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1.
Urban Ecosystems - The spread of the red palm weevil is now a very severe problem on a global scale. In this paper, we investigate its spread during the 2007–2013 period in a coastal urban...  相似文献   
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Local area population forecasts have a wide variety of uses in the public and private sectors. But not enough is known about the errors of such forecasts, particularly over the longer term (20 years or more). Understanding past errors is valuable for both forecast producers and users. This paper (i) evaluates the forecast accuracy of past local area population forecasts published by Australian State and Territory Governments over the last 30 years and (ii) illustrates the ways in which past error distributions can be employed to quantify the uncertainty of current forecasts. Population forecasts from the past 30 years were sourced from State and Territory Governments. Estimated resident populations to which the projections were compared were created for the geographical regions of the past projections. The key features of past forecast error patterns are described. Forecast errors mostly confirm earlier findings with regard to the relationship between error and length of projection horizon and population size. The paper then introduces the concept of a forecast ‘shelf life’, which indicates how far into the future a forecast is likely to remain reliable. It also illustrates how past error distributions can be used to create empirical prediction intervals for current forecasts. These two complementary measures provide a simple way of communicating the likely magnitude of error that can be expected with current local area population forecasts.  相似文献   
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Lifetime Data Analysis - Frailty models are generally used to model heterogeneity between the individuals. The distribution of the frailty variable is often assumed to be continuous. However, there...  相似文献   
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We contribute to the literature of the country, industry and firm effects on performance by developing an autoregressive cross-classified mixed-effect linear model that examines heterogeneity in the profitability of corporations in emerging and developed economies, as well as corporations located in different supranational regions. To this purpose, we simultaneously decompose abnormal returns into permanent and transitory components at the firm, industry, country and industry–country levels. We find that firms in emerging countries have significantly higher rates of performance persistence and different sources of persistence compared to firms located in developed countries. These differences are also evident between different supranational regions and countries at different levels of institutional development.

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We examined whether fathers’ residency modified the associations among mothers’ supportiveness, father involvement, children’s negative emotionality during toddlerhood and children’s academic skills in pre‐kindergarten via children’s self‐regulation. Participants were 2,291 mothers (Mage = 23.24 years) and children (Mage = 14.99 months at Wave 1; 50.7% girls) in the Early Head Start Research and Evaluation Project. Results revealed distinctive associations by fathers’ residency: self‐regulation mediated the association between mothers’ supportiveness and academic skills only in resident‐father‐families. Self‐regulation mediated the association between negative emotionality and academic skills only in nonresident‐father‐families. The findings highlight the family processes of mothers, fathers, and children in low‐income family contexts that contribute to children’s academic skills, and how those family processes may vary by fathers’ residency status.  相似文献   
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Urban Ecosystems - Latin America and the Caribbean (LAC) is one of the most urbanized and biologically diverse regions in the world but is often characterized by weak environmental governance and...  相似文献   
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In this work, we propose an optimization approach for constructing various classes of circulant combinatorial designs that can be defined in terms of autocorrelation. The problem is formulated as a so-called feasibility problem having three sets, to which the Douglas–Rachford projection algorithm is applied. The approach is illustrated on three different classes of circulant combinatorial designs: circulant weighing matrices, D-optimal matrices of circulant type, and Hadamard matrices with two circulant cores. Furthermore, we explicitly construct two new circulant weighing matrices, a CW(126, 64) and a CW(198, 100), whose existence was previously marked as unresolved in the most recent version of Strassler’s table.  相似文献   
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Background

Ice-pack is widely used for alleviating postpartum perineal pain sustained after birth related perineal trauma. However, it lacks robust evidence on timing and frequency of applications, to ensure the effective and safe use of this therapy.

Aims

To evaluate if a 10 min ice-pack application relieved postpartum perineal pain and if the analgesic effect was maintained for up to 2 h.

Methods

A randomised controlled trial conducted from December 2012 to February 2013 with 69 primiparous women ≥18 years old, 6–24 h postpartum, with perineal pain ≥3, who had not received anti-inflammatory medication or analgesics after childbirth, who were randomised to a single ice-pack application on the perineum for 10 min or standard care. The primary and secondary outcomes were a reduction ≥30% in perineal pain intensity, immediately after the application and the maintenance of the analgesic effect for up to 2 h, respectively.

Findings

Immediately post-intervention, the proportion of women whose perineal pain decreased ≥30% was significantly higher in the experimental group. Within 2 h, there was no significant difference in the pain levels in both groups. Within 2 h, for 61.9% and 89.3% of women in the experimental and control group, respectively, the perineal pain levels remained unchanged. For the remaining participants, perineal pain was increasing after an average time of 1 h 45 min and 1 h 56 min for the experimental and control groups, respectively.

Conclusion

By applying an ice-pack for 10 min to the perineum, effective pain relief is achieved, that is maintained for between 1 h 45 min and 2 h.  相似文献   
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