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51.
Wind-borne insects mediate directional pollen transfer between desert fig trees 160 kilometers apart
Sophia Ahmed Stephen G. Compton Roger K. Butlin Philip M. Gilmartin 《Proceedings of the National Academy of Sciences of the United States of America》2009,106(48):20342-20347
The question of how far pollen can move between plants has implications for topics as diverse as habitat fragmentation, conservation management, and the containment of genetically modified crops. The monoecious African fig tree Ficus sycomorus L. relies on the small, short-lived, night-flying, host-specific fig wasp Ceratosolen arabicus Mayr for pollination. We used microsatellite markers to characterize a geographically isolated riparian population of F. sycomorus growing along the Ugab River in the Namib Desert, Namibia, together with paternity analysis of seedlings from known mothers, to map pollen movement within this population. In this way we tracked insect movements between individually recognizable trees by means of their pollen cargo and documented the movement of C. arabicus between known trees separated by more than 160 km, with a mean distance for confirmed successful pollination events of 88.6 km. The predominant observed movement of pollinators was in a westerly direction, toward the sea, reflecting seasonal nighttime wind direction and the wind-borne dispersal of fig wasps. Our results suggest the existence of an extensive panmictic population of trees that are well suited to overcome the effects of geographical isolation. 相似文献
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Dimitrios Papadimas Tilemachos Paraskeuopoulos Sophia Anagnostopoulou 《Clinical anatomy (New York, N.Y.)》2009,22(7):826-833
Bilateral dissection of 15 formalin embalmed cadaver legs was performed in order to study the anatomic pattern of the peroneal artery (PA) and its cutaneous perforating vessels (CB). The total number of CB from the PA was 125 or an average of 4.17 branches per leg. CB were distributed in the superoinferior axis between 18.25 and 84.25% of the length of the fibula and their average length was 5 ± 1.8 cm. 86/125 (68.8%) of the CB were classified as myocutaneous branches (MC) that penetrated muscle before reaching the skin, whereas 39/125 (31.2%) were septocutaneous branches (SC) that passed through the intermuscular septum. The mean distance between the posterior border of the fibula and the site where the perforators emerged was 1.88 ± 0.79 cm for the SC and 1.21 ± 0.87 cm for the MC. These anatomic findings should encourage the surgeon to design the skin paddle in the boundary between the middle and the distal third of the fibular length about 2 cm behind the posterior fibular border on the posterolateral leg, where the number of CB is maximal. Clin. Anat. 22:826–833, 2009. © 2009 Wiley‐Liss, Inc. 相似文献
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Alison J. Wright Sophia C. L. Whitwell Chika Takeichi Matthew Hankins Theresa M. Marteau 《British journal of health psychology》2009,14(1):107-125
Objectives. Numeracy, the ability to process basic mathematical concepts, may affect responses to graphical displays of health risk information. Displays of probabilistic risk information using grouped dots are easier to understand than displays using dispersed dots. However, dispersed dots may better convey the randomness with which health threats occur, so increasing perceived susceptibility. We hypothesized that low numeracy participants would better understand risks presented using grouped dot displays, while high numeracy participants would have good understanding, regardless of display type. Moreover, we predicted that dispersed dot displays, in contrast to grouped dot displays, would increase risk perceptions and worry only for highly numerate individuals. Design and method. One hundred and forty smokers read vignettes asking them to imagine being at risk of Crohn's disease, in a 2(display type: dispersed/grouped dots)×3(risk magnitude: 3%/6%/50%)×2(numeracy: high/low) design. They completed measures of risk comprehension, perceived susceptibility and worry. Results. More numerate participants had better objective risk comprehension, but this effect was not moderated by display type. There was marginally significant support for the predicted numeracy × display type interaction for worry about Crohn's disease, but not for perceived susceptibility to the condition. Conclusions. Dispersed dot displays somewhat increase worry in highly numerate individuals, but only numeracy influenced objective risk comprehension. The most effective display type for communicating risk information will depend on the numeracy of the population and the goal(s) of the communication. 相似文献
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Lorraine Lok Wing Chiang Christien Li Kathryn L Hong Winsy Sin Hui Sze Yi Beh Mengqi Gong Tong Liu Guangping Li Yunlong Xia Jeffery Ho Leonardo Roever Sophia Duong Grace Huang Gary Tse Adrian Baranchuk Benedict M. Glover International Health Informatics Study Network 《Clinical cardiology》2021,44(6):814
BackgroundConventional catheter ablation involves prolonged exposure to ionizing radiation, potentially leading to detrimental health effects. Minimal fluoroscopy (MF) represents a safer alternative, which should be explored. Data on the safety and efficacy of this technique are limited.HypothesisOur hypothesis is that MF is of equal efficacy and safety to conventional catheter ablation with the use of fluoroscopy by performing a meta‐analysis of both randomized controlled trials (RCTs) and real‐world registry studies.MethodsPubmed and Embase were searched from their inception to July 2020 for RCTs, cohort and observational studies that assessed the outcomes of catheter ablation using a MF technique versus the conventional approach.ResultsFifteen studies involving 3795 patients were included in this meta‐analysis. There was a significant reduction in fluoroscopy and procedural time with no difference in acute success (odds ratio [OR]:0.74, 95% CI: 0.50–1.10, p = .14), long‐term success (OR:0.92, 95% CI: 0.65–1.31, p = .38), arrhythmia recurrence (OR:1.24, 95% CI: 0.75–2.06, p = .97) or rate of complications. (OR:0.83, 95% CI: 0.46–1.48, p = .65). Additionally sub‐group analysis for those undergoing catheter ablation for atrial fibrillation (AF) did not demonstrate a difference in success or complication rates (OR:0.86, 95% CI: 0.30–2.42, p = .77). Multivariate meta‐regression did not identify the presence of moderator variables.ConclusionThis updated meta‐analysis demonstrated an overall reduction in procedural and fluoroscopy time for those undergoing a minimal fluoroscopic approach. There was no significant difference in either acute or chronic success rates or complications between a MF approach and conventional approach for the management of all arrhythmias including those undergoing catheter ablation for AF. 相似文献
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