Digenomic triploids for an assessment of chromosome relationships in the cultivated diploid Brassica species

Genome ◽  
1987 ◽  
Vol 29 (2) ◽  
pp. 326-330 ◽  
Author(s):  
T. Attia ◽  
C. Busso ◽  
G. Röbbelen

To assess the chromosomal relationships in the cultivated diploid Brassica species, four digenomic triploid combinations were synthesized and meiotically analyzed. Two of the four digenomic combinations contained the B genome of B. nigra, one with two (BC.B) and the other with only one B genome (C.BC). In these combinations preferential pairing between the two homologous genomes with the third single genome was predominant. Since gene actions suppressing pairing between chromosomes of related genomes had not been proven to exist in Brassica, this phenomenon is assumed to be conditioned by structural chromosomal differences reflecting the distant phylogenetic relationship of B. nigra to each of B. oleracea (CC) and B. campestris (AA). On the other hand, two other digenomic triploids having two A genomes and one C genome showed a low preferential pairing of the two homologous A genomes (to form 10 II + 9 I). Moreover, a high tendency for an allosyndetic pairing between the A and C genomes was expressed by the formation of one or more trivalents in over 50% of PMCs in the two combinations A.AC and AC.A. This demonstrated a high meiotic pairing potential and a small evolutionary difference between the chromosomes of B. campestris (AA) and B. oleracea (CC). Key words: Brassica, triploid (digenomic), phylogenetics, pairing (chromosome).

Genome ◽  
1989 ◽  
Vol 32 (2) ◽  
pp. 169-172 ◽  
Author(s):  
J. Orellana ◽  
J. F. Vazquez ◽  
J. M. Carrillo

Using C-banding, homologous and homoeologous meiotic pairing between wheat (AB), rye (R), and Aegilops caudata (C) genomes were estimated at meiotic metaphase I in trigeneric hybrids (AABBRC; 2n = 6x = 42). In all hybrids, the C-genome chromosomes pair homoeologously only with chromosomes of the A genome, but not with chromosomes of the B genome or R genome. The A – C pairing was restricted to trivalents (0.15 per cell), each composed of two A-genome and one C-genome chromosomes. These preliminary data suggest that the C genome of Ae. caudata is probably more closely related to the A genome than to the B genome of wheat.Key words: trigeneric hybrid, wheat, rye, Aegilops, genome analysis, meiosis.


During the last few years of his life Prof. Simon Newcomb was keenly interested in the problem of periodicities, and devised a new method for their investigation. This method is explained, and to some extent applied, in a paper entitled "A Search for Fluctuations in the Sun's Thermal Radiation through their Influence on Terrestrial Temperature." The importance of the question justifies a critical examination of the relationship of the older methods to that of Newcomb, and though I do not agree with his contention that his process gives us more than can be obtained from Fourier's analysis, it has the advantage of great simplicity in its numerical work, and should prove useful in a certain, though I am afraid, very limited field. Let f ( t ) represent a function of a variable which we may take to be the time, and let the average value of the function be zero. Newcomb examines the sum of the series f ( t 1 ) f ( t 1 + τ) + f ( t 2 ) f ( t 2 + τ) + f ( t 3 ) f ( t 3 + τ) + ..., where t 1 , t 2 , etc., are definite values of the variable which are taken to lie at equal distances from each other. If the function be periodic so as to repeat itself after an interval τ, the products are all squares and each term is positive. If, on the other hand, the periodic time be 2τ, each product will be negative and the sum itself therefore negative. It is easy to see that if τ be varied continuously the sum of the series passes through maxima and minima, and the maxima will indicated the periodic time, or any of its multiples.


Genome ◽  
1992 ◽  
Vol 35 (1) ◽  
pp. 140-146 ◽  
Author(s):  
R. J. Singh ◽  
K. P. Kollipara ◽  
F. Ahmad ◽  
T. Hymowitz

