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The late Cretaceous Corsinipollenites from central India and its nearest living fossil pollen Ludwigia from Pleistocene Karewa sediments in Kashmir shows morphometrical affinities with pollen of seven extant Ludwigia species (L. octovalvis (Jacq) P.H. Raven , L. octovalvis subsp. sessiliflora (M.Micheli) Raven , L. adscendens (L.) H. Hara , L. perennis (L.), L. hyssopifolia (G.Don) Exell , L. peruviana (L.) H. Hara and L. decurrens Walt.) commonly growing in swampy ecosystems of India. The Field Emission Scanning Electron Microscope (FESEM) and Light Microscope (LM) study draws plausible lineage of extant Ludwigia species with that of fossil specimens recovered at two different time frames based on similarities in pollen morphometry. The pollen aperture and its character along with the sexine pattern were main identifiable features to distinguish different species of extant/fossil Ludwigia pollen. The aspidote aperture varies from brevi-colporate to slit-like colpi (colporate). The sexine is stenopalynous type characterized by rugulate to reti-rugulate pattern. The multivariate principal component analysis (PCA) was applied on the numerical data obtained from pollen morphometry of living and fossil Ludwigia spp. The Pleistocene Ludwigia morphotype with slit-like colpi shows close proximity to L. octovalvis, L. octovalvis subsp. sessiliflora and L. adscendens. However, Late Cretaceous, Corsinipollenitis characterized by brevicolpi is closer to L. perennis and L. hyssopifolia with respect to primary pollen characters and inferred as primitive species having lineage to the "Old World" (paleotropical) species. A short pollen key of Ludwigia spp., is presented here to enable the identification of living/fossil pollen. • Morphometry and morphology of seven extant species of Ludwigia from India. • A plausible lineage of living Ludwigia with their fossil pollen records. • Pleistocene Ludwigia and L. octovalvis subsp. sessiliflora shares similar pollen characters. • Late Cretaceous, Corsinipollenitis is similar to L. perennis and L. hyssopifolia. • Ludwigia perennis and L. hyssopifolia are primitive species having lineage to the "Old World." [ABSTRACT FROM AUTHOR]

Secondary education among lower caste adolescent girls living in rural Karnataka, South India, is characterized by high rates of school drop-out and absenteeism. A cross-sectional baseline survey (N=2275) was conducted in 2014 as part of a cluster-randomized control trial among adolescent girls (13-14 year) and their families from marginalized communities in two districts of north Karnataka. Bivariate and multivariate logistic regression models were used. Overall, 8.7% girls reported secondary school dropout and 8.1% reported frequent absenteeism (past month). In adjusted analyses, economic factors (household poverty; girls' work-related migration), social norms and practices (child marriage; value of girls' education), and school-related factors (poor learning environment and bullying/harassment at school) were associated with an increased odds of school dropout and absenteeism. Interventions aiming to increase secondary school retention among marginalized girls may require a multi-level approach, with synergistic components that address social, structural and economic determinants of school absenteeism and dropout. [ABSTRACT FROM AUTHOR]