scholarly journals ANALYSIS OF ALLEAL DIVERSITY OF THE NODX GENE IN BACTERIA OF THE SPECIES RHIZOBIUM LEGUMINOSARUM, BEAN SYMBIONTS TRIFOLIUM AND VAVILOVIA

2020 ◽  
Vol 2 (4(73)) ◽  
pp. 18-21
Author(s):  
T.S. Aksenova ◽  
A.K. Kimeklis

Rhizobium leguminosarumspecies is divided into two biovars according to the host plant which they have the ability to nodulate: viciaewith legumes from the tribe Fabeae, trifoliiwith legumes of the genus Trifolium. However, a separate group of symbionts of the relict plant Vavilovia formosaseparates from biovar viciae, demonstrating ancestral features of genomes. In this study, we compare the selection of the Vaviloviaand Trifoliumsymbionts in order to identify common patterns in the structure of symbiotic genes. The results show that, both these rhizobia groups share several ancestral features. The data obtained suggest that the symbionts Vaviloviaand Trifoliumcan also show some resemblance to the common ancestor of the species R. leguminosarum, which existed before the division of the species into viciaeand trifoliibiovars

Archaea ◽  
2013 ◽  
Vol 2013 ◽  
pp. 1-18 ◽  
Author(s):  
Patrick Forterre

It is often assumed that eukarya originated from archaea. This view has been recently supported by phylogenetic analyses in which eukarya are nested within archaea. Here, I argue that these analyses are not reliable, and I critically discuss archaeal ancestor scenarios, as well as fusion scenarios for the origin of eukaryotes. Based on recognized evolutionary trends toward reduction in archaea and toward complexity in eukarya, I suggest that their last common ancestor was more complex than modern archaea but simpler than modern eukaryotes (the bug in-between scenario). I propose that the ancestors of archaea (and bacteria) escaped protoeukaryotic predators by invading high temperature biotopes, triggering their reductive evolution toward the “prokaryotic” phenotype (the thermoreduction hypothesis). Intriguingly, whereas archaea and eukarya share many basic features at the molecular level, the archaeal mobilome resembles more the bacterial than the eukaryotic one. I suggest that selection of different parts of the ancestral virosphere at the onset of the three domains played a critical role in shaping their respective biology. Eukarya probably evolved toward complexity with the help of retroviruses and large DNA viruses, whereas similar selection pressure (thermoreduction) could explain why the archaeal and bacterial mobilomes somehow resemble each other.


1935 ◽  
Vol 1 ◽  
pp. 108-114
Author(s):  
W. J. Hemp

The case here presented is in a sense ‘special pleading’ and does not profess to give a complete explanation of the very complicated plans provided by the few long barrows and chambered cairns which have been excavated with any degree of care and completeness.It may, in fact, be likened to an attempt to prove a single line of descent in a complicated pedigree; but, in my opinion the line is the principal one leading up to the common ancestor of a vast family of cousins of different degree.One difficulty is the selection of a starting point in the family tree (to continue the metaphor); Mr O. G. S. Crawford would take the pedigree back to the house, a thesis it is much to be hoped that he will develop. I would, however, enter the caveat that in the particular case he cites the possibility of a reversal of the process of development should be considered. In a paper read to the Society of Antiquaries Mr Stuart Piggott suggested that an elongated chamber found by Mortimer under a round barrow at Kemp Howe was a house converted into a tomb. I would rather believe it to have been constructed for a burial chamber, and claim it as another link in the line of evolution from burial cave to barrow which I am trying to establish.


2017 ◽  
Author(s):  
Trevor Bedford ◽  
Richard A. Neher

AbstractThis report details current seasonal influenza circulation patterns as of Sep 2017 and makes projections up to Sep 2018 to coincide with selection of the 2018 Southern Hemisphere vaccine strain. This is not meant as a comprehensive report, but is instead intended as particular observations that we’ve made that may be of relevance. Please also note that observed patterns reflect the GISAID database and may not be entirely representative of underlying dynamics. All analyses are based on the nextflu pipeline [1] with continual updates posted to nextflu.org.A/H3N2H3N2 continues to diversify with many coexisting clades, all of which carry several amino acid mutations at previously characterized epitope sites. The majority of viruses fall into the 3c2.a clade which has been dominating globally for >3 years, but 3c3.a viruses continue to persist. The common ancestor of circulating H3N2 viruses is now more than 5 years old, which is rare for H3N2. Despite extensive genetic diversity, serological assays suggest limited, but non-zero, antigenic evolution. We expect multiple competing clades within 3c2.a to persist into the future with no clear immediate winner.A/H1N1pdmA clade comprising mutations S74R and I295V has recently risen to >60% global frequency. Although it shows no antigenic distinction by ferret HI data, the rapidity of its rise suggests a selective origin.B/VicA clade with a two amino acid deletion 162-/163-has altered serological properties and is increasing in frequency, albeit slowly. Two other clades (carrying mutations K209N and V87A/I175V) have increased in frequency moderately.B/YamA clade comprising M251V within clade 3 viruses continues to dominate. The is little genetic differentiation within this clade and no evidence of antigenic evolution.


