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Phaseolus coccineus storage proteins. Extraction and characterization.
No full textPhaseolus coccineus storage globulins were extracted from mature cotyledons, purified and characterized. Three major proteins were separated. A component showing erythroagglutinating activity was thoroughly purified by thyroglobulin-Sepharose chromatography. The relative molecular masses of the three fractions are Mr = 330, 178, and 500 kDa as determined by polyacrylamide gel electrophoresis (PAGE). They correspond to the proteins found in other systems and classified as phytohaemagglutinin (PHA), vicilin and legumin, respectively. Electrophoretic analyses under denaturating conditions (SDS-PAGE) evidenced the major subunits for the three proteins. Isoelectrofocusing of the isolated proteins indicated a large heterogeneity for vicili
Characterization of Helianthus annuus storage proteins.
No full textA rapid method is described for isolating the globulin fraction (helianthinin) of sunflower seeds (Helianthus annum L.). The protein was characterized by chromatography and electrophoresis and compared with the globulin extracted from protein bodies. The native protein shows an apparent molecular weight of 300K, but, alternatively, a 190K band is present in some selfed lines of sunflower. Electrophoresis under denaturing conditions evidences four major components with molecular weights 39.2, 32.5, 25.6, and 23.2K, each containing two polypeptides and some minor polypeptides. In the 190K protein, the 32.9K component is absent. Isoelectric focusing indicated an heterogeneity of subunits within a pl range of 5.0-6.2 as confirmed by two-dimensional electrophoresis
INVITRO CULTURE OF BELLEVALIA-ROMANA (L) RCHB .3. CYTOLOGICAL STUDY OF SOMATIC EMBRYOS
No full textBellevalia romana (L.) Rchb., a monocotyledonous plant characterized by few (2n=2x=8) and very large chromosomes, may regenerate plants both via adventitious bud differentiation and via somatic embryogenesis in suspension cultures. Cytological analysis of numerous embryoids at different developmental stages in most of them revealed a mixoploid and aneusomatic condition which increased during embryo growth. Only globular proembryos were all entirely diploid. The results are discussed in relation to: i) the origin of the embryos; ii)de novo induction and increase in abnormal metaphases during embryogenesis; iii) embryo inability to develop into plant owing to chromosomal mosaicism
INVITRO CULTURE OF BELLEVALIA-ROMANA (L) RCHB .2. CYTOLOGICAL STUDY OF CALLUS AND REGENERATED PLANTLETS
No full textBellevalia romana (L.) Rchb., a monocotyledonous plant characterized by few (2 n=2 x=8) and very large chromosomes, is a useful subject for studying developmental problems in vitro. Cytological analysis of callus revealed that the majority of cells were diploid, but the remaining cells had aneuploid nuclei with a wide range of chromosome numbers, tetraploid and haploid nuclei. The frequency of aneuploid and polyploid cells was higher in callus grown in the presence of 2,4-D than in callus grown in NAA plus BAP. These nuclei seemed to increase with the duration of culture. The chromosome number distribution as determined by chromosome counts in calli at different culture times was confirmed by DNA cytophotometry. Chromosome number mosaicism (mixoploidy and aneusomaty) also occurred in all root apices of 9 out of 46 plantlets regenerated from callus via adventitious shoots
Phaseolus coccineus storage proteins. II. Electrophoretic analysis and erythroagglutinating activity in various cultivars.
No full textBiochemical analyses of seed storage proteins of Phaseolus coccineus have been carried out to identify seventeen different cultivars. The electrophoretic patterns in native polyacrylamide gel electrophoresis (PAGE) and denaturing conditions (SDS-PAGE); evidenced qualitative and quantitative differences for the three major protein components: legumin, vicilin and phytohaemagglutinin (PHA). The results were confirmed by isoelectrofocusing (IEF) analyses. Erythroagglutination tests showed the presence of high agglutinating activity particularly in cultivars with low vicilin content. The experimental results allow one to distinguish all the cultivars by their electrophoretic spectra and agglutinating activities
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
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