The Effect of Social Feedback in a Reddit Weight Loss Community

This is a preprint of an article appearing at ACM Digital Health 201

Population‐based cohort study of outcomes following cholecystectomy for benign gallbladder diseases

Background The aim was to describe the management of benign gallbladder disease and identify characteristics associated with all‐cause 30‐day readmissions and complications in a prospective population‐based cohort. Methods Data were collected on consecutive patients undergoing cholecystectomy in acute UK and Irish hospitals between 1 March and 1 May 2014. Potential explanatory variables influencing all‐cause 30‐day readmissions and complications were analysed by means of multilevel, multivariable logistic regression modelling using a two‐level hierarchical structure with patients (level 1) nested within hospitals (level 2). Results Data were collected on 8909 patients undergoing cholecystectomy from 167 hospitals. Some 1451 cholecystectomies (16·3 per cent) were performed as an emergency, 4165 (46·8 per cent) as elective operations, and 3293 patients (37·0 per cent) had had at least one previous emergency admission, but had surgery on a delayed basis. The readmission and complication rates at 30 days were 7·1 per cent (633 of 8909) and 10·8 per cent (962 of 8909) respectively. Both readmissions and complications were independently associated with increasing ASA fitness grade, duration of surgery, and increasing numbers of emergency admissions with gallbladder disease before cholecystectomy. No identifiable hospital characteristics were linked to readmissions and complications. Conclusion Readmissions and complications following cholecystectomy are common and associated with patient and disease characteristics

Rapid responses of root traits and productivity to phosphorus and cation additions in a tropical lowland forest in Amazonia

This is the author accepted manuscript. The final version is available from Wiley via the DOI in this recordSoil nutrient availability can strongly affect root traits. In tropical forests, phosphorus (P) is often considered the main limiting nutrient for plants. However, support for the P paradigm is limited, and N and cations might also control tropical forests functioning. We used a large-scale experiment to determine how the factorial addition of nitrogen (N), P and cations affected root productivity and traits related to nutrient acquisition strategies (morphological traits, phosphatase activity, arbuscular mycorrhizal colonisation and nutrient contents) in a primary rainforest growing on low-fertility soils in Central Amazonia after one year of fertilisation. Multiple root traits and productivity were affected. Phosphorus additions increased annual root productivity and root diameter, but decreased root phosphatase activity. Cation additions increased root productivity at certain times of year, also increasing root diameter and mycorrhizal colonisation. P and cation additions increased their element concentrations in root tissues. No responses were detected with N addition. Here we show that rock-derived nutrients determine root functioning in low-fertility Amazonian soils, demonstrating not only the hypothesised importance of P, but also highlighting the role of cations. The changes in fine root traits and productivity indicate that even slow-growing tropical rainforests can respond rapidly to changes in resource availability.Brazilian National Council for Scientific and 551 Technological Development (CNPq)Natural Environment Research Council (NERC)Australian Research Council (ARC)European Research Council (ERC

Myopia during emergency improvisation: lessons from a catastrophic wildfire

Purpose: The purpose of this paper is to explore how a number of processes joined to create the microlevel strategies and procedures that resulted in the most lethal and tragic forest fire in Portugal's history, recalled as the EN236-1 road tragedy in the fire of Pedrógão Grande. Design/methodology/approach: Using an inductive theory development approach, the authors consider how the urgency and scale of perceived danger coupled with failures of system-wide communication led fire teams to improvise repeatedly. Findings: The paper shows how structure collapse led teams to use only local information prompting acts of improvisational myopia, in the particular shape of corrosive myopia, and how a form of incidental improvisation led to catastrophic results. Practical implications: The research offers insights into the dangers of improvisation arising from corrosive myopia, identifying ways to minimize them with the development of improvisation practices that allow for the creation of new patterns of action. The implications for managing surprise through improvisation extend to risk contexts beyond wildfires. Originality/value: The paper stands out for showing the impact of improvisational myopia, especially in its corrosive form, which stands in stark contrast to the central role of attention to the local context highlighted in previous research on improvisation. At the same time, by exploring the effects of incidental improvisation, it also departs from the agentic conception of improvisation widely discussed in the improvisation literature