Metahumaniora ◽  
2017 ◽  
Vol 7 (3) ◽  
pp. 354
Author(s):  
Ferli Hasanah

ABSTRAKGramatika pada setiap bahasa memiliki kekhasannya masing-masing.Mahasiswa Program Studi Sastra Perancis tahun pertama sebagai pembelajar pemulasering mengalami kesulitan dalam memahami gramatika bahasa. Kesulitan mereka tidakterlepas dari perbedaan-perbedaan mendasar pada struktur bahasa Indonesia sebagaibahasa ibu mereka dan bahasa Perancis yang tengah dipelajari. Penelitian ini dilaksanakandengan tujuan untuk mengetahui hambatan yang dimiliki mahasiswa pembelajar pemuladi Program Studi Sastra Perancis Universitas Padjadjaran dalam memahami gramatikabahasa Perancis. Metode yang digunakan dalam penelitian ini adalah metode simak dancatat. Hasil analisis ini menunjukkan bahwa kesalahan-kesalahan yang umum dilakukanpembelajar pemula ada pada penggunaan accent, konjugasi verba, partikel défini maupunindéfini, accord penanda feminin atau jamak, serta pemilihan preposisi.Kata kunci: gramatika, bahasa Perancis, konjugasiABST RACTThe grammar in every language has its own particularities. French literaturestudents in the first year as a beginner learners often have problem in understandingFrench grammar which is frequently considered difficult. Their struggle is inseparablefrom the fundamental differences between Indonesian structure as their mother tongueand the French language which being studied. This research aims to know the obstaclesof the students of beginner learners in the French Literature of Padjadjaran university inunderstanding the basic French grammar. The method used in this research is referringand taking notes method. The results of the analysis shows that the common mistakes oflearners are in the use of accents, verb conjugations, particles défini or indéfini, markeraccord feminine or plural, and the selection of prepositions.Keywords: grammar, French, conjugation


2020 ◽  
Vol 3 (152) ◽  
pp. 92-99
Author(s):  
S. M. Geiko ◽  
◽  
O. D. Lauta

The article provides a philosophical analysis of the tropological theory of the history of H. White. The researcher claims that history is a specific kind of literature, and the historical works is the connection of a certain set of research and narrative operations. The first type of operation answers the question of why the event happened this way and not the other. The second operation is the social description, the narrative of events, the intellectual act of organizing the actual material. According to H. White, this is where the set of ideas and preferences of the researcher begin to work, mainly of a literary and historical nature. Explanations are the main mechanism that becomes the common thread of the narrative. The are implemented through using plot (romantic, satire, comic and tragic) and trope systems – the main stylistic forms of text organization (metaphor, metonymy, synecdoche, irony). The latter decisively influenced for result of the work historians. Historiographical style follows the tropological model, the selection of which is determined by the historian’s individual language practice. When the choice is made, the imagination is ready to create a narrative. Therefore, the historical understanding, according to H. White, can only be tropological. H. White proposes a new methodology for historical research. During the discourse, adequate speech is created to analyze historical phenomena, which the philosopher defines as prefigurative tropological movement. This is how history is revealed through the art of anthropology. Thus, H. White’s tropical history theory offers modern science f meaningful and metatheoretically significant. The structure of concepts on which the classification of historiographical styles can be based and the predictive function of philosophy regarding historical knowledge can be refined.


2020 ◽  
Vol 62 ◽  
pp. 32-38
Author(s):  
E. A. Dolmatov ◽  
R. B. Borzayev ◽  
A. N. Shaipov

