Phylogenetic grouping and identification of Rhizobium isolates on the basis of random amplified polymorphic DNA profiles

1993 ◽  
Vol 39 (7) ◽  
pp. 665-673 ◽  
Author(s):  
John J. Dooley ◽  
Stephen P. Harrison ◽  
Lance R. Mytton ◽  
Malcolm Dye ◽  
Ann Cresswell ◽  
...  
Keyword(s):  
Rhizobium Leguminosarum ◽  
Rhizobium Meliloti ◽  
Random Amplified Polymorphic Dna ◽  
Dna Amplification ◽  
Distinct Group ◽  
Principal Coordinate Analysis ◽  
The Other ◽  
Phylogenetic Grouping ◽  
Dna Profiles ◽  
Selection Of

Through the use of a single, random 15mer as a primer, between 1 and 12 DNA amplification products were obtained per strain from a selection of 84 Rhizobium and Bradyrhizobium isolates. A principal-coordinate analysis was used to analyse the resulting amplified DNA profiles and it was possible to assign isolates to specific groupings. Within the species Rhizobium leguminosarum, the biovar phaseoli formed a distinct group from the other biovars of the species, viciae and trifolii, which grouped together. Isolates of Rhizobium meliloti and Bradyrhizobium species formed their own clear, specific groups. Although it was possible to identify individual isolates on the basis of differences in their amplified DNA profiles, there was evidence that some amplified segments were conserved among individuals at the biovar and species levels.Key words: Rhizobium, DNA amplification, random primers.

A stydy of Rhizobium leguminosarum biovar trifolii populations from soil extracts using randomly amplified polymorphic DNA profiles

1995 ◽  
Vol 41 (4-5) ◽  
pp. 336-344 ◽  
Author(s):  
Malcolm Dye ◽  
Leif Sket ◽  
Lance R. Mytton ◽  
Ann Cresswell ◽  
Stephen P. Harrison ◽  
...  
Keyword(s):  
Rhizobium Leguminosarum ◽  
Rapd Analysis ◽  
Dna Amplification ◽  
Differential Centrifugation ◽  
Randomly Amplified Polymorphic Dna ◽  
Phenotypic Characteristics ◽  
Soil Extracts ◽  
Dna Profiles ◽  
Rapd Fragment ◽  
Rhizobium Leguminosarum Biovar Trifolii

This study has shown that isolates of Rhizobium leguminosarum biovar trifolii can be grouped on the basis of their randomly amplified polymorphic DNA (RAPD) fragment patterns. Evidence is presented that these groups are not entirely arbitrary but are consistent with other genetic and phenotypic characteristics. RAPD analysis has been used to assess the efficiency of a dispersion and differential centrifugation procedure used to extract bacteria from soil. Whilst the major groups of Rhizobium isolates in soils were also found in the extracts, some of the others were missing. This is also reflected in the finding, made by measuring abundance of organisms, that as many Rhizobium isolates are left in the residue as appear in the supernatant; more dispersion steps, possibly with different dispersants, are needed to maximize extraction. The technique has also demonstrated that dispersing soil by simply shaking it in water not only underestimates the numbers of Rhizobium isolates present but also masks much of their diversity.Key words: Rhizobium, DNA amplification, random primers, bacterial extraction.

scholarly journals 678 PB 186 RAPD GENETIC MARKERS FOR CHARACTERIZATION OF MUSA GENETIC RESOURCES

HortScience ◽  
1994 ◽  
Vol 29 (5) ◽  
pp. 530a-530
Author(s):  
R.L. Jarret ◽  
K.V. Bhat
Keyword(s):  
Genetic Markers ◽  
Size Range ◽  
Rapd Analysis ◽  
Random Amplified Polymorphic Dna ◽  
Dna Amplification ◽  
Principal Coordinate Analysis ◽  
Phenetic Analysis ◽  
Similarity Coefficients ◽  
Primer Sequence

