoot regeneration system in Himalayan poplar(Populus ciliata Wall. ex royle) from petiole explants using Thidiazuron cytokinin as plant growth regulator

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Journal of Forestry research 2015年第3期26卷 651-656页

作者： G. Aggarwal A. Gaur d. K. Srivastava department of Biotechnology Dr. Yashwant Singh Parmar University of Horticulture and Forestry NauniSolan 173230 HP India department of Food Technology Desh Bhagat UniversityMandi Gobindgarh 147301 Pb India

Populus species are important resources for industry and in scientific study on biological and agricul- tural systems. Our objective was to enhance the frequency of plant regeneration in Himalayan poplar （Populus ciliata wall. ex royle）. The effect of TdZ alone and in combi- nation with adenine and NAA was studied on the regen- eration potential of petiole explants. The explants were excised from Himalayan poplar plants grown in glass- houses. After surface sterilization the explants were cul- tured on shoot induction medium. High percentage shoot regeneration （86 %） was recorded on MS medium sup- plemented with 0.004 mg L-1 TdZ and 79.7 mg L-1 adenine. The regenerated shoots for elongation and multi- plication were transferred to MS ＋ 0.5 mg L-1 BAP ＋ 0.2 mg L-1 IAA ＋ 0.3 mg L-1 GA3. root re- generation from shoots developed in vitro was observed on MS medium supplemented with 0.10 mg L-1 IBA. Hi- malayan poplar plantlets could be produced within 2 months after acclimatization in a sterile mixture of sand and soil. We developed a high efficiency plant regeneration protocol from petiole explants of P. ciliata.

关键词： In vitro regeneration Petiole explants Growth regulator Thidiazuron Populus ciliata

Investigation of active vibration drilling using acoustic emission and cutting size analysis

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Journal of rock Mechanics and Geotechnical Engineering 2018年第2期10卷 390-401页

作者： Yingjian Xiao Charles Hurich John Molgaard Stephen d.Butt Faculty of Engineering and Applied Science Memorial University of Newfoundland department of Earth Sciences Memorial University of Newfoundland

This paper describes an investigation of active bit vibration on the penetration mechanisms and bit-rock interaction for drilling with a diamond impregnated coring bit. A series of drill-off tests(dOTs) were conducted where the drilling rate-of-penetration(rOP) was measured at a series of step-wise increasing static bit thrusts or weight-on-bits(WOBs). Two active dOTs were conducted by applying 60 Hz axial vibration at the bit-rock interface using an electromagnetic vibrating table mounted underneath the drilling samples, and a passive dOT was conducted where the bit was allowed to vibrate naturally with lower amplitude due to the compliance of the drilling sample mountings. during drilling, an acoustic emission(AE) system was used to record the AE signals generated by the diamond cutter penetration and the cuttings were collected for grain size analysis. The instrumented drilling system recorded the dynamic motions of the bit-rock interface using a laser displacement sensor, a load cell, and an LVdT(linear variable differential transformer) recorded the dynamic WOB and the rOP, respectively. Calibration with the drilling system showed that rotary speed was approximately the same at any given WOB, facilitating comparison of the results at the same WOB. Analysis of the experimental results shows that the rOP of the bit at any given WOB increased with higher amplitude of axial bit-rock vibration, and the drill cuttings increased in size with a higher rOP. Spectral analysis of the AEs indicated that the higher rOP and larger cutting size were correlated with a higher AE energy and a lower AE frequency. This indicated that larger fractures were being created to generate larger cutting size. Overall, these results indicate that a greater magnitude of axial bit-rock vibration produces larger fractures and generates larger cuttings which, at the same rotary speed, results in a higher rOP.

关键词： Active bit vibration diamond coring drilling drill-off tests(dOTs) Acoustic emission(AE) drilling performance Penetration mechanism Cutting size analysis

Microtubule as a Transmission Line for Ionic Currents

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Chinese Physics Letters 2009年第7期26卷 97-99页

作者： IliC d.I. SatariC M.V raleviC N. Faculty of Technical Sciences University of Novi SadTrg D.Obradovica 621000 Novi SadSerbia

We establish a new model for ionic waves along microtubules based on polyelectrolyte features of cylindrical biopolymers. The nonlinear transmission line described by a nonlinear differential equation is obtained with stable kink solution pertinent to the shape of the front of accompanying potential. The localized ionic wave could be used to explain the behavior of microtubules as biomolecular transistors capable of amplifying electrical information in neurons.

