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Consistent phenological shifts in the making of a biodiversity hotspot: the Cape flora
Background
The best documented survival responses of organisms to past climate change on short (glacial-interglacial) timescales are distributional shifts. Despite ample evidence on such timescales for local adaptations of populations at specific sites, the long-term impacts of such changes on evolutionary significant units in response to past climatic change have been little documented. Here we use phylogenies to reconstruct changes in distribution and flowering ecology of the Cape flora - South Africa's biodiversity hotspot - through a period of past (Neogene and Quaternary) changes in the seasonality of rainfall over a timescale of several million years.
Results
Forty-three distributional and phenological shifts consistent with past climatic change occur across the flora, and a comparable number of clades underwent adaptive changes in their flowering phenology (9 clades; half of the clades investigated) as underwent distributional shifts (12 clades; two thirds of the clades investigated). Of extant Cape angiosperm species, 14-41% have been contributed by lineages that show distributional shifts consistent with past climate change, yet a similar proportion (14-55%) arose from lineages that shifted flowering phenology.
Conclusions
Adaptive changes in ecology at the scale we uncover in the Cape and consistent with past climatic change have not been documented for other floras. Shifts in climate tolerance appear to have been more important in this flora than is currently appreciated, and lineages that underwent such shifts went on to contribute a high proportion of the flora's extant species diversity. That shifts in phenology, on an evolutionary timescale and on such a scale, have not yet been detected for other floras is likely a result of the method used; shifts in flowering phenology cannot be detected in the fossil record
HIV Infection Is Associated with a Lower Incidence of Constriction in Presumed Tuberculous Pericarditis: A Prospective Observational Study
The original publication is available at http:/www.plosone.orgBackground: Pericardial constriction is a serious complication of tuberculous pericardial effusion that occurs in up to a quarter of patients despite anti-tuberculosis chemotheraphy. The impact of human immunodeficiency virus (HIV) infection on the incidence of constrictive pericarditis following tuberculous pericardial effusion is unknown. Methods and Results: We conducted a prospective observational study to determine the association between HIV infection and the incidence of constrictive pericarditis among 185 patients (median age 33 years) with suspected tuberculous pericardial effusion. These patients were recruited consecutively between March and October 2004 on commencement of anti-tuberculosis treatment, from 15 hospitals in Cameroon, Nigeria and South Africa. Surviving patients (N = 119) were assessed for clinical evidence of constrictive pericarditis at 3 and 6 months of follow-up. Clinical features of HIV infection were present in 42 (35.2%) of the 119 patients at enrolment into the study.66 of the 119 (56.9%) patients consented to HIV testing at enrolment. During the 6 months of follow-up, a clinical diagnosis of constrictive pericarditis was made in 13 of the 119 patients (10.9%, 95% confidence interval [CI] 5.9-18%). Patients with clinical features of HIV infection appear less likely to develop constriction than those without (4.8% versus 14.3%; P = 0.08). None of the 33 HIV seropositive patients developed constriction, but 8 (24.2%, 95%CI 11.1-42.3%)of the 33 HIV seronegative patients did (P = 0.005). In a multivariate logistic regression model adjusting simultaneously for several baseline characteristics, only clinical signs of HIV infection were significantly associated with a lower risk of constriction (odd ratio 0.14, 95% CI 0.02-0.87, P = 0.035). Conclusions: These data suggest that HIV infection is associated with a lower incidence of pericardial constriction in patients with presumed tuberculous pericarditis. © 2008 Ntsekhe et al.This study was funded, in part, through research grants from the University of Cape Town, the Medical Scholarships for South African Blacks (MESAB), the Medical Research Council of South Africa, the National Research Foundation of South Africa.Publishers' versio
Extinction Risk and Diversification Are Linked in a Plant Biodiversity Hotspot
Plant extinction risks in the Cape, South Africa differ from those for
vertebrates worldwide, with young and fast-evolving plant lineages marching
towards extinction at the fastest rate, but independently of human effects
Current practice and surgical outcomes of neoadjuvant chemotherapy for early breast cancer : UK NeST study
Funding Information: This work was funded by a grant from the Association of Breast SurgeryPeer reviewedPublisher PD