Fifty-seven accessions of Musa including cultivated clones Of 6 genomic groups (AA, AB, AAA, AAB, ABB, ABBB), M. balbisiana (BB), M. acuminata ssp. banksii (AA), M. acuminata ssp. malaccensis (AA) and M. velutina were examined for random amplified polymorphic DNA (RAPD) genetic markers using PCR with sixty 10-mer random primers. Forty-nine of 60 tested primers gave reproducible DNA amplification patterns. The number of bands resolved per amplification was primer dependent and varied from 1 to a maximum of 24. The size range of the amolification products also differed with the select& primer sequence/genotype and ranged from 0.29 to 3.0 kb. RAPD data were used to generate Jaccard's similarity coefficients which were analyzed phenetically. Phenetic analysis separated clones into distinct groupings that were in agreement with clusterings revealed when data were subsequently analyzed by principal coordinate analysis (PCO). In both the phenetic and the PCO analyses, previously unclassified cultivars grouped with cultivars previously classified for their genomic group based on morphological keys. The implications of RAPD analysis for Musa germplasm classification, clonal identification, and management are discussed.

scholarly journals New Rhizobium leguminosarum bv. trifolii isolates: Evaluation of competitiveness for clover nodule occupancy

2011 ◽  
Vol 52 (No. 10) ◽  
pp. 441-448 ◽  
Author(s):  
T. Šimon ◽  
J. Salava
Keyword(s):  
Nitrogen Fixation ◽  
Rhizobium Leguminosarum ◽  
Random Amplified Polymorphic Dna ◽  
The Other ◽  
Pot Experiment ◽  
Nodule Occupancy ◽  
Inoculum Level ◽  
Highly Efficient ◽  
Inoculum Dose ◽  
Beginning Of Flowering

An interrelationship between introduced and indigenous rhizobia focused on their competitiveness in nodulation was evaluated in a soil pot experiment. Clover seeds were inoculated by six different gradual concentrations of inoculum of two effective Rhizobium leguminosarum bv. trifolii isolates (inoculation strains 1/2 and 14/2). At the beginning of flowering, clover plants were removed from the pots, and nodules from each pot representing different degrees of inoculum level were taken for reisolate cultivation. The PCR technique was used for the identification of rhizobial reisolates, random amplified polymorphic DNA product patterns were acquired and analysed. Nodule occupation by inoculation strains or indigenous Rhizobium leguminosarum bv. trifolii strains was assessed by comparing the number of nodules formed by inoculation or indigenous strains and inoculation strains competitiveness was calculated. Nodule occupancy by the inoculation strain 1/2 increased sharply with the increase in inoculum dose, whereas in inoculation strain 14/2 more nodules were formed gradually starting from low inoculum level. Competitiveness of inoculation strain 1/2 was calculated as low and was documented by an absence of nodule occupancy in four inoculation levels. On the other hand, competitiveness of the inoculation strain 14/2 was considerably higher, and even in low inoculum dose this strain was more competitive than native rhizobia. Although both the inoculation strains 1/2 and 14/2 were found highly efficient in nitrogen fixation, only the strain 14/2 was able to manifest this characteristic due to the higher competitiveness when applied in lower doses.

scholarly journals Molecular Diversity Analysis in Cotton (Gossypium hirsutum L.) Using RAPD Markers

2020 ◽  
pp. 33-44
Author(s):  
Md. Abdul Wahab ◽  
Shamim Ara Sumi ◽  
Absana Islam ◽  
M. E. Houqe
Keyword(s):  
Gossypium Hirsutum ◽  
Rapd Markers ◽  
Molecular Diversity ◽  
Random Amplified Polymorphic Dna ◽  
Research Work ◽  
Dna Amplification ◽  
Gossypium Hirsutum L ◽  
Average Value ◽  
Cotton Genotypes ◽  
Selection Of

Cotton (Gossypium hirsutum L) is considered as major textile fiber around the world. This research aimed to analyze the molecular diversity among 9 cotton genotypes collected from Cotton Development Board, Bangladesh using the 7 Random Amplified Polymorphic DNA (RAPD) markers. Some total of 18 DNA bands were obtained and among them, 13 were polymorphic bands. The range of DNA amplification varied from 180 to 800 bp. The percentage of polymorphism was about 50.71. Genetic diversity ranged from 0.22 to 0.44 with an average value of 0.34. Nei’s genetic distance ranging from 0.1667 to 0.6667 and most importantly PIC value ranged from 0.18 to 0.35 with an average value of 0.27. The PIC value indicated that most of the studied cotton genotypes were moderately diversified and homogenous as well as no heterozygosity found. A dendrogram indicating the relative genetic similarity of the Bangladeshi cotton genotypes was constructed which followed in two major clusters (A and B) among the studied material. The Cotton Development Board (CDB), Bangladesh committed to working on cotton improvement and this investigation will be helpful for the selection of diversified genotypes in varietal improvement in cotton. The output of this research will be a baseline for future molecular research work on cotton genotypes in Bangladesh.

