The Relationship between 2C DNA Content, Life Cycle Type, Systematic Position, and the Level of DNA Endoreplication in Nuclei of Parenchyma Cells during Growth and Differentiation of Roots in some Monocotyledonous Species

1982 ◽  
Vol 177 (4-5) ◽  
pp. 319-336 ◽  
Author(s):  
Maria J. Olszewska ◽  
Regina Osiecka
2014 ◽  
Vol 62 (3-4) ◽  
pp. 143-147
Author(s):  
Kazimierz Marciniak

The DNA content after the Feulgen reaction in the endosperm of three monocotyledonous plant species (<i>Asparagus officinalis</i>, <i>Muscari comosom</i>, <i>Haemanthus kurharinae</i>) differing in their 2C DNA content, was cytophotometrically measured. During endosperm development 1-6 endoreplication cycles take place, depending on the species. Differences in nuclear DNA endoreplication dynamics in the tested species are similar to those occurring in root parenchyma, but the endoreplication level in the endosperm is higher.


Genes ◽  
2021 ◽  
Vol 12 (4) ◽  
pp. 563
Author(s):  
Monika Rewers ◽  
Iwona Jedrzejczyk ◽  
Agnieszka Rewicz ◽  
Anna Jakubska-Busse

Orchidaceae is one of the largest and the most widespread plant families with many species threatened with extinction. However, only about 1.5% of orchids’ genome sizes have been known so far. The aim of this study was to estimate the genome size of 15 species and one infraspecific taxon of endangered and protected orchids growing wild in Poland to assess their variability and develop additional criterion useful in orchid species identification and characterization. Flow cytometric genome size estimation revealed that investigated orchid species possessed intermediate, large, and very large genomes. The smallest 2C DNA content possessed Liparis loeselii (14.15 pg), while the largest Cypripedium calceolus (82.10 pg). It was confirmed that the genome size is characteristic to the subfamily. Additionally, for four species Epipactis albensis, Ophrys insectifera, Orchis mascula, Orchis militaris and one infraspecific taxon, Epipactis purpurata f. chlorophylla the 2C DNA content has been estimated for the first time. Genome size estimation by flow cytometry proved to be a useful auxiliary method for quick orchid species identification and characterization.


2015 ◽  
Vol 808 ◽  
pp. 359-363
Author(s):  
Cristina Feniser ◽  
Florin Lungu

So far little attention has been given the differences or the compatibilities between CSR and innovation. Few works treats CSR in combination with innovation. What exactly is the relationship between CSR and innovation? Recent phenomena such as open innovation is based on the concept that the stakeholder's dialogue that overlaps with some dimensions of CSR. Being innovative means to bring organizational and technical improvements which will translate into a better position in the market. These improvements don't just aim the product, but the process by which it is obtained and its whole life-cycle. We're talking about a new approach to innovation, namely its orientation towards sustainability. Although SMEs have many features which facilitate implementation of CSR, activities of this type in such organizations are still limited. SMEs managers often make choices that are related to rational management. This leads to divergence between economical and social goals. Through a qualitative exploration of the concepts of CSR and innovation, we wanted to find out from some managers whether there is a link between innovation and CSR in SMEs and whether the activities corresponding to the two concepts overlap in a certain measure.


2020 ◽  
Vol 29 (3) ◽  
pp. 797-826
Author(s):  
Guoqian Xi ◽  
Jörn Block ◽  
Frank Lasch ◽  
Frank Robert ◽  
Roy Thurik

Abstract Business takeovers and new venture start-ups are two important and distinct entry modes of entrepreneurship. They differ from resource-based and organizational ecology perspectives. We compare firm survival patterns and determinants associated with the two entry modes. From two large French datasets, we find that business takeovers have a higher survival rate than new venture start-ups. However, these differences in survival probability reduce over the entrepreneurship life cycle and when controlling for different entrepreneur and firm characteristics. Moreover, we identify differences in determinants of survival for the two groups, highlighting a distinction between the two entrepreneurship entry modes. This work contributes to the literature on the relationship between entrepreneurship entry and firm survival, thereby contributing to both entrepreneurship and firm survival research.


2014 ◽  
Vol 64 (4) ◽  
pp. 333-342 ◽  
Author(s):  
Marcos de Miranda Leão Leite ◽  
Cynthia Yuri Ogawa ◽  
Carla Ferreira Rezende ◽  
José Roberto Feitosa Silva

The relationship between weight and size of individuals can be used to evaluate the status of a population, which is particularly useful for natural populations that are being exploited. Ucides cordatus occurs on the Atlantic coast of the American continent, from Florida (USA) to Santa Catarina (Brazil). This species is economically very important, most of all in the Northeastern area of Brazil, as well as in the Dominican Republic and Suriname. The objective of this study was to analyze life phases (‘fattening’, ‘matumba’, ‘milk-crab’, ‘maturation’ and ‘walking’) by use of the weight-length relationships, as well as temporal variations in this condition factor for each sex of U. cordatus. For this purpose, individuals were sampled monthly for twenty-four months at the Jaguaribe River estuary, Ceará State, Northeastern Brazil. The relationship between total weight and cephalothorax width was established using regression analysis, adjusted by a power equation. The dynamics of the condition factor were analyzed for each sex using the variation of its averages related to annual life cycle; this was done for each of the previously-mentioned phases. The relationship between total weight and cephalothorax width showed an isometric growth in males and negative allometric growth in females suggesting that, for the same reference size, males are heavier than females. When considering the average of the female condition factors, these were greater than those for males during the annual life cycle, except during the ‘maturation’ phase, which is the phase with a higher demand of energetic reserves for males. Annual variation of the condition factor in females presented no significant difference.


Author(s):  
LeRoy E. Taylor ◽  
Mark R. Henderson

Abstract This paper describes the roles of features and abstraction mechanisms in the mechanical design process, mechanical designs, and product models of mechanical designs. It also describes the relationship between functions and features in mechanical design. It is our experience that many research efforts exist in the areas of design and product modeling and, further, that these efforts must be cataloged and compared. To this end, this paper culminates with the presentation of a multi-dimensional abstraction space which provides a unique framework for (a) comparing mechanical engineering design research efforts, (b) relating conceptual objects used in the life cycle of mechanical products, and (c) defining a product modeling space.


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