FIDEL—a retrovirus-like retrotransposon and its distinct evolutionary histories in the A- and B-genome components of cultivated peanut
In this paper, we describe a Ty3-gypsy retrotransposon from allotetraploid peanut (Arachis hypogaea) and its putative diploid ancestors Arachis duranensis (A-genome) and Arachis ipaënsis (B-genome). The consensus sequence is 11,223 bp. The element, named FIDEL (Fairly long Inter-Dispersed Euchromatic LTR retrotransposon), is more frequent in the A- than in the B-genome, with copy numbers of about 3,000 (±950, A. duranensis), 820 (±480, A. ipaënsis), and 3,900 (±1,500, A. hypogaea) per haploid genome. Phylogenetic analysis of reverse transcriptase sequences showed distinct evolution of FIDEL in the ancestor species. Fluorescent in situ hybridization revealed disperse distribution in euchromatin and absence from centromeres, telomeric regions, and the nucleolar organizer region. Using paired sequences from bacterial artificial chromosomes, we showed that elements appear less likely to insert near conserved ancestral genes than near the fast evolving disease resistance gene homologs. Within the Ty3-gypsy elements, FIDEL is most closely related with the Athila/Calypso group of retrovirus-like retrotransposons. Putative transmembrane domains were identified, supporting the presence of a vestigial envelope gene. The results emphasize the importance of FIDEL in the evolution and divergence of different Arachis genomes and also may serve as an example of the role of retrotransposons in the evolution of legume genomes in general
Effects of hospital facilities on patient outcomes after cancer surgery: an international, prospective, observational study
Background Early death after cancer surgery is higher in low-income and middle-income countries (LMICs) compared with in high-income countries, yet the impact of facility characteristics on early postoperative outcomes is unknown. The aim of this study was to examine the association between hospital infrastructure, resource availability, and processes on early outcomes after cancer surgery worldwide.Methods A multimethods analysis was performed as part of the GlobalSurg 3 study-a multicentre, international, prospective cohort study of patients who had surgery for breast, colorectal, or gastric cancer. The primary outcomes were 30-day mortality and 30-day major complication rates. Potentially beneficial hospital facilities were identified by variable selection to select those associated with 30-day mortality. Adjusted outcomes were determined using generalised estimating equations to account for patient characteristics and country-income group, with population stratification by hospital.Findings Between April 1, 2018, and April 23, 2019, facility-level data were collected for 9685 patients across 238 hospitals in 66 countries (91 hospitals in 20 high-income countries; 57 hospitals in 19 upper-middle-income countries; and 90 hospitals in 27 low-income to lower-middle-income countries). The availability of five hospital facilities was inversely associated with mortality: ultrasound, CT scanner, critical care unit, opioid analgesia, and oncologist. After adjustment for case-mix and country income group, hospitals with three or fewer of these facilities (62 hospitals, 1294 patients) had higher mortality compared with those with four or five (adjusted odds ratio [OR] 3.85 [95% CI 2.58-5.75]; p<0.0001), with excess mortality predominantly explained by a limited capacity to rescue following the development of major complications (63.0% vs 82.7%; OR 0.35 [0.23-0.53]; p<0.0001). Across LMICs, improvements in hospital facilities would prevent one to three deaths for every 100 patients undergoing surgery for cancer.Interpretation Hospitals with higher levels of infrastructure and resources have better outcomes after cancer surgery, independent of country income. Without urgent strengthening of hospital infrastructure and resources, the reductions in cancer-associated mortality associated with improved access will not be realised
Emplotment as Epic in Archaeological Writing: The Site Monograph as Narrative
To emplot a narrative as epic is to present a story of vast scope and multiple plots as a legitimate member of a tradition of other such stories. This article argues that emplotment as epic is the broadest of three levels of plot in archaeological writings. At that level, the site monograph emerges as a characteristically archaeological form of narrative, fundamental to archaeology as a discipline and a source of chronic anxiety for archaeologists. The ‘stories’ told in site monographs are epic in length, diversity of materials covered and multiplicity of themes, plots and authors. Indeed, the more complexities of that sort the better, since those are features that help to emplot the work as good archaeology
A Habermasian perspective on joint meaning making online: What does it offer and what are the difficulties?
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