Meiotic irregularities in Alstroemeria andina var. Venustula (Alstroemeriaceae)

Alstroemeria andina Phil. var. venustula (Phil.) M. Muñoz (sub nom. A. andina Phil. subsp. venustula (Phil.) Ehr. Bayer) is a perennial, small herb, 5-16 cm tall, that occurs mainly at 2,800-3,700 meters above sea level, in populations of limited distribution from Argentina and Chile. The course of the meiosis was analyzed in a population of this taxon (2n = 2x = 16), and it proved to be highly irregular. It was characterized by presenting bridge and fragment configurations both at anaphases I and II. The highest number of bridges at anaphase I found in one cell was two, suggesting heterozygosity for as many as two paracentric inversions. Typical chiasmata were almost not detectable, even though they actually existed. The chiasma-like structures observed may be regarded as concealed chiasmata as it has been described in cryptochiasmate meiosis. A high frequency of tetrads with micronuclei was observed, implying significant levels of unbalanced gametes. Pollen stainability ranged between 28 and 30%. In Alstroemeria species the meiotic behaviour is highly regular, and the presence of rearrangements is very uncommon. The whole situation led us to suggest that some environmental factors have drastically affected the chromosome structure and the control of the meiotic process. The present study constitutes the first report of remarkable meiotic irregularities found in a wild population of this genus.Fil: Sanso, Andrea Mariel. Universidad Nacional del Centro de la Provincia de Buenos Aires; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Ecología, Genética y Evolución; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Wulff, Arturo Federico. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Ecología, Genética y Evolución; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Chromosome studies in Andean taxa of Alstroemeria (Alstroemeriaceae)

Meiotic or mitotic chromosomes of seven Alstroemeria taxa, native in Argentina and Chile and with Andean distribution were studied: A. andina ssp. uenustula, A. hookeri ssp. cummingiana, A. hookeri ssp. recumbens, A. pallida, A. patagonica, A. pseudospathulata and A. pygmaea. AlI were diploid with 2n = 16. Karyotypes of A. andina ssp.venustula and A. pygmaea were analysed, revealing similarity to previously analysed species. Thus, to all existing arguments for not retaining Schickendantzia as a separate genus, we can add another one which merges A. pygmaea with other Alstroemeria species, and does not support its taxonomic uniqueness. In general, the meiotic behaviour was normal, with regular formation of eight bivalents except in A. hookeri ssp. cummingiana, in one plant of which meiotic irregularities at various stages were observed. At the tetrad stage a large percentage of the cells presented micronuclei. The presence of 0-2 supernumerary chromosomes in A. hookeri ssp. recumbens is recorded. The karyotype asymmetry presented by most Alstroemeria species is discussed.Fil: Sanso, Andrea Mariel. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Botánica Darwinion. Academia Nacional de Ciencias Exactas, Físicas y Naturales. Instituto de Botánica Darwinion; Argentin

Heterogeneous sets: a diachronic typology of associative and similative plurals

This paper provides a diachronic typology of what we call ‘heterogeneous plurals’, an overarching term comprising associative plurals (expressions meaning X[person] & company) and similative plurals (expressions meaning X and similar entities). Based on a 110-language sample, we identify the most recurrent sources of these two types of plurals by means of various types of evidence (homophony/identity, internal reconstruction, comparison with cognate languages). The two types of plurals develop out of different source types: while the sources of associative plurals include elements that work as set constructors (plural anaphoric elements, plural possessives, names meaning ‘group’), those of similative plurals comprise elements with vague reference such as interrogative/indefinite items or uncertainty markers. There are also a few source types that may develop into both associative and similative plurals, such as connectives (‘and/with’) and universal quantifiers (‘every/all’). The differences in the diachronic pathways leading to the two types of plurals are explained in terms of the different referential properties of the nominal bases from which they are formed (proper names/kin terms vs. common nouns), but also taking into account the typical discourse contexts in which the two types of plurals are employed

Chromosomes of some argentine angiosperms and their taxonomic significance

Meiotic or mitotic chromosomes of eleven species of angiosperms native in Argentina, belonging to seven families, were studied in order to be used in cytotaxonomic studies and gain some insights on the evolutive relationships of the different groups. Most of our data were the first cytological information for the species. The genus Alvaradoa Liebm. was investigated cytologically for the first time. The novel karyologically studied species, all diploid, were: Bomarea macrocephala Pax and Bomarea stans Kränz. 2n = 18, Loasa bergii Hieron. 2n = 26, Alvaradoa subovata Cronquist 2n = 16, Schizanthus grahamii Gillies 2n = 20, Viola montagnei Gay and Viola roigii Rossow 2n = 14. The same numbers to the ones previously reported in the literature were found from different populations of Cajophora chuquitensis (Meyen) Urb. & Gilg. 2n = 18, Ramorinoa girolae Speg. 2n = 20, and Schizanthus grahamii Gillies 2n = 20. The presence of supernumerary chromosomes, 0 to 6, in Ligaria cuneifolia (Ruiz & Pav.) Tiegh., 2n = 20, was recorded. Data are compared with previously published results and chromosome figures of all studied species are provided.Fil: Sanso, Andrea Mariel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tandil. Centro de Investigación Veterinaria de Tandil. Universidad Nacional del Centro de la Provincia de Buenos Aires. Centro de Investigación Veterinaria de Tandil. Provincia de Buenos Aires. Gobernación. Comision de Investigaciones Científicas. Centro de Investigación Veterinaria de Tandil; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Ecología, Genética y Evolución; ArgentinaFil: Seo, Micaela Noemi. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Botánica Darwinion. Academia Nacional de Ciencias Exactas, Físicas y Naturales. Instituto de Botánica Darwinion; Argentin