The objective of this study was to discover the diploid progenitors of 80-chromosome Glycine tabacina with adventitious roots (WAR) and no adventitious roots (NAR). Three synthetic amphiploids were obtained by somatic chromosome doubling. These were (i) (G. latifolia, 2n = 40, genome B1B1,) × (G. microphylla, 2n = 40, genome BB) = F1(2n = 40, genome BB1) – 0.1% colchicine treatment (CT) – 2n = 80, genome BBB1B1; (ii) (G. canescens, 2n = 40, genome AA) × G. microphylla, 2n = 40, genome BB) = F1 (2n = 40, genome AB) – (CT) – 2n = 80, genome AABB; (iii) (G. latifolia, 2n = 40, B1B1) × G. canescens, 2n = 40, AA) = F1 (2n = 40, genome AB1) – (CT) – 2n = 80, genome AAB1B1. The segmental allotetraploid BBB1B1 was morphologically similar to the 80-chromosome G. tabacina (WAR), but meiotic pairing data in F1 hybrids did not support the complete genomic affinity. Despite normal diploid-like meiosis in allotetraploids AABB and AAB1B1, AABB was completely fertile, while pod set in AAB1B1 was very sparse. Morphologically, allotetraploid AABB was indistinguishable from the 80-chromosome G. tabacina (NAR) but in their F1 hybrids, the range of univalents at metaphase I was wide (4–44). The allotetraploid AAB1B1 did not morphologically resemble the 80-chromosome G. tabacina (NAR). However, the F1 hybrid of AABB × AAB1B1 showed normal meiosis with an average chromosome association (range) of 1.7 I (0–4) + 39.2 II (38–40). Based on this information, we cannot correctly deduce the diploid progenitor species of the 80-chromosome G. tabacina (NAR). The lack of exact genome homology may be attributed to the geographical isolation, natural mutation, and growing environmental conditions since the inception of 80-chromosome G. tabacina. Thus, it is logical to suggest that the 80-chromosome G. tabacina (NAR) is a complex, probably synthesized from A genome (G. canescens, G. clandestina, G. argyrea, G. tomentella D4 isozyme group) and B genome (G. latifolia, G. microphylla, G. tabacina) species, and the 80-chromosome G. tabacina (WAR) complex was evolved through segmental allopolyploidy from the B genome species.Key words: Glycine spp., allopolyploidy, colchicine, genome, intra- and inter-specific hybridization, polyploid complex.


1944 ◽  
Vol 90 (380) ◽  
pp. 753-760 ◽  
Author(s):  
E. Stengel

In recent years important additions to the knowledge of the symptomatology in cases with involvement of the parietal lobe have been made. Both constructional apraxia (Kleist, 1922) and Gerstmann's syndrome, consisting of finger-agnosia, disturbance of right-left orientation, agraphia and acalculia (1924) have been related to lesions of the angular gyrus of the dominant hemisphere. Before the description of those symptoms, a loss of spatial orientation had been described in cases with lesions of the same localization. Balint (1910), Riddoch (1917), and others had observed that symptom in single cases, but the most comprehensive description was given by Gordon Holmes (1918), who studied it in a case-material of war injuries. When Holmes and his co-workers published their observations, constructional apraxia and Gerstmann's syndrome were still unknown. Loss of spatial orientation as a fully developed symptom is rare, while the other two disorders are not uncommon. For this reason the psychopathological relationship of those symptoms is still insufficiently understood. The following case offers an opportunity for studying the problem:


1990 ◽  
Vol 7 (4) ◽  
pp. 329-346 ◽  
Author(s):  
William McTeer ◽  
James E. Curtis

This study examines the relationship between physical activity in sport and feelings of well-being, testing alternative interpretations of the relationship between these two variables. It was expected that there would be positive relationships between physical activity on the one hand and physical fitness, feelings of well-being, social interaction in the sport and exercise environment, and socioeconomic status on the other hand. It was also expected that physical fitness, social interaction, and socioeconomic status would be positively related to psychological well-being. Further, it was expected that any positive zero-order relationship of physical activity and well-being would be at least in part a result of the conjoint effects of the other variables. The analyses were conducted separately for the male and female subsamples of a large survey study of Canadian adults. The results, after controls, show a modest positive relationship of physical activity and well-being for males but no such relationship for females. The predicted independent effects of the control factors obtained for both males and females. Interpretations of the results are discussed.


2015 ◽  
Vol 1120-1121 ◽  
pp. 1109-1114
Author(s):  
Xin Lei ◽  
Hui Huang ◽  
S.P. Wen

This study investigated the mechanical properties and microstructures of Er-containing Al–Mg alloys. The research found that the H114-T sheet of Er-containing Al–Mg alloys showed a relative good comprehensive performance in mechanical properties. With the special rolling and heat treatment process, this H114-T sheet showed different morphology of microstructures with the other sheets in Er-containing Al–Mg alloys. Grains in H114-T sheet performed irregular shape polygon, a number of subgrains appeared in grains, the amount of dislocations in grains decreased. H114-T sheet possessed a lot of Copper texture, this may be one of important factors influenced the mechanical properties.


