Monotonic Distributive Semilattices

In the study of algebras related to non-classical logics, (distributive) semilattices are always present in the background. For example, the algebraic semantic of the {→, ∧, ⊤}-fragment of intuitionistic logic is the variety of implicative meet-semilattices (Chellas 1980; Hansen 2003). In this paper we introduce and study the class of distributive meet-semilattices endowed with a monotonic modal operator m. We study the representation theory of these algebras using the theory of canonical extensions and we give a topological duality for them. Also, we show how our new duality extends to some particular subclasses.Fil: Celani, Sergio Arturo. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Ciencias Exactas. Departamento de Matemática; ArgentinaFil: Menchón, María Paula. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Ciencias Exactas. Departamento de Matemática; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Modelling Nondeterminism

This paper consists of some preliminary steps towards the construction of a new calculus for modelling nondeterministic speci cations as multirelations. The model is appealing because it combines some of the merits of the existing models of relations and predicate transformers. Like relations, multirelations model speci cations from initial to nal state, and like predicate transformers, they can model two kinds of nondeterminism within a single framework. This is achieved by mapping input values to postconditions rather than output values. So the multirelational model is more expressive than that of relations, but not quite as transparent. Therefore we recommend its use only for the description of systems that cannot be expressed more simply using ordinary relation

Association of early postnatal transfer and birth outside a tertiary hospital with mortality and severe brain injury in extremely preterm infants: observational cohort study with propensity score matching

Objective To determine if postnatal transfer or birth in a non-tertiary hospital is associated with adverse outcomes. Design Observational cohort study with propensity score matching. Setting National health service neonatal care in England; population data held in the National Neonatal Research Database. Participants Extremely preterm infants born at less than 28 gestational weeks between 2008 and 2015 (n=17 577) grouped based on birth hospital and transfer within 48 hours of birth: upward transfer (non-tertiary to tertiary hospital, n=2158), non-tertiary care (born in non-tertiary hospital; not transferred, n=2668), and controls (born in tertiary hospital; not transferred, n=10 866). Infants were matched on propensity scores and predefined background variables to form subgroups with near identical distributions of confounders. Infants transferred between tertiary hospitals (horizontal transfer) were separately matched to controls in a 1:5 ratio. Main outcome measures Death, severe brain injury, and survival without severe brain injury. Results 2181 infants, 727 from each group (upward transfer, non-tertiary care, and control) were well matched. Compared with controls, infants in the upward transfer group had no significant difference in the odds of death before discharge (odds ratio 1.22, 95% confidence interval 0.92 to 1.61) but significantly higher odds of severe brain injury (2.32, 1.78 to 3.06; number needed to treat (NNT) 8) and significantly lower odds of survival without severe brain injury (0.60, 0.47 to 0.76; NNT 9). Compared with controls, infants in the non-tertiary care group had significantly higher odds of death (1.34, 1.02 to 1.77; NNT 20) but no significant difference in the odds of severe brain injury (0.95, 0.70 to 1.30) or survival without severe brain injury (0.82, 0.64 to 1.05). Compared with infants in the upward transfer group, infants in the non-tertiary care group had no significant difference in death before discharge (1.10, 0.84 to 1.44) but significantly lower odds of severe brain injury (0.41, 0.31 to 0.53; NNT 8) and significantly higher odds of survival without severe brain injury (1.37, 1.09 to 1.73; NNT 14). No significant differences were found in outcomes between the horizontal transfer group (n=305) and controls (n=1525). Conclusions In extremely preterm infants, birth in a non-tertiary hospital and transfer within 48 hours are associated with poor outcomes when compared with birth in a tertiary setting. We recommend perinatal services promote pathways that facilitate delivery of extremely preterm infants in tertiary hospitals in preference to postnatal transfer

Trends in Outcomes for Neonates Born Very Preterm and Very Low Birth Weight in 11 High-Income Countries

OBJECTIVE: To evaluate outcome trends of neonates born very preterm in 11 high-income countries participating in the International Network for Evaluating Outcomes of neonates. STUDY DESIGN: In a retrospective cohort study, we included 154 233 neonates admitted to 529 neonatal units between January 1, 2007, and December 31, 2015, at 24(0/7) to 31(6/7) weeks of gestational age and birth weight <1500 g. Composite outcomes were in-hospital mortality or any of severe neurologic injury, treated retinopathy of prematurity, and bronchopulmonary dysplasia (BPD); and same composite outcome excluding BPD. Secondary outcomes were mortality and individual morbidities. For each country, annual outcome trends and adjusted relative risks comparing epoch 2 (2012-2015) to epoch 1 (2007-2011) were analyzed. RESULTS: For composite outcome including BPD, the trend decreased in Canada and Israel but increased in Australia and New Zealand, Japan, Spain, Sweden, and the United Kingdom. For composite outcome excluding BPD, the trend decreased in all countries except Spain, Sweden, Tuscany, and the United Kingdom. The risk of composite outcome was lower in epoch 2 than epoch 1 in Canada (adjusted relative risks 0.78; 95% CI 0.74-0.82) only. The risk of composite outcome excluding BPD was significantly lower in epoch 2 compared with epoch 1 in Australia and New Zealand, Canada, Finland, Japan, and Switzerland. Mortality rates reduced in most countries in epoch 2. BPD rates increased significantly in all countries except Canada, Israel, Finland, and Tuscany. CONCLUSIONS: In most countries, mortality decreased whereas BPD increased for neonates born very preterm

The International Network for Evaluating Outcomes (iNeo) of neonates: evolution, progress and opportunities

Neonates born very preterm (before 32 weeks’ gestational age), are a significant public health concern because of their high-risk of mortality and life-long disability. In addition, caring for very preterm neonates can be expensive, both during their initial hospitalization and their long-term cost of permanent impairments. To address these issues, national and regional neonatal networks around the world collect and analyse data from their constituents to identify trends in outcomes, and conduct benchmarking, audit and research. Improving neonatal outcomes and reducing health care costs is a global problem that can be addressed using collaborative approaches to assess practice variation between countries, conduct research and implement evidence-based practices. The International Network for Evaluating Outcomes (iNeo) of neonates was established in 2013 with the goal of improving outcomes for very preterm neonates through international collaboration and comparisons. To date, 10 national or regional population-based neonatal networks/datasets participate in iNeo collaboration. The initiative now includes data on >200,000 very preterm neonates and has conducted important epidemiological studies evaluating outcomes, variations and trends. The collaboration has also surveyed >320 neonatal units worldwide to learn about variations in practices, healthcare service delivery, and physical, environmental and manpower related factors and support services for parents. The iNeo collaboration serves as a strong international platform for Neonatal-Perinatal health services research that facilitates international data sharing, capacity building, and global efforts to improve very preterm neonate care