关键词： Microtubule Transmission Line Ionic Currents

A Microarray Based Genomic Hybridization Method for Identification of New Genes in Plants：Case Analyses of Arabidopsis and Oryza

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Journal of Integrative Plant Biology 2007年第6期49卷 915-926页

作者： Chuanzhu Fan Maria d. Vibranovski Ying Chen Manyuan Long department of Ecology and Evolution The University of Chicago Chicago IL 60637 USA

To systematically estimate the gene duplication events In closely related species, we have to use comparative genomlc approaches, either through genomlc sequence comparison or comparative genomlc hybridization （CGH）. Given the scarcity of complete genomlc sequences of plant species, in the present study we adopted an array based CGH to Investigate gene duplications In the genus Arabldopsls. Fragment genomlc dNA from four species, namely Arabidopsls thallana, A. lyrata subsp, lyrata, A. lyrata subsp, petraea, and A. halleri, was hybridized to Affymetrlx （Santa Clara, CA, USA） tiling arrays that are designed from the genomlc sequences of A. thallana. Pairwlse comparisons of signal intensity were made to infer the potential duplicated candidates along each phylogenetic branch. Ninety-four potential candidates of gene duplication along the genus were Identified. Among them, the majority （69 of 94） were A. thallana lineage specific. This result indicates that the array based CGH approach may be used to Identify candidates of duplication In other plant genera containing closely related species, such as Oryza, particularly for the AA genome species. We compared the degree of gene duplication through retrotransposon between O. satlva and A. thallana and found a strikingly higher number of chimera retroposed genes In rice. The higher rate of gene duplication through retroposltlon and other mechanisms may Indicate that the grass species Is able to adapt to more diverse environments.

关键词： Arabidopsis comparative genomic hybridization microarray new genes Oryza retroposition.

deep Feature Extraction and Feature Fusion for Bi-Temporal Satellite Image Classification

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Computers, Materials & Continua 2021年第1期66卷 373-388页

作者： Anju Asokan Bogdan Patrut dana danciulescu d.Jude Hemanth department of ECE Karunya Institute of Technology and SciencesCoimbatoreIndia department of Computer Science Alexandru Ioan Cuza University of la?ila?iRomania department of Computer Science University of CraiovoCraiovoRomania

Multispectral images contain a large amount of spatial and spectral data which are effective in identifying change *** feature extraction is important for multispectral image classification and is evolving as an interesting research area in change ***,many deep learning framework based approaches do not consider both spatial and textural details into *** order to handle this issue,a Convolutional Neural Network(CNN)based multi-feature extraction and fusion is introduced which considers both spatial and textural *** method uses CNN to extract the spatio-spectral features from individual channels and fuse them with the textural *** the fused image is classified into change and unchanged *** presence of mixed pixels in the bitemporal satellite images affect the classification accuracy due to the misclassification *** proposed method was compared with six state-of-theart change detection methods and *** main highlight of this method is that by taking into account the spatio-spectral and textural information in the input channels,the mixed pixel problem is *** indicate the effectiveness of this method and demonstrate that it possesses low misclassification errors,higher overall accuracy and kappa coefficient.

关键词： remote sensing convolutional neural network deep learning multispectral bitemporal change detection

Some Characteristics of Cumulus Convection over the Tibetan Plateau

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Advances in Atmospheric Sciences 1990年第1期7卷 87-97页

作者：段廷扬 Elmar r.reiter Chengdu Institute of Meteorology Chengdu 610041 Sichuan Province Center lor Cybernetic Communication research Colorado Slate University Fort Collins CO.80523 U. S. A.he diagnostic model of the cumulus convection proposed by Yanai et al. (1973) was applied to the atmosphere over the Tibetan Plateau and used to estimate the vertical mass flux entrainment and detrainment excess temperature and moisture liquid water content and condensation and precipitation rates of highland cloud clusters. The results illustrated that in clouds over the Tibetan Plateau the water vapor condensation rate liquid water content and efficiency of the rain generation process are less than those in the tropics (represented by the Marshall Islands region). Therefore the condensational latent heat released over the Tibetan Plateau overall is much smaller than that in the tropics. The water vapor and liquid water detrainment from shallow nonprecipitating cumulus clouds and their entrainment into deep cumulus clouds serve as a growing mechanism for the deep precipitating cumulus towers over the Tibetan Plateau. It should be noted that there is a stronger detrainment of liquid water from cumulus clouds and a stronger re-evaporation rate in environment. The process of the condensation-detrainment-re-evaporation-cnlrainmcnt is repeatedly in progress. It would play an important role in maintaining of cumulus convection on the condition that the supply of moisture is not plentiful over the Tibetan Plateau.The analyses also showed that the cloud mass flux Mc over the Tibetan Plateau is less and the large-scale average upward motion is much less than those over the Marshall Islands. Stronger compensating downward motion in the cloud environment over the Tibetan Plateau responsible for the area's strong environmental heating rate Was revealed and would link to the stability of the South Asian High in summer.

