Secondary origin, hybridization and sexual reproduction in a diploid-tetraploid contact zone of the facultatively apomictic orchid Zygopetalum mackayi.

The production of triploids and apomictic reproduction are important processes for polyploid establishment and cytotype coexistence, but we know little about the interaction between triploids and facultatively apomictic plants. To bridge this gap, we studied the pollen-dependent, facultatively apomictic orchid Zygopetalum mackayi from high-elevation outcrops of southeast Brazil. We described the nature of the contact between Z. mackayi cytotypes and patterns of genetic diversity and structure based on eight microsatellite markers and 155 individuals of pure tetraploid, pure diploid and mixed cytotype populations. Our results revealed high values of genetic and genotypic diversity within all populations of Z. mackayi. Each cytotype emerged as a genetic distinct cluster, combining individuals from different populations. Triploids clustered in an intermediate position between diploids and tetraploids. Most genetic variance is associated with individuals within populations and genetic differentiation is high among populations. Mixed cytotype populations of Z. mackayi originate from secondary contact. Triploids are hybrids between diploids and tetraploids and likely act as a bridge. Our results point to the predominance of sexual reproduction in all populations but do not corroborate previous basic chromosome number for this species. Polyploidy rather than facultative apomixis may explain the larger geographic distribution of tetraploids of Z. mackayi.

Frailty Could Predict Death in Older Adults after Admissionat Emergency Department? A 6-month Prospective Study from a Middle-Income Country.

BACKGROUND: The number of older adults attending emergency department (ED) is increasing all over the world. Usually, those patients are potentially more complex due to their greater number of comorbidities, cognitive disorders, and functional or physical disabilities. Frailty is a vulnerable state that could predict adverse outcomes of those patients. There are very few studies that addressed this topic in the ED, and none of them used a simple instrument for frailty assessment. OBJECTIVES: The primary outcome was to evaluate the association between frailty identified through the FRAIL questionnaire at baseline and death after a 6-month follow-up period after hospital discharge from the ED. Secondary outcomes were readmission to the ED and disability after 6 months. METHODS: A 6-month follow-up prospective study (FASES study) was conducted at a university-based trauma-center ED in Jundiaí, southwestern of Brazil. A total of 316 older adults aged 60 or older were randomly included based on a lottery of their medical record admission number. Frailty was evaluated through the FRAIL questionnaire. The association between frailty and death was estimated through a binary logistic regression adjusted for age, sex, and cognitive performance. RESULTS: From the total sample, the mean age was 72.11±8.0 years, and 51.6% were women. Participants presented 2.28±1.4 comorbidities and 25.6% were frail. Mean hospital stay was 5.43±5.6 days. Death occurred in 52 participants, readmission to the emergency in 55, and new disability in 16 after 6 months. Frailty was associated with an odds ratio of 2.18 for death after 6 months (95% CI = 1.10-4.31; p = 0.024). This association lost significance after multivariate analysis taking into account cognitive performance. There was no association between frailty status at baseline and readmission to the ED or disability. CONCLUSION: The identification of frailty using the FRAIL at admission was not predictive of death after a 6-month period after discharge from the ED. Simple frailty assessment could identify patients at higher risk for death in the follow-up.

Pan-American Similarities in Genetic Structures of Helicoverpa armigera and Helicoverpa zea (Lepidoptera: Noctuidae) With Implications for Hybridization.

The genus Helicoverpa (Lepidoptera: Noctuidae) includes phytophagous and polyphagous agricultural insect pests. In the Americas, a native pest, Helicoverpa zea (Boddie), and an invasive pest, Helicoverpa armigera (Hübner), are causing severe damage in vegetable and agronomic crops. The population structure of both species in South America is poorly understood, and the phylogenetic relatedness of H. armigera and H. zea suggests natural interspecific gene flow between these species. Using microsatellite loci, we investigated: 1) the genetic diversity and gene flow of H. armigera specimens from Brazil; 2) the genetic diversity and gene flow between H. zea specimens from Brazil and the United States; and 3) the possibility of interspecific gene flow and the frequency of putative hybrids in Brazil. We detected high intraspecific gene flow among populations collected in the same country. However, there is a geographic limit to gene flow among H. zea individuals from South and North America. Pairwise Fst and private alleles showed that H. armigera is more similar to H. zea from Brazil than H. zea from the United States. A comparative STRUCTURE analysis suggests natural hybridization between H. armigera and H. zea in Brazil. High gene flow and natural hybridization are key traits to population adaptation in new and disturbed environments, which can influence the management of these pests in the American continent.