Note on Selection of Coordinate Systems for Geodynamics

1975 ◽  
Vol 26 ◽  
pp. 395-407
Author(s):  
S. Henriksen
Keyword(s):  
Sea Level ◽  
The Other ◽  
Coordinate Systems ◽  
Mean Sea Level ◽  
The Earth ◽  
The One ◽  
Static Systems ◽  
Selection Of

The first question to be answered, in seeking coordinate systems for geodynamics, is: what is geodynamics? The answer is, of course, that geodynamics is that part of geophysics which is concerned with movements of the Earth, as opposed to geostatics which is the physics of the stationary Earth. But as far as we know, there is no stationary Earth – epur sic monere. So geodynamics is actually coextensive with geophysics, and coordinate systems suitable for the one should be suitable for the other. At the present time, there are not many coordinate systems, if any, that can be identified with a static Earth. Certainly the only coordinate of aeronomic (atmospheric) interest is the height, and this is usually either as geodynamic height or as pressure. In oceanology, the most important coordinate is depth, and this, like heights in the atmosphere, is expressed as metric depth from mean sea level, as geodynamic depth, or as pressure. Only for the earth do we find “static” systems in use, ana even here there is real question as to whether the systems are dynamic or static. So it would seem that our answer to the question, of what kind, of coordinate systems are we seeking, must be that we are looking for the same systems as are used in geophysics, and these systems are dynamic in nature already – that is, their definition involvestime.

INTERFERENSI GRAMATIKAL DALAM KUMPULAN CERPEN BIARKAN AKU MEMULAI KARYA NURUL F. HUDA

2019 ◽  
Vol 1 (01) ◽  
pp. 16-23
Author(s):  
Zimmatul Liviana
Keyword(s):  
Short Stories ◽  
Data Collection ◽  
Qualitative Method ◽  
Language Variation ◽  
The Other ◽  
Qualitative Descriptive ◽  
Ofthe Object ◽  
Selection Of ◽  
Descriptive Qualitative

The research grammatical interference in a collection ofshort stories Biarkan Aku Memula iwork Nurul F. Hudaisa collection ofshort storiesset in the back that Is start work Let Nurul F. Huda contains many grammatical interference.The problem of this   study were(1)how   the various morphologi calinterference containedin   a   collection of short stories Biarkan Aku Memulai work Nurul F. Huda. (2)how the various syntactic interference contained in a collection of short stories Biarkan Aku Memulai work Nurul F. Huda. The purposeof this studyis to describe the morphological and         Syntactic interference contained in a collection of short stories Biarkan Aku Memulai work Nurul F. Huda. Sociolinguistics is the study of language variation and use in society. Interference is the event of the use of language elements of one into the other language elements that occur in the speakers themselves. This research uses descriptive qualitative method because to describe the actual realityin order to obtainan accurateand objective. Qualitative descriptive methods were used to analyzethe elements ofa word orphrase that incorporated elements of other languages with the analysis and description of the formulation of the problem is the answer. Data collection techniques using observation techniques, the determination ofthe object of research, the selection of short stories.Based on the analysis of the data in this study can be found that there are six forms of interference morphology, namely (1) the prefix nasal N-sound, (2) the addition of the suffix, (3) the exchange prefix, (4) exchange suffixes, (5) exchange konfiks, (6) removal affixes. While the syntactic interference only on the words and phrases in a sentence. The results of the study it can be concluded that the interference morphology more common than syntactic interference.

The Propaganda Feedback Loop

2018 ◽  
Author(s):  
Yochai Benkler ◽  
Robert Faris ◽  
Hal Roberts
Keyword(s):  
Case Studies ◽  
Feedback Loop ◽  
The Other ◽  
Hillary Clinton ◽  
Donald Trump ◽  
The Public ◽  
False Reporting ◽  
Media Ecosystem ◽  
Crowd Out ◽  
Selection Of

This chapter presents a model of the interaction of media outlets, politicians, and the public with an emphasis on the tension between truth-seeking and narratives that confirm partisan identities. This model is used to describe the emergence and mechanics of an insular media ecosystem and how two fundamentally different media ecosystems can coexist. In one, false narratives that reinforce partisan identity not only flourish, but crowd-out true narratives even when these are presented by leading insiders. In the other, false narratives are tested, confronted, and contained by diverse outlets and actors operating in a truth-oriented norms dynamic. Two case studies are analyzed: the first focuses on false reporting on a selection of television networks; the second looks at parallel but politically divergent false rumors—an allegation that Donald Trump raped a 13-yearold and allegations tying Hillary Clinton to pedophilia—and tracks the amplification and resistance these stories faced.

scholarly journals Design Concepts for NiTiNOL Wires to Function as a Sensor

2021 ◽  
Author(s):  
D. Josephine Selvarani Ruth
Keyword(s):  
Shape Memory Alloy ◽  
Electrical Resistance ◽  
Nickel Titanium ◽  
The Other ◽  
Sensing Element ◽  
Proper Selection ◽  
Design Concepts ◽  
Mechanical Element ◽  
Selection Of ◽  
Inverse Hysteresis

AbstractNickel Titanium Naval Ordinance Laboratory (NiTiNOL) is widely called as a shape memory alloy (SMA), a class of nonlinear smart material inherited with the functionally programmed property of varying electrical resistance during the transformation enabling to be positioned as a sensing element. The major challenge to instrument the SMA wires is to suppress the wires’ nonlinearity by proper selection of two important factors. The first factor is influenced by the mechanical biasing element and the other is to identify the sensing current for the sensing device (SMA wires + biasing). This paper focuses on developing SMA wires for sensing in different orientation types and configurations by removing the non-linearity in the system’s output by introducing inverse hysteresis to the wires through the passive mechanical element.

scholarly journals An Algorithm for Choosing the Optimal Number of Muscle Synergies during Walking

Sensors ◽  
2021 ◽  
Vol 21 (10) ◽  
pp. 3311
Author(s):  
Riccardo Ballarini ◽  
Marco Ghislieri ◽  
Marco Knaflitz ◽  
Valentina Agostini
Keyword(s):  
Motor Task ◽  
Optimal Number ◽  
The Other ◽  
Simulated Dataset ◽  
Muscle Synergies ◽  
Mean Square ◽  
Real Dataset ◽  
Traditional Approaches ◽  
Selection Of ◽  
Semg Signals

In motor control studies, the 90% thresholding of variance accounted for (VAF) is the classical way of selecting the number of muscle synergies expressed during a motor task. However, the adoption of an arbitrary cut-off has evident drawbacks. The aim of this work is to describe and validate an algorithm for choosing the optimal number of muscle synergies (ChoOSyn), which can overcome the limitations of VAF-based methods. The proposed algorithm is built considering the following principles: (1) muscle synergies should be highly consistent during the various motor task epochs (i.e., remaining stable in time), (2) muscle synergies should constitute a base with low intra-level similarity (i.e., to obtain information-rich synergies, avoiding redundancy). The algorithm performances were evaluated against traditional approaches (threshold-VAF at 90% and 95%, elbow-VAF and plateau-VAF), using both a simulated dataset and a real dataset of 20 subjects. The performance evaluation was carried out by analyzing muscle synergies extracted from surface electromyographic (sEMG) signals collected during walking tasks lasting 5 min. On the simulated dataset, ChoOSyn showed comparable performances compared to VAF-based methods, while, in the real dataset, it clearly outperformed the other methods, in terms of the fraction of correct classifications, mean error (ME), and root mean square error (RMSE). The proposed approach may be beneficial to standardize the selection of the number of muscle synergies between different research laboratories, independent of arbitrary thresholds.

Romance and Latin approaches to word structure features

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Elisabeth Gibert-Sotelo ◽  
Isabel Pujol Payet
Keyword(s):  
The Other ◽  
Special Issue ◽  
Valuable Contribution ◽  
Field Of Study ◽  
Word Structure ◽  
New Approaches ◽  
Theoretical Approaches ◽  
Special Collection ◽  
Introductory Paper ◽  
Selection Of

Abstract The interest in morphology and its interaction with the other grammatical components has increased in the last twenty years, with new approaches coming into stage so as to get more accurate analyses of the processes involved in morphological construal. This special issue is a valuable contribution to this field of study. It gathers a selection of five papers from the Morphology and Syntax workshop (University of Girona, July 2017) which, on the basis of Romance and Latin phenomena, discuss word structure and its decomposition into hierarchies of features. Even though the papers share a compositional view of lexical items, they adopt different formal theoretical approaches to the lexicon-syntax interface, thus showing the benefit of bearing in mind the possibilities that each framework provides. This introductory paper serves as a guide for the readers of this special collection and offers an overview of the topics dealt in each contribution.

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