The diagnostic model of the cumulus convection proposed by Yanai et al. (1973) was applied to the atmosphere over the Tibetan Plateau, and used to estimate the vertical mass flux, entrainment and detrainment, excess temperature and moisture, liquid water content, and condensation and precipitation rates of highland cloud clusters. The results illustrated that in clouds over the Tibetan Plateau, the water vapor condensation rate, liquid water content, and efficiency of the rain generation process are less than those in the tropics (represented by the Marshall Islands region). Therefore, the condensational latent heat released over the Tibetan Plateau, overall, is much smaller than that in the tropics. The water vapor and liquid water detrainment from shallow nonprecipitating cumulus clouds, and their entrainment into deep cumulus clouds, serve as a growing mechanism for the deep precipitating cumulus towers over the Tibetan Plateau. It should be noted that there is a stronger detrainment of liquid water from cumulus clouds and a stronger re-evaporation rate in environment. The process of the condensation-detrainment-re-evaporation-cnlrainmcnt is repeatedly in progress. It would play an important role in maintaining of cumulus convection on the condition that the supply of moisture is not plentiful over the Tibetan *** analyses also showed that the cloud mass flux Mc over the Tibetan Plateau is less, and the large-scale average upward motion is much less than those over the Marshall Islands. Stronger compensating downward motion in the cloud environment over the Tibetan Plateau, responsible for the area's strong environmental heating rate Was revealed, and would link to the stability of the South Asian High in summer.

关键词： Some Characteristics of Cumulus Convection over the Tibetan Plateau over

On the Characterizability of the Automorphism Groups of Sporadic Simple Groups by Their Element Orders

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Acta Mathematicae Applicatae Sinica 2004年第4期 653-662页

作者： A.r.MOGHAddAMFAr A.r.ZOKAYI M.r.dArAFSHEH department of Mathematics Faculty of Science K.N.Toosi University of Technology P.O.Box 16315-1618 Tehran Iran department of Mathematics Faculty of Science K.N.Toosi University of Technology P.O.Box 16315-1618 Tehran Iran department of Mathematics and Computer Sciences Faculty of Science University of Tehran Tehran Iran

For G a finite group,πe（G） denotes the set of orders of elements in *** Ω is a subsetof the set of natural numbers,h（Ω） stands for the number of isomorphism classes of finite groups withthe stone set Ω of element *** say that G is k-distinguishable if h(πe（G）)=krwiseG is called ***,a 1-distinguishable group is called a characterizable *** shown that if M is a sporadic simple group different from M12,M22,J2,He,Suz,McL and O'N,then Aut（M） is characterizable by its element *** is also proved that if M is isomorphic toM12,M22,He,Suz or O'N,then h(πe(Aut（M）))∈{1,∞}.

关键词： Automorphism group Element orders Prime graph Sporadic simple groups

SINGLE MACHINE SCHEdULING WITH CONTrOLLABLE PrOCESSING TIMES ANd COMPrESSION COSTS （PArT I：EQUAL TIMES ANd COSTS）

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Applied Mathematics(A Journal of Chinese Universities) 1998年第4期13卷 417-426页

作者： TANGGUOCHUN FOULdS,L.r. departmentofManagement ShanghaiSecondPolytechncUniversityShanghai200002. departmentofManagementSystems UniversityofWaikatoHamiltonNewZealand

Abstract Most papers in scheduling research have treated individual job processing times as fixed parameters. However, in many practical situations, a manager may control processing time by reallocating resources. In this paper, authors consider a machine scheduling problem with controllable processing times. In the first part of this paper, a special case where the processing times and compression costs are uniform among jobs is discussed. Theoretical results are derived that aid in developing an O(n 2) algorithm to slove the problem optimally. In the second part of this paper, authors generalize the discussion to general case. An effective heuristic to the general problem will be presented.

关键词： Machine scheduling problems controllable processing times uniform compression timeand cost dominance set lateness crash activities polynomial time algorithm

Fuzzy Based Adaptive Clustering to Improve the Lifetime of Wireless Sensor Network

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China Communications 2019年第12期16卷 56-71页

作者： d.Uma Maheswari S.Sudha M.Meenalochani National Institute of Technology

The objective of the recently proposed fuzzy based hierarchical routing protocol F-SCH is to improve the lifetime of a Wireless Sensor Network. Though the performance of F-SCH is better than LEACH, the randomness in CH selection inhibits it from attaining enhanced lifetime. CBCH ensures maximum network lifetime when CH is close to the centroid of the cluster. However, for a widely distributed network, CBCH results in small sized clusters increasing the inter cluster communication cost. Hence, with an objective to enhance the network lifetime, a fuzzy based two-level hierarchical routing protocol is proposed. The novelty of the proposal lies in identification of appropriate parameters used in Cluster Head and Super Cluster Head selection. Experiments for different network scenarios are performed through both simulation and hardware to validate the proposal. The performance of the network is evaluated in terms of Node death. The proposal is compared with F-SCH and the results reveal the efficacy of the proposal in enhancing the lifetime of network.

关键词： hierarchical routing node degree centrality network lifetime fuzzy wireless sensor networks