1956 ◽  
Vol 23 (1) ◽  
pp. 120-125 ◽  
Author(s):  
J. Czulak ◽  
Jill Naylor

A lysogenic culture, prepared in the laboratory from a strain of Streptococcus lactis, was used as a cheese starter in commercial factories. It was attacked in turn by two other unrelated phage races. The lysogenic condition, which involved slight morphological and physiological changes, persisted in the subsequent forms resistant to one or both the new phage races. Acquired resistance to any one of the three phages did not protect the culture from the other two phages.In nature such interactions between phage races and lactic acid bacteria must be constantly taking place, giving rise to similarly related strains.Two of the three phage races produced spreading haloes around their plaques due to a lysin released during phage action. The lysin may also interfere with the survival of secondary growth after attack by these phage races. Production of this type of lysin is thus a property of the phage race and not of the bacterial strain.


PEDIATRICS ◽  
1962 ◽  
Vol 30 (6) ◽  
pp. 909-916
Author(s):  
Herbert I. Goldman ◽  
Samuel Karelitz ◽  
Hedda Acs ◽  
Eli Seifter

One hundred four healthy premature infants, of birth weight 1,000 to 1,800 gm, were fed one of five feedings: (1) human milk; (2) human milk plus 13 meq/l of sodium chloride; (3) human milk plus 13 meq/l of sodium chloride and 18 meq/l of potassium chloride; (4) a half-skimmed cows milk formula; and (5) a partially-skimmed vegetable oil, cows milk formula. The infants fed any of the three human milk formulas gained weight at a slower rate than the infants fed either of the two cows milk formulas. Infants whose diets were changed from unmodified human milk to the half-skimmed cows milk gained large amounts of weight, and at times were visibly edematous. Infants whose diets were changed from the human milks with added sodium chloride, to the half-skimmed cows milk, gained lesser amounts of weight and did not become edematous. The infants fed the two cows milk diets gained similar amounts of weight, although one diet provided 6.5 gm/kg/day, the other 3.1 gm/kg/day of protein.


Lampas ◽  
2019 ◽  
Vol 52 (4) ◽  
pp. 437-452
Author(s):  
Gerard Boter

Summary The present article discusses three hotly debated interpretational issues in Diotima´s speech in Plato´s Symposium. The first of these is the relationship of Diotima´s speech to other dialogues, such as the Phaedo and the Republic, with regard to the immortality of the soul. It is argued that there is no discrepancy at all, because the immortality of the soul does not play any role in the Symposium. The second issue is the nature of the three classes of posterity: biological, spiritual and philosophical. Whereas the posterity of the first two classes can be relatively easily defined, the character of the philosopher´s posterity, ‘true virtue’, remains rather vague. It may consist in dialectical teaching of the Idea of Beauty by Socrates. Thirdly, it is argued that the philosopher´s immortality differs only gradually from the immortality of the other two classes, that is, the philosopher as a man only survives by means of his posterity.


2021 ◽  
pp. 252-268
Author(s):  
V. V. Dyachkov ◽  

The paper deals with the grammaticalization problems in Tomo Kan (Dogon family, Niger-Congo) and, in particular, with the diachronic relationship of polypredicative constructions and TAM markers. Dogon languages are characterized by TAM systems that seem to be dia-chronically unstable since markers with a similar range of meanings go back to different lexi-cal sources in different languages of the family. TAM markers are apparently associated with polypredicative constructions, which are very common in Dogon and preserve some of their morphosyntactic properties. At the same time, Dogon languages are characterized by complex tonal changes triggered not only by phonological context but also by the syntactic position of constituents. These tonal changes, frequently referred to as tonosyntax, accompany the formation of polypredicative constructions and other syntactic phenomena. A thorough inves-tigation of Tomo Kan TAM markers shows their tonosyntactic properties to resemble those of polypredicative constructions. Moreover, assuming that tonosyntax of polypredicative con-structions triggers certain tonal contour overlays, one can account for tonal alternations ob-served in TAM forms which would have been left otherwise unexplained. However, the anal-ysis also reveals that at least two classes of TAM forms must be distinguished in Tomo Kan: one of them inherits the tonosyntax of polypredicative constructions while the other does not. A hypothesis is put forward that the latter class has a different source of grammaticalization and is probably associated with verb stem incorporation rather than with polypredication. Methodologically, the paper shows a critical role of tonology in the analysis of grammaticalization processes in tonal languages.


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