Characterizing extinction debt following habitat fragmentation using neutral theory

Habitat loss leads to species extinctions, both immediately and over the long-term as “extinction debt” is repaid. The same quantity of habitat can be lost in different spatial patterns with varying habitat fragmentation. How this translates to species loss remains an open problem requiring an understanding of the interplay between community dynamics and habitat structure across temporal and spatial scales. Here we develop formulas that characterize extinction debt in a spatial neutral model after habitat loss and fragmentation. Central to our formulas are two new metrics, which depend on properties of the taxa and landscape: “effective area”, measuring the remaining number of individuals; and “effective connectivity”, measuring individuals’ ability to disperse through fragmented habitat. This formalizes the conventional wisdom that habitat area and habitat connectivity are the two critical requirements for long term preservation of biodiversity. Our approach suggests that mechanistic fragmentation metrics help resolve debates about fragmentation and species loss

Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries

Analysis of the footwork patterns of elite wicket-keepers in cricket

In [1], a revised version of the Pole-Placement Shifting based controller tuning Algorithm (PPSA), a finite-dimensional model-matching controller tuning method for time-delay systems (TDS), was presented together with some suggestions about algorithm improvements and modifications. Its leading idea consists in the placing the dominant characteristic poles and zeros of the infinite-dimensional feedback control system with respect to the desired dynamics of the simple finite-dimensional matching model. So far, retarded TDS have been studied in the reign of the PPSA. This paper, however, brings a detailed case study on a more advanced and intricate neutral-type control feedback. Unstable controlled plant is selected in our example, in addition. The results indicate a very good applicability of the PPSA under some minor modifications of standard manipulations with the neutral-type delayed spectrum. © Springer International Publishing Switzerland 2015

[Systematic review: value of perioperative chemotherapy in the management of resectable rectal adenocarcinoma (brief report)]

International audienceAt the request of the National Thesaurus of Gastrointestinal Cancer (TNCD), the SOR program undertaken by the French federation of cancer centers and now led by the French National Cancer Institute, completed a systematic review to evaluate the value of perioperative chemotherapy in the management of resectable rectal adenocarcinoma in collaboration with clinician experts. METHODS: Results of a systematic literature search using Medline and Embase (from January 1996 to October 2007) were completed by a survey of Evidence- Based Medicine websites. All phase III randomized trials and systematic reviews comparing surgery (alone or associated with adjuvant therapy) to the same treatment plus chemotherapy, or comparing different perioperative chemotherapy modalities in patients with resectable rectal adenocarcinoma, were included in the study. The quality and clinical relevance of the trials were evaluated using validated checklists, allowing to associate each result with its level of evidence. Data synthesis was performed taking into account both efficacy and toxicity outcomes for each intervention. Finally, research recommendations were formulated. RESULTS: Of 29 studies meeting the selection criteria, 19 were included after critical methodological and clinical appraisal. As compared with preoperative radiotherapy, preoperative chemoradiotherapy with 5-fluorouracil and folinic acid does not improve overall or relapse-free survivals but decreases local recurrence rates. Postoperative chemotherapy with 5-fluorouracil and folinic acid does not improve overall or relapse-free survivals, whether the patients received preoperative radiotherapy or preoperative chemoradiotherapy, whereas it seems to decrease local recurrence rates after preoperative radiotherapy but not after preoperative chemoradiotherapy. As compared with postoperative chemoradiotherapy, preoperative chemoradiotherapy with continuous infusion of 5-fluorouracil does not improve overall or relapse-free survivals, but decreases local recurrence rates as well as acute and long-term toxicities. In the absence of preoperative radiotherapy, fluoropyrimidine-based postoperative chemotherapy improves both overall and relapse-free survivals and decreases local recurrence rates. CONCLUSIONS: Preoperative chemoradiotherapy reduces the risk of local recurrence as compared with preoperative radiotherapy or postoperative chemoradiotherapy