A sub-product construction of Poincare-Einstein metrics

Given any two Einstein (pseudo-)metrics, with scalar curvatures suitably related, we give an explicit construction of a Poincar\'e-Einstein (pseudo-)metric with conformal infinity the conformal class of the product of the initial metrics. We show that these metrics are equivalent to ambient metrics for the given conformal structure. The ambient metrics have holonomy that agrees with the conformal holonomy. In the generic case the ambient metric arises directly as a product of the metric cones over the original Einstein spaces. In general the conformal infinity of the Poincare metrics we construct is not Einstein, and so this describes a class of non-conformally Einstein metrics for which the (Fefferman-Graham) obstruction tensor vanishes.Comment: 23 pages Minor correction to section 5. References update

Guiding principles for rewilding

There has been much recent interest in the concept of rewilding as a tool for nature conservation, but also confusion over the idea, which has limited its utility. We developed a unifying definition and 10 guiding principles for rewilding through a survey of 59 rewilding experts, a summary of key organizations’ rewilding visions, and workshops involving over 100 participants from around the world. The guiding principles convey that rewilding exits on a continuum of scale, connectivity, and level of human influence and aims to restore ecosystem structure and functions to achieve a self-sustaining autonomous nature. These principles clarify the concept of rewilding and improve its effectiveness as a tool to achieve global conservation targets, including those of the UN Decade on Ecosystem Restoration and post-2020 Global Biodiversity Framework. Finally, we suggest differences in rewilding perspectives lie largely in the extent to which it is seen as achievable and in specific interventions. An understanding of the context of rewilding projects is the key to success, and careful site-specific interpretations will help achieve the aims of rewilding

Morbidity and development in childhood of infants born after temporising treatment of early onset pre-eclampsia.

Item does not contain fulltextOBJECTIVE: To assess morbidity and development in childhood of infants born after temporising management of severe early onset pre-eclampsia. DESIGN: Cohort study with matched controls. SETTING: University centre for high risk obstetrics. SAMPLES: Three groups of neonates matched for gender and year of birth: one born after temporising treatment of severe early onset (<32 weeks) pre-eclampsia with an average delay of delivery of two weeks (n= 193); one born at the duration of pregnancy [1 week] of the pre-eclamptic mother on admission (control group I, n = 192); and one born at the same gestational age [1 week] as the infant of the pre-eclamptic mother (control group II, n= 189). METHOD: Follow up at four years of age or more using medical records and questionnaires. MAIN OUTCOME MEASURES: The presence of various morbidities including mental retardation, cerebral palsy, motor skill problems, visual handicap, hearing loss, speech and language problems, education level and acute or chronic respiratory problems. RESULTS: Median follow up of seven years (range 4-12) was achieved in 159 infants in the study group (83%), 122 in control group I (64%) and 110 in control group II (58%). Missing data analysis showed no differences in neonatal characteristics and morbidity between infants with and without follow up in the study group. All major and minor handicaps were less frequent in the study group than in control group I but statistical significance was reached only for acute and chronic respiratory disorders in the study group (13.8%) compared with control group I (27%). CONCLUSION: Average delay of delivery of two weeks with temporising management in severe early onset pre-eclampsia is associated with a reduced risk of respiratory disorders in childhood