41 research outputs found
Evolution of mitochondrial relationships and biogeography of Palearctic green toads (Bufo viridis subgroup) with insights in their genomic plasticity.
Taxa involving three bisexually reproducing ploidy levels make green toads a unique amphibian system. We put a cytogenetic dataset from Central Asia in a molecular framework and apply phylogenetic and demographic methods to data from the entire Palearctic range. We study the mitochondrial relationships of diploids to infer their phylogeography and the maternal ancestry of polyploids. Control regions (and tRNAs between ND1 and ND2 in representatives) characterize a deeply branched assemblage of twelve haplotype groups, diverged since the Lower Miocene. Polyploidy has evolved several times: Central Asian tetraploids (B. oblongus, B. pewzowi) have at least two maternal origins. Intriguingly, the mitochondrial ancestor of morphologically distinctive, sexually reproducing triploid taxa (B. pseudoraddei) from Karakoram and Hindukush represents a different lineage. We report another potential case of bisexual triploid toads (B. zugmayeri). Identical d-loops in diploids and tetraploids from Iran and Turkmenistan, which differ in morphology, karyotypes and calls, suggest multiple origins and retained polymorphism and/or hybridization. A similar system involves diploids, triploids and tetraploids from Kyrgyzstan and Kazakhstan where green toads exemplify vertebrate genomic plasticity. A new form from Sicily and its African sister species (B. boulengeri) allow internal calibration and divergence time estimates for major clades. The subgroup may have originated in Eurasia rather than Africa since the earliest diverged lineages (B. latastii, B. surdus) and earliest fossils occur in Asia. We delineate ranges, contact and hybrid zones. Phylogeography, including one of the first non-avian datasets from Central Asian high mountains, reflects Quaternary climate and glaciation
Risk profiles and one-year outcomes of patients with newly diagnosed atrial fibrillation in India: Insights from the GARFIELD-AF Registry.
BACKGROUND: The Global Anticoagulant Registry in the FIELD-Atrial Fibrillation (GARFIELD-AF) is an ongoing prospective noninterventional registry, which is providing important information on the baseline characteristics, treatment patterns, and 1-year outcomes in patients with newly diagnosed non-valvular atrial fibrillation (NVAF). This report describes data from Indian patients recruited in this registry. METHODS AND RESULTS: A total of 52,014 patients with newly diagnosed AF were enrolled globally; of these, 1388 patients were recruited from 26 sites within India (2012-2016). In India, the mean age was 65.8 years at diagnosis of NVAF. Hypertension was the most prevalent risk factor for AF, present in 68.5% of patients from India and in 76.3% of patients globally (P < 0.001). Diabetes and coronary artery disease (CAD) were prevalent in 36.2% and 28.1% of patients as compared with global prevalence of 22.2% and 21.6%, respectively (P < 0.001 for both). Antiplatelet therapy was the most common antithrombotic treatment in India. With increasing stroke risk, however, patients were more likely to receive oral anticoagulant therapy [mainly vitamin K antagonist (VKA)], but average international normalized ratio (INR) was lower among Indian patients [median INR value 1.6 (interquartile range {IQR}: 1.3-2.3) versus 2.3 (IQR 1.8-2.8) (P < 0.001)]. Compared with other countries, patients from India had markedly higher rates of all-cause mortality [7.68 per 100 person-years (95% confidence interval 6.32-9.35) vs 4.34 (4.16-4.53), P < 0.0001], while rates of stroke/systemic embolism and major bleeding were lower after 1 year of follow-up. CONCLUSION: Compared to previously published registries from India, the GARFIELD-AF registry describes clinical profiles and outcomes in Indian patients with AF of a different etiology. The registry data show that compared to the rest of the world, Indian AF patients are younger in age and have more diabetes and CAD. Patients with a higher stroke risk are more likely to receive anticoagulation therapy with VKA but are underdosed compared with the global average in the GARFIELD-AF. CLINICAL TRIAL REGISTRATION-URL: http://www.clinicaltrials.gov. Unique identifier: NCT01090362
Objectivity, control and adaptability in corporate governance