Genetic diversity of Casearia sylvestris populations in remnants of the Atlantic Forest.

Guaçatonga (Casearia sylvestris) is a native plant of the Atlantic Forest, with high medicinal potential and relevance for reforestation programs. The aim of this study was to characterize, with microsatellite markers, two populations of C. sylvestris from remaining areas of the Atlantic Forest in the State of São Paulo. High allelic variation was found in both populations (NA = 101 and 117; AR = 12.5 and 14.4), although with high endogamy coefficients (f = 0.640 and 0.363). Estimates of genetic structure suggested the presence of considerable genetic divergence between the populations (FST = 0.103); however, there was no spatial genetic structure within the populations. Genetic divergence may have occurred due to decreased gene flow between the fragmented populations as the result of deforestation. The results of this study demonstrate the importance of genetic diversity and its characterization in native plants within remaining forest areas for the management and restoration of such areas.

Cross-species amplification and polymorphism of microsatellite loci in Helicoverpa armigera and Helicoverpa zea (Lepidoptera: Noctuidae) in Brazilian cropping systems.

The Old World bollworm Helicoverpa armigera (Hübner) was recently discovered in Brazil. This species is closely related to the New World bollworm H. zea (Boddie), and mating between these species has already been reported under laboratory conditions. Here, we tested the cross-species amplification of 20 microsatellite (SSR) loci in field populations of H. armigera and H. zea collected from Brazilian cropping systems. Seven SSR loci were successfully amplified and polymorphic in both species except for the locus HaC14, which was monomorphic for H. zea. All SSR loci were in linkage equilibrium, and deviations from Hardy- Weinberg equilibrium were only observed for the locus HarSSR1 in the HaRS-2 population, where null alleles were present. A moderate level of polymorphism was detected in H. armigera and H. zea populations with a mean allele number of 4.14, and 2.24, respectively. Interestingly, most of the populations of the recent invader H. armigera showed higher genetic diversity and inbreeding coefficients than H. zea populations. The genetic identity of each species was recovered using a STRUCTURE analysis, where the populations formed two clusters (K = 2) according to their species. STRUCTURE also suggested the occurrence of potential hybrid offspring between H. armigera and H. zea individuals in natural conditions. These SSR loci will be valuable in characterizing population differentiation, invasion routes, adaptation, reproductive behavior, and intra- and interspecific gene flow in H. armigera and H. zea populations in Brazil, the USA, and other areas where these two pests occur.

Photonic superdiffusive motion in resonance line radiation trapping Partial frequency redistribution effects.

The relation between the jump length probability distribution function and the spectral line profile in resonance atomic radiation trapping is considered for partial frequency redistribution (PFR) between absorbed and reemitted radiation. The single line opacity distribution function [M. N. Berberan-Santos et al., J. Chem. Phys. 125, 174308 (2006)] is generalized for PFR and used to discuss several possible redistribution mechanisms (pure Doppler broadening; combined natural and Doppler broadening; and combined Doppler, natural, and collisional broadening). It is shown that there are two coexisting scales with a different behavior: the small scale is controlled by the intricate PFR details while the large scale is essentially given by the atom rest frame redistribution asymptotic. The pure Doppler and combined natural, Doppler, and collisional broadening are characterized by both small- and large-scale superdiffusive Levy flight behaviors while the combined natural and Doppler case has an anomalous small-scale behavior but a diffusive large-scale asymptotic. The common practice of assuming complete redistribution in core radiation and frequency coherence in the wings of the spectral distribution is incompatible with the breakdown of superdiffusion in combined natural and Doppler broadening conditions.