29 research outputs found

    Cyclic voles and shrews and non-cyclic mice in a marginal grassland within European temperate forest

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    Cyclic population dynamics of small mammals are not restricted to the boreal and arctic zones of Eurasia and North America, but long-term data series from lower latitudes are still less common. We demonstrated here the presence of periodic oscillations in small mammal populations in eastern Poland using 22-year (1986–2007) trapping data from marginal meadow and river valley grasslands located in the extensive temperate woodland of Białowieża Primeval Forest. The two most common species inhabiting meadows and river valleys, root vole Microtus oeconomus and common shrew Sorex araneus, exhibited synchronous periodic changes, characterised by a 3-year time lag as indicated by an autocorrelation function. Moreover, the cycles of these two species were synchronous within both habitats. Population dynamics of the striped field mouse Apodemus agrarius was not cyclic. However, this species regularly reached maximum density 1 year before the synchronized peak of root voles and common shrews, which may suggest the existence of interspecific competition. Dynamics of all three species was dominated by direct density-dependent process, whereas delayed density dependent feedback was significant only in the root vole and common shrew. Climatic factors acting in winter and spring (affecting mainly survival and initial reproduction rates) were more important than those acting in summer and autumn and affected significantly only the common shrew. High temperatures in winter and spring had positive effects on autumn-to-autumn changes in abundance of this species, whereas deep snow in combination with high rainfall in spring negatively affected population increase rates in common shrew

    Pooled analysis of WHO Surgical Safety Checklist use and mortality after emergency laparotomy

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    Background The World Health Organization (WHO) Surgical Safety Checklist has fostered safe practice for 10 years, yet its place in emergency surgery has not been assessed on a global scale. The aim of this study was to evaluate reported checklist use in emergency settings and examine the relationship with perioperative mortality in patients who had emergency laparotomy. Methods In two multinational cohort studies, adults undergoing emergency laparotomy were compared with those having elective gastrointestinal surgery. Relationships between reported checklist use and mortality were determined using multivariable logistic regression and bootstrapped simulation. Results Of 12 296 patients included from 76 countries, 4843 underwent emergency laparotomy. After adjusting for patient and disease factors, checklist use before emergency laparotomy was more common in countries with a high Human Development Index (HDI) (2455 of 2741, 89.6 per cent) compared with that in countries with a middle (753 of 1242, 60.6 per cent; odds ratio (OR) 0.17, 95 per cent c.i. 0.14 to 0.21, P <0001) or low (363 of 860, 422 per cent; OR 008, 007 to 010, P <0.001) HDI. Checklist use was less common in elective surgery than for emergency laparotomy in high-HDI countries (risk difference -94 (95 per cent c.i. -11.9 to -6.9) per cent; P <0001), but the relationship was reversed in low-HDI countries (+121 (+7.0 to +173) per cent; P <0001). In multivariable models, checklist use was associated with a lower 30-day perioperative mortality (OR 0.60, 0.50 to 073; P <0.001). The greatest absolute benefit was seen for emergency surgery in low- and middle-HDI countries. Conclusion Checklist use in emergency laparotomy was associated with a significantly lower perioperative mortality rate. Checklist use in low-HDI countries was half that in high-HDI countries.Peer reviewe

    Global variation in anastomosis and end colostomy formation following left-sided colorectal resection

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    Background End colostomy rates following colorectal resection vary across institutions in high-income settings, being influenced by patient, disease, surgeon and system factors. This study aimed to assess global variation in end colostomy rates after left-sided colorectal resection. Methods This study comprised an analysis of GlobalSurg-1 and -2 international, prospective, observational cohort studies (2014, 2016), including consecutive adult patients undergoing elective or emergency left-sided colorectal resection within discrete 2-week windows. Countries were grouped into high-, middle- and low-income tertiles according to the United Nations Human Development Index (HDI). Factors associated with colostomy formation versus primary anastomosis were explored using a multilevel, multivariable logistic regression model. Results In total, 1635 patients from 242 hospitals in 57 countries undergoing left-sided colorectal resection were included: 113 (6·9 per cent) from low-HDI, 254 (15·5 per cent) from middle-HDI and 1268 (77·6 per cent) from high-HDI countries. There was a higher proportion of patients with perforated disease (57·5, 40·9 and 35·4 per cent; P < 0·001) and subsequent use of end colostomy (52·2, 24·8 and 18·9 per cent; P < 0·001) in low- compared with middle- and high-HDI settings. The association with colostomy use in low-HDI settings persisted (odds ratio (OR) 3·20, 95 per cent c.i. 1·35 to 7·57; P = 0·008) after risk adjustment for malignant disease (OR 2·34, 1·65 to 3·32; P < 0·001), emergency surgery (OR 4·08, 2·73 to 6·10; P < 0·001), time to operation at least 48 h (OR 1·99, 1·28 to 3·09; P = 0·002) and disease perforation (OR 4·00, 2·81 to 5·69; P < 0·001). Conclusion Global differences existed in the proportion of patients receiving end stomas after left-sided colorectal resection based on income, which went beyond case mix alone

    Angular self-reconstruction of petal-like beams.

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    Please help populate SUNScholar with the full text of SU research output. Also - should you need this item urgently, please send us the details and we will try to get hold of the full text as quick possible. E-mail to [email protected]. Thank you.Journal Articles (subsidised)NatuurwetenskappeFisik

    What makes nearshore habitats nurseries for nekton? An emerging view of the nursery role hypothesis

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    Estuaries and other coastal habitats are considered essential for the survival of early life stages of commercial, recreational, and other ecologically important species. While early designations simply referred to habitats with higher densities of juveniles as nurseries, the definition was improved by arguing that contribution per unit area to the production of individuals that recruit to adult populations is greater, on average, in nursery habitats. However, this and related approaches typically consider critical habitats as individual, homogeneous entities that are static in nature and do not specifically incorporate important dynamics that determine nursery function. The latter include environmental variability, estuarine hydrodynamics, trophic coupling, ontogenetic habitat shifts, and spatially explicit usage of habitat patches and corridors within larger seascapes. Subsequent studies have identified important factors that regulate nursery value, and researchers working independently across the globe have not only supported the advances made in defining the processes underlying nursery function but, as set forth in this narrative, have advanced it while suggesting that much work still needs to be done to improve our understanding of the links between juvenile nekton survival and the estuarine-coastal seascape. We discuss the current nursery role hypothesis and the data supporting (or refuting) it along with the implications for management of estuarine habitats for the conservation or restoration of nursery function
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