Countries appear to differ considerably in the basic orientations oftheir corporate governance structures. We postulatethe trade-off between "objectivity" and "proximity" as fundamental tothe corporate governance debate. We stress thevalue of objectivity that comes with distance (e.g. the marketoriented U.S. system), and the value of better informationthat comes with proximity (e.g. the more intrusive ContinentalEuropean model).A superior corporate governance arrangement must balance thebenefits of proximity and objectivity. In this context,we also discuss the ways in which investors have "contracted around"the flaws in their own corporate governancesystems, pointing at the "adaptability" of different arrangements
Objectivity, proximity and adaptability in corporate governance
Available from British Library Document Supply Centre-DSC:3597.9512(2257) / BLDSC - British Library Document Supply CentreSIGLEGBUnited Kingdo
The phylogeny of Mediterranean tortoises and their close relatives based on complete mitochondrial genome sequences from museum specimens
As part of an ongoing project to generate a mitochondrial database for terrestrial tortoises based on museum specimens, the complete mitochondrial genome sequences of 10 species and a ∼14 kb sequence from an eleventh species are reported. The sampling of the present study emphasizes Mediterranean tortoises (genus Testudo and their close relatives). Our new sequences are aligned, along with those of two testudinoid turtles from GenBank, Chrysemys picta and Mauremys reevesii, yielding an alignment of 14,858 positions, of which 3238 are parsimony informative. We develop a phylogenetic taxonomy for Testudo and related species based on well-supported, diagnosable clades. Several well-supported nodes are recovered, including the monophyly of a restricted Testudo, T. kleinmanni + T. marginata (the Chersus clade), and the placement of the enigmatic African pancake tortoise (Malacochersus tornieri) within the predominantly Palearctic greater Testudo group (Testudona tax. nov.). Despite the large amount of sequence reported, there is low statistical support for some nodes within Testudona and so we do not propose names for those groups. A preliminary and conservative estimation of divergence times implies a late Miocene diversification for the testudonan clade (6-10 million years ago), matching their first appearance in the fossil record. The multi-continental distribution of testudonan turtles can be explained by the establishment of permanent connections between Europe, Africa, and Asia at this time. The arrival of testudonan turtles to Africa occurred after one or more initial tortoise invasions gave rise to the diverse (>25 species) 'Geochelone complex.' Two unusual genomic features are reported for the mtDNA of one tortoise, M. tornieri: (1) nad4 has a shift of reading frame that we suggest is resolved by translational frameshifting of the mRNA on the ribosome during protein synthesis and (2) there are two copies of the control region and trnF, with the latter having experienced multiple-nucleotide substitutions in a pattern suggesting that each is being maintained by selection. © 2005 Elsevier Inc. All rights reserved
An Examination of the Equity Market Response to The Gramm-Leach-Bliley Act Across Commercial Banking, Investment Banking, and Insurance Firms
This paper examines the wealth effects of the events surrounding the passage of the Gramm-Leach-Bliley Act of 1999 and changes in systematic risk from the pre-Act period to the post-Act period for commercial banks, investment banks, and insurance firms. The results suggest that investment banks and insurance firms are better positioned to exploit the benefits of product-line diversification opportunities allowed by the legislation compared to commercial banks that experience no significant market reaction. Further evidence indicates a significant risk shift and overall reduction in riskiness for the financial sectors under consideration around the event period. Copyright 2006 The Authors Journal compilation (c) 2006 Blackwell Publishing Ltd.
Corporate Governance and Bank Performance in Emerging Markets: Evidence from Russia and Ukraine
Short- and Long-Term Effects of Multimarket Trading
We analyze short- and long-term effects of multimarket trading by examining the entries of multiple markets into transacting three ETFs, DIA, QQQ, and SPY. We find that large-scale entries improve overall market quality, while small-scale entries have ambiguous effects. Our results show that the competition effect dominates the fragmentation effect over a long horizon and that market fragmentation leads to a decline in trading costs. Further, we find that the order handling rules help mitigate the fragmentation effect and facilitate the competition effect. We do not find that multimarket trading harms price efficiency or increases price volatility. Copyright 2007, The Eastern Finance Association.