The results of the study of the duration of the juvenile period of indigenous Chechen willow leaf pear genotypes (Pyrus salicifolia Pall.) are given in connection with the acceleration of the breeding process and the use of selected forms in pear breeding for high precocity. The studies were carried out in 2016-2019 at OOO “Orchards of Chechnya” in accordance with the Agreement on creative cooperation with the Russian Research Institute of Fruit Crop Breeding. The work was carried out in accordance with generally accepted programs and methods. The objects of the study were one-year and two-year-old pear seedlings obtained from sowing seeds of selected dwarf and low-growing local Chechen forms of willow pear (P. salicifolia Pall.), laying fruit buds on annual growths and seedlings of Caucasian pear (P. caucasica Fed.), 20 500 pcs. of each specie. The aim of the research was to study the potential of precocity of willow pear seedlings and to reveal of selected forms with the greatest degree of this trait. Stratified seeds were sown in the sowing department of the OOO “Orchards of Chechnya” production nursery in April, 2017. The seedlings were grown according to the common technology in dryland conditions on the plot with chestnut soil. The first fl owering of plants was noted in the spring, 2019. As a result of the research, for the first time on a large number of the experimental material it was found that in the off spring of the indigenous Chechen willow leaf pear genotypes, the selection of a little more than 2% of seedlings with a very short juvenile period (2 years) was possible. They are of great interest in accelerating the breeding process and in the selection of new pear varieties with high precocity. 20 willow leaf pear genotypes were selected for the further use in breeding for high precocity and as sources of the trait of short juvenile period.


1983 ◽  
Vol 38 (5-6) ◽  
pp. 501-504 ◽  
Author(s):  
Mária Ujhelyi

Seryl tRNA (anticodon GCU) from mammalian mito­chondria shows in comparison to other mitochondrial tRNAs additional special features differing from the generalized tRNA model. When arranged in the tradi­tional cloverleaf form, eight bases fall within the TΨC loop, and the entire dihydrouridine loop is lacking. This seryl tRNA molecule is therefore shorter than other tRNAs. It was originally thought to represent a mito­chondrial analogon of 5 S rRNA and its precise classifica­tion is still disputed. The present studies suggest that this mitochondrial tRNA represents a fossil molecule which is related to the common ancestor of the present tRNA and 5 S rRNA molecules.


2013 ◽  
Vol 2013 ◽  
pp. 1-5 ◽  
Author(s):  
Jeffrey S. Prince ◽  
Paul Micah Johnson

The ultrastructure of the digestive gland of several sea hare species that produce different colored ink (Aplysia californicaproduces purple ink,A. julianawhite ink,A. parvulaboth white and purple ink, whileDolabrifera dolabriferaproduces no ink at all) was compared to determine the digestive gland’s role in the diet-derived ink production process. Rhodoplast digestive cells and their digestive vacuoles, the site of digestion of red algal chloroplast (i.e., rhodoplast) inA. californica, were present and had a similar ultrastructure in all four species. Rhodoplast digestive cell vacuoles either contained a whole rhodoplast or fragments of one or were empty. These results suggest that the inability to produce colored ink in some sea hare species is not due to either an absence of appropriate digestive machinery, that is, rhodoplast digestive cells, or an apparent failure of rhodoplast digestive cells to function. These results also propose that the digestive gland structure described herein occurred early in sea hare evolution, at least in the common ancestor to the generaAplysiaandDolabrifera. Our data, however, do not support the hypothesis that the loss of purple inking is a synapomorphy of the white-ink-producing subgenusAplysia.


Parasitology ◽  
2014 ◽  
Vol 142 (S1) ◽  
pp. S120-S127 ◽  
Author(s):  
GARETH D. WEEDALL ◽  
NEIL HALL

SUMMARYA key part of the life cycle of an organism is reproduction. For a number of important protist parasites that cause human and animal disease, their sexuality has been a topic of debate for many years. Traditionally, protists were considered to be primitive relatives of the ‘higher’ eukaryotes, which may have diverged prior to the evolution of sex and to reproduce by binary fission. More recent views of eukaryotic evolution suggest that sex, and meiosis, evolved early, possibly in the common ancestor of all eukaryotes. However, detecting sex in these parasites is not straightforward. Recent advances, particularly in genome sequencing technology, have allowed new insights into parasite reproduction. Here, we review the evidence on reproduction in parasitic protists. We discuss protist reproduction in the light of parasitic life cycles and routes of transmission among hosts.


Author(s):  
Irfan Ullah ◽  
Sridhar Kota

Abstract Use of mathematical optimization methods for synthesis of path-generating mechanisms has had only limited success due to the very complex nature of the commonly used Structural Error objective function. The complexity arises, in part, because the objective function represents not only the error in the shape of the coupler curve, but also the error in location, orientation and size of the curve. Furthermore, the common introduction of timing (or crank angle), done generally to facilitate selection of corresponding points on the curve for calculating structural error, has little practical value and unnecessarily limits possible solutions. This paper proposes a new objective function, based on Fourier Descriptors, which allows search for coupler curve of the desired shape without reference to location, orientation, or size. The proposed objective function compares overall shape properties of curves rather than making point-by-point comparison and therefore does not requires prescription of timing. Experimental evidence is provided to show that it is much easier to search the space of the proposed objective function compared to the structural error function.


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