Chromosomal studies in species of Salvia (Lamiaceae) from Argentina

Meiotic and mitotic chromosomes of 13 species of Salvia from Argentina were studied. Most of our data are new counts but some, mainly from cultivated species, confirm previous reports or represent numbers which are different from those cited previously. Only Salvia gilliesii Benth. and the introduced species S. coccinea Juss., S. farinacea Benth., S. involucrata Cavo and S. microphylla Kunth are diploids. S. cardiophylla Benth., S. procurrens Benth., S. splendens Roem. & Schult. and S. uliginosa Benth. are tetraploids; S. stachydifolia Benth. is hexaploid; and S. guaranitica A. St.-Hil., S. pallida Benth. and S. rypara Briq. are octoploids. The basic number most frequentIy found is x = 11, but two species, S. procurrens and S. uliginosa, have x = 13. S. farinacea has x = 10 but this species is a widespread cultivated plant, not native in this area. Seven of the studied species showed one to three B chromosomes. We discuss some systematic and evolutionary aspects of the genus in the light of the cytogenetic data, the relationships between geographical distribution and chromosome numbers in relation to levels of ploidy and basic chromosome numbers, and make comparisons with some of the different taxonomic sections.Fil: Alberto, Cecilia. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Laboratorio de Etnobotánica y Botánica Aplicada; ArgentinaFil: Sanso, Andrea Mariel. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Botánica Darwinion. Academia Nacional de Ciencias Exactas, Físicas y Naturales. Instituto de Botánica Darwinion; ArgentinaFil: Xifreda, Cecilia Carmen. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Laboratorio de Etnobotánica y Botánica Aplicada; Argentin

Foliar anatomy and micromorphology of southern South American Alstroemeriaceae: Alstroemerieae, and its systematic implications in Alstroemeria

Alstroemerieae is an exclusively Central and South American tribe belonging to Alstroemeriaceae, which comprises two large genera, Alstroemeria and Bomarea. Alstroemeria has two areas of distribution, mediterranean Chile and central southeastern Brazil. Most Bomarea species grow in forests and hedges in moist areas, however, some species are adapted to dry Andean valleys and high altitudes. Previous leaf anatomical data were obtained from a limited group of species. To assess the value of the anatomical characters for the systematics and their importance as adaptations to different environments, we compared representative species from different geographical areas and habitats. Data regarding leaf anatomy and micromorphology were obtained from light microscopy and scanning electron microscopy and were combined with macromorphology for 27 Alstroemerieae species. In accordance with earlier studies, our results show variation in relation to several leaf morpho-anatomical characters. Based on these we define seven types. We furthermore analyzed the morpho-anatomical characters in a phylogenetic context. Morpho-anatomical characters are highly homoplastic within the family. Leaf anatomy may support monophyly of Baker's informal grouping of Alstroemeria Brazilian species with rigid leaves, however, a more thorough study of Brazilian Alstroemeria species are needed to confirm this.Laboratorio de Etnobotánica y Botánica Aplicad

Chromosomal studies in species of Salvia (Lamiaceae) from Argentina

Meiotic and mitotic chromosomes of 13 species of Salvia from Argentina were studied. Most of our data are new counts but some, mainly from cultivated species, confirm previous reports or represent numbers which are different from those cited previously. Only Salvia gilliesii Benth. and the introduced species S. coccinea Juss., S. farinacea Benth., S. involucrata Cav. and S. microphylla Kunth are diploids. S. cardiophylla Benth., S. procurrens Benth., S. splendens Roem. & Schult. and S. uliginosa Benth. are tetraploids; S. stachydifolia Benth. is hexaploid; and S. guaranitica A. St.-Hil., S. pallida Benth. and S. rypara Briq. are octoploids. The basic number most frequently found is x = 11, but two species, S. procurrens and S. uliginosa, have x = 13. S. farinacea has x = 10 but this species is a widespread cultivated plant, not native in this area. Seven of the studied species showed one to three B chromosomes. We discuss some systematic and evolutionary aspects of the genus in the light of the cytogenetic data, the relationships between geographical distribution and chromosome numbers in relation to levels of ploidy and basic chromosome numbers, and make comparisons with some of the different taxonomic sections.Facultad de Ciencias Naturales y Muse

Cryptanalysis of an oblivious PRF from supersingular isogenies

We cryptanalyse the SIDH-based oblivious pseudorandom function from supersingular isogenies proposed at Asiacrypt’20 by Boneh, Kogan and Woo. To this end, we give an attack on an assumption, the auxiliary one-more assumption, that was introduced by Boneh et al. and we show that this leads to an attack on the oblivious PRF itself. The attack breaks the pseudorandomness as it allows adversaries to evaluate the OPRF without further interactions with the server after some initial OPRF evaluations and some offline computations. More specifically, we first propose a polynomial-time attack. Then, we argue it is easy to change the OPRF protocol to include some countermeasures, and present a second subexponential attack that succeeds in the presence of said countermeasures. Both attacks break the security parameters suggested by Boneh et al. Furthermore, we provide a proof of concept implementation as well as some timings of our attack. Finally, we examine the generation of one of the OPRF parameters and argue that a trusted third party is needed to guarantee provable security.SCOPUS: cp.kinfo:eu-repo/semantics/publishe

Pathogenicity Islands Distribution in Non-O157 Shiga Toxin-Producing Escherichia coli (STEC)

Shiga toxin-producing Escherichia coli (STEC) are foodborne pathogens associated with outbreaks and hemolytic-uremic syndrome. Cattle and meat foods are the main reservoir and infection source, respectively. Pathogenicity islands (PAIs) play an important role in STEC pathogenicity, and non-locus of the enterocyte effacement(LEE) effector (nle) genes present on them encode translocated substrates of the type III secretion system. A molecular risk assessment based on the evaluation of the nle content has been used to predict which STEC strains pose a risk to humans. The goal was to investigate the distribution of the PAIs OI (O-island)-36 (nleB2, nleC, nleH1-1, nleD), OI-57 (nleG2-3, nleG5-2, nleG6-2), OI-71 (nleA, nleF, nleG, nleG2-1, nleG9, nleH1-2) and OI-122 (ent/espL2, nleB, nleE, Z4321, Z4326, Z4332, Z4333) among 204 clinical, food and animal isolates belonging to 52 non-O157:H7 serotypes. Differences in the frequencies of genetic markers and a wide spectrum of PAI virulence profiles were found. In most LEE-negative strains, only module 1 (Z4321) of OI-122 was present. However, some unusual eae-negative strains were detected, which carried other PAI genes. The cluster analysis, excluding isolates that presented no genes, defined two major groups: eae-negative (determined as seropathotypes (SPTs) D, E or without determination, isolated from cattle or food) and eae-positive (mostly identified as SPTs B, C, or not determined).Fil: Cadona, Jimena Soledad. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tandil. Centro de Investigación Veterinaria de Tandil. Universidad Nacional del Centro de la Provincia de Buenos Aires. Centro de Investigación Veterinaria de Tandil. Provincia de Buenos Aires. Gobernación. Comision de Investigaciones Científicas. Centro de Investigación Veterinaria de Tandil; ArgentinaFil: Bustamante, Ana Victoria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tandil. Centro de Investigación Veterinaria de Tandil. Universidad Nacional del Centro de la Provincia de Buenos Aires. Centro de Investigación Veterinaria de Tandil. Provincia de Buenos Aires. Gobernación. Comision de Investigaciones Científicas. Centro de Investigación Veterinaria de Tandil; ArgentinaFil: González, Juliana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tandil. Centro de Investigación Veterinaria de Tandil. Universidad Nacional del Centro de la Provincia de Buenos Aires. Centro de Investigación Veterinaria de Tandil. Provincia de Buenos Aires. Gobernación. Comision de Investigaciones Científicas. Centro de Investigación Veterinaria de Tandil; ArgentinaFil: Sanso, Andrea Mariel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tandil. Centro de Investigación Veterinaria de Tandil. Universidad Nacional del Centro de la Provincia de Buenos Aires. Centro de Investigación Veterinaria de Tandil. Provincia de Buenos Aires. Gobernación. Comision de Investigaciones Científicas. Centro de Investigación Veterinaria de Tandil; Argentin

Additions and precisions on the pollen morphology of Alvaradoa subovata (Simaroubaceae) and Roupala brasiliensis (Proteaceae)

Morphological observations on pollen grains of Alvaradoa subovata Cronquist (Simaroubaceae) and Roupala brasiliensis Klotzch (Proteaceae) obtained from TEM complement previous studies of Xifreda & Sanso (1998). With the aim of giving details of the morphology and accuracy to the descriptive terminology, exine stratification is described and new observations on pollen grains obtained from SEM are added.Se dan a conocer observaciones con microscopio electrónico de transmisión (MET), que complementan los estudios previos realizados con microscopio electrónico de barrido (MEB) sobre la morfología polínica de Alvaradoa subovata Cronquist (Simaroubaceae) y Roupala brasiliensis Klotzch (Proteaceae) (Xifreda & Sanso, 1998). Se describe la estratificación de la exina y se comunican nuevas observaciones con MEB sobre el polen de estas dos especies arbóreas, con la finalidad de aclarar su morfología y dar precisión a la terminología descriptiva utilizada en Xifreda & Sanso (1998).Facultad de Ciencias